It has been used in treatment of progressive non-arteritic ischemic optic neuropathy, and optic disc drusen.12 It has also been used in case of cryptococcal meningitis secondary to acquired immunodeficiency syndrome successfully.13 We used ONSF effectively for treating papilledema secondary to dural sinus thrombosis and intracranial masses, besides IIH, causing sufficient raised ICP to cause visual deterioration.
Resolution of papilledema is therefore expected to improve vision in patients undergoing ONSF. Studies analysing the histological features of IIH have shown that vision loss from outer retinal layer changes in the macula is typically reversible, while vision loss from optic neuropathy and inner retinal layer change is less reversible.15 We also didn't find any significant correlation between mean change in BCVA and stage of papilledema or pre-operative BCVA.
Fig.1 shows pre-operative and post-operative fundus photographs of a patient who underwent bilateral ONSF. Fig.2 shows common complications observed after the procedure.
Previously, studies on ONSF were mainly focused on treatment of IIH only.
ONSF, originally described by DeWecker in 1872, is a promising interventional treatment modality which has proved effective in prevention of visual and VF loss.8 Hayreh, besides contributing towards description of blood supply of optic nerve, also described the efficacy of ONSF in resolving papilledema.9 The literature shows varied efficacy of ONSF procedure.
All patients were counselled regarding ONSF surgery and its possible complications.
Medical treatment includes Acetazolamide, Steroids, Topiramate, Frousemide and surgical treatment options include Optic Nerve Sheath Fenestration (ONSF) or CSF shunt (lumboperitoneal shunts, ventriculo-peritoneal shunts, or ventriculoatrial shunt).3,6,7
Conclusion: ONSF is an effective procedure with statistically significant improvement in BCVA and reduction in severity of papilledema.
Objective: To evaluate the efficacy and safety of Optic Nerve Sheath Fenestration (ONSF) in patients with raised intracranial pressure (ICP).
Methods: This Quasi Experimental Study was conducted at Armed Forces Institute of Ophthalmology, Rawalpindi from July 2013 to July 2015.Thirty one eyes of 18 patients who underwent ONSF for raised ICP were followed up for one year to ascertain efficacy and safety of ONSF procedure.