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generating pdf fails depending on page layout order

Rob Sargent

2012-05-31

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We're using FOP-1.0.

Admittedly it may be a stretch to call these "simple" page layouts but the attached FOs show that the ordering of the page layouts can cause the generation of the pdf to fail.  The fo-fails.xml exists with

Caused by: java.lang.UnsupportedOperationException: Don't know how to restart at positionNonLeafPos:927(Flow@61f93f69[@id=]], NonLeafPos:399(BlockContainer@52ab9d99[@id=group-Normal Development and Anatomy of the Cerebral Commissures]], NonLeafPos:106(BlockContainer@e09d7b9[@id=]], NonLeafPos:7(Block@58a2b90b[@id=]], LeafPos:-1(pos=29, lm=Block@58a2b90b[@id=]])))))
    at org.apache.fop.layoutmgr.AbstractBreaker.doLayout(AbstractBreaker.java:377)
    at org.apache.fop.layoutmgr.PageBreaker.doLayout(PageBreaker.java:85)
    at org.apache.fop.layoutmgr.PageSequenceLayoutManager.activateLayout(PageSequenceLayoutManager.java:107)
    at org.apache.fop.area.AreaTreeHandler.endPageSequence(AreaTreeHandler.java:238)
    at org.apache.fop.fo.pagination.PageSequence.endOfNode(PageSequence.java:120)
    at org.apache.fop.fo.FOTreeBuilder$MainFOHandler.endElement(FOTreeBuilder.java:349)
    at org.apache.fop.fo.FOTreeBuilder.endElement(FOTreeBuilder.java:177)
    at com.sun.org.apache.xml.internal.serializer.ToXMLSAXHandler.endElement(ToXMLSAXHandler.java:261)
    at org.jdom.output.SAXOutputter.endElement(SAXOutputter.java:1046)
    at org.jdom.output.SAXOutputter.element(SAXOutputter.java:903)
    at org.jdom.output.SAXOutputter.elementContent(SAXOutputter.java:1093)
    at org.jdom.output.SAXOutputter.elementContent(SAXOutputter.java:1067)
    at org.jdom.output.SAXOutputter.element(SAXOutputter.java:897)
    at org.jdom.output.SAXOutputter.output(SAXOutputter.java:621)
    at org.jdom.transform.JDOMSource$DocumentReader.parse(JDOMSource.java:476)
    at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transformIdentity(TransformerImpl.java:636)
    at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:707)
    ... 7 more
Some explaintion of the intent:  The "three-side-page-*" s-m-ps usurp a two-column text xsl-region body placing a static region over one of the columns and the gallery6-page-* attempt to set the size of the region-body to zero (creating a 'text-less' page).

Note that the gallery6-page-* layout was recently reworked to be textless.  Prior to that (developed originally in FOP-0.95) we had an inch of text available and detected no order dependency amongst the orderings of layouts.

And yes the s-m-ps are generated on the fly by the xsl translation, whereby a static page definitions is loaded into a page-number specific master, also left/right adjusted.

Furthermore, in other we also experience a single line of text on the gallery6-page-*s only when preceded by a three-side-page-* s-m-p. If necessary I will report that as a separate issue, but at this point I'm hoping both symptoms are tightly related.

Any work-around much appreciated.  If requested, I'm more than willing to report this as a bug.  U
nfortunately we cannot wait for FOP-1.1 but we could run off the trunk.

As I see it the diffs in the two attached FO's are entirely in the static-regions as one would expect.

We're at crunch time and could go back to the original definition of gallery6-page* but would /really/ rather not.

