The effect of short versus long exposure times of argon laser panretinal photocoagulation on proliferative diabetic retinopathy.

We performed a randomized clinical trial comparing short-duration (0.1 s) with long-duration (0.5 s) blue-green argon laser burns to deliver panretinal photocoagulation (PRP) in eyes suffering from proliferative diabetic retinopathy with high risk characteristics. We studied 19 eyes in the 0.1-s group and 24 eyes in the 0.5-s group for 6 months. Two or more lines of acuity were lost by 20% of the 0.1-s PRP eyes, but by only 8% of the 0.5-s PRP eyes; New or increased vitreous hemorrhages occurred in 30% of the 0.1-s PRP eyes, but in only 16% of the 0.5-s PRP eyes; New or increased traction retinal detachments did not occur in the 0.1-s PRP eyes, but occurred in 16% of the 0.5-s PRP eyes. There was complete disc neovascular regression in 85% of the 0.1-s PRP eyes and 81% of the 0.5-s PRP eyes. These trends were not statistically significant.