The adjunctive use of pre-operative intravitreal bevacizumab in the setting of proliferative diabetic retinopathy

Comparison of efficacy of combination therapy of an Intravitreal injection of bevacizumab and photocoagulation versus Pan Retinal Photocoagulation alone in High risk Proliferative Diabetic Retinopathy

Objective:

To compare efficacy of intravitreal bevacizumab augmented with Panretinal photocoagulation versus Panretinal photocoagulation alone in high risk proliferative diabetic retinopathy.

Methods:

This is Randomized clinical control trial study conducted at ISRA University Hospital, Hyderabad from July 2018 to December 2018. A total of 76 eyes were randomized into two groups, 38 eyes undergone PRP plus intravitreal bevacizumab, while 38 eyes had PRP alone. Status of neovessels was assessed before and after treatment with the help of fundus fluorescein angiography. Neovessels at disc (NVD’s) and neovessels elsewhere (NVE’s) were assessed with the disc surface diameter.

Results:

Seventy-six eyes were enrolled in this randomized clinical trial into two groups consecutively, that all completed the six months follow-up. In the PRP group mean BCVA (logMAR) worsened significantly from mean 0.30±0.07 to mean 0.40±0.04 at a 30^th day and mean 0.40±0.04 at day 90. While BCVA become improved from 0.30±0.05 to 0.1±0.03 at week four and 0.1±0.02 at week 12 in PRP-Plus group. There was significant change in regression of NVES in PRP only group at week 4 is 2.25±0.75 (p=0.00004) and at 12 weeks 2.00±0.50 (p=0.00002), while in PRP + intravitreal bevacizumab group at 4^th week was 1±0.5 (p =0.0001) and at 12^th week was 0.75±0.25 (p=0.0001).

Conclusion:

Intravitreal Bevacizumab augmented with PRP is more effective in early regression of neovessels in high risk PDR patients.

Surgical management of diabetic tractional retinal detachments

Tractional retinal detachment is an end-stage form of diabetic retinopathy that occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. We review the literature related to the management of this disease. Preoperative planning includes appropriate patient selection, diagnostic and prognostic imaging, and medical optimization with reduction of systemic risk factors. Use of antivascular endothelial growth factor for preoperative treatment has had significant benefits for tractional retinal detachment repair in improving surgical efficiency and outcomes. Advances in microsurgical instrumentation are discussed, with attention to small-gauge vitrectomy with improved flow dynamics, viewing strategies, and lighting allowing bimanual surgery. Special emphasis is placed on bimanual surgical technique, choice of tamponade, and the avoidance of iatrogenic damage. Complications and special considerations are further explored. Based on our compilation of relevant literature, we propose a surgical algorithm for the management of these complex patients.

Lymphatic Vascular Structures: A New Aspect in Proliferative Diabetic Retinopathy

Diabetic retinopathy (DR) is the most common diabetic microvascular complication and major cause of blindness in working-age adults. According to the level of microvascular degeneration and ischemic damage, DR is classified into non-proliferative DR (NPDR), and end-stage, proliferative DR (PDR). Despite advances in the disease etiology and pathogenesis, molecular understanding of end-stage PDR, characterized by ischemia- and inflammation-associated neovascularization and fibrosis, remains incomplete due to the limited availability of ideal clinical samples and experimental research models. Since a great portion of patients do not benefit from current treatments, improved therapies are essential. DR is known to be a complex and multifactorial disease featuring the interplay of microvascular, neurodegenerative, metabolic, genetic/epigenetic, immunological, and inflammation-related factors. Particularly, deeper knowledge on the mechanisms and pathophysiology of most advanced PDR is critical. Lymphatic-like vessel formation coupled with abnormal endothelial differentiation and progenitor cell involvement in the neovascularization associated with PDR are novel recent findings which hold potential for improved DR treatment. Understanding the underlying mechanisms of PDR pathogenesis is therefore crucial. To this goal, multidisciplinary approaches and new ex vivo models have been developed for a more comprehensive molecular, cellular and tissue-level understanding of the disease. This is the first step to gain the needed information on how PDR can be better evaluated, stratified, and treated.

Effect of intravitreal conbercept treatment before vitrectomy in proliferative diabetic retinopathy

AIM

To evaluate the safety and efficacy of intravitreal conbercept (IVC) injections as pretreatment for pars plana vitrectomy (PPV) in severe proliferative diabetic retinopathy (PDR).

METHODS

This was a retrospective chart review of all patients who underwent PPV for PDR from January 2014 to October 2016. Patients who underwent IVC injection before PPV were assigned to the IVC group; the others were assigned to the control group. The IVC was performed 3-7d before surgery in the IVC group. All the eyes in the two groups were operated by the same doctor to complete the vitrectomy. Intraoperative complications and the changes in best-corrected visual acuity (BCVA) before and after surgery were compared between the two groups.

RESULTS

A total of 68 eyes of 63 patients (22 eyes in the IVC group and 46 eyes in the control group) were examined. The risk of intraoperative bleeding was lower in the IVC group (2/22) than in the control group (25/46, P=0.000). Furthermore, the use of endodiathermy was significantly lower in the IVC group (1/22) than in the control group (12/46, P=0.047). The surgical time in the IVC group (112.64±34.52min) was significantly shorter than in the control group (132.85±40.04min, P<0.05). Compared to the BCVA before surgery, the mean BCVA was significantly improved after surgery for both groups (P<0.05).

CONCLUSION

PPV is an effective treatment and can improve vision in patients with PDR. Preoperative intravitreal injection of conbercept could reduce the chances of intraoperative bleeding and the use of endodiathermy and shorten the operative time, which are beneficial in the management of PDR.