Cheers,

rjs

<?xml version="1.0" encoding="UTF-8"?>
<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xalan="http://xml.apache.org/xslt" xmlns:tags="xalan://com.amirsys.printing.renderer.acres.ProseFigureReference" xmlns:ec="xalan://com.amirsys.utilities.ElementConversion">
<fo:layout-master-set>
  <fo:simple-page-master margin="0.0in 0.0in 0.6in 0.833in" page-width="8.5in" page-height="11in" master-name="chapter-open">
   <fo:region-body column-gap="0.4in" margin-right="0.7in" margin-top="3in" column-count="2" />
   <fo:region-before extent="3in" margin-right="0.7in" column-gap="0.4in" column-count="2" region-name="chapter-title" />
  </fo:simple-page-master>
  <fo:simple-page-master margin="0.0in 0.0in 0.6in 0.833in" page-width="8.5in" page-height="11in" master-name="chapter-refs-right">
   <fo:region-body column-gap="0.4in" margin-left="0.7in" margin-top="0.50in" column-count="2" />
   <fo:region-before extent="0.50in" column-gap="0.4in" column-count="2" region-name="default-right-header" />
  </fo:simple-page-master>
  <fo:simple-page-master margin=" 0.0in 0.833in 0.6in 0.0in" page-width="8.5in" page-height="11in" master-name="chapter-refs-left">
   <fo:region-body column-gap="0.4in" margin-right="0.7in" margin-top="3in" column-count="2" />
   <fo:region-before extent="3in" column-gap="0.4in" column-count="2" region-name="default-left-header" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="three-side-page-2" margin=" 0.0in 0.833in 0.6in 0.0in">
   <fo:region-body margin-left="4.3585in" margin-top="0.75in" column-count="1" />
   <fo:region-before precedence="true" extent="0.50in" region-name="default-left-header" />
   <fo:region-start extent="3.465in" region-name="three-side-start-2" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="gallery6-page-3" margin="0.0in 0.0in 0.0in 0.833in">
   <fo:region-body margin-right="0.70in" margin-bottom="0.0in" margin-top="11.0in" background-color="orange" column-gap="0.40in" column-count="2" />
   <fo:region-before precedence="true" extent="11in" region-name="header-gallery6-page-3" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="three-side-page-4" margin=" 0.0in 0.833in 0.6in 0.0in">
   <fo:region-body margin-left="4.3585in" margin-top="0.75in" column-count="1" />
   <fo:region-before precedence="true" extent="0.50in" region-name="default-left-header" />
   <fo:region-start extent="3.465in" region-name="three-side-start-4" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="all-text-page-5" margin="0.0in 0.0in 0.6in 0.833in">
   <fo:region-body margin-top="0.75in" margin-right="0.70in" margin-bottom="0.0in" column-gap="0.40in" column-count="2" />
   <fo:region-before precedence="true" extent="0.75in" region-name="default-right-header" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="all-text-page-6" margin=" 0.0in 0.833in 0.6in 0.0in">
   <fo:region-body margin-top="0.75in" margin-left="0.70in" margin-bottom="0in" column-gap="0.40in" column-count="2" />
   <fo:region-before extent="0.50in" precedence="true" region-name="default-left-header" />
  </fo:simple-page-master>
  <fo:page-sequence-master master-name="document-sequence">
   <fo:single-page-master-reference master-reference="chapter-open" />
   <fo:single-page-master-reference master-reference="three-side-page-2" />
   <fo:single-page-master-reference master-reference="gallery6-page-3" />
   <fo:single-page-master-reference master-reference="three-side-page-4" />
   <fo:single-page-master-reference master-reference="all-text-page-5" />
   <fo:single-page-master-reference master-reference="all-text-page-6" />
   <fo:repeatable-page-master-alternatives>
    <fo:conditional-page-master-reference page-position="any" odd-or-even="even" master-reference="chapter-refs-left" blank-or-not-blank="any" />
    <fo:conditional-page-master-reference page-position="any" odd-or-even="odd" master-reference="chapter-refs-right" blank-or-not-blank="any" />
   </fo:repeatable-page-master-alternatives>
  </fo:page-sequence-master>
</fo:layout-master-set>
<fo:page-sequence force-page-count="end-on-even" initial-page-number="1" master-reference="document-sequence">
  <fo:static-content flow-name="chapter-title">
   <fo:block span="all">
    <fo:table width="100%" table-layout="fixed">
      <fo:table-column column-width="proportional-column-width(1)" />
      <fo:table-column column-width="0.70in" />
      <fo:table-body>
       <fo:table-row height="0.8in">
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block>24</fo:block>
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell>
          <fo:table width="100%" table-layout="fixed">
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-body>
            <fo:table-row>
              <fo:table-cell>
               <fo:block />
              </fo:table-cell>
              <fo:table-cell>
               <fo:block>
                <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="middle" color="#2F4886" leader-pattern="rule" />
               </fo:block>
              </fo:table-cell>
              <fo:table-cell>
               <fo:block />
              </fo:table-cell>
            </fo:table-row>
           </fo:table-body>
          </fo:table>
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell height="1.3in" display-align="center" text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block>Commissural and Cortical Maldevelopment</fo:block>
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
      </fo:table-body>
    </fo:table>
   </fo:block>
  </fo:static-content>
  <fo:static-content flow-name="default-left-header">
   <fo:block-container background-color="#E6FAF5" text-indent="0.70in" white-space-collapse="false" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       <fo:page-number />
       Section to be Named Later
      </fo:inline>
    </fo:block>
   </fo:block-container>
  </fo:static-content>
  <fo:static-content flow-name="default-right-header">
   <fo:block-container white-space-collapse="false" last-line-end-indent="0.70in" text-align-last="end" text-align="right" background-color="#E6FAF5" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       Commissural and Cortical Maldevelopment
       <fo:page-number />
      </fo:inline>
    </fo:block>
   </fo:block-container>
  </fo:static-content>
  <fo:static-content flow-name="three-side-start-2">
   <fo:table width="100%" space-before="10pt" table-layout="fixed">
    <fo:table-column column-width="0.70in" />
    <fo:table-column column-width="2.6in" />
    <fo:table-body>
      <fo:table-row height="8pt">
       <fo:table-cell number-columns-spanned="1">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_11_130871512" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-1. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Sagittal graphic depicts the anterior commissure
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               and corpus callosum segments: Rostrum
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , genu
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , body
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , isthmus
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , splenium
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_12_1276360902" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-2. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Graphic depicts fibers from corona radiata converging into and crossing transversely through the corpus callosum
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_33_678428392" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-3. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               DTI shows the normal red "X-shape" corpus callosum formed by the genu
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               and forceps minor, body
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , and splenium
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               with forceps major.
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
   </fo:table>
  </fo:static-content>
  <fo:static-content flow-name="header-gallery6-page-3">
   <fo:block-container white-space-collapse="false" last-line-end-indent="0.70in" text-align-last="end" text-align="right" background-color="#E6FAF5" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       Commissural and Cortical Maldevelopment
       <fo:page-number />
      </fo:inline>
    </fo:block>
   </fo:block-container>
   <fo:table background-color="yellow" width="100%" padding-after="2pt" space-before="5pt" border-collapse="separate" table-layout="fixed">
    <fo:table-column column-width="2.5in" />
    <fo:table-column column-width="0.156in" />
    <fo:table-column column-width="2.5in" />
    <fo:table-column column-width="0.150in" />
    <fo:table-column column-width="1.60in" />
    <fo:table-body>
      <fo:table-row height="8pt">
       <fo:table-cell number-columns-spanned="5">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row>
       <fo:table-cell>
        <fo:block>
          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_127_1668367169" />
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_128_1799221052" />
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden" text-align="left" font-style="italic" height="2.62in">
          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-4. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-5. </fo:inline>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="8pt">
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          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_124_1703247611" />
        </fo:block>
       </fo:table-cell>
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        <fo:block />
       </fo:table-cell>
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          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_119_963145881" />
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden" text-align="left" font-style="italic" height="2.62in">
          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-6. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-7. </fo:inline>
           Sagittal T1WI shows classic subcortical band heterotopia with thin outer cortex, myelinated WM, band of GM
           <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
           , periventricular WM.
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          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_122_2114458175" />
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
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          <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.5in" height="2.5in" src="ref_121_1759011954" />
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
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       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden" text-align="left" font-style="italic" height="2.62in">
          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-8. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-9. </fo:inline>
