A singular case of frontal meningoencephalocele associated a with Lhermitte-Duclos syndrome

Meningoencephalocele (MEC) refers to a herniation of intracranial contents, through a defect of the skull base into the nasal or paranasal cavities. It is a rare entity, typically congenital, originating from a defect during or immediately after the neurulation process. Less frequently it can be secondary, especially in adults as in the present case, resulting from traumatic injuries, surgery, hydrocephalus, and chronic sinusitis. Diagnosis is based on clinical evaluation, CT (computed tomography) scans and MRI (magnetic resonance imaging). B2-transferrin dosage may be useful in unclear cases. The clinical case herein presented refers to an unusual presentation of a MEC in the frontal sinus associated with Lhermitte-Duclos Syndrome, a condition which led over time to hydrocephalus and intracranial hypertension, well-known predisposing factors for MEC genesis. A combined transnasal endoscopic and external approach was performed to completely dominate the herniation and adequately reconstruct the bony defect with a gasket seal technique. To date, the patient has no recurrence of MEC.