A Unique Case of Frontotemporal Dermoid Cyst Presenting as Orbital Cellulitis.

Dermoid cysts are benign developmental anomalies that can occur anywhere along the neuroaxis or embryonic lines of fusion. While intracranial dermoid cysts at the midline frequently have an associated nasal or subcutaneous sinus tract, it is quite rare to encounter an intracranial dermoid cyst off the midline with a lateral sinus tract. Standard practice for the treatment of dermoid cysts is surgical resection to minimize the risks of meningitis, abscess, mass effect, neurologic deficit, and/or death.  A 3-year-old male with a history of DiGeorge syndrome presented with right orbital cellulitis and a right-sided dermal pit. Computed Tomography (CT) imaging demonstrated a dermal sinus tract with an associated lytic bone lesion within the right sphenoid wing and posterolateral orbital wall with intracranial extension. The patient was taken to the operating room in conjunction with plastic surgery for resection of the dermal sinus tract and intraosseous dermoid.  This case presents a rare occurrence of a non-midline, frontotemporal dermal sinus tract associated with a dermoid cyst with intracranial extension presenting with pre- and post-septal orbital cellulitis. Important considerations include preservation of the frontal branch of the facial nerve, preservation of orbital structure and volume, complete surgical resection to prevent infectious complications including meningitis, and a multidisciplinary surgical approach with plastic surgery, ophthalmology, and/or otolaryngology.