The prenatal diagnosis for absence of fetal cavum septum pellucidum by ultrasonography / 中华医学超声杂志（电子版）

ABSTRACT

Objective To explore the clinical significance of prenatal diagnosis for absence of fetal cavum septum pellucidum (CSP) by ultrasonography. Methods The ultrasonographic characteristics were retrospectively analyzed in 63 fetuses, whose CSPs were not detected in prenatal two and three dimensional ultrasonography in Nanjing Medical University Affiliated Suzhou Hospital. Results In 63 fetuses with absent CSP, the related malformations included:(1) Five cases were diagnosed as agenesis of corpus callosum (ACC, including four complete ACC and one partial ACC);(2) Twenty-seven cases were diagnosed as holoprosencephaly (HPE, including 18 alobar HPE, ifve semilobar HPE and four lobar HPE);(3) One case was diagnosed as schizencephaly;(4) Two cases were diagnosed as porencephaly;(5) Five cases were diagnosed as hydranencephaly;(6) Twenty-three cases were diagnosed as severe hydrocephalus, among which ifve cases were caused by aqueductal stenosis and the other 18 cases were caused by open spina biifda (Chiari Ⅱ malformation). These absent CSP fetuses had other abnormalities including one case of Dandy-Walker Malformation, one case of Dandy-Walker Variation, 14 cases of median cleft lip, ifve cases of single naris, two cases of proboscis nose, three cases of talipes foot and four cases of single umbilical artery, etc. These 63 cases were all followed up after prenatal ultrasonography but 4 cases were missed and one case of septo-optic dysplasia was misdiagnosed as lobar HPE. The diagnoses of other 58 fetuses by ultrasonography were conifrmed by follow up. Conclusions CSP is considered as an essential part in prenatal evaluations of the fetal central nervous system during second-and third-trimester. Absence of CSP is always accompanied with an extremely wide spectrum of fetal neuroanatomic malformations, including prosencephalon diseases, intracranial midline anomalies, etc. Prenatal ultrasonography is the best choice for the observation of CSP.