Diagnostic anténatal d’un rachischisis

We report the case of a 30-year old G1P0 patient, referred to our Prenatal Diagnostic Unit due to the suspicion of open spina bifida at 24 w + 2d of pregnancy. The reassessed first-trimester ultrasound did not meet the quality standards for early diagnosis. The patient hadn’t undergone prescribed first trimester serum markers screening. Morphology ultrasound showed biparietal diameter smaller than the 3rd percentile associated with temporal bone depression (A), lack of visualization of the large cisterna, Chiari malformation type II with the cerebellum protruding into the posterior fossa (B) and abnormal closure of the neural tube similar to rachischisis (C). Three-dimensional ultrasound was performed to visualize the extended dorsolumbar defect (D); the persistence of lower limb movements were deemed satisfactory. After the couple was informed about the poor prognosis of the abnormal ultrasound signs, they decided to interrupt the pregnancy (E) after investigating the karyotype of amniotic fluid cells. Chromosomal formula was normal: 46, XY. Upon discharge, the patient was prescribed folic acid supplements.