Open Access Atlas of Otolaryngology, Head & Neck Operative Surgery Surgery for Nasal Dermoids

Midline masses are rare congenital anomalies, with an incidence reported to be between 1 in 20,000 to 1 in 40,000 live births. Nasal dermoid cysts are the most common of the congenital midline nasal masses, a group that also includes nasal gliomas and encephalocoeles, and much less frequently haemangiomas, lipomas, lymphangiomas and other very rare lesions. Cases are usually sporadic, but rare familial series have been reported. They are distinguished by the tissues of origin, with dermoids developing from trapped ectoderm and mesoderm; hence they may contain adnexal structures such as skin, hair follicles and sebaceous glands. By contrast, encephalocoeles are herniations of the meninges, and may also contain brain tissue, while gliomas contain glial cells.