Healing of Retinal Photocoagulation Lesions

Abstract

The decreasing width of the retinal damage zone suggests that photoreceptors migrating from unaffected areas fill in the gap in the photoreceptor layer. Laser photocoagulation parameters can be specified to avoid not only the inner retinal damage, but also permanent disorganization and scarring in the photoreceptor layer. These data may facilitate studies to determine those aspects of laser treatment necessary for beneficial clinical response and those that result in extraneous retinal damage.

Can photoreceptor loss also account for changes in pupil size following panretinal photocoagulation?

“…There are some minor studies in literature that supported our hypothesis. 2,3 The authors pointed out to a good hypothesis that the damaged peripheral retinal photoreceptors following PRP may be a partially mechanism, which explains the increased pupil size after PRP. 4 Additional studies are required to find out the exact underline mechanism.…”

“…PRP for PDR purposefully destroys a considerable fraction of peripheral rods and cones, but also directly damages the inner retina. 3 The extent of retinal damage generated by PRP is dependent upon the laser beam's diameter, power, and duration. 4 Even though the exact power of the used beams was not specified by the authors, it is conceivable that a light-intensity photocoagulation such as the one they have used, especially with conventional PRP, might have inflicted structural and functional damage not only to the photoreceptors, retinal pigment epithelium, and choroid, but also to the retinal nerve fiber layer and inner retina as well, 4,5 possibly altering the photoreceptive and integrative capabilities of ipRGCs and increasing pupil size under various conditions of illumination.…”

Human histopathology of PASCAL laser burns

“…1 PASCAL laser lesions have been well characterized in rabbits. 2 Human PASCAL burns have been analyzed with autofluorescence 3 and adaptive optics. 4 Human SD-OCT shows damage confined to the outer retina and RPE.…”

Optimal current and future treatments for diabetic macular oedema

“…There may also be preservation and/or remodelling of the outer retinal layers including filling in of initial defects in photoreceptors, presumably by sliding from adjacent areas in pre-clinical models for smaller-sized burns of 200 mm or less, that may favourably affect VEGF distribution in the retina and visual field loss. [14][15][16] …”