Current management of diabetic tractional retinal detachments

Abstract

Twenty-five percent of diabetes-related vision loss stems from complications of proliferative diabetic retinopathy (PDR). Panretinal photocoagulation has been the preferred treatment of high-risk PDR for decades and more recently intravitreal injections of drugs that inhibit the actions of vascular endothelial growth factor have become popular. But despite these treatments PDR may progress uncontrollably to advanced pathologies such as traction retinal detachments (TRDs), combined traction/rhegmatogenous retinal detachments (TRD/RRDs), vitreous hemorrhages, rubeosis iridis, and traction maculopathies, which produce mild-to-severe loss of vision. TDR have long been the most common indication for PDR-related vitreoretinal surgery. Vitrectomy surgery is indicated for recent (<6 months duration) TRD involving the macula, progressive TRD that threatens the macula, and recent data suggest that chronic macula-involving TRDs (>6 months duration) may also benefit. Combined TRD/RRD represents a particularly challenging surgical condition but advances in surgical instrumentation, dissection techniques, and post-operative tamponade have produced excellent success rates. The recent development of small-gauge vitrectomy systems has persuaded most surgeons to switch platforms since these appear to produce shorter surgical times and quicker post-operative recoveries. Pre-operative injections of bevacizumab are frequently administered for persistent neovascularization to facilitate surgical dissection of pre-retinal fibrosis and reduce the incidence of post-operative hemorrhages. Recent trends toward earlier surgical intervention and expanded indications are likely to continue as surgical instrumentation and techniques are further developed.

Keywords: Diabetes; diabetic retinopathy; tractional retinal detachment; vitrectomy.

Figure 1

This traction/rhegmatogenous retinal detachment involves the entire temporal retina. Note the bullous or convex configuration of the retina and the