Click on image to view larger version.
FIG 3. A, Sagittal spine and B, axial brain MR images in a 20-week fetus after a therapeutic abortion because of a sonographic diagnosis of myelomeningocele and Chiari II malformation. These findings were confirmed with postmortem MR imaging and autopsy. The spine MR image (A) shows a low thoracic myelomeningocele with an adjacent complicated fusion defect of the lower thoracic-upper lumbar vertebral bodies. There is also extensive syringohydromyelia. The cerebellar tonsils (arrow) are abnormally low (at C3), indicating a Chiari II abnormality, and images of the brain (not shown) confirmed the presence of a small posterior fossa. This brain MR image (B) shows ventriculomegaly and the "lemon-shaped" deformity recognized on sonograms in cases such as these.
