[Indications and technique for transconjunctival optic nerve sheath fenestration : Video article]

Abstract

Background: Placement of a ventricular shunt is the primary surgical procedure for lowering intracranial pressure in pseudotumor cerebri syndrome; however, if ophthalmological symptoms prevail over neurological symptoms or if there are no neurological symptoms at all, optic nerve sheath fenestration may be a valuable option for relief of pressure on the retrobulbar optic nerve when papilledema caused by pseudotumor cerebri syndrome threatens vision despite previous conservative measures.

Methods: This review covers the indications, technique and results of optic nerve sheath fenestration compared to competing procedures based on a systematic literature search, analysis of own cases and a documentation of the surgical technique.

Surgical technique: After performing a medial transconjunctival orbitotomy the medial rectus muscle tendon is temporarily detached and the eye abducted by traction sutures. Using confocal illumination under a surgical microscope, the optic nerve can be visualized using orbital spatulas and the sheath can be punctured with a microscalpel. A video of this operation is available online.

Conclusion: Transconjunctival optic nerve sheath fenestration is a relatively safe method to reduce the rate of visual loss in pseudotumor cerebri syndrome. In selected cases it can be a useful alternative to ventriculoperitoneal/atrial shunts or venous stents.

Keywords: Intracranial hypertension; Intracranial pressure; Optic nerve; Papilledema; Pseudotumor cerebri syndrome.