           Axial section shows mostly the appearance of perisylvian thick cortex
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           although a slight "pebbly" appearance with irregular GM-WM interface can be discerned
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           (courtesy R Hewlett, MD).
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
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  </fo:static-content>
  <fo:static-content flow-name="three-side-start-4">
   <fo:table width="100%" space-before="10pt" table-layout="fixed">
    <fo:table-column column-width="0.70in" />
    <fo:table-column column-width="2.6in" />
    <fo:table-body>
      <fo:table-row height="8pt">
       <fo:table-cell number-columns-spanned="1">
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       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
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          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_27_1769441774" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-10. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               CC agenesis shows "Viking helmet" appearance with high, wide 3rd ventricle
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               , pointed nonconverging lateral ventricles
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               , Probst bundles
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               .
              </fo:inline>
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      <fo:table-row height="7pt">
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          </fo:block>
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      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
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        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-11. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Coronal autopsy of CC agenesis shows thin 3rd ventricle roof, Probst bundles
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               .
              </fo:inline>
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      <fo:table-row height="7pt">
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      <fo:table-row height="2.6in">
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        <fo:block />
       </fo:table-cell>
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          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_25_1315614368" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden">
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           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-12. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               CC agenesis shows absent cingulate gyrus, "radiating" gyri
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               converging on high-riding 3rd ventricle
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               . (Courtesy R. Hewlett, MD.)
              </fo:inline>
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          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
   </fo:table>
  </fo:static-content>
  <fo:flow font-size="10.5pt" font-family="TimesNewRomanPSMT" flow-name="xsl-region-body">
   <fo:block font-size="10pt" font-family="GillSansMTPro" border="0.6pt solid black" background-color="#E6FAF5">
    <fo:list-block padding-after="5pt" padding-before="6pt" provisional-label-separation="3pt" provisional-distance-between-starts="0.135in">
      <fo:list-item space-before="2pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block />
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block margin-right="10pt" text-align-last="justify">
          Normal Development and Anatomy of the Cerebral Commissures
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="group-Normal Development and Anatomy of the Cerebral Commissures" />
        </fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item margin-left="9pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block line-height="1.0" font-size="9pt" />
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block margin-right="10pt" text-align-last="justify" font-weight="normal" font-size="9pt">
          Normal Development
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Normal Development" />
        </fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item margin-left="9pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block line-height="1.0" font-size="9pt" />
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block margin-right="10pt" text-align-last="justify" font-weight="normal" font-size="9pt">
          Normal Gross and Imaging Anatomy
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Normal Gross and Imaging Anatomy" />
        </fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item space-before="2pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block />
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block margin-right="10pt" text-align-last="justify">
          Commissural Anomalies
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="group-Commissural Anomalies" />
        </fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item margin-left="9pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block line-height="1.0" font-size="9pt" />
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block margin-right="10pt" text-align-last="justify" font-weight="normal" font-size="9pt">
          Callosal Dysgenesis Spectrum
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Callosal Dysgenesis Spectrum" />
        </fo:block>
       </fo:list-item-body>
      </fo:list-item>
    </fo:list-block>
   </fo:block>
   <fo:block-container language="en" hyphenate="true" padding-after="18pt" space-before="12pt" font-size="10.5pt" font-family="TimesNewRomanPSMT">
    <fo:block text-align="justify" space-before="6pt">Corpus callosum dysgenesis and malformations of cortical development are some of the most common congenital brain anomalies. They can occur in isolation but frequently accompany other disorders such as Dandy-Walker spectrum, Chiari II malformation, and malformations of the hypothalamus and pituitary gland.</fo:block>
   </fo:block-container>
   <fo:block keep-with-next="always">
    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
    <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Normal Development and Anatomy of the Cerebral Commissures</fo:block>
    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
   </fo:block>
   <fo:block-container language="en" hyphenate="true" font-family="TimesNewRomanPSMT" font-size="10.5pt" id="group-Normal Development and Anatomy of the Cerebral Commissures">
    <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
      <fo:block text-align="justify" space-before="6pt">The telencephalon has three major commissural tracts: The corpus callosum (the largest and most prominent), the anterior commissure, and the hippocampal (posterior) commissure. Coordinated transfer of information between the cerebral hemispheres is essential for normal function and occurs via these three axonal commissures.</fo:block>
      <fo:block text-align="justify" space-before="6pt">In this section we briefly review the normal development of the commissures and then delineate their gross and imaging anatomy.</fo:block>
    </fo:block>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Normal Development">Normal Development</fo:block>
      <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
       <fo:block text-align="justify" space-before="3pt">Commissural development is a complex process in which axons from cortical neurons are actively guided across the midline to reach their targets in the contralateral hemisphere. A set of genetically-mediated guidance mechanisms are used by these axons from cortical neurons to locate and innervate their targets. Details of this process are beyond the scope of this text but are summarized briefly below. The interested reader is referred to the excellent text by Barkovich and Raybaud.</fo:block>
       <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Commissural Plate</fo:block>
       <fo:block text-align="justify" space-before="3pt">The commissural plate (CP) is a band of tissue within which all telencephalic commissures cross the midline into the contralateral hemisphere during embryonic development. The CP consists of multiple molecular domains, each of which is associated with separate genetic expressions and specific commissural projections. Correct CP development is required for normal forebrain commissural formation.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Specialized glial cells in the anterior CP (the "subcallosal glial sling") together with a second set of midline glial populations (the glial "wedge" below and the indusium griseum glia above) form the foundation for axonal ingrowth and crossing. The subcallosal sling, the two midline glial populations, and "pioneering axons" all work in unison to guide axons across the midline.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The anterior commissure (AC) is the first forebrain commissure to develop and sends a group of "pioneering axons" across the midline during the eighth fetal week. Near the end of the first trimester, axons that will eventually form the anterior segments of the corpus callosum (CC) begin navigating from the cortex towards the midline near the embryonic foramen of Monro.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The hippocampal commissure forms posteriorly around week 11 and is followed by axons that will eventually become the posterior body and splenium of the corpus callosum.</fo:block>
       <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Corpus Callosum</fo:block>
       <fo:block text-align="justify" space-before="3pt">The CC forms in two independent segments, with some axons crossing the glial sling anteriorly and others following the hippocampal commissure posteriorly. Fiber bundles in the anterior and posterior callosum are initially separated but eventually unite to form a single continuous structure, the definitive corpus callosum.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The first axons cross the midline at 13-14 fetal weeks and the last finally cross between 18-20 weeks. The genu, rostrum, and body form in rapid succession and can clearly be identified at 15 weeks while the caudal portion--the splenium--does not become prominent until 18-19 weeks.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The CC in the fetus and preterm infant is very thin and relatively uniform in gross appearance. At birth, it is still comparatively thin and quite flat. The CC continues to grow and its shape evolves for several months after birth.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Myelination of the splenium generally precedes genu maturation. As myelination proceeds, the genu and splenium thicken noticeably. Both the length and thickness of the CC gradually increase. By 10 postnatal months the overall appearance resembles that of a normal adult although some myelination continues into young adulthood.</fo:block>
