Obstetric gynecology service I -CHU Hassan II Fez Morroco

Case report

A 28-year-old woman (G1P0) with first degree consanguinity, was sent to our unit for management the risk of premature birth at 34 weeks of pregnancy. Ultrasonography revealed an encephalocele containing mixed cystic and solid mass. The evolution was marked by a premature birth of a newborn of 2100 gr with an encephalocele associated to omphalocele who died after 30 min of life.

Images 1, 2 and 3: 2D ultrasound images revealed a large occipital encephalocele confirmed after birth in image 3.

Definition

Herniation of intracranial structures through skull defect.

Pathogenesis.

Several proposed mechanisms.

• Primary failure of cranial neuropore closure.
• Secondary event with pressure erosion and herniation of neural tissue.
• Failure of induction of membranous bone formation.

Diagnosis and sonographic findings

In the first trimester, we must do endovaginal examination to see the cranial defect.

In the second or third trimester we can see: herniation of mixed cystic and solid mass, normal intracranial landmarks distorted, ventriculomegaly, neuronal migrational anomalies, spina bifida and others anomalies.

The osseous defect is usually midline in the occipital bone.

Differential diagnosis

Scalp masses, cystic hygroma, amniotic band syndrome.

Associated anomalies

Meckel-Gruber syndrome, Walker-Warburg syndrome, Knobloch syndrome.

Prognosis

Varies with amount of brain tissue in defect and associated malformations.

Management

Referral to neurosurgery prior to delivery for surgical planning. Cesarean section considered to reduce birth trauma.

References

1. Haberle J et al : cervical encephalocele in a newborn. Case report and review of the literature. Childs nerv syst. 17(6) :373-5,2001
2. Kojima K et al : antenatal evaluation of an encephalocele in imaging. Fetal Diagn Ther.18(5) :338-41,2003
3. Bannister CM et al : Can prognostic indicators be identified in a fetus with an encephalocele ? Eur J Pediatr Surg 10 Suppl. 1 :20-3,2000