Purpose: To evaluate the clinical features, management, and outcomes of orbital schwannomas.
Methods: Retrospective study analyzing 20 orbital schwannomas in 18 patients managed in an orbital service over 26 years. Clinical, radiological, histological, and surgical procedural data were analyzed.
Results: Mean age of the study population was 40.89 ± 20.84 years. The most common nerve of origin was frontal nerve (50%), and majority of patients (70%) had a superior and/or posteriorly located tumor. Five patients (27.8%) had optic neuropathy at presentation, and 3 of them showed improved vision after intervention. Surgical resection was performed for all except for 1 patient who underwent fractionated stereotactic radiotherapy. Six subjects had extension of tumor into the cavernous sinus, and 3 of them underwent combined neurosurgical intervention with stereotactic neuronavigation. Outcomes were largely favorable with majority achieving complete excision. Two out of 6 incomplete resections experienced regrowth requiring second surgical intervention. Surgical complications include decreased vision, diplopia, ptosis, and mydriasis.
Conclusion: Orbital schwannomas are uncommon slow-growing tumors which can result in visual loss. Prognosis can be favorable even in presence of pre-operative optic neuropathy if there is early intervention. Schwannomas confined to the orbit can usually be completely excised with good outcomes. Schwannomas extending intra-cranially may undergo incomplete excision to preserve vital structures, leaving residual disease, but generally have satisfactory results. Stereotactic neuronavigation and frozen section are useful intra-operative tool to aid management and minimize complications. Fractionated radiotherapy can be considered as an alternative or adjunctive treatment for patients not amenable for surgical resections.