Subthreshold micropulse photostimulation with true yellow 577nm diode laser for macular edema secondary to branch retinal vein occlusion

Purpose: Subthreshold, or tissue sparing, Diode Micropulse (SDM) Photostimulation is a recent retinal treatment used to produce a therapeutic effect without inducing detectable intraretinal damage. Actually SDM Photostimulation is available for diabetic macular edema (DME), central serous chorioretinopathy (CSR) and macular edema secondary to branch retinal vein occlusion (BRVO). Methods: Three patients affected by cystoid macular edema (CME) secondary to non-ischemic BRVO, diagnosed by clinical and instrumental criteria, Best Corrected Visual Acuity for distance (BCVA), Ocular Coherence Tomography (OCT) and Fluorescein Angiography (FA) were submitted to SDM Photostimulation using the IQ 577nm yellow laser system. Controls were perfomed at 3 and 6 months after the treatment. Results: Central Macular Thickness (CMT) decreased by an average of 179.76 microns, with a maximum of 89 and a minimum of 288. CME resolved completely in one case and benefited of a great reduction in the other two cases. Distance BCVA greatly improved in one case and showed a moderate gain in reading snellen lines in the other cases. Laser lesions were not clinically observed 3 and 6 months after the treatment. Conclusions: SDM Photostimulation with the IQ 577 nm yellow laser has been very effective in these three cases of CME after non-ischemic BRVO. Visual recovery, anatomic resolution of edema and absence of iatrogenic retinal damage may suggest us this treatment as an alternative to conventional more invasive therapies.