Transnasal Endoscopic Approach for Excision of Intracranial Nasal Dermoid Sinus Cysts.

Objective: Nasal dermoid sinus cysts (NDSCs) with intracranial extension in the form of dermal sinus tracts require careful and complete resection to prevent recurrence. Resection techniques necessitate adequate intracranial exposure, but morbidity associated with historical resection approaches has presented unique multidisciplinary challenges for surgeons treating cysts with intracranial extension.

Methods: The authors primarily employed a transnasal approach through a midline nasal incision, utilizing endoscopic or microscopic access between the lateral cartilages for resection of NDSCs with intracranial extension. A retrospective review was completed for patients treated for NDSCs at the authors' pediatric quaternary referral center from 2017 to 2023. Data collection included demographics, comorbidities, perioperative data, pre and postoperative imaging, surgical outcomes, and complications.

Results: Eighteen patients with NDSCs with possible or confirmed intracranial extension were surgically treated from 2017 to 2023. Fifteen were treated with resection performed through a midline transnasal approach with endoscopic assistance, achieving successful total resection while avoiding nasal osteotomy or frontal craniotomy. One patient had a slow cerebrospinal fluid leak from an operative durotomy, successfully treated with a lumbar drain. No other complications occurred. No patients required transfusion. Incision length and postoperative scar burden were less than approaches that used osteotomies or craniotomies and demonstrated excellent cosmetic results. No patients have had cyst recurrence or required reoperation.

Conclusions: A transnasal approach through a midline incision with endoscopic assistance is an effective approach for resection of NDSC with intracranial extension, but utility may vary with cyst size and complexity. This approach leverages appropriate exposure for resection with decreased morbidity and decreased incision length through avoidance of osteotomies.