[Prenatal MRI of corpus callosum agenesis. Study of 20 cases with neuropathological correlations].

Twenty prenatal MR studies of corpus callosum agenesis were retrospectively studied and compared with neuropathologic examinations (18) or postnatal imaging (2). Corpus callosum agenesis were either complete (14) or partial (6). Positive diagnosis was made in 19 cases/20. The diagnosis of "isolated" or "associated" corpus callosum agenesis was assessed in 11 cases/15. MR depicted 15 of the 33 associated neurologic abnormalities. Prenatal MR is a valuable complementary technique for the diagnosis of corpus callosum agenesis when sonography is doubtful. MR could improve prognosis evaluation, since it enables depiction of associated abnormalities, notably gyral abnormalities, posterior fossa malformations, and intra-cranial cysts. MR images prove to be useful before neuropathologic examinations.