To compare the therapeutic effects and complications after panretinal photocoagulation (PRP) and discomforts of patients using patterned PRP versus conventional PRP for diabetic retinopathy.

Eighty patients who required PRP due to diabetic retinopathy were enrolled in a prospective randomized controlled study. The patients were randomly divided into two groups: a patterned PRP group in which PRP was performed with a short laser exposure time (0.02 seconds) and a conventional PRP group with a long exposure time (0.2 seconds). At the 1-year follow-up visit, the progressions of diabetic retinopathy, best-corrected visual acuity, and central macular thickness were evaluated. All patients were questioned about the grade of pain during PRP. In addition, the complications after PRP were investigated.

There were no statistical differences in clinical characteristics between both groups. The progression of diabetic retinopathy was not different in both groups at the 1-year follow-up visit. The best-corrected visual acuities at 1, 2, 4, and 8 weeks after PRP were decreased in both groups and, in the conventional PRP group, the decrements of visual acuity were greater than in the patterned PRP group. The increments of central macular thickness were also greater in the conventional PRP group than the patterned PRP group.

When patterned PRP is performed using a short laser exposure time, the efficacy in the treatment of diabetic retinopathy is similar to that of the conventional PRP using a longer laser exposure time. Moreover, patterned PRP is less painful, and fewer complications.