Changes in Macular Retinal Layers and Peripapillary Nerve Fiber Layer Thickness after 577-nm Pattern Scanning Laser in Patients with Diabetic Retinopathy

Abstract

PurposeThe aim of this study was to evaluate the changes in thickness of each macular retinal layer, the peripapillary retinal nerve fiber layer (RNFL), and central macular thickness (CMT) after 577-nm pattern scanning laser (PASCAL) photocoagulation in patients with diabetic retinopathy.MethodsThis retrospective study included 33 eyes with diabetic retinopathy that underwent 577-nm PASCAL photocoagulation. Each retinal layer thickness, peripapillary RNFL thickness, and CMT were measured by spectral-domain optical coherence tomography before 577-nm PASCAL photocoagulation, as well as at 1, 6, and 12 months after 577-nm PASCAL photocoagulation. Computerized intraretinal segmentation of optical coherence tomography was performed to identify the thickness of each retinal layer.ResultsThe average thickness of the RNFL, ganglion cell layer, inner plexiform layer, inner nuclear layer, inner retinal layer, and CMT at each follow-up increased significantly from baseline (p < 0.001), whereas that of the retinal pigment epithelium at each follow-up decreased significantly from baseline (p < 0.001). The average thickness of the peripapillary RNFL increased significantly at one month (p < 0.001). This thickness subsequently recovered to 7.48 µm, and there were no significant changes at six or 12 months compared to baseline (p > 0.05).ConclusionsEach macular retinal layer and CMT had a tendency to increase for one year after 577-nm PASCAL photocoagulation, whereas the average thickness of retinal pigment epithelium decreased at one-year follow-up compared to the baseline. Although an increase in peripapillary RNFL thickness was observed one month after 577-nm PASCAL photocoagulation, there were no significant changes at the one-year follow-up compared to the baseline.

A meta-analysis to study the effect of pan retinal photocoagulation on retinal nerve fiber layer thickness in diabetic retinopathy patients

“…All the studies were arranged according to the year of publication in ascending order [21][22][23][24][25][26][27][28][29][30], the mean and was recorded in the form of continuous variables, and the difference in the weighted mean and standard deviation was then calculated.…”

Conventional and Pattern Scanning Pan-Retinal Photocoagulation Laser in Diabetic Patients’ Visual Field

“…In the pattern scanning method, which is also known as short duration, shortening the pulse duration of the laser reduces total energy, which consequently causes less thermal damage to the retina and less patient discomfort compared to the conventional method. [9][10][11][12] One of the side effects of PRP is peripheral vision damage. This study aimed to compare the visual field defects in two different methods of conventional PRP and pattern scanning PRP in patients with proliferative and very severe nonproliferative diabetic retinopathy.…”