Intravitreal Bevacizumab for Diabetic Retinopathy

Abstract

Diabetic retinopathy (DR) remains the major threat to sight in the working age population. Diabetic macular edema (DME) is a manifestation of DR that produces loss of central vision. Macular edema within 1 disk diameter of the fovea is present in 9% of the diabetic population. Proliferative diabetic retinopathy (PDR) is a major cause of visual loss in diabetic patients. In PDR, the growth of new vessels from the retina or optic nerve, is thought to occur as a result of vascular endothelial growth factor (VEGF) release into the vitreous cavity as a response to ischemia. Furthermore, VEGF increases vessel permeability leading to deposition of proteins in the interstitium that facilitate the process of angiogenesis and macular edema. This review demonstrates multiple benefits of intravitreal bevacizumab on DR including DME and PDR. The results indicate that intravitreal bevacizumab injections may have a beneficial effect on macular thickness and visual acuity (VA), independent of the type of macular edema that is present. Therefore, in the future this new treatment modality could replace or complement focal/grid laser photocoagulation in DME. In addition, in PDR, this new option could be an adjuvant agent to PRP so that more selective therapy may be applied.

A review of anti-VEGF agents for proliferative diabetic retinopathy

“…24 Anti-VEGF treatment and safety Dosage and frequency of anti-VEGF treatment in PDR cases The optimal dose and dosing sequence for bevacizumab remains unclear. Most studies have used a dose of 1.25 mg. [25][26][27][28][29] Arevalo and Garcia-Amaris 30 used dosages of 1.25 mg (20.5%) and 2.5 mg (79.5%) bevacizumab, depending on the discretion of the treating clinician, and noted that the 2.5-mg dose was more effective in inducing complete regression of neovascularization relative to the 1.25-mg dose in the treatment of naive eyes.…”

“…Most studies deferred re-injections to cases that only showed recurrence. 30 Effectiveness of dose 1.25 mg bevacizumab at regression of neovascularization: level of evidence IV.…”

Suitability and Repeatability of a Photostress Recovery Test Device, the Macular Degeneration Detector (Mdd-2), for Diabetes and Diabetic Retinopathy Assessment

“…12 The possibilities for retarding disease progression including recent advances in pharmacologic management of diabetic maculopathy, best applied at the earliest stages of the development of abnormal pathology, further increase the priority that should be afforded to effective disease monitoring. [13][14][15] Diabetic maculopathy is the most common cause of visual loss in diabetic patients. Visual acuity represents the most widely used test of visual, and in particular macular, function.…”

Diabetic Retinopathy: Understanding Pathologic Angiogenesis and Exploring its Treatment Options

“…In ophthalmology, the use of bevacizumab has grown due to its significant lower price when compared with the previous molecules. Its use in diabetic retinopathy has also grown with promising results in proliferation and macular edema [111][112][113] and in the clearing of vitreous hemorrhages [114]. It has shown effectiveness in neovascular glaucoma secondary to ischemic retinal diseases including diabetic retinopathy [37].…”

“…This is especially important in situations of vitreous hemorrhage. Even though some authors use intravitreal bevacizumab as the first line agent in selected cases of diabetic retinopathy [113] including diabetic macular edema [13], it is still early to recommend at the moment, anti-VEGF therapy without laser therapy outside clinical trial settings.…”