Radial Optic Neurotomy in Central Vein Occlussion: Clinical Results of 107 Cases

Abstract

Abstract: : Purpose: To evaluate the potential role of radial optic neurotomy (RON) a recently proposed new surgical technique on the treatment of central retinal vein occlusion (CRVO). The theory for this surgical approach is that CRVO constitutes a neurovascular compartment syndrome at the site of the lamina cribrosa which can be alleviated by performing a radial incision at the nasal part of the optic nerve relaxing the cribriform plate and the adjacent sclera. Methods: 107 patients with central retinal vein occlusion were treated by RON in 5 retinal centers. All data were analyized by one center using a standardized protocol evaluating preoperative and postoperative visual acuity (VA), fundus appearance and angiographic findings. Intra– and postoperative complications were reviewed as well. For evaluation of the fundus and angiography reference images were used. Results: On 55 right and 52 left eyes of 107 patients (55.6% male, 44.4% female) with a median age of 68 years (range 21–91 years) RON was performed. Median follow–up time was 6 months (range 1 – 24 months). Median preoperative VA was 20/400 (logMAR 1.3) increasing to a median postoperative VA of 20/250 8 (logMAR 1.1). In patients with an interval of more than 90 days between onset of CRVO and RON no significant change of VA was noted at the six months follow–up. Cases with preoperative severe peripapillary swelling of the optic nerve showed an average increase of 4.2 lines in VA at the six months follow–up. Angiographic finding of shunt vessels at the neurotomy site could be demonstrated in 18/30 cases after 12 months and was accompanied with an average improvement of VA of six lines. Visual field tests showed various defects in 86.8% of all cases. In one patient an iatrogenic injury of the central retinal artery occurred (0.9%). Conclusions: Despite the potential risk of visual field defects radial optic neurotomy seems to be a quite safe procedure. Several patients showed a rapid normalization of the fundus morphology with an improvement of visual acuity uncommon for the natural history of CRVO. However RON seems to be beneficial only in patients with a duration less than 3 months and very severe signs of peripapillary swelling.

Keywords: retina • optic disc • vascular occlusion/vascular occlusive disease