Schwannoma of the greater superficial petrosal nerve Report of 5 cases

The authors report the clinical features, imaging and surgical findings, and follow-up of 5 rare cases of schwannoma of the middle fossa with possible origin from the greater superficial petrosal nerve (GSPN). All patients presented to a single neurosurgical institution. The study design was a prospective follow-up of 5 cases of schwannomas of the middle fossa that most likely originated from the GSPN. The presenting features were burning pain in the eyes in 2 cases, epilepsy and behavioral changes in 2 cases, and headache in 1 case. Imaging studies showed a subtemporal mass on the anterosuperior aspect of the petrous bone in all cases. An enhancing tail on the MR images was highly suggestive of the origin of the tumor from the GSPN. All tumors were removed through a subtemporal extra- or intradural approach. Partial to complete peripheral facial nerve palsy was encountered after surgery in 3 cases, which recovered completely. Dry eye was the long-term permanent deficit in all cases. Mid- to long-term follow-up of the cases has not revealed any tumor recurrence. The 5 cases of schwannoma of the middle fossa with possible origin from GSPN were managed successfully, and their clinical presentation, differential diagnosis, and management are discussed. (DOI: 10.3171/2009.9.JNS09439)