      </fo:block>
    </fo:block-container>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Normal Gross and Imaging Anatomy">Normal Gross and Imaging Anatomy</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Corpus Callosum</fo:block>
      <fo:block text-align="justify" space-before="3pt">
       The CC is the largest of the three forebrain commissures and is composed of five parts. From front to back these are the rostrum, genu, body, isthmus, and splenium. The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">rostrum</inline>
       is the smallest segment and connects the orbital surfaces of the frontal lobes. A prominent anterior "knee--the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">genu</inline>
       --connects the lateral and medial frontal lobes. White matter fibers that curve anterolaterally from the genu form the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">forceps minor</inline>
       .
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">
       The longest CC segment is the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">body</inline>
       . Its fibers pass laterally and intersect with projection fibers of the corona radiata. The body connects broad regions of each hemispheric cortex together.
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">
       The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">isthmus</inline>
       is a shorter, slightly more narrow area that lies between the posterior body and splenium. The isthmus connects the pre- and postcentral gyri and auditory cortex with their counterparts in the contralateral hemisphere. The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">splenium</inline>
       is the expanded, rounded termination of the CC. MOst of its fibers curve into the occipital lobes as the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">forceps major</inline>
       .
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">Sagittal T1- and T2WIs demonstrate the rostrum as a thin WM tract that curves posteroinferiorly from the genu. The dorsal CC surface is typically not straight, but has a slightly "wavy" with a distinct posterior narrowing--the isthmus--just before the the CC widens again into the splenium.</fo:block>
      <fo:block text-align="justify" space-before="6pt">Coronal scans show the CC curving from side to side across the midline. Anteriorly, the genu is seen as a continuous band of WM connecting the frontal lobes. More posteriorly, the CC lies above the fornices, fanning out from the splenium into the forceps major.</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Anterior Commissure</fo:block>
      <fo:block text-align="justify" space-before="3pt">The anterior commissure (AC) is a transversely-oriented bundle of compact, heavily-myelinated fibers that crosses the midline anterior to the fornix.</fo:block>
      <fo:block text-align="justify" space-before="6pt">The AC lies in the anterior wall of the third ventricle. From the midline, it curves laterally in the basal forebrain and splits into two bundles. The smaller more anterior bundle courses toward the orbitofrontal cortex and olfactory tract. The much larger posterior bundle fans out into the temporal lobe. The AC connects the anterior parts of the temporal lobes and lies anterosuperior to the temporal horn of the lateral ventricle.</fo:block>
      <fo:block text-align="justify" space-before="6pt">On sagittal T1WIs the AC is seen as a hyperintense ovoid structure lying midway up the anterior wall of the third ventricle. On axial T2WIs it can be identified as a compact well-defined hypointense band of tissue lying just in front of the third ventricle. As it courses laterally, both sides of the AC curve slightly anteriorly so it resembles an archer's bow on axial MR scans.</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Hippocampal Commissure</fo:block>
      <fo:block text-align="justify" space-before="3pt">The hippocampal commissure (HC) is the smallest of the three major commissures but the earliest to develop. It is a transversely-oriented fiber bundle that crosses the midline in the posterior pineal lamina.</fo:block>
      <fo:block text-align="justify" space-before="6pt">In contrast to the CC and AC, the HC is less easily distinguished on MR scans. In the midline sagittal plane, its myelinated fibers blend imperceptibly with those of the inferomedial WM in the corpus callosum splenium. On coronal scans through the lateral ventricle atria the HC can be seen lying below the corpus callosum where its fibers blend in with those of the fornices.</fo:block>
    </fo:block-container>
   </fo:block-container>
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    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
    <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Commissural Anomalies</fo:block>
    <fo:block space-before="12pt" keep-with-next="auto" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
   </fo:block>
   <fo:block-container language="en" hyphenate="true" font-family="TimesNewRomanPSMT" font-size="10.5pt" id="group-Commissural Anomalies">
    <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
      <fo:block text-align="justify" space-before="6pt">Anomalies of the cerebral commissures are the most common of all brain malformations and have been described in nearly 200 different syndromes! Any one or a combination of the three forebrain commissures can be affected by developmental failures. Recognizing the surprisingly broad spectrum of commissural malformations and delineating any associated abnormalities is essential for accurate, complete diagnosis.</fo:block>
      <fo:block text-align="justify" space-before="6pt">We begin this section by discussing the spectrum of corpus callosum malformations together with a few associated lesions and some representative syndromes. Meningeal dysplasias such as interhemispheric cysts and lipomas are common. Lipomas are discussed in detail in the concluding chapter of this book. Developmental lesions of the pituitary gland and hypothalamus--both frequently associated with callosal dysgenesis--are delineated in chapter   .</fo:block>
    </fo:block>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Callosal Dysgenesis Spectrum">Callosal Dysgenesis Spectrum</fo:block>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Terminology</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        The corpus callosum can be completely absent (agenesis) or partially formed (hypogenetic or dysgenetic).
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">Complete CC agenesis</inline>
        almost always is accompanied by absence of the hippocampal commissure (HC) although the anterior commissure (AC) is usually present and normal.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        In
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">partial posterior agenesis</inline>
        , the HC and posterior callosum (the splenium, with or without some involvement of the body) are both absent. In rare instances, the CC is completely absent but the HC is present. If all three commissures fail to develop at all, the result is termed
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">tricommissural agenesis</inline>
        .
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Etiology</fo:block>
       <fo:block text-align="justify" space-before="3pt">When the underlying mechanisms that regulate the guidance of commissural fibers fail, pathological dysgenesis of one or more commissures ensues. To date, nearly 40 genes have been linked to human callosal dysgenesis.</fo:block>
       <fo:block text-align="justify" space-before="6pt">CC anomalies can result from failure of axons themselves to form, failure of genetically-determined molecular guidance mechanisms, failure of the glial sling or hippocampal commissure to develop normally, or malfunction of these substrates in guiding axons to their proper destinations across the midline.</fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Pathology</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        In complete CC agenesis, no segments are present. Sagittal sections show an
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">absent cingulate gyrus</inline>
        while the hemispheres demonstrate a radiating
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">"spoke-wheel" gyral pattern</inline>
        extending perpendicularly to the roof of the third ventricle.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        On coronal sections the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">"high-riding" third ventricle</inline>
        looks as if it opens directly into the interhemispheric fissure but is actually covered by a thin membranous roof that bulges into the interhemispheric fissure, displacing the fornices laterally. The lateral ventricles have upturned, pointed corners.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        A prominent longitudinal WM tract called the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">Probst bundle</inline>
        is situated just inside the apex of each ventricle. These bundles consist of the misdirected commissural fibers that should have crossed the midline but instead course from front to back, indenting the medial walls of the lateral ventricles.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">The septum pellucidum often appears to be absent but instead has widely separated leaves that course laterally--not vertically--from the fornices to the Probst bundles.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Axial sections show the lateral ventricles are parallel and nonconverging. The occipital horns are often disproportionately dilated, a condition termed colpocephaly.</fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Clinical Issues</fo:block>
       <fo:block text-align="justify" space-before="3pt" font-weight="normal" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Epidemiology and Demographics.</fo:inline>
        <fo:inline font-weight="normal">CC dysgenesis can be discovered at any age. It has a prevalence of at least 1:4,000 live births. CC dysgenesis is the most common CNS malformation and is found in 3-5% of individuals with neurodevelopmental disorders. Nonsyndromic CC dysgenesis has a slight male predominance.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Presentation.</fo:inline>
        <fo:inline font-weight="normal">MInor CC dysgenesis is often discovered incidentally on imaging studies or at autopsy. Major commissural malformations are associated with seizures, developmental delay, and symptoms secondary to disruptions of the hypothalamic-pituitary axis.</fo:inline>
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Imaging Findings</fo:block>
