[Long-term outcome of optic nerve sheath fenestration in pseudotumor cerebri]

Abstract

Background: Chronic papilledema may lead to irreversible damage of optic nerve fibers. To preserve visual functions, a decompression of the optic nerve is recommended by means of a fenestration of the optic nerve sheath. In this study long-term results after optic nerve sheath fenestration in patients with idiopathic pseudotumor cerebri are reported.

Patients and methods: 14 patients were re-examined 15 to 145 months (mean 62 months) after a fenestration of the retrobulbar optic nerve sheath on 23 eyes by a transconjunctival approach. Surgery was done to treat progressive visual loss or in severe obscurations. The patient's symptoms, visual acuity, visual fields, and ophthalmoscopic findings of the optic nerve head and the central fundus were compared to the preoperative status.

Results: Re-examination revealed improvement or stabilisation of objective and subjective findings in 17 eyes, one of them was operated on the more involved contralateral side only. Six eyes showed a recurrence of the papilledema without a functional change for the worse after an interval of 7 to 121 months. Three eyes of two patients ended up with optic atrophy and extensive visual loss. Preoperatively, these eyes had shown cotton wool spots in the optic nerve head and a rapid deterioration of vision.

Conclusions: Fenestration of the retrobulbar optic nerve sheath can prevent further visual loss in most patients with pseudotumor cerebri, unless the eye has already become nearly blind. Postoperatively, ophthalmological controls are necessary at regular intervals because relapses after successful surgery can occur after months or years.