Purpose
To evaluate the visual outcomes of optic nerve sheath fenestration (ONSF) and shunting procedures in patients with idiopathic intracranial hypertension (IIH).
Methods
Retrospective observational case series in which the medical records of patients with severe idiopathic intracranial hypertension who underwent surgical treatment at the Johns Hopkins Hospital were reviewed for demographics and clinical findings. Patients who underwent ONSF were compared to shunted patients.
Results
Thirty-eight patients (35 women and 3 men) with a mean age of 30.3 years (range, 9-52) underwent surgical treatment of IIH (16 ONSF, 22 shunt). Pre-operative Frisen scale papilledema in the ONSF group was grade 3 (14.3%), grade 4 (71.4%) and grade 5 (14.3%). In the shunt group 27.8% of patients had pre-operative optic atrophy, grade 1 (16.7%), grade 2 (33.3%), grade 3 (16.7%) and grade 4 (5.5%). Pre-operative visual acuity (VA) was 60.6 ETDRS letters in the ONSF group and 73.9 letters in the shunt group (p=0.13). There was a trend towards worse pre-operative mean deviation in the ONSF group (-22.94 dB vs -14.86 db, p=0.09). At the last follow-up mean VA was 75.3 letters in the ONSF group and 77.0 letters in the shunt group (p=0.56). Mean deviation was worse after ONSF (-17.36 dB vs -8.78 dB, p<0.05).
Conclusions
Both ONSF and shunting are effective procedures in stabilizing or improving visual acuity and visual fields in IIH patients. In general there was a trend towards worse visual pre-operative visual function that could explain the worse visual fields outcomes after ONSF.
Keywords: 627 optic disc •
759 visual impairment: neuro-ophthalmological disease