Intracranial translucency as a sonographic marker for detecting open spina bifida in the first trimester

Background and objective: Neural tube defect is a serious congenital anomaly associated with lifelong disability, mortality and morbidity; it consists of heterogeneous group of disorders affecting brain and spinal cord. This study aimed to test the efficacy and accuracy of the intracranial translucency (fourth ventricle) in diagnosing open spina bifida. Methods: A diagnostic prospective convenient study of intracranial translucency and open spina bifida was conducted in the Maternity Teaching Hospital / Erbil city, Kurdistan region /Iraq from the Feb 2021 till June 2022. The study included 200 pregnant women attended maternity teaching hospital for routine first trimester scan (11 wk -13 wk+6d) using a convenience method. Ultrasound examinations were performed using general electric (GE) ultrasound machine. The fetuses were classified into two groups; those fetuses which have clear visible intracranial translucency on ultrasound examination by the radiologist, and in the other group, the intracranial translucency was not clearly seen. Results: The two studied groups were comparable in crown-rump length, number of pregnancies, number of children, maternal age, and maternal weight. Intracranial translucency was seen in 196 out of 200 (98%) and was not visible in 4 cases out of 200 (2%). Conclusion: The intracranial translucency was considered a good sonographic marker with high accuracy and sensitivity in diagnosing cases of OSB among 11-13+6 weeks pregnant women.