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.

Background:Sphenoid wing meningiomas extending to the orbit (ePMSW) are currently removed through several transcranial approaches. Presenting the largest surgical cohort of hyperostosing ePMSW with the longest follow up period, we will provide data supporting minilateral orbitotomy with excellent exposure for wide resection of all compartments of the tumor.Methods:A retrospective survival analysis is made of the data cumulated prospectively during a period of 34 years, including 88 cases of ePMSW with a mean follow up period of 136.4 months. The impact of preoperative variables upon different outcome measures is evaluated. Standard pterional craniotomy was performed in 12 patients (C) while the other 76 cases underwent the proposed modified lateral miniorbitotomy (LO).Results:There were 31 men and 57 women. The age range varied between 12 and 70 years. Patients presented with unilateral exophthalmos (Uex) ranging between 3 and 16 mm. Duration of proptosis before operation varied between 6 months and 16 years. The status of visual acuity (VA) prior to operation was: no light perception (NLP) in 16, light perception (LP) up to 0.2 in 3, 0.3–0.5 in 22, 0.6–0.9 in 24, and full vision in 23 patients. Postoperatively, acceptable cosmetic appearance of the eyes was seen in 38 cases and in 46 mild inequality of < 2 mm was detected. Four cases had mild enophthalmos (En). Among those who had the worst VA, two improved and one became almost blind after operation. The cases with VA in the range of 0.3–0.5 improved. Among those with good VA (0.5 to full vision), 2 became blind, vision diminished in 10, and improved or remained full in the other 35 cases. Tumor recurrence occurred in 33.3% of group C and 10.5% of group LO (P = 0.05). The major determinant of tumor regrowth was the technique of LO (P = 0.008).Conclusion:Using LO technique, the risky corners involved by the tumor is visualized from the latero-inferior side rather than from the latero-superior avenue. This is the crucial milestone to achieve aggressive removal of all the involved compartments of the lesion. Satisfactory cosmetic result is reported using mini LO technique after widely exposing and removing the hyperostotic bone down to the subtemporal fossa with only simple repair of the dura without cranioplasty.