Prenatal diagnosis in three cases of iniencephaly with unusual postmortem findings

Congenital central nervous system anomalies: Ten-year single center experience on a challenging issue in perinatal medicine

Objective

Our goal was to highlight the prenatal diagnosis and management of central nervous system (CNS) anomalies through sharing our clinic’s experience.

Material and Methods

We evaluated prenatal findings and postnatal outcomes of neonates who had a CNS anomaly diagnosis in our clinic over a ten-year period. A total of 183 cases with various CNS anomalies were included in the study. Birth or termination preferences of mothers were recorded in all cases, and postnatal diagnosis concordance and prognosis after surgical procedures were evaluated in mothers who chose to continue the pregnancy.

Results

The mean maternal age was 28.2±5.5 years, mean gravida was 2.2±1.3, and the mean gestational age at diagnosis was 30.5±5.5 weeks. Seventy-five out of 183 (41%) patients chose to terminate their pregnancy. Twenty babies (26.6%) in the termination of pregnancy group had additional anomalies. One hundred eight patients gave birth at our institution. The mean birth weight was 3060±647.5 g, the mean gestational week at delivery was 37.9±1.7 weeks, and mean APGAR score (5th minute) was 8.8±2.3. Four neonates died on the postpartum first day. The postnatal diagnosis of 60 of the 108 (55.5%) patients who gave birth was concordant with the prenatal diagnosis, and 32 of the 108 (29.6%) babies underwent surgical interventions.

Conclusion

CNS anomalies have a broad spectrum and variable prognoses. This study highlights the limitations of prenatal diagnoses, and the need for parents to have this information in order to determine the course of their pregnancy and prepare themselves for the postnatal challenging treatment/rehabilitation process.

Surgical Outcome in an Iniencephaly Survivor: Case Report and Review of the Literature

BACKGROUND

Iniencephaly is an extremely rare congenital neural tube defect (NTD) involving the occipital region with rachischisis of the cervicothoracic spine and fixed retroflexion deformity of the head. It affects an estimated 0.1-10 out of 10,000 pregnancies and carries a dismal prognosis. Most affected children are either stillborn or perish within a few hours of delivery. Pathological and postmortem studies of iniencephaly significantly outnumber the limited amount of literature available on patients surviving with this disorder. To date, surgical repair has been attempted in only 3 of the 8 patients with iniencephaly who have survived long-term. Thus, a huge knowledge gap remains regarding the neurosurgical nuances and postsurgical outcomes in iniencephaly.

CASE DESCRIPTION

A 4-year-old girl presented with soft, fluctuant swelling in the suboccipital region and was subsequently diagnosed with iniencephaly. She underwent a successful surgical repair of the encephalocele with dural plication. No recurrence of swelling or new neurologic deficits were noted at a 1-year follow-up.

CONCLUSION

Iniencephaly is a complex NTD associated with high perinatal mortality that requires a vigilant antenatal diagnosis. Surgical repair may be attempted in the lucky few survivors after a thorough evaluation of the anomaly.

Iniencephaly: a rare congenital anomaly reaching the term

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.

Iniencephaly: Radiological and pathological features of a series of three cases

Iniencephaly is a rare form of neural tube defect with an incidence of 0.1-10 in 10,000 pregnancies. It is characterized by the presence of occipital bone defects at foramen magnum, fixed retroflexion of head, spinal dysmorphism, and lordosis of cervicothoracic vertebrae. It is usually associated with central nervous system, gastrointestinal, and cardiovascular anomalies. We present radiological and autopsy findings in a series of 3 cases of iniencephaly (gestational ages 29.3, 23, and 24 weeks) first fetus in addition showed omphalocele, pulmonary hypoplasia, two lobes in right lung, accessory spleen, atrial septal defect, bilateral clubfoot, ambiguous genitalia, and single umbilical artery. Second fetus was a classical case of iniencephaly apertus with spina bifida. Third fetus had colpocephaly and bifid spine.

Iniencephaly clausus: A case report with review of literature

Iniencephaly is a rare neural tube defect characterized by extreme retroflexion of the head with the absence of neck due to spinal deformities. The important features that help us to diagnose a case of iniencephaly are occipital bone deficit leading to enlarged foramen magnum, fusion of malformed cervical and thoracic vertebrae, and upward turned face with chin continuous with chest because of the absence of neck. The differential diagnoses include anencephaly with spinal retroflexion, Klippel–Fiel syndrome, nuchal tumors such as teratoma, goiter, and lymphangioma and Jarcho–Levin syndrome. Previously many case reports on radiological features of iniencephaly are published, but there are very few articles on necropsy findings and differential diagnosis. In the present case we have discussed in detail the necropsy findings of iniencephaly clausus with special reference to differential diagnosis.

Major diagnostic and pathological features of iniencephaly based on twenty-four cases

Iniencephaly is quite a rare malformation the etiology of which is still not fully understood. In the majority of cases it is a grave and lethal condition. It is often complicated by other abnormalities affecting the central nervous system (spina bifida, anencephaly), but malformations involving other organs and systems may also be observed. Based on 24 cases the authors have surveyed the diagnostics of iniencephaly with special regard to the disorders affecting the central and non-central nervous systems. In addition, they have compared the results of prenatal diagnostics and pathological investigations. In the sample, maternal age ranged between 17 and 42 (median 24) years. Positive obstetrical-gynecological and genetic findings in the patients' history have been reported in 4 and 2 cases, respectively. In these cases, the maternal serum alpha-fetoprotein (AFP) values ranged between 0.7 and 3.9 (median 2.0) MoM, while the amniotic fluid AFP values were between 0.9 and 2.7 (median 1.4) MoM. Spina bifida (50%) and anencephaly (42%) were the most commonly occurring complications affecting the central nervous system. Among the non-central nervous system disorders, malformations of the abdominal (omphalocele) and thoracic walls (diaphragmatic hernia) were found most frequently and the tendency to develop associated polyhydramnios was also very high (75%). Pathological investigations revealed developmental disorders such as cleft lip and palate, ventricular septal defect and facial dysmorphism, which are difficult to detect using ultrasonography.

Iniencephaly: Prenatal diagnosis with postmortem findings

Iniencephaly is a rare but almost always lethal neural tube defect with the following cardinal features: occipital bone defect, partial or total absence of cervicothoracal vertebrae and fetal retroflexion. Iniencephaly is associated with malformations of the central nervous system, gastrointestinal and cardiovascular system. Prenatally diagnosed cases of iniencephaly are rare because careful and early ultrasonographic evaluation is necessary. The present cases of iniencephaly were found to carry associated malformations such as atrioventricular septal defect and club foot. We present an iniencephaly prenatally diagnosed by sonography, in which therapeutic abortion was induced, with a review of the published literature.