Iniencephaly: prenatal diagnosis and management

Abstract

Iniencephaly is a rare malformation characterized by the triad of occipital bone defect, cervical dysraphism and fixed retroflexion of the fetal head. Because of its almost invariable lethal prognosis, termination of pregnancy is commonplace when this condition is diagnosed before viability. In this report we describe eight cases of iniencephaly prenatally diagnosed by ultrasound between 18 and 28 weeks of gestation and discuss the subsequent obstetric management in a country where elective abortion is illegal. Prenatal karyotyping was performed in seven cases, revealing a normal complement in all fetuses. One pregnancy miscarried at 24 weeks. Uneventful vaginal delivery was accomplished in six of the remaining seven cases, one delivered spontaneously at 29 weeks and five were induced between 28-32 weeks due to increasing polyhydramnios. In the remaining case the pregnancy progressed to 35 weeks, at which time spontaneous labour began and an emergency Caesarean section was performed because of malpresentation. There were no survivors in this series. We conclude that, in countries were elective abortion is not allowed, women carrying an iniencephalic fetus may benefit from preterm induction of labour in order to avoid labour dystocia, maternal trauma during delivery and the risks of a Caesarean section.

Newborn with meroanencephaly: Surviving all odds

“…In addition, iniencephalocele is another differential characterized by a triad of the occipital bone defect, rachischisis, and fixed retroflexion of the head with severe cervicothoracic lordosis. [7]…”

Late diagnosis iniencephaly with spina bifida

“…[6][7][8][9][10] Sonographic diagnosis based on the extreme dorsal flexion of the head, the unusually short and deformed cervical and thoracic spine, and overall fetal shortening. The head retroflexion and spinal disorganization are visible on medial-sagittal scans of the spinal column.…”

Iniencephaly: Prenatal diagnosis with postmortem findings

“…The prenatal diagnosis of iniencephaly can be made by ultrasound as has been demonstrated by several authors. Ultrasound evaluation should include a sagittal section through the spine for accurate evaluation of vertebral anomalies with obsevation of the occipital bone and foramen magnum 9 . The key diagnostic features include exaggerated lordosis, rachischisis, imperfect formation of skull base at foramen magnum, with variable amounts of fusion of inion with cervico thoracic spine and resultant severe dorsilexion of head.…”