The objective of this study is to assess visual outcome, tumour control and treatment-related toxicities in patients with primary ONSM in an Australian institution.

Patients with a diagnosis of primary ONSM were extracted from a prospective institutional database between January 2004 and December 2013. Patients with meningiomas of the sphenoid wing or planum sphenoidale with secondary involvement of the optic nerve were excluded. Patients were treated with radiotherapy with multiple non-coplanar dynamic conformal technique using a Novalis TX linear accelerator with ExacTrac image guidance. Treatment doses varied from a mildly hypofractionated approach of 37.5 Gy in 15 fractions to conventionally fractionated 50.4-54 Gy in 28-30 fractions, prescribed to the...

Patient and Treatment Characteristics 26 patients with ONSM treated with SRT met the criteria for inclusion in the study. All patients had unilateral diseases and were diagnosed based on characteristic radiological appearance of ONSM on MRI. The median duration of clinical follow-up was 68 months post-SRT (range 20 to 134 months). Visual Outcomes In the 10 patients with proptosis on presentation, 4 had a reduction in proptosis measured on exophthalmometry, 2 remained stable and 6 had no post-treatment data to assess response. In the three...

Patients with primary ONSM treated with SRT had excellent and durable local tumour control on MRI follow-up. Our series found that a greater proportion of patients with good vision pre-SRT had stable or improved vision indicating that early treatment should be considered in patients prior to visual deterioration.

[1]Solda F, Wharram B. Fractionated stereotactic conformal radiotherapy for optic nerve sheath meningiomas. 2012;24:106–12. [2]Shields JA, Shields CL, Scartozzi R. Survey of 1264 patients with orbital tumors and simulating lesions: The 2002 Montgomery Lecture, part 1. Ophthalmology 2004;111:997–1008. doi:10.1016/j.ophtha.2003.01.002. [3]Wright JE, McNab AA, McDonald WI. Optic nerve glioma and the management of optic nerve tumours in the young. Br J Ophthalmol 1989;73:967–74. [4]Dutton JJ. Optic nerve sheath meningiomas. Surv Ophthalmol 1992;37:167–83. [5]Carrasco JR, Penne RB. Optic nerve sheath meningiomas and advanced treatment options. Curr Opin...