Review of periorbital nerve enlargement and biopsy techniques

Periorbital nerve enlargement commonly indicates perineural invasion of malignancy or inflammatory conditions. This study reviews the role of supraorbital and infraorbital nerve biopsies in patients presenting with radiographic enlargement and to elucidate the surgical technique involved. A retrospective chart review (1997-2014) was performed at a single tertiary center. Patients with radiographic confirmation of enlarged supraorbital/infraorbital nerves that underwent biopsy were included. Charts were reviewed for: patient demographics and history, clinical symptoms and findings, radiographic findings, surgical method, and treatment. Five patients (4 female, 1 male) met inclusion criteria. Average age was 72.4 years (range 36-90). Four patients had history of cutaneous malignancy. All presented with diplopia and/or dysesthesias. Clinical examination confirmed decreased V1 and/or V2 sensation for 4 patients. Imaging revealed enlargement of V1, V2, and/or V3 in all patients. Infraorbital nerve biopsies were performed in 3 patients via transconjunctival fornix-based orbitotomy with subperiosteal dissection along orbital floor followed by unroofing of infraorbital canal. The remaining 2 underwent supraorbital nerve biopsy via sub-brow incision onto superior orbital rim with reflection of periosteum. Biopsies confirmed squamous cell carcinoma(3), mucoepidermoid carcinoma(1), and idiopathic orbital inflammation(1). Three patients initiated treatment in <1 month. One decided to follow-up closer to home, one was lost to follow-up. For patients presenting with enlarged supraorbital/infraorbital nerves, biopsy can rapidly confirm the underlying condition and facilitate early treatment. A sub-brow approach offers direct access to supraorbital nerve while transconjunctival fornix-based anterior orbitotomy with canal unroofing allows access to infraorbital nerve.