Parietal Cranium Bifidum: A Rare Presentation

Aim: To enlighten the readers regarding rare and distinct presentation of fetal encephalocele in parietal location and its significance. Background: Cranium bifidum is a defect in the cranium through which there can be herniation of intracranial contents. If the content of herniation is meninges, it is called meningocele and if it contains brain tissue in addition to meninges, it is called meningoencephalocele or encephalocele. The incidence of encephalocele is 1 in 4,000 live births. The most common location is the occipital region (75%) followed by frontoethmoidal (15%), which is common in Asian population, and rarest is the basal followed by parietal locations. The exact incidence of parietal encephalocele is not available due to its rarity. Case report: We present a case of a 24-year-old primigravida female in second trimester who came for antenatal scan to rule out anomalies. On examination by ultrasonography, we found a large cerebriform soft tissue herniating through a defect in skull vault from the vertex region with secondary microcephaly. Conclusion: Here we give an overview of rarest form of encephalocele in parietal region, which grossly differs from the already reported parietal encephaloceles of atretic type presenting as small skin-covered subscalp lesions that contain Meninges and neural and glial rests. In our case, the encephalocele was distinct, being larger in size with normal brain parenchyma as the major content of the herniating sac. Clinical significance: Only few cases of parietal encephalocele is reported in the literature, that too of atretic type. Apart from being the rarest form, this variant is found to be associated with poor prognosis.