Argon laser vs. subthreshold infrared (810-nm) diode laser macular grid photocoagulation in nonexudative XXXX .

@entity1 @entity1020 @entity66 @entity941
BACKGROUND: A diode laser can be used to create a subthreshold (invisible end point) lesion in @entity1 with @entity1020 ( @entity1020 ). This has the potential benefit of localizing the treatment effect to the retinal pigment epithelium and sparing more of the overlying sensory retina. We performed a study to compare the safety and efficacy of argon laser and subthreshold infrared (810-nm) diode laser macular grid photocoagulation in reducing the number of drusen in @entity1 with @entity1020 . METHODS: We reviewed the charts of 144 @entity1 with bilateral early-stage nonexudative @entity1020 , characterized by soft drusen. One eye of each @entity1 was treated, and the other eye served as a control. Seventy-eight eyes of 78 @entity1 with a mean age of 67.5 (standard deviation [SD] 8.3) years underwent argon laser macular grid photocoagulation at a university-affiliated hospital in Bologna, Italy, and 66 eyes of 66 @entity1 with a mean age of 66.4 (SD 6.3) years underwent subthreshold infrared (810-nm) diode laser macular grid photocoagulation at a private clinic in Bologna. Each group was classified into three subgroups based on the number of drusen (more than 20, 10 to 20, or less than 10). The @entity1 underwent @entity941 angiography, fundus examination, measurement of far (Snellen chart) and near (Jaeger chart) best corrected visual acuity, and visual field and contrast sensitivity testing. The mean length of follow-up was 18 (SD 0.5) months. RESULTS: At 18 months, far and near best corrected visual acuity were statistically significantly improved in the treatment groups compared with the untreated group (p < 0.001, Mann-Whitney U test). There was no significant difference in visual acuity between the treatment groups. Compared with baseline, the number of drusen was significantly reduced in both treatment groups (p < 0.001). @entity66 was observed in the untreated group. The visual field was slightly but significantly reduced after argon laser treatment (p < 0.001) but not diode laser treatment; the difference in visual field between the two groups was not significant. There was a slight reduction in contrast sensitivity, particularly with night vision, after argon laser treatment but not diode laser treatment. The difference between the two treatment groups was significant (p < 0.01). INTERPRETATION: Subthreshold infrared diode macular grid photocoagulation may be a safe and viable method for preventing progression of nonexudative @entity1020 .
