https://doi.org/10.31288/oftalmolzh201463439

Ultrastructural changes of the retinal neuroepithlium of rabbits after subthreshold laser influence by laser generating radiation with the wavelength of 532 nm, 577 nm and 810 nm with application of milliimpulse and microimpulse operating conditions of the laser

Romanova T. A.

State Institution The Filatov Institute of Eye Diseases and Tissue Therapy of the NAMS of Ukraine; Odessa, (Ukraine)

Key words: ultrastructural changes of rabbit retinal neuroepithelium, sub­threshold laser action.

Introduction. This article studied the ultrastructural changes of rabbit retinal neu-roepithelial after subthreshold exposure lasers of different wavelengths. At the pres­ent stage of development of ophthalmology retinal laser photocoagulation remains the «gold» standard of care for retinal vascular disease. However, this method has a number of complications, so is especially urgent search for alternative methods of application of laser energy, which would not have undesirable side effects. Purpose. The aim was to study the effect of subthreshold laser effects on rabbit retinal neuroepithelial lasers generating radiation with a wavelength of 532 nm, 577nm and 810 nm using millipulse and micropulse laser modes by electron mi­croscopy.

Methods. Work performed on the 3rd adult rabbits (5 eyes) Chinchilla, age 6—7 months, weighing 2.5—3kg. Laser scars apply in the lower segments of the eyes, which were divided arbitrarily into two parts to perform the confluent and not confluent laser photocoagulation, using laser radiation of different wavelengths. Laser effect on the rabbit retina was carried out in two modes of operation of the laser: in millipulse and micropulse, used only subthreshold power laser exposure. Results. Electron microscopy examination showed that the not confluent laser pho­tocoagulation has less damaging effect on the rabbit retinal neuroepithelial than the confluent laser photocoagulation. The confluent laser burns 577 nm optical radiation in millipulse laser mode on the rabbit retina are observed less damage than when a similar influence of the laser wavelength of532 nm. However, if you do not confluent laser burns the method of application of burns when exposed to a laser wavelength of 577 nm in millipulse mode of the neuroepithelial is far less damaging changes. There is preservation of the outer and inner segments of pho-toreceptor cells. Electron microscopy examination showed that after exposure to the laser wavelength of 810 nm micropulse mode laser, with no confluent method of application of burns on the retina of the rabbit observed the least damage to the neuroepithelial than in similar influence of the laser wavelength of 532 nm and 577 nm.

Conclusion. Found that the least damaging effect on the rabbit neuroepithelial has radiation with a wavelength of 810 nm. Changes in Muller cells were observed after almost all laser effects on rabbit retina.

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