       <fo:block text-align="justify" space-before="3pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">CT Findings.</fo:inline>
        <fo:inline font-weight="normal">Axial NECT scans show parallel, nonconverging, widely separated lateral ventricles. Disproportionate enlargement of the occipital horns is common.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">MR Findings.</fo:inline>
        <fo:inline font-weight="normal">Sagittal T1- and T2WIs demonstrate partial dysgenesis or complete CC absence. With complete agenesis, the third ventricle appears continuous with the interhemispheric fissure and is surrounded dorsally by fingers of radiating gyri that "point" towards the third ventricle. In partial agenesis, the rostrum and splenium are often absent and the remaining genu and body have a "blocky" thickened appearance. The hippocampal commissure is typically absent but the AC may be preserved and often appears quite normal or even larger than usual.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">A midline interhemispheric cyst may be present above the third ventricle. Such cysts can be a ventricular outpouching or separate structures that do not communicate with the ventricular system.</fo:block>
       <fo:block text-align="justify" space-before="6pt">An azygous anterior cerebral artery (ACA) can be seen "wandering" upwards in the interhemispheric fissure. Look for associated malformations of the eyes, hindbrain, and hypothalamic-pituitary axis.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Axial scans demonstrate the parallel lateral ventricles especially well. The prominent myelinated tracts of the Probst bundles can appear quite prominent.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Coronal scans show a "Viking helmet" or "moose-head" appearance caused by the curved, upwardly pointed lateral ventricles and high-riding third ventricle that expands into the interhemispheric fissure. The Probst bundles are seen as densely myelinated tracts lying just inside the lateral ventricle bodies. The hippocampi appear abnormally rounded and vertically-oriented. Moderately enlarged temporal horns are common. Look for malformations such as heterotopic gray matter.</fo:block>
       <fo:block text-align="justify" space-before="6pt">DTI is especially helpful in depicting CC agenesis. The normal red (right-to-left encoded) color of the corpus callosum is absent. Instead, prominent front to back (green) tracts of the Probst bundles are seen.</fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Angiography.</fo:inline>
        <fo:inline font-weight="normal">In complete CC agenesis, CTA, DSA, and MRA demonstrate an azygous ACA that courses directly upwards in the interhemispheric fissure.</fo:inline>
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Differential Diagnosis</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        The major differential diagnosis of CC dysgenesis is destruction caused by
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">trauma, surgery (callosotomy), or ischemia</inline>
        . Occasionally the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">hippocampal commissure</inline>
        forms while the CC is absent and may mimic a remnant portion of the CC on sagittal images. Coronal views show the HC connects the fornices, not the hemispheres.
       </fo:block>
      </fo:block-container>
    </fo:block-container>
   </fo:block-container>
   <fo:block break-before="page" font-size="9pt">
    <fo:block keep-with-next="auto">
      <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
       <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
      </fo:block>
      <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Selected References</fo:block>
      <fo:block space-before="12pt" keep-with-next="auto" margin-left="-15pt">
       <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
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    </fo:block>
    <fo:block language="en" hyphenate="false" color="#2F4886" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-style="italic" font-size="16pt">Normal Development and Anatomy of the Cerebral Commissures</fo:block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Normal Development</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Barkovich AJ et al: Congenital malformations of the brain and skull. In X Y (et al): Pediatric Neuroimaging. 5th ed. Philadelphia: Lippincott Williams &amp; Wilkins. 368-83, 2012; name of general editor(s) missing from this cite. I also suspect the pub date is 2011 rather than 2012, but not sure. Pretty sure the full cite for this book exists elsewhere in this book; find it and match it.</fo:block>
        </fo:list-item-body>
       </fo:list-item>
      </fo:list-block>
    </fo:block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Normal Gross and Imaging Anatomy</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Peltier J et al: Microsurgical anatomy of the anterior commissure: correlations with diffusion tensor imaging fiber tracking and clinical relevance. Neurosurgery. 69(2 Suppl Operative):241-6; discussion 246-7, 2011</fo:block>
        </fo:list-item-body>
       </fo:list-item>
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Wang F et al: Microsurgical and tractographic anatomical study of insular and transsylvian transinsular approach. Neurol Sci. 32(5):865-74, 2011</fo:block>
        </fo:list-item-body>
       </fo:list-item>
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Patel MD et al: Distribution and fibre field similarity mapping of the human anterior commissure fibres by diffusion tensor imaging. MAGMA. 23(5-6):399-408, 2010</fo:block>
        </fo:list-item-body>
       </fo:list-item>
      </fo:list-block>
    </fo:block>
    <fo:block language="en" hyphenate="false" color="#2F4886" margin-left="-15pt" keep-with-next="auto" space-before="12pt" font-style="italic" font-size="16pt">Commissural Anomalies</fo:block>
    <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
      <fo:list-item space-before="3pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block>Barkovich AJ: Congenital malformations overview. In Osborn AG et al: Diagnostic Imaging: Brain. 2nd ed. Salt Lake City: Amirsys. I-1-2 to I-1-5, 2010</fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item space-before="3pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block>Ren T et al: Imaging, anatomical, and molecular analysis of callosal formation in the developing human fetal brain. Anat Rec A Discov Mol Cell Evol Biol. 288(2):191-204, 2006</fo:block>
       </fo:list-item-body>
      </fo:list-item>
    </fo:list-block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Callosal Dysgenesis Spectrum</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Paul LK: Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement. J Neurodev Disord. 3(1):3-27, 2011</fo:block>
        </fo:list-item-body>
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   <fo:region-before precedence="true" extent="11in" region-name="header-gallery6-page-4" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="all-text-page-5" margin="0.0in 0.0in 0.6in 0.833in">
   <fo:region-body margin-top="0.75in" margin-right="0.70in" margin-bottom="0.0in" column-gap="0.40in" column-count="2" />
   <fo:region-before precedence="true" extent="0.75in" region-name="default-right-header" />
  </fo:simple-page-master>
  <fo:simple-page-master page-width="8.5in" page-height="11in" master-name="all-text-page-6" margin=" 0.0in 0.833in 0.6in 0.0in">
   <fo:region-body margin-top="0.75in" margin-left="0.70in" margin-bottom="0in" column-gap="0.40in" column-count="2" />
   <fo:region-before extent="0.50in" precedence="true" region-name="default-left-header" />
  </fo:simple-page-master>
  <fo:page-sequence-master master-name="document-sequence">
   <fo:single-page-master-reference master-reference="chapter-open" />
   <fo:single-page-master-reference master-reference="three-side-page-2" />
   <fo:single-page-master-reference master-reference="three-side-page-3" />
   <fo:single-page-master-reference master-reference="gallery6-page-4" />
   <fo:single-page-master-reference master-reference="all-text-page-5" />
   <fo:single-page-master-reference master-reference="all-text-page-6" />
   <fo:repeatable-page-master-alternatives>
    <fo:conditional-page-master-reference page-position="any" odd-or-even="even" master-reference="chapter-refs-left" blank-or-not-blank="any" />
    <fo:conditional-page-master-reference page-position="any" odd-or-even="odd" master-reference="chapter-refs-right" blank-or-not-blank="any" />
   </fo:repeatable-page-master-alternatives>
  </fo:page-sequence-master>
</fo:layout-master-set>
<fo:page-sequence force-page-count="end-on-even" initial-page-number="1" master-reference="document-sequence">
  <fo:static-content flow-name="chapter-title">
   <fo:block span="all">
    <fo:table width="100%" table-layout="fixed">
      <fo:table-column column-width="proportional-column-width(1)" />
      <fo:table-column column-width="0.70in" />
      <fo:table-body>
       <fo:table-row height="0.8in">
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block>24</fo:block>
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell>
          <fo:table width="100%" table-layout="fixed">
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-column column-width="proportional-column-width(1)" />
           <fo:table-body>
            <fo:table-row>
              <fo:table-cell>
               <fo:block />
              </fo:table-cell>
              <fo:table-cell>
               <fo:block>
                <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="middle" color="#2F4886" leader-pattern="rule" />
               </fo:block>
              </fo:table-cell>
              <fo:table-cell>
               <fo:block />
              </fo:table-cell>
            </fo:table-row>
           </fo:table-body>
          </fo:table>
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell height="1.3in" display-align="center" text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block>Commissural and Cortical Maldevelopment</fo:block>
        </fo:table-cell>
        <fo:table-cell>
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
       <fo:table-row>
        <fo:table-cell text-align="center" font-size="36pt" font-family="TimesNewRomanPSMT">
          <fo:block />
        </fo:table-cell>
       </fo:table-row>
      </fo:table-body>
    </fo:table>
   </fo:block>
  </fo:static-content>
  <fo:static-content flow-name="default-left-header">
   <fo:block-container background-color="#E6FAF5" text-indent="0.70in" white-space-collapse="false" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       <fo:page-number />
       Section to be Named Later
      </fo:inline>
    </fo:block>
   </fo:block-container>
  </fo:static-content>
  <fo:static-content flow-name="default-right-header">
