Optic nerve sheath decompression for visual loss in intracranial hypertension: Report from a tertiary care center in South India

Abstract

Aim:Severe visual loss is the only serious complication of intracranial hypertension secondary to idiopathic intracranial hypertension (IIH) and some cases of cerebral venous thrombosis (CVT). Optic nerve sheath decompression (ONSD) has been shown to improve or stabilize visual function in patients with IIH, while its role in CVT is yet to be established. We report our experience with optic nerve sheath decompression for visual loss in IIH and CVT.Materials and Methods:In this prospective noncomparative, interventional study, 41 eyes of 21 patients with IIH and CVT and visual loss underwent ONSD. The main outcome measures included best-corrected visual acuity (BCVA), visual fields, pupillary light reflex, optic nerve sheath diameter on B-scan and resolution of papilledema which were evaluated preoperatively and at follow-up at four days, two weeks, one month, three months and final follow-up. In 7/41 eyes with absent light perception preoperatively, the functional outcome was analyzed separately.Results:Following ONSD BCVA and visual fields stabilized or improved in 32/34 (94%) eyes. Statistically significant improvement in BCVA, visual fields and pupillary light reflex occurred over the three month follow- up period. Surgical success was indicated by reduction in optic nerve diameter and papilledema resolution occurred in all patients. The outcome in the IIH and CVT groups was comparable. Four eyes with absent light perception showed marginal improvement in visual acuity. Four eyes had transient benign complications.Conclusion:Optic nerve sheath decompression is an effective and safe procedure to improve or stabilize vision in patients with visual loss caused by IIH and CVT.

Meta-Analysis of CSF Diversion Procedures and Dural Venous Sinus Stenting in the Setting of Medically Refractory Idiopathic Intracranial Hypertension

“…We considered the number of eyes as the number of patients for calculation consistency. Nithyanandam et al 36 reported complications in terms of percentages, which we had to convert. In studies in which values of certain parameters were marginally available (eg, CSF pressure Ͼ40 cm of H 2 O in 73% of cases in the CSF diversion study by El-Saadany et al, 57 ), values were pre-sented as "NR" or not reported in On-line 3 and excluded from the mean CSF pressure.…”

Pseudotumor Cerebri: Brief Review of Clinical Syndrome and Imaging Findings

“…20,22,52 Following ONSF, visual acuity stabilized or improved in 94% of eyes and deteriorated in 6% of eyes in 2 studies. 52,53 ONSF in the pediatric population improved visual acuity in two-thirds of patients, and vision worsened in 17% of patients. 54 Some groups propose the use of venous sinus stent placement to treat IIH on the basis of several imaging studies showing stenosis of the cerebral venous sinuses and the presumption that venous outflow obstruction constitutes the underlying etiology of most cases of IIH.…”

Vision Loss 2 Weeks After Uneventful Optic Nerve Sheath Fenestration Surgery May Be Attributed to Retinal Reperfusion Injury

“…3 However, there is a considerable rate of reoperation, 10%-32%, due to failure of the initial procedure and progression of the disease. 3,6 Orbital cellulitis has also been reported. 5 However, most of the complications are trivial and not visually significant.…”

“…3,4 The procedure carries the risk of certain complications, which may be up to 45%. 6 Unfortunately, the procedure may result in permanent and severe loss of vision in less than 2% of cases. The most commonly reported complications include diplopia due to manipulation of extraocular muscles during the procedure, mainly the medial rectus, atonic pupil, and anisocoria that are believed to be due to interruption of the blood supply to the ciliary ganglion.…”