The role of retinal focal photosensitivity in micropulse treatment of vascular genesis focal macular edema

Introduction. Vascular macular edema (ME) is the most common in diabetic retinopathy and retinal vein occlusion. To assess the efficacy and safety of ongoing treatment the dynamics of the best-corrected visual acuity is always taken into account, however, taking into consideration the subjectivity of this indicator, objective methods of assessing the morphofunctional state of the retina should be performed. These include optical coherence tomography and microperimetry.

The aim of the study is to evaluate the role of focal retinal photosensitivity (FRP) in assessing the efficacy of micropulse treatment of macular edema of vascular genesis.

Material and methods. The study group consisted of 110 patients (110 eyes) including 74 patients (74 eyes) with diabetic macular edema (DME) up to 500 μm and 36 patients (36  eyes) with ME up to 500  μm caused by branch retinal vein occlusion. The patients were divided into two groups randomly: in the first group micropulse was performed using a green laser (λ = 532 nm), in the second group – a yellow laser (λ = 577 nm).

Results. In both groups ME decreased significantly to 342 ± 11 µm (M ± σ), maximum corrected visual acuity and FRP increased to 0.59 ± 0.07 and 23.9 ± 1.7 dB (M ± σ), accordingly. Statistically significant difference in treatment efficacy depending on laser length wasn’t detected.

Conclusion. FRP in the area of edema of neuroepithelium (NE) has a direct correlation with NE thickness and is an important indicator of the retinal functional state and can be used to develop a personalized approach to patient treatment and assess the effectiveness of ME treatment. Application of micropulse for treatment of vascular genesis focal ME with height up to 500 μm is effective and safe, as it allows to decrease reliably the thickness of NE in the edema zone and improve clinical and functional indices, reliably increase FRP.

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