Anterior encephaloceles: a study of 92 cases

Anterior encephalocele is a rare condition, and only a few large series have been published in the literature. Surprisingly, the incidence is much higher in Southeast Asian countries, including some parts of India. While the reported incidence in the West is between 1:35,000 and 1:40,000 live births, it is as high as 1:5,000 live births in Thailand. We present a series comprising 92 cases of anterior encephaloceles treated over a 30-year period (1971-2000). Frontoethmoidal encephaloceles are the commonest type, followed by the nasopharyngeal and orbital type. Among the frontoethmoidal encephaloceles, nasoethmoid is the commonest type, and these patients present with swelling over the bridge of the nose with significant hypertelorism and orbital deformities. The nasopharyngeal type remains occult and presents with nasal obstruction or CSF rhinorrhea. Rarely, the patient may present with meningitis. Since 1978, computed tomography (CT) scans have regularly been performed in our patients. CT scans delineate the skull defect and associated brain anomalies. There was associated hydrocephalus present in 12 patients and agenesis of the corpus callosum in 5 patients. In all patients, one-stage repair of the encephalocele and correction of bony anomalies by appropriate osteotomy was undertaken. Since 1988, in cases of frontoethmoidal encephalocele with significant hypertelorism, medial advancement of the medial half of the orbits on either sides was carried out, instead of a classical Tessier's operation. Postoperative morbidity included CSF leak in 20 patients, wound infection in 2 and chest infection in 3. There were 3 deaths in our study. The overall cosmetic outcome was good.