Nasal dermoid cysts with intracranial extension: avoiding coronal incision through midline exposure and nasal bone osteotomy.

OBJECTIVE: Up to 10% of midline nasal dermoid cysts have intracranial extension. Previous techniques of excision include frontal and frontonasal craniotomies via a coronal approach, combined with a direct cutaneous excision of the dermoid cyst. While the coronal incision allows for wide visualization, it carries significant risks of transfusion, blood loss, and scarring. The authors present an alternative technique in which access is gained through a midline extension of the dermoid cyst excision that provides direct access for a keyhole frontal craniotomy.

METHODS: The authors utilize a nasal bone osteotomy, pericranial flap, and keyhole-type craniotomy performed through a nasal midline incision for the treatment of nasal dermoid cysts with intracranial extension. They performed a retrospective chart review of all patients with nasal dermoid cysts treated at the Ann & Robert H. Lurie Children's Hospital of Chicago from 2009 to 2017. Patient demographic data, operative data, and in- and outpatient complication data were collected.

RESULTS: In 10 patients with cyst extension near or into the intracranial cavity (7 with true intracranial extension), the nasal osteotomy technique was performed. The mean blood loss was 13 ml, with a 0% transfusion rate. The mean length of inpatient stay was 1 day. A durotomy was made and repaired as part of the dermoid cyst dissection in 3 patients. One patient underwent intraoperative placement of a lumbar drain. The mean operative time was 228 minutes. There were no intraoperative or postoperative complications, including the need for a reoperation. No patients had any long-term complications, and no patients have had dermoid cyst recurrence. The appearance of the scar was acceptable in all cases.

CONCLUSIONS: The midline approach to nasal dermoid cysts with intracranial extension is safe and results in limited blood loss, short operative times, and short lengths of inpatient hospital stay. This is a viable technique for the treatment of this challenging pathology.