Role of laser peripheral iridotomy in pigmentary glaucoma and pigment dispersion syndrome: A review of the literature

Summary Purpose Pigment dispersion syndrome (PDS) is characterized by a structural abnormality of the posterior surface of the iris causing contact with the zonular fibers. It can lead to an open-angle glaucoma secondary to pigment dispersion into the trabecular meshwork. Laser peripheral iridotomy (PI) has been proposed as a treatment for pigmentary glaucoma (PG) and pigment dispersion syndrome (PDS) by reducing the dispersion of pigment. The goal of this review was to assess the effects of PI for PDS and PG. Methods We included six randomized controlled trials and two cohort studies (286 eyes of 218 participants). Four trials included participants with PG, and 4 trials enrolled participants with PDS with or without elevated intraocular pressure (IOP). Results Among patients with PG, at an average of 9 months of follow-up, the mean difference in IOP between groups was 2.69 mm Hg less in the PI group (95% CI: −6.05 to 0.67; 14 eyes). In patients with PDS, the average IOP was statistically lower after PI as compared to baseline (Student test t  = 11.49, P Conclusion PI decreases the biomechanical factor causing contact between the iris and zonular fibers and may lower IOP over the long-term. Nevertheless, the effects of PI on visual field changes or progression have not been established in PG and PDS. There is no scientific evidence as of yet to advocate PI as a treatment for PDS or PG.