OCCIPITAL ENCEPHALOCELE

• Most common type in the Western hemisphere.
• Supra and infratentorial structures involved with equal frequency.
• Ventriculocele - cyst within a cyst due to herniation of the fourth ventricle into the cephalocele.

DIFFERENTIAL DIAGNOSIS

Occipital encephalocele	Cystic hygroma
May have strands of neural tissue that may mimic a septum.	Septae present. Ligamentum nuchae.
Acute angle with the surface as it protrudes through a defect.	Obtuse angle with respect to the fetal head surface as it arises beneath the skin surface.
Intracranial abnormality present:   - Microcephaly.   - Ventriculomegaly.   - Lemon skull.   - Beaked tectal plate.   - Flat occiput.	No intracranial abnormality.