Anti-Vascular Endothelial Growth Factor Therapy as an Adjunct to Diabetic Vitrectomy

Introduction: The purpose of this work is to study the efficacy of the preoperative intravitreal administration of bevacizumab as an adjunct to vitrectomy in patients with Proliferative Diabetic Retinopathy (PDR). Methods: This retrospective comparative study was performed on 118 eyes (118 patients) with proliferative diabetic retinopathy (PDR), which underwent vitrectomy surgery at the Department of Diabetic Eye Disease at Zarifa Aliyeva National Ophthalmology Centre (Baku, Azerbaijan) in 2015-2019. The main group (the bevacizumab group) included 48 eyes with PDR that received intravitreal administration of bevacizumab (Avastin; Genentech Inc., USA) within one week before vitrectomy; the control group included 70 eyes that did not receive a bevacizumab injection for at least 3 months before the vitrectomy. The minimum follow-up was 12 months. Results: In both groups, complete retinal attachment after primary vitrectomy was achieved in all eyes (100%). Clinically significant intraoperative haemorrhage was observed in the preoperative bevacizumab injection group in 31.2% and the control group- 51.4%, p = 0.030. The preoperative bevacizumab injection reduced the risk of clinically significant haemorrhage by 2.3 times and the need for endodiathermy by 2.7 times (p = 0.031 and p = 0.024, respectively). Early vitreous cavity haemorrhage was observed in 15.0% in the bevacizumab group and in 35.5% in the control group (p = 0.038). The preoperative injection of bevacizumab before vitrectomy reduced the risk of vitreous cavity haemorrhage in the early postoperative period by 3.0 times (p = 0.036). Conclusion: The preoperative use of bevacizumab as an adjunct to diabetic vitrectomy can help reduce the incidence of intraoperative and early postoperative vitreous cavity haemorrhage, which leads to better functional results in the early postoperative period. Over the long-term follow-up period, the effect of the preoperative bevacizumab injections decreases.

Neovascular Glaucoma after Diabetic Vitrectomy: Incidence and Risk Factors

Purpose: The prevalence and risk factors of neovascular glaucoma (NVG) after diabetic vitrectomy were evaluated. Methods: This retrospective study included 171 eyes of 141 patients who underwent diabetic vitrectomy in-hospital between March 2013 and July 2019 and were followed for >12 months postoperatively. Regardless of the presence or absence of neovascularization in the anterior segment, all patients received injections of intravitreal bevacizumab during vitrectomy. Patients with preoperative neovascularization in iris (NVI) or angle (NVA) received both intracameral and intravitreal bevacizumab injections. Data were collected regarding baseline demographics, preoperative best-corrected visual acuity, intraocular pressure, hypertension, NVG in the fellow eye, panretinal photocoagulation history, iris and angle neovascularization, and postoperative findings (e.g., rebleeding and residual retinal detachment). Results: In total, 141 patients and 171 eyes were included in the study, and the incidence of postoperative NVG was 5.85% (10 patients). Five patients (27.78%) with preoperative NVI or NVA developed postoperative NVG. Significant risk factors for postoperative NVG were preoperative NVA or NVI (odds ratio [OR] = 16.428, p = 0.003), shorter diabetic duration (OR = 0.853, p = 0.033), and the absence of preoperative panretinal photocoagulation (OR = 0.006, p = 0.035). Conclusions: There is a high possibility of postoperative NVG in patients with preoperative NVI or NVA, a short duration of diabetes, and no preoperative panretinal photocoagulation. In such patients, close monitoring is required after diabetic vitrectomy.

