Large transethmoidal meningoencephalocele in a neonate involving three discrete defects in lamina cribriform: A case report

Intranasal meningoencephaloceles are rarely encountered in pediatric neurosurgery. The symptoms and clinical features may mimic those of nasal polyps or dermoid cysts. Transethmoidal meningoencephalocele is a rare congenital meningoencephalocele of the anterior skull base with diverse clinical presentation. The appropriate surgical intervention is chosen according to the meningoencephalocele type and location. Radiological examinations such as computed tomography and magnetic resonance imaging are helpful for the differential diagnosis of the encephalocele sac and localization of the cranial bone defect. We are reporting a case of basal meningoencephalocele of the transethmoidal type, which was discovered in a 20-day-old boy presenting with cerebrospinal fluid rhinorrhea, respiratory distress, difficulty in feeding, and meningitis. The preoperative images showed a large herniated intranasal sac with bony discontinuity of the cribriform plate; however, three discrete defects of the cribriform plate with their related discrete herniated sacs were identified intraoperatively. Two staged surgeries were performed in succession: transcranial to separate the sacs from the cranial cavity and seal the anterior fossa floor, followed by transnasal to remove the remnant of the intranasal sacs. Patient symptoms and signs markedly improved after the surgeries. We highlight the need for urgent intervention at a very young age if the clinical presentation mandates, and also the importance of meticulous intraoperative identification of all bony and dural defects that might be missed in preoperative images to ensure complete repair and prevent recurrence.