Abstract
Purpose:
To analyze the morphometric changes of distinct retinal layers measured around the optic disc by SD-OCT after pan-retinal photocoagulation
Methods:
Patients were examined monthly with Fluorescence Angiography (FA) following a specific examination protocol for diabetic retinopathy and a peri-papillary ring-scan with Spectral-Domain Optical Coherence Tomography before and after undergoing a single-session pan-retinal photocoagulation during 6 months. Thickness measurements of distinct retinal layers were then performed and analyzed.
Results:
One month after pan-retinal photocoagulation a significant increase of average peripapillary outer nuclear layer (p = 0.007) and whole retinal thickness (p = 0.006) was found. This was followed by a slow decline to baseline values over the following five months. The mean combined thickness of the retinal pigment epithelium and the photoreceptor cell layer was significantly reduced one month after laser treatment (p < 0.001). This decrease was followed by a slow increase until month 6, but did not reach original thickness values.
Conclusions:
Pan-retinal photocoagulation leads to diffuse, but reversible morphometric changes of retinal layers measurable by peripapillary OCT. The found short-term increase of retinal thickness can be mainly attributed to an increase of outer nuclear layer thickness and was accompanied by a permanent attenuation of retinal pigment epithelium and photoreceptor cell layer. The reversible changes of peripapillary retinal structure observed in-vivo could be interpreted as signs of diffuse retinal inflammation following laser treatment.
Keywords: 499 diabetic retinopathy •
578 laser •
557 inflammation