Background and objective: To compare pain intensity with single-spot versus multispot technique in laser panretinal photocoagulation, using a 532-nm, solid-state laser system.
Materials and methods: This was a prospective, interventional, randomized, single-masked comparison trial. Patients received two types of intervention: conventional single-spot technique, with an exposure time of 150 ms, and multispot technique, done with an exposure time of 20 ms, Both techniques used power sufficient to produce visible gray-white burns, and spot size of 20 μm. Participants received both treatments in the same eye, each one in one hemiretina, and were randomized to receive first single- or multispot technique and to the initial site of treatment. We assessed pain intensity using a numerical pain scale immediately after completion of each treatment.
Results: A significantly lower pain scale was observed with the multispot when compared with the single-spot technique (coefficient [Coef]: -1.61; 95% CI, -2.49 to -0.74; P < .001), which was not affected by treatment order, the hemiretina treated, or treatment duration (P > .05). Among demographic characteristics, multiracial patients had a pain scale 1.25 greater than that of White patients (Coef: 1.25; 95% CI, 0.47 to 2.04; P = .002), but there is no effect of age or sex on the pain scale (P > .05). Regarding treatment duration, a shorter procedure was also observed in the multispot technique (Coef: -1.13; 95% CI, -1.43 to -0.82; P < .001), and it was not affected by order of treatment (P = .098), hemiretina (P = .327), pain (P = .141), or demographic data, such as age, sex, and race (P > .05).
Conclusion: The use of the multispot technique, with a short pulse duration (20 ms), is significantly less painful and less time-consuming for patients with proliferative retinopathy compared with the conventional single-spot technique using an exposure time of 150 ms. [Ophthalmic Surg Lasers Imaging Retina. 2022;53:40-45.].