Algorithm for the treatment of advanced proliferative diabetic retinopathy

Abstract

Purpose. To develop an algorithm for the treatment of patients with advanced proliferative diabetic retinopathy with the determination of the stages of laser and surgical methods and evaluate its effectiveness. Material and methods. The study group included 38 patients (38 eyes) with type 1 diabetes mellitus (21 patients) and type 2 diabetes mellitus (17 patients, 16 of them with the insulin-requiring form of the disease). Patients age ranged from 24 to 75 years (41±8.6 years) old. All patients underwent staged treatment. Primary subtotal three-port 27 G vitrectomy was performed. Transpupillary patterned panretinal laser coagulation was performed at 1,5–2 months after the first stage of treatment. Panretinal laser coagulation was performed with a hexagonal matrix pattern with a laser spot diameter of 300 µm, exposure time of 30 ms on an Integre Pro Scan laser device (Ellex, Australia) with a wavelength of 561 nm using a panfundus lens. In cases of gas-air tamponade, panretinal laser coagulation was performed according to the same parameters in two sessions with an interval of 1–2 months between them, the average number of coagulates per session was 1053±107 applications. As the third stage of treatment, 1,5–2 months after panretinal laser coagulation, those patients whose vitreal cavity was tamponed with silicone oil underwent vitrectomy with the removal of silicone oil and it's replacement with a balanced solution. Results. The total number of treatment steps in the observation group (n=34) ranged from 1 to 5 and averaged 3±0.97. The time from primary vitrectomy followed by patterned panretinal laser coagulation to silicone oil removal was at average 3.7±0.48 months. Performing primary subtotal vitrectomy as the first stage of combined treatment made it possible achieve retinal attachment and its visualization throughout, to perform surgical intervention without massive endolaser coagulation, which reduced the duration of surgery and accelerated postoperative rehabilitation. The subsequent transpupillary panretinal laser coagulation of the retina in the pattern mode provided a dosed precision effect on the retina and made it possible perform the laser stage of treatment in one session. Conclusion. A step-by-step algorithm, including primary subtotal vitrectomy followed by simultaneous transpupillary pattern laser coagulation of the retina, is effective and safe in the treatment of proliferative diabetic retinopathy complicated by hemophthalmos. Key words: proliferative diabetic retinopathy, treatment algorithm, surgical treatment, laser treatment, vitrectomy, pattern laser coagulation