Related Experiment Video
Updated: Jun 10, 2026
Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management
Published on: March 28, 2025
Pain perception at laser treatment of peripheral retinal degenerations with green and infrared wavelengths
Rodrigo Pessoa Cavalcanti Lira1, Mauricio Abujamra Nascimento, Carlos Eduardo Leite Arieta
1State University of Campinas-Unicamp, Recife, Brazil. rodrigopclira@hotmail.com
Purpose:
To compare the pain perception at laser treatment of peripheral retinal degenerations with green (532-nm) and infrared (810-nm) wavelengths.
Design:
Prospective randomized clinical trial.
Methods:
Sequential patients with indications for photocoagulation of bilateral peripheral retinal degenerations were invited to participate in the study. Thirty patients (60 eyes) were enrolled in the study. Each patient had 1 eye treated with infrared laser (diode, 810-nm wavelength) and the other eye treated with green laser (frequency-doubled solid-state laser, diode-pumped, with 532-nm wavelength). The eyes were randomized to infrared or green wavelengths. The right eye was the first treated in all cases regardless of the wavelength arrangement. Immediately after photocoagulation of each eye, the patient was asked to grade pain perception according to an 11-point (ie, 0-10) numerical rating scale (NRS), with 0 meaning "No pain" and 10 meaning "Pain as bad as you can imagine." The primary outcome was the assessment of pain.
Results:
The mean grading of pain perception was 2.80 (SD 1.27; mode and median = 2) to green wavelengths and 5.07 (SD 1.36; mode = 4 and median = 5) to infrared wavelengths (P < .001).
Conclusions:
The results showed a statistically and clinically significant difference of pain perception between the 2 groups, with advantage to the green laser group.
