Optic Nerve Sheath Fenestration (ONSF)

Objectives. Optic nerve sheath fenestration (ONSF) is commonly used in idiopathic intracranial hypertension (IIH). Here we will present our experiences of ONSF in 26 patients with special attention to indications, surgical techniques and results Methods. The recorded data of patient management (with the result) who underwent ONSF were reviewed and studied retrospectively. Results. The total number of patients who underwent ONSF was 26. The male-female ratio was 1:12. Indications of ONSF were: 1. Idiopathic Intracranial Hypertension (IIH)-23 cases; 2. Cerebral Venous Sinus Thrombosis (CVST)-02 cases; 3. CNS Tuberculosis-01case. All patient underwent bilateral ONSF with post-operative continues lumbar CSF drain for 04 days. After fenestration gush of CSF came out with force in all-first operated eyes whereas 13-second operated eyes showed very little CSF flow after fenestration. Vision improved in different grades in all cases at discharge except in three cases. Preoperatively, visual acuity was either PL&PR or hand movement in 40 eyes where 04 eyes were preoperatively total blind (no PL&PR). Visual acuity improved in 48 eyes (92.3% eyes) where the patient can do his/her daily life activities including self-care. Improvement in IIH is 100% (23 cases i.e-46 eyes) whereas 01 case out of 02 cases in CVST. Though vision was improved dramatically fundal appearances changes very slowly and very less frequently returned to normal appearance. Conclusion. Due to the delicate and technically demanding nature of the surgery, safety is a major concern of the ONSF. Our experience showed ONSF is a technically safe operation with very good results where indicated.