Iniencephaly: a rare congenital anomaly reaching the term

Abstract

Abstract Introduction Iniencephaly is characterized by a defect in the occipital bone in the inion, occipital encephalocele, spinal dysraphism and fixed hyperextension of the fetal head. The associated anomalies are observed in many systems including the central nervous system and the gastrointestinal system. Prenatal diagnosis is rare because early and careful ultrasonographic evaluation is necessary. Fetuses with iniencephaly are almost always stillborn. We aimed to present a fetus with iniencephaly reaching term in utero. Case A 25-year-old healthy primigravida Syrian woman consulted with labor pain at 39 weeks of gestation. She had no laboratory tests or ultrasonographic examination during the pregnancy. Ultrasound evaluation demonstrated a single live intrauterine fetus with a retroflexed fetal head and excess amniotic fluid. A girl was delivered by cesarean section weighing 3350 g with a length of 48 cm. The fetal head was retroflexed with an occipital bone defect. Associated anomalies such as club foot were also observed (Figures 1 and 2). Discussion Iniencephaly is an extremely rare neural tube defect first described by Saint-Hilare in 1836. Its incidence varies from 0.1 to 10 : 10,000. The incidence is higher in families with a history of neural tube defect. Maternal drug use, smoking, alcohol use, low parity and low socioeconomic status are risk factors. Prenatal diagnosis is possible by careful and early ultrasonographic examination. Termination of pregnancy is the generally accepted approach in these pregnancies because of poor prognosis and severe mortality. The most important precaution is to prevent obstructed labor and maternal trauma due to corporal distortion of the fetus.