Optic nerve sheath fenestration for treating papilloedema in the era of cerebral venous sinus stenting.

We review our experience with optic nerve sheath fenestration (ONSF) in 35 patients with Pseudotumor Cerebri syndrome (PTC) over the period 2002 to 2021, in the new era of endovascular transverse venous sinus stenting (TSS) for this condition. Of the 35 patients, 30 had primary PTC (i.e. idiopathic intracranial hypertension - IIH), 5 had secondary PTC, in 3 cases due to malignant meningitis and 2 due to venous sinus thrombosis. All 35 patients had high lumbar CSF pressures ranging from 250 to 470 mm H 2 O. All patients had brain magnetic resonance imaging which had at least some changes attributable to PTC. Eighteen patients had bilateral ONSF and 17 patients unilateral ONSF, in each case of the worse eye. Of the 35 patients, 20 had catheter venography with manometry (5 before and 15 after ONSF). Venography showed stenoses of both transverse sinuses in 9 patients and of the dominant transverse sinus in 11. Thirteen patients then underwent transverse sinus stenting (TSS), in each case following ONSF. The primary outcome measures were visual acuity (VA) and mean deviation (MD) on visual field (VF) testing. MD improved by 5dB or more in 34 of 70 total eyes (48.6%); VA improved by 0.2 logMAR (two lines on Snellen chart) or more in 21 eyes (30%), and by both in 15 eyes (21.4%). MD deteriorated by 5dB or more in 6 eyes (8.6%); VA deteriorated by 0.2 (two lines) or more (mean 0.7) in 9 eyes (12.9%), and by both in 5 eyes (7.1%). Final MD was -10dB or better in 38 eyes (54.3%); final VA was 0.3 (6/12) or better in 54 eyes (77.1%), and both in 39 eyes (55.7%). Final MD was -20dB or worse in 19 eyes (27.1%) (7 of these 19 started off at least 5dB better); final VA was 1.0 (6/60) or worse (1.6) in 10 eyes (14.3%) (4 of these 10 started off at least one line better). Our results confirm that even unilateral ONSF can relieve papilloedoema in both eyes and improve both VF and VA, even in cases of fulminant PTC with severe acute visual impairment. This article is protected by copyright. All rights reserved.