Abstract
Purpose:
Radial optic neurotomy (RON) is a surgical treatment originally described for central retinal vein occlusion (CRVO). Surgical treatment with RON was thought to relieve high pressure on the central retinal artery, central retinal vein, and optic nerve fibers by dissecting the scleral ring. Optic disc drusen can cause compression of the neurovascular bundle within the optic nerve. There is no treatment available for optic disc drusen except case reports and case series proposing the use of RON. Previous reports on the short term outcome of RON in optic disc drusen demonstrated efficacy and safety. This case series presents six year outcomes of three patients that challenges the efficacy and safety of RON in patients with optic disc drusen.
Methods:
Radial optic neurotomy was performed on one of two eyes in three patients with bilateral optic disc drusen with progressive visual field defect. The eye with the worse visual field defect was selected for the operation. Par plana vitrectomy was performed followed by RON. RON was performed using a microvitreoretinal blade was used to make an incision into the scleral ring, cribriform plate, and adjacent sclera of the optic disc. Disease progression was monitored in both eyes with ETDRS visual acuity, Humphrey visual field 30-2, and optical coherence tomography.
Results:
Surgery was performed without complications in all three patients. At six years, none of the three patients had improvements in their visual acuity or visual field when compared to baseline. Two of three patients developed visually significant cataract in the treated eye requiring cataract surgery and the third patient developed an epiretinal membrane. Of the three patients, one developed a temporal visual field defect associated with the radial optic neurotomy incision.
Conclusions:
This case series shows six year follow up data that challenges previously reported efficacy and safety of RON in patients with bilateral optic disc drusen. Our study did not show an improvement in visual acuity or visual field in the treated eye. This surgical treatment led to decrease in visual acuity in two of three patients and loss of visual field in one of three patients.
Keywords: 504 drusen •
627 optic disc •
688 retina