Comparison of micropulse subthreshold laser plus anti-VEGF versus anti-VEGF alone in diabetic macular edema: Systematic review

Intravitreal injection of anti- Vascular Endothelial Growth Factor (VEGF)is commonly used to treat patients with diabetic macular edema (DME). However, the injection alone requires high cost and compliance. Combining micropulse subthreshold laser (MPSL) and anti-VEGF is a new approach to treating DME. This study intended to answer the question of whether MPSL plus anti-VEGF is effective compared to anti-VEGF alone. The following terms were used in PubMed, clinicaltrial.gov, and Google Scholar: anti-VEGF, DME, MPSL, and diabetic retinopathy. All studies of DME comparing the intervention of MPSL plus anti-VEGF and VEGF alone between the years 2017-2021 were included. Studies with no comparison between the intervention and control group, abstract-only papers, case reports, case series, and systematic review studies were excluded. Five Randomized Controlled Trial (RCTs) and three retrospective studies were analyzed. Four studies found that best-corrected visual acuity (BCVA) improved in both therapies. Central macular thickness in six studies was also improved. The improvement differences between both therapies were insignificant and the number of anti-VEGF injections was significantly lower in combination therapy. These studies show equal outcomes of both therapies. The reduced number of anti-VEGF injections of the combination therapy could improve the management of DME in terms of cost-effectiveness. Further analysis should be conducted to pool the data from the studies and evaluate the overall outcome.