Indirect ultrasonic signs of the callosal partial agenesis and hypoplasia in the fetus / 实用医学杂志

ABSTRACT

Objective To investigate antenatal sonographic findings of the fetal isolated callosal hypoplasia and partial agenesis. Methods A retrospective study was performed on the cases of hypoplasia and partial agenesis of the corpus callosum suspected at antenatal sonographic basic examination from 2006 to 2014, all the cases were confirmed by pathology or magnetic resonance imaging(MRI). For the surviving infants, clinical follow-up had been performed to assess the developmental outcome. Results Thirteen fetuses suspected with callosal underdevelopment were identified at a median gestational age of 31 (range, 18~39) weeks. Ten cases were confirmed by autopsy and MRI, including 9 with partial agenesis and 1 with hypoplasia. Among the 10 fetuses confirmed with isolated partial agenesis or with hypoplasia, incidence of the absent cavum septum pellucidum was 20%, the ‘Tear-drop’ lateral ventricles was 40%, the upward displacement of the third ventricle was 80%. Pregnancy was terminated electively in 8 of the cases with partial agenesis or with hypoplasia. Among the 2 surviving infants, apparent normal development was observed in only one case, but we lost the follow-up of this case at two-year-old. Six fetuses received the chromosome identification, almost all of them were normal. Conclusion The basic ultrasonic examination is feasible for the antenatal diagnosis of isolated callosal underdevelopment the. The indirect classical signs of callosal partial agenesis and hypoplasia are different with those of complete agenesis of the corpus callosum. The incidences of the‘Tear-drop’ lateral ventricles and the upward displacement of the third ventricle are higher than the absence of CSP. The chromosome of isolated callosal partial agenesis or hypoplasia is normal, however, the prognosis is uncertain.