Abstract
Purpose: :
To determine the safety of optic nerve sheath fenestration (ONSF) in the immediate 6 month postoperative period with regard to visual acuity and mean deviation of Humphrey visual field.
Methods: :
A retrospective chart review was performed evaluating 141 eyes in 69 patients with idiopathic intracranial hypertension (IIH) and 2 with secondary intracranial hypertension who underwent optic nerve sheath fenestration (ONSF) between June 2005 and June 2010.
Results: :
One hundred forty one eyes of 71 patients (69 IIH, 2 IH due to dural sinus thrombosis) were included in the study. Patients were 91.5% female and 76.1% Caucasian. The average patient age was 28.4 years (SD +/- 8.2 years) and mean opening pressure was 40.5 cmH2O (SD +/- 9.0 cmH2O). Within the six month study period, 70 eyes (49.6%) had resolution of optic disc edema clinically at a mean of 6.9 weeks (SD +/- 5.8 weeks). Twenty nine patients (40.9%) went on to eventually require neurosurgical shunting surgery with nine of those patients undergoing preplanned concurrent shunting surgery within one week of ONSF. Comparison of pre- and post-operative visual acuity had a mean of the paired differences of 0.01 logMAR (p=0.74). Comparison of pre- and post-operative visual field mean deviation had a mean of the paired differences at 1 week, 1 month, and 6 months of -2.06 dB (P<0.01), -2.45 dB (P<0.01), and -0.90 dB (P=0.12) respectively.
Conclusions: :
ONSF does not cause vision loss in the 6 month post-operative period and may represent a safe therapy for patients with intracranial hypertension refractory to medical therapy.
Keywords: neuro-ophthalmology: optic nerve • optic nerve