Orbital Apex Tumors Treated With Gammaknife Radiosurgery

1. Alice Siew Ching Goh 1,2
2. Byung Chun Park 2
3. Kyung In Woo 2
4. Jung-il Lee 3
5. Yoon-Duck Kim 2

1. 1 Department of Ophthalmology, Hospital Serdang, Kuala Lumpur, Malaysia
2. 2 Department of Ophthalmology , Samsung Medical Center, Sungkyunkwan School of Medicine, Seoul, Korea
3. 3 Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan School of Medicine, Seoul, Korea

Objective: The orbital apex is an important anatomical landmark that hosts numerous neurovascular structures. Tumor resection located at this complex region poses therapeutic challenge to oculoplastic surgeons and is often associated with unavoidable serious complications. We report the efficacy and safety of gamma knife radiosurgery (GKS) in 4 patients with tumors located at the orbital apex.

Design: Retrospective, non comparative, interventional case series.

Method: Medical records of patients diagnosed with orbital apex tumors and underwent gamma knife radiosurgery from 2004 to 2009 were analyzed. Changes in visual acuity, visual field and tumor volume were recorded. The median follow up period was 13.5 months (range, 6 to 18 months)

Results: Four patients were identified, three males and one female. The age ranged from 26 to 34 years with the median age of 30. The tumors consisted of three cavernous hemangiomas and one schwannoma. A total radiation dose of 20 Gy in 4 fractions were delivered to all patients. All four patients had impaired visual acuity on presentation. The median visual acuity before treatment was 1.5 on LogMar chart and improved to 0.8 after treatment. Visual field improved in three patients and tumor size decreased in all patients. No adverse events were noted during and after the surgery.

Conclusion: From our experience, gamma knife radiosurgery appears to be an effective and safe management strategy to treat orbital apex tumors.