The Effectiveness of Local Conservative Therapy after Panretinal Laser Coagulation against the Background of Diabetic Neuropathy

Abstract

Background: Panretinal photocoagulation (PRP) (also called scatter laser treatment) remains one of the effective methods of treatment, and it can help to prevent blindness and low vision in diabetic retinopathy (DR). The aim of this study was to investigate the efficacy of local prolonged conservative therapy after PRP and the effect of somatic polymorbidity on visual functions in patients with diabetic neuropathy (DN) at the stage of clinical manifestations based on monitoring the clinical, functional and morphometric parameters of the macular region of the retina. Methods and Results: The study included 78 patients with type 2 diabetes (T2D) who underwent PRP for DR using a VISULAS® 532s solid-state laser (ZEISS). The patients were divided into two groups depending on the presence or absence of DN. Group 1 (n=60, 120 eyes) included patients with DN (stage of clinical manifestations), Group 2 (n=18, 36 eyes) included patients without DN. All patients underwent standard ophthalmological examination: visometry, tonometry, perimetry, biomicroscopy of the anterior segment of the eye and vitreous body, and fundus ophthalmoscopy. Thickness map of the retina was obtained using the RTVue-100 OCT (Optovue, Fremont, CA) EMM5 scan protocol and the Stratus OCT (Carl Zeiss Meditec, USA) radial scan protocol. After laser treatment, all patients, regardless of the treatment stage, were prescribed topically Broxinac® ( Bromfenac ophthalmic solution 0.09%), 1 drop twice a day for a month. In the presence of macular edema, a carbonic anhydrase inhibitor (Dorzolamide 2% solution) was added to the Broxinac® solution (1 drop twice a day) for up to 1 month after each PRP stage. The dynamics of CVA parameters and the retinal thickness of the macular region were assessed before PRP and 3 months after the complex treatment. Based on the monitoring of the clinical, functional and morphometric parameters of the macular region of the retina after PRP in T2D patients, we found a local, prolonged, 3-month conservative therapy to be effective, using the instillation of Broxinac® supplemented with Dorzolamide 2% solution in the presence of macular edema. Conversely, there is a negative effect of somatic polymorbidity (stage 3 chronic kidney disease), aspartate aminotransferase >40U/L) on corrected visual acuity (CVA) and morphometric parameters of the macular region of the retina during PRP in T2D patients with DN at the stage of clinical manifestations.

Keywords

• diabetes mellitus
• diabetic neuropathy
• panretinal photocoagulation