Intra-retinal Arterial Cannulation using a Microneedle for Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is a severe disease, often causing blindness. We evaluated the efficacy and safety of a surgical procedure for the treatment of acute CRAO in which retinal arterial cannulation with tissue plasminogen activator (tPA) is performed. The surgical procedure consisted of vitrectomy followed by cannulation of the central retinal artery and injection of tPA (200 μg) using a 47-gauge microneedle. Thirteen CRAO patients were treated within 48 hours of the onset of symptoms. The central retinal artery of all 13 eyes was successfully cannulated. The mean interval between the onset of symptoms and surgery was 38.7 hours. The results for all 13 eyes treated showed a statistically significant improvement in mean visual acuity between before and one month after treatment (-1.60 vs. -0.82 logarithmic values for minimum angle resolution (LogMAR), p = 0.0021). Fluorescein angiography showed complete reperfusion and incomplete reperfusion in 10 eyes and 3 eyes, respectively. Recently developed surgical instruments have made retinal-arterial cannulation feasible. Intra-retinal-arterial cannulation has potential as a method of improving visual function and microcirculation in eyes affected by CRAO.