Nasal dermoid sinus cyst with intracranial extension and atretic sinus tract in an adult patient

Nasal dermoid sinus cyst (NDSC) is a rare congenital lesion due to cephalic neural tube defect. It may also have been seen in other parts of the body. NDSC constitutes 1–3% of all dermoid cysts and 11–12% of those in the head and neck. A NDSC is located in the median line of the nasofrontal region from the glabella to the columella. The differential diagnosis based on location includes epidermal inclusion cyst, glioma, meningomyelocele, meningoencephalocele, teratoma, teratoid cyst, thyroglossal duct cyst, branchial cleft cyst, and benign lymphadenopathy. Intracranial extension causes serious complications such as meningitis, osteomyelitis, abscess formation, hydrocephalus, seizures, and personality changes. All patients with NDSC should be considered to have a potential intracranial extension and should, therefore, undergo pre-operative radiological evaluation. Herein, the authors report an unusual adult patient with NDSC with intracranial extension.