Topical Umbilical Cord Serum for Corneal Epithelial Defects after Diabetic Vitrectomy

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Intravitreal bevacizumab prior to vitrectomy for proliferative diabetic retinopathy: a systematic review

Background: Diabetic retinopathy is a leading cause of visual loss in the working population. Pars plana vitrectomy has become the mainstream treatment option for severe proliferative diabetic retinopathy (PDR) associated with significant vitreous haemorrhage and/or tractional retinal detachment. Despite the advances in surgical equipment, diabetic vitrectomy remains a challenging operation, requiring advanced microsurgical skills, especially in the presence of tractional retinal detachment. Preoperative intravitreal bevacizumab has been widely employed as an adjuvant to ease surgical difficulty and improve postoperative prognosis.Aims: This study aims to assess the effectiveness of preoperative intravitreal bevacizumab in reducing intraoperative complications and improving postoperative outcomes in patients undergoing vitrectomy for the complications of PDR. Methods: A literature search was conducted using the PubMed, Cochrane, and ClinicalTrials.gov databases to identify all related studies published before 31/10/2020. Prespecified outcome measures were operation time, intraoperative iatrogenic retinal breaks, best-corrected visual acuity in the last follow-up visit, the presence of any postoperative vitreous haemorrhage and the need to re-operate. Evidence synthesis was performed using Fixed or Random Effects models, depending on the heterogeneity of the included studies. Heterogeneity was assessed using Q-statistic and I2. Additional meta-regression models, subgroup analyses and sensitivity analyses were performed as appropriate. Results: Thirteen randomized control trials, with a total of 688 eyes were included in this review. Comparison of the intraoperative data showed that bevacizumab reduced operation time ( p < 0.001), minimized iatrogenic retinal breaks ( p < 0.001), provided better long-term visual acuity outcomes ( p = 0.005), and prevented vitreous haemorrhage ( p < 0.001) and the need for reoperation ( p = 0.001 < 0.05). Findings were strongly corroborated by additional sensitivity and subgroup analyses. Conclusion: Preoperative administration of bevacizumab is effective in reducing intraoperative complications and improving the postoperative prognosis of diabetic vitrectomy. PROSPERO registration number: CRD42021219280

Diabetic Vitrectomy

Diabetic retinopathy (DR) in its advanced stage is a leading cause of blindness and visual impairment. Despite efforts at early detection of DR, disease monitoring, and medical therapy, significant proportions of people living with diabetes still progress to develop the advanced proliferative disease, which is characterized by neovascularization, actively proliferating fibrovascular membranes, and retinal traction. The surgical removal of this proliferating tissue and the treatment of the retinal ischemic drive can be very rewarding, providing significant stability of the retina and in several cases improved retinal anatomy and vision. Diabetic vitrectomy comprises a broad range of surgical techniques and maneuvers, which offer the surgeon and patient opportunity to reverse deranged vitreoretinal anatomy and improve or stabilizes vision. Advances in vitreoretinal technology have contributed greatly to more recent improved outcomes; it is expected that future advances will offer even more benefit.

Topical Umbilical Cord Serum for Corneal Epithelial Defects after Diabetic Vitrectomy

Purpose: To evaluate the role of topical umbilical cord serum (TUCS) therapy in treating corneal epithelial defects (CEDs) after diabetic vitrectomy. Methods: In this double-masked, randomized clinical trial, we included 80 eyes of 80 patients who were candidates for vitrectomy due to proliferative diabetic retinopathy complications. In cases of corneal edema obscuring the fundus view during surgery, the corneal epithelium was removed using a 6-mm trephine and a blade no.15. The day after the surgery, patients were randomly divided into two groups: (1) the TUCS group that received 20% TUCS six times/day in addition to the conventional treatment of CED and (2) the control group, which was prescribed artificial tears as placebo in addition to the conventional treatment of CED. The rate of healing of CEDs was measured via two maximum linear dimensions perpendicular to each other at the start of therapy and on postoperative days 1–5, 7, and 12. Results: Of 80 eyes, 40 were assigned to each treatment group. The mean times to complete CED healing were 2.4 ± 0.7 and 3.8 ± 2.1 days in the TUCS and control groups, respectively (P < 0.001). Persistent CED occurred in two eyes in the control group but in no eyes in the TUCS group. Conclusion: TUCS therapy may be safe and effective in healing CEDs after vitrectomy in patients with diabetes.