   <fo:block-container white-space-collapse="false" last-line-end-indent="0.70in" text-align-last="end" text-align="right" background-color="#E6FAF5" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       Commissural and Cortical Maldevelopment
       <fo:page-number />
      </fo:inline>
    </fo:block>
   </fo:block-container>
  </fo:static-content>
  <fo:static-content flow-name="three-side-start-2">
   <fo:table width="100%" space-before="10pt" table-layout="fixed">
    <fo:table-column column-width="0.70in" />
    <fo:table-column column-width="2.6in" />
    <fo:table-body>
      <fo:table-row height="8pt">
       <fo:table-cell number-columns-spanned="1">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_11_130871512" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-1. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Sagittal graphic depicts the anterior commissure
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               and corpus callosum segments: Rostrum
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , genu
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , body
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , isthmus
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , splenium
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_12_1276360902" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-2. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Graphic depicts fibers from corona radiata converging into and crossing transversely through the corpus callosum
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_33_678428392" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
       <fo:table-cell>
        <fo:block-container overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-3. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               DTI shows the normal red "X-shape" corpus callosum formed by the genu
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               and forceps minor, body
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , and splenium
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="white_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               with forceps major.
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
   </fo:table>
  </fo:static-content>
  <fo:static-content flow-name="three-side-start-3">
   <fo:table width="100%" space-before="10pt" table-layout="fixed">
    <fo:table-column column-width="2.6in" />
    <fo:table-column column-width="0.70in" />
    <fo:table-body>
      <fo:table-row height="8pt">
       <fo:table-cell number-columns-spanned="1">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_27_1769441774" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-4. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               CC agenesis shows "Viking helmet" appearance with high, wide 3rd ventricle
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , pointed nonconverging lateral ventricles
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_curve" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               , Probst bundles
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_24_1921973409" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block-container height="0.45in" overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-5. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               Coronal autopsy of CC agenesis shows thin 3rd ventricle roof, Probst bundles
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               .
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="7pt">
       <fo:table-cell number-columns-spanned="2">
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="2.6in">
       <fo:table-cell>
        <fo:block>
          <fo:block>
           <fo:external-graphic border-collapse="separate" border="0.5pt solid black" content-width="scale-to-fit" content-height="scale-to-fit" width="2.6in" height="2.6in" src="ref_25_1315614368" />
          </fo:block>
        </fo:block>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
      <fo:table-row height="0.45in">
       <fo:table-cell>
        <fo:block-container overflow="hidden">
          <fo:block>
           <fo:block-container overflow="hidden" height="0.45in">
            <fo:block height="0.5in" font-style="italic" font-size="9pt" font-family="TimesNewRomanPSMT">
              <fo:inline font-weight="bold">Fig. 24-6. </fo:inline>
              <fo:inline font-weight="normal" margin-left="2pt">
               CC agenesis shows absent cingulate gyrus, "radiating" gyri
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_solid" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               converging on high-riding 3rd ventricle
               <external-graphic xmlns="http://www.w3.org/1999/XSL/Format" src="black_open" width="0.14in" height="0.09in" content-height="0.09in" content-width="0.14in" />
               . (Courtesy R. Hewlett, MD.)
              </fo:inline>
            </fo:block>
           </fo:block-container>
          </fo:block>
        </fo:block-container>
       </fo:table-cell>
       <fo:table-cell>
        <fo:block />
       </fo:table-cell>
      </fo:table-row>
    </fo:table-body>
   </fo:table>
  </fo:static-content>
  <fo:static-content flow-name="header-gallery6-page-4">
   <fo:block-container background-color="#E6FAF5" text-indent="0.70in" white-space-collapse="false" height="0.50in" font-size="11pt" font-family="Optima-Oblique">
    <fo:block line-height="0.4in" padding-before="0.2in">
      <fo:inline>
       <fo:page-number />
       Section to be Named Later
      </fo:inline>
    </fo:block>
   </fo:block-container>
   <fo:table background-color="yellow" width="100%" padding-after="2pt" space-before="5pt" border-collapse="separate" table-layout="fixed">
    <fo:table-column column-width="0.70in" />
    <fo:table-column column-width="1.60in" />
    <fo:table-column column-width="0.150in" />
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          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-7. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-8. </fo:inline>
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          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-9. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-10. </fo:inline>
           Sagittal T1WI shows classic subcortical band heterotopia with thin outer cortex, myelinated WM, band of GM
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           , periventricular WM.
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          <fo:block padding-before="1pt" font-size="9pt" font-family="TimesNewRomanPSMT">
           <fo:inline font-weight="bold">Fig. 24-11. </fo:inline>
           <fo:inline font-weight="bold">Fig. 24-12. </fo:inline>
           Axial section shows mostly the appearance of perisylvian thick cortex
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           although a slight "pebbly" appearance with irregular GM-WM interface can be discerned
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           (courtesy R Hewlett, MD).
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          Normal Development and Anatomy of the Cerebral Commissures
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="group-Normal Development and Anatomy of the Cerebral Commissures" />
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          Normal Development
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Normal Development" />
        </fo:block>
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        <fo:block margin-right="10pt" text-align-last="justify" font-weight="normal" font-size="9pt">
          Normal Gross and Imaging Anatomy
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Normal Gross and Imaging Anatomy" />
        </fo:block>
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          Commissural Anomalies
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="group-Commissural Anomalies" />
        </fo:block>
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          Callosal Dysgenesis Spectrum
          <fo:leader leader-pattern="dots" />
          <fo:page-number-citation ref-id="Callosal Dysgenesis Spectrum" />
        </fo:block>
       </fo:list-item-body>
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    <fo:block text-align="justify" space-before="6pt">Corpus callosum dysgenesis and malformations of cortical development are some of the most common congenital brain anomalies. They can occur in isolation but frequently accompany other disorders such as Dandy-Walker spectrum, Chiari II malformation, and malformations of the hypothalamus and pituitary gland.</fo:block>
   </fo:block-container>
   <fo:block keep-with-next="always">
    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
    <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Normal Development and Anatomy of the Cerebral Commissures</fo:block>
    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
   </fo:block>
   <fo:block-container language="en" hyphenate="true" font-family="TimesNewRomanPSMT" font-size="10.5pt" id="group-Normal Development and Anatomy of the Cerebral Commissures">
    <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
      <fo:block text-align="justify" space-before="6pt">The telencephalon has three major commissural tracts: The corpus callosum (the largest and most prominent), the anterior commissure, and the hippocampal (posterior) commissure. Coordinated transfer of information between the cerebral hemispheres is essential for normal function and occurs via these three axonal commissures.</fo:block>
      <fo:block text-align="justify" space-before="6pt">In this section we briefly review the normal development of the commissures and then delineate their gross and imaging anatomy.</fo:block>
    </fo:block>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Normal Development">Normal Development</fo:block>
      <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
       <fo:block text-align="justify" space-before="3pt">Commissural development is a complex process in which axons from cortical neurons are actively guided across the midline to reach their targets in the contralateral hemisphere. A set of genetically-mediated guidance mechanisms are used by these axons from cortical neurons to locate and innervate their targets. Details of this process are beyond the scope of this text but are summarized briefly below. The interested reader is referred to the excellent text by Barkovich and Raybaud.</fo:block>
       <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Commissural Plate</fo:block>
