Prenatal diagnosis of intracranial lipoma associated with agenesis of the corpus callosum.

BACKGROUND: Lipoma of the corpus callosum is a congenital malformation present in 1:1700 individuals. Only three cases of prenatal sonographic diagnosis have been described. CASES: Two cases of prenatal sonographic diagnosis of intracranial lipoma are described. The first case was visible at 26 weeks' gestation and was associated with partial agenesis of the corpus callosum, a characteristic midline gyral pattern, and fetal colpocephaly. The second case was an isolated lipoma diagnosed at 37 weeks. In both cases transvaginal scanning and color Doppler studies were useful adjuncts in making the diagnosis.
CONCLUSION: Prenatal sonographic diagnosis of intracranial lipoma associated with agenesis of the corpus callosum is possible as early as 26 weeks' gestation. Because prognosis depends on associated anomalies, a detailed examination of fetal intracranial anatomy and a complete anatomic survey should be performed. Awareness of this lesion can be expected to increase its detection on prenatal sonography.