PRESERFLO^TM Microshunt Implantation and Multiple Non-penetrating Deep Sclerectomy in Primary Open-angle Glaucoma Surgery

Purpose: сomparative analysis of the effectiveness of PRESERFLO™ microshunt implantation and multiple NPDS in patients with refractory glaucoma.

Patients and methods. A total of 64 patients (67 eyes), including 27 male and 37 female with primary open-angle glaucoma (POAG), were examined and operated on as part of an open prospective study. All patients underwent implantation of the Preserflo™ drainage system or non-penetrating deep sclerectomy after previously performed surgical interventions for POAG (NPDS and/or implantation of various drainage models). The patients were divided into 2 groups — the Preserflo group (group I, 28 patients) and the NPDS group (group II, 36 patients). The follow-up period was 1.0 ± 0.1 years.

Results. In the study groups, complications such as hyphema (n = 2 in group I and n = 3 in group II) and ciliochoroidal detachment (n = 1 in group I and n = 2 in group II) were identified in the early postoperative period. In group I, severe hypotension was noted on day 1 after surgery (7.4 ± 1.8 mmHg compared with 31.0 ± 4.7 before surgery). Subsequently, an increase in IOP was noted to 18.3 ± 6.1 during the follow-up period of 1 year. In 17 out of 28 patients (60.7 %), an IOP of less than 18 mmHg was determined, of which 2 were without drug therapy. It was regarded as a “relative” and “absolute” success, respectively. In group II, in the early postoperative period, the dynamics of the decrease in IOP was less pronounced (17.5 ± 3.8 mmHg on the first day after surgery, with a further increase to 26.6 mmHg after a year of follow-up) even against the background of the maximum medication regimen. In the maximum follow-up period, the average number of drugs was used for reducing the IOP in group I was 0.94 ± 0.16, and in group II — 2.28 ± 0.87 (differences are statically significant, p < 0.05). The frequency of “relative” success in group I after 6 months and 1 year of follow-up was significantly higher than in group II (43.4 % versus 25 % and 53.6 % versus 30.6 %, respectively, p < 0.05).

Conclusion. The paper presents the first data in the literature on the comparative analysis of the effectiveness of Preserflo drainage implantation and non-penetrating deep sclerectomy in patients with refractory and repeatedly operated primary open-angle glaucoma. The advantage of the implantation of the Preserflo drainage in relation to the antihypertensive effect and reduction of the number of instillations of antihypertensive drugs have been shown.

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