       <fo:block text-align="justify" space-before="3pt">The commissural plate (CP) is a band of tissue within which all telencephalic commissures cross the midline into the contralateral hemisphere during embryonic development. The CP consists of multiple molecular domains, each of which is associated with separate genetic expressions and specific commissural projections. Correct CP development is required for normal forebrain commissural formation.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Specialized glial cells in the anterior CP (the "subcallosal glial sling") together with a second set of midline glial populations (the glial "wedge" below and the indusium griseum glia above) form the foundation for axonal ingrowth and crossing. The subcallosal sling, the two midline glial populations, and "pioneering axons" all work in unison to guide axons across the midline.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The anterior commissure (AC) is the first forebrain commissure to develop and sends a group of "pioneering axons" across the midline during the eighth fetal week. Near the end of the first trimester, axons that will eventually form the anterior segments of the corpus callosum (CC) begin navigating from the cortex towards the midline near the embryonic foramen of Monro.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The hippocampal commissure forms posteriorly around week 11 and is followed by axons that will eventually become the posterior body and splenium of the corpus callosum.</fo:block>
       <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Corpus Callosum</fo:block>
       <fo:block text-align="justify" space-before="3pt">The CC forms in two independent segments, with some axons crossing the glial sling anteriorly and others following the hippocampal commissure posteriorly. Fiber bundles in the anterior and posterior callosum are initially separated but eventually unite to form a single continuous structure, the definitive corpus callosum.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The first axons cross the midline at 13-14 fetal weeks and the last finally cross between 18-20 weeks. The genu, rostrum, and body form in rapid succession and can clearly be identified at 15 weeks while the caudal portion--the splenium--does not become prominent until 18-19 weeks.</fo:block>
       <fo:block text-align="justify" space-before="6pt">The CC in the fetus and preterm infant is very thin and relatively uniform in gross appearance. At birth, it is still comparatively thin and quite flat. The CC continues to grow and its shape evolves for several months after birth.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Myelination of the splenium generally precedes genu maturation. As myelination proceeds, the genu and splenium thicken noticeably. Both the length and thickness of the CC gradually increase. By 10 postnatal months the overall appearance resembles that of a normal adult although some myelination continues into young adulthood.</fo:block>
      </fo:block>
    </fo:block-container>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Normal Gross and Imaging Anatomy">Normal Gross and Imaging Anatomy</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Corpus Callosum</fo:block>
      <fo:block text-align="justify" space-before="3pt">
       The CC is the largest of the three forebrain commissures and is composed of five parts. From front to back these are the rostrum, genu, body, isthmus, and splenium. The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">rostrum</inline>
       is the smallest segment and connects the orbital surfaces of the frontal lobes. A prominent anterior "knee--the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">genu</inline>
       --connects the lateral and medial frontal lobes. White matter fibers that curve anterolaterally from the genu form the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">forceps minor</inline>
       .
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">
       The longest CC segment is the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">body</inline>
       . Its fibers pass laterally and intersect with projection fibers of the corona radiata. The body connects broad regions of each hemispheric cortex together.
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">
       The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">isthmus</inline>
       is a shorter, slightly more narrow area that lies between the posterior body and splenium. The isthmus connects the pre- and postcentral gyri and auditory cortex with their counterparts in the contralateral hemisphere. The
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">splenium</inline>
       is the expanded, rounded termination of the CC. MOst of its fibers curve into the occipital lobes as the
       <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">forceps major</inline>
       .
      </fo:block>
      <fo:block text-align="justify" space-before="6pt">Sagittal T1- and T2WIs demonstrate the rostrum as a thin WM tract that curves posteroinferiorly from the genu. The dorsal CC surface is typically not straight, but has a slightly "wavy" with a distinct posterior narrowing--the isthmus--just before the the CC widens again into the splenium.</fo:block>
      <fo:block text-align="justify" space-before="6pt">Coronal scans show the CC curving from side to side across the midline. Anteriorly, the genu is seen as a continuous band of WM connecting the frontal lobes. More posteriorly, the CC lies above the fornices, fanning out from the splenium into the forceps major.</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Anterior Commissure</fo:block>
      <fo:block text-align="justify" space-before="3pt">The anterior commissure (AC) is a transversely-oriented bundle of compact, heavily-myelinated fibers that crosses the midline anterior to the fornix.</fo:block>
      <fo:block text-align="justify" space-before="6pt">The AC lies in the anterior wall of the third ventricle. From the midline, it curves laterally in the basal forebrain and splits into two bundles. The smaller more anterior bundle courses toward the orbitofrontal cortex and olfactory tract. The much larger posterior bundle fans out into the temporal lobe. The AC connects the anterior parts of the temporal lobes and lies anterosuperior to the temporal horn of the lateral ventricle.</fo:block>
      <fo:block text-align="justify" space-before="6pt">On sagittal T1WIs the AC is seen as a hyperintense ovoid structure lying midway up the anterior wall of the third ventricle. On axial T2WIs it can be identified as a compact well-defined hypointense band of tissue lying just in front of the third ventricle. As it courses laterally, both sides of the AC curve slightly anteriorly so it resembles an archer's bow on axial MR scans.</fo:block>
      <fo:block margin-left="-15pt" space-before="5pt" keep-with-next="always" font-weight="normal" font-size="14pt">Hippocampal Commissure</fo:block>
      <fo:block text-align="justify" space-before="3pt">The hippocampal commissure (HC) is the smallest of the three major commissures but the earliest to develop. It is a transversely-oriented fiber bundle that crosses the midline in the posterior pineal lamina.</fo:block>
      <fo:block text-align="justify" space-before="6pt">In contrast to the CC and AC, the HC is less easily distinguished on MR scans. In the midline sagittal plane, its myelinated fibers blend imperceptibly with those of the inferomedial WM in the corpus callosum splenium. On coronal scans through the lateral ventricle atria the HC can be seen lying below the corpus callosum where its fibers blend in with those of the fornices.</fo:block>
    </fo:block-container>
   </fo:block-container>
   <fo:block keep-with-next="auto">
    <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
    <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Commissural Anomalies</fo:block>
    <fo:block space-before="12pt" keep-with-next="auto" margin-left="-15pt">
      <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
    </fo:block>
   </fo:block>
   <fo:block-container language="en" hyphenate="true" font-family="TimesNewRomanPSMT" font-size="10.5pt" id="group-Commissural Anomalies">
    <fo:block font-weight="normal" font-size="10.5pt" font-family="TimesNewRomanPSMT">
      <fo:block text-align="justify" space-before="6pt">Anomalies of the cerebral commissures are the most common of all brain malformations and have been described in nearly 200 different syndromes! Any one or a combination of the three forebrain commissures can be affected by developmental failures. Recognizing the surprisingly broad spectrum of commissural malformations and delineating any associated abnormalities is essential for accurate, complete diagnosis.</fo:block>
      <fo:block text-align="justify" space-before="6pt">We begin this section by discussing the spectrum of corpus callosum malformations together with a few associated lesions and some representative syndromes. Meningeal dysplasias such as interhemispheric cysts and lipomas are common. Lipomas are discussed in detail in the concluding chapter of this book. Developmental lesions of the pituitary gland and hypothalamus--both frequently associated with callosal dysgenesis--are delineated in chapter   .</fo:block>
    </fo:block>
    <fo:block-container>
      <fo:block hyphenate="false" color="#2F4886" space-before="9pt" keep-with-next="always" font-family="TimesNewRomanPSMT" font-style="italic" font-weight="bold" font-size="16pt" margin-left="-15pt" id="Callosal Dysgenesis Spectrum">Callosal Dysgenesis Spectrum</fo:block>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Terminology</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        The corpus callosum can be completely absent (agenesis) or partially formed (hypogenetic or dysgenetic).
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">Complete CC agenesis</inline>
        almost always is accompanied by absence of the hippocampal commissure (HC) although the anterior commissure (AC) is usually present and normal.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        In
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">partial posterior agenesis</inline>
        , the HC and posterior callosum (the splenium, with or without some involvement of the body) are both absent. In rare instances, the CC is completely absent but the HC is present. If all three commissures fail to develop at all, the result is termed
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">tricommissural agenesis</inline>
        .
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Etiology</fo:block>
       <fo:block text-align="justify" space-before="3pt">When the underlying mechanisms that regulate the guidance of commissural fibers fail, pathological dysgenesis of one or more commissures ensues. To date, nearly 40 genes have been linked to human callosal dysgenesis.</fo:block>
       <fo:block text-align="justify" space-before="6pt">CC anomalies can result from failure of axons themselves to form, failure of genetically-determined molecular guidance mechanisms, failure of the glial sling or hippocampal commissure to develop normally, or malfunction of these substrates in guiding axons to their proper destinations across the midline.</fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Pathology</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        In complete CC agenesis, no segments are present. Sagittal sections show an
