EVALUATION OF THE NAVIGATION AND PATTERN-TECHNOLOGIES EFFICACY IN THE TREATMENT OF PROLIFERATIVE DIABETIC RETINOPATHY

Purpose: to evaluate the structural changes of the retina after panretinal laser coagulation of the retina in single coagulate mode, pattern and navigation technologies with lasers of different wavelengths and exposures.

Materials and methods of research. A prospective study included two main stages, 78 patients with type 2 diabetes mellitus, with the proliferative stage of diabetic retinopathy, who underwent panretinal laser coagulation (PRC). 4 groups of patients were formed. At the first stage, the quality of coagulate formation, structural changes in the surrounding retina and changes in light sensitivity before and after laser coagulation were evaluated. At the second stage, the efficacy of retinal laser coagulation was studied depending on the laser coagulation technology.

Optical coherence tomography RTVue XR Avanti (Optovue, USA), Canon was included in the diagnostic examination. The structural changes of the retina were evaluated before and after laser exposure. A study of the light sensitivity of the central parts of the retina was conducted using the Octopus 900 HAAG-STREIT perimeter (Switzerland). The severity of the pain syndrome at the time of the operation was assessed using a visual analog scale 30 minutes after the operation

Results. The formation of a full-fledged chorioretinal scar was observed with all types of laser exposure. It has been proven that a laser with a wavelength of 577 nm with an exposure of 20 ms has a minimal damaging effect, as evidenced by the absence of damage to the outer boundary membrane, outer segments of photoreceptors according to OCT data, as well as the absence of depression of average light sensitivity. According to the results of the pain perception study, it was found that patients who underwent coagulation on the Navilas 577s laser system in automatic mode (exposure of 20 msec) practically did not experience pain.

Conclusions. An assessment of the structural changes in the retina revealed the least damaging effect on the retinal tissue of laser coagulation with a wavelength of 577 nm with an exposure of 20 msec using pattern and navigation technologies, which allowed the photosensitivity of the peripheral parts of the retina to be maintained at the initial level. When using pattern and navigation technologies, the side effects of surgery (pain, glare,) are not pronounced, which makes panretinal laser coagulation comfortable and increases the patient's commitment to this type of treatment.

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