Clinical Study of the Central Nervous System Anomalies by Antenatal Ultrasonography / 대한주산의학회잡지

ABSTRACT

OBJECTIVE: To determine the proportion and the types of CNS anomalies among congenital anomalies detected through prenatal ultrasonography. MATERIALS AND METHODS: Between November 1997 and December 2000, 624 cases of singleton pregnancies were terminated at Department of Obstetrics and Gynecology, CHA Hospital due to lethal congenital anomalies detected through prenatal ultrasound. Forty-three of 624 termination cases had CNS anomalies. Autopsy and chromosomal study was carried out on ten and six cases respectively. Incidence, maternal age and parity, sex ratio and body weight of the terminated fetuses, gestational age at which anomaly was detected, associated anomalies were evaluated. RESULTS: The incidence of CNS anomalies was 0.21%(43 in 20,805), and maternal age was between 30 and 34 in 20cases. The fetus was male in 25 cases, female in 11 cases and indefinite in 7 cases. Anomalies were detected between 17-20 weeks in 12 cases. Body weights of the terminated fetuses were below 500grams in 23 cases. Anencephaly was the most common with 11 cases(25.6%), hydrocephalus ranked second with 8 cases(18.6%). Two cases had associated anomalies of Meckel-Gruber syndrome features. CONCLUSION: CNS anomalies are frequent and have a severe prognosis. Contemporary ultrasound is much accurate in evaluating CNS anomalies. Still, minor anomalies and those cases without associated anomalies are difficult to detect. Even after diagnosis, CNS anomalies are mostly void of prenatal corrective treatment. Fortuitous investigation is needed for prenatal neural axis anomaly detection.