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">absent cingulate gyrus</inline>
        while the hemispheres demonstrate a radiating
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">"spoke-wheel" gyral pattern</inline>
        extending perpendicularly to the roof of the third ventricle.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        On coronal sections the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">"high-riding" third ventricle</inline>
        looks as if it opens directly into the interhemispheric fissure but is actually covered by a thin membranous roof that bulges into the interhemispheric fissure, displacing the fornices laterally. The lateral ventricles have upturned, pointed corners.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">
        A prominent longitudinal WM tract called the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">Probst bundle</inline>
        is situated just inside the apex of each ventricle. These bundles consist of the misdirected commissural fibers that should have crossed the midline but instead course from front to back, indenting the medial walls of the lateral ventricles.
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">The septum pellucidum often appears to be absent but instead has widely separated leaves that course laterally--not vertically--from the fornices to the Probst bundles.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Axial sections show the lateral ventricles are parallel and nonconverging. The occipital horns are often disproportionately dilated, a condition termed colpocephaly.</fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Clinical Issues</fo:block>
       <fo:block text-align="justify" space-before="3pt" font-weight="normal" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Epidemiology and Demographics.</fo:inline>
        <fo:inline font-weight="normal">CC dysgenesis can be discovered at any age. It has a prevalence of at least 1:4,000 live births. CC dysgenesis is the most common CNS malformation and is found in 3-5% of individuals with neurodevelopmental disorders. Nonsyndromic CC dysgenesis has a slight male predominance.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Presentation.</fo:inline>
        <fo:inline font-weight="normal">MInor CC dysgenesis is often discovered incidentally on imaging studies or at autopsy. Major commissural malformations are associated with seizures, developmental delay, and symptoms secondary to disruptions of the hypothalamic-pituitary axis.</fo:inline>
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Imaging Findings</fo:block>
       <fo:block text-align="justify" space-before="3pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">CT Findings.</fo:inline>
        <fo:inline font-weight="normal">Axial NECT scans show parallel, nonconverging, widely separated lateral ventricles. Disproportionate enlargement of the occipital horns is common.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">MR Findings.</fo:inline>
        <fo:inline font-weight="normal">Sagittal T1- and T2WIs demonstrate partial dysgenesis or complete CC absence. With complete agenesis, the third ventricle appears continuous with the interhemispheric fissure and is surrounded dorsally by fingers of radiating gyri that "point" towards the third ventricle. In partial agenesis, the rostrum and splenium are often absent and the remaining genu and body have a "blocky" thickened appearance. The hippocampal commissure is typically absent but the AC may be preserved and often appears quite normal or even larger than usual.</fo:inline>
       </fo:block>
       <fo:block text-align="justify" space-before="6pt">A midline interhemispheric cyst may be present above the third ventricle. Such cysts can be a ventricular outpouching or separate structures that do not communicate with the ventricular system.</fo:block>
       <fo:block text-align="justify" space-before="6pt">An azygous anterior cerebral artery (ACA) can be seen "wandering" upwards in the interhemispheric fissure. Look for associated malformations of the eyes, hindbrain, and hypothalamic-pituitary axis.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Axial scans demonstrate the parallel lateral ventricles especially well. The prominent myelinated tracts of the Probst bundles can appear quite prominent.</fo:block>
       <fo:block text-align="justify" space-before="6pt">Coronal scans show a "Viking helmet" or "moose-head" appearance caused by the curved, upwardly pointed lateral ventricles and high-riding third ventricle that expands into the interhemispheric fissure. The Probst bundles are seen as densely myelinated tracts lying just inside the lateral ventricle bodies. The hippocampi appear abnormally rounded and vertically-oriented. Moderately enlarged temporal horns are common. Look for malformations such as heterotopic gray matter.</fo:block>
       <fo:block text-align="justify" space-before="6pt">DTI is especially helpful in depicting CC agenesis. The normal red (right-to-left encoded) color of the corpus callosum is absent. Instead, prominent front to back (green) tracts of the Probst bundles are seen.</fo:block>
       <fo:block text-align="justify" space-before="6pt" font-family="TimesNewRomanPSMT" font-size="10.5pt">
        <fo:inline font-family="Times-BoldSC">Angiography.</fo:inline>
        <fo:inline font-weight="normal">In complete CC agenesis, CTA, DSA, and MRA demonstrate an azygous ACA that courses directly upwards in the interhemispheric fissure.</fo:inline>
       </fo:block>
      </fo:block-container>
      <fo:block-container>
       <fo:block keep-with-next="always" space-before="9pt" margin-left="-15pt" font-weight="normal" font-family="TimesNewRomanPSMT" font-size="14pt">Differential Diagnosis</fo:block>
       <fo:block text-align="justify" space-before="3pt">
        The major differential diagnosis of CC dysgenesis is destruction caused by
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">trauma, surgery (callosotomy), or ischemia</inline>
        . Occasionally the
        <inline xmlns="http://www.w3.org/1999/XSL/Format" font-weight="bold">hippocampal commissure</inline>
        forms while the CC is absent and may mimic a remnant portion of the CC on sagittal images. Coronal views show the HC connects the fornices, not the hemispheres.
       </fo:block>
      </fo:block-container>
    </fo:block-container>
   </fo:block-container>
   <fo:block break-before="page" font-size="9pt">
    <fo:block keep-with-next="auto">
      <fo:block space-before="12pt" keep-with-next="always" margin-left="-15pt">
       <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
      </fo:block>
      <fo:block language="en" hyphenate="false" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-size="18pt">Selected References</fo:block>
      <fo:block space-before="12pt" keep-with-next="auto" margin-left="-15pt">
       <fo:leader leader-length="100%" rule-thickness="4pt" alignment-baseline="before-edge" color="#2F4886" leader-pattern="rule" />
      </fo:block>
    </fo:block>
    <fo:block language="en" hyphenate="false" color="#2F4886" margin-left="-15pt" keep-with-next="always" space-before="12pt" font-style="italic" font-size="16pt">Normal Development and Anatomy of the Cerebral Commissures</fo:block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Normal Development</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Barkovich AJ et al: Congenital malformations of the brain and skull. In X Y (et al): Pediatric Neuroimaging. 5th ed. Philadelphia: Lippincott Williams &amp; Wilkins. 368-83, 2012; name of general editor(s) missing from this cite. I also suspect the pub date is 2011 rather than 2012, but not sure. Pretty sure the full cite for this book exists elsewhere in this book; find it and match it.</fo:block>
        </fo:list-item-body>
       </fo:list-item>
      </fo:list-block>
    </fo:block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Normal Gross and Imaging Anatomy</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Peltier J et al: Microsurgical anatomy of the anterior commissure: correlations with diffusion tensor imaging fiber tracking and clinical relevance. Neurosurgery. 69(2 Suppl Operative):241-6; discussion 246-7, 2011</fo:block>
        </fo:list-item-body>
       </fo:list-item>
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Wang F et al: Microsurgical and tractographic anatomical study of insular and transsylvian transinsular approach. Neurol Sci. 32(5):865-74, 2011</fo:block>
        </fo:list-item-body>
       </fo:list-item>
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Patel MD et al: Distribution and fibre field similarity mapping of the human anterior commissure fibres by diffusion tensor imaging. MAGMA. 23(5-6):399-408, 2010</fo:block>
        </fo:list-item-body>
       </fo:list-item>
      </fo:list-block>
    </fo:block>
    <fo:block language="en" hyphenate="false" color="#2F4886" margin-left="-15pt" keep-with-next="auto" space-before="12pt" font-style="italic" font-size="16pt">Commissural Anomalies</fo:block>
    <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
      <fo:list-item space-before="3pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block>Barkovich AJ: Congenital malformations overview. In Osborn AG et al: Diagnostic Imaging: Brain. 2nd ed. Salt Lake City: Amirsys. I-1-2 to I-1-5, 2010</fo:block>
       </fo:list-item-body>
      </fo:list-item>
      <fo:list-item space-before="3pt">
       <fo:list-item-label end-indent="label-end()">
        <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
       </fo:list-item-label>
       <fo:list-item-body start-indent="body-start()">
        <fo:block>Ren T et al: Imaging, anatomical, and molecular analysis of callosal formation in the developing human fetal brain. Anat Rec A Discov Mol Cell Evol Biol. 288(2):191-204, 2006</fo:block>
       </fo:list-item-body>
      </fo:list-item>
    </fo:list-block>
    <fo:block keep-with-next="always" space-before="6pt" font-style="normal" font-size="14pt">Callosal Dysgenesis Spectrum</fo:block>
    <fo:block space-before="5pt" font-size="9pt" font-style="normal">
      <fo:list-block provisional-label-separation="3pt" provisional-distance-between-starts="0.15in">
       <fo:list-item space-before="3pt">
        <fo:list-item-label end-indent="label-end()">
          <fo:block font-size="9pt" font-family="TimesNewRomanPSMT">•</fo:block>
        </fo:list-item-label>
        <fo:list-item-body start-indent="body-start()">
          <fo:block>Paul LK: Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement. J Neurodev Disord. 3(1):3-27, 2011</fo:block>
        </fo:list-item-body>
       </fo:list-item>
      </fo:list-block>
    </fo:block>
   </fo:block>
  </fo:flow>
</fo:page-sequence>
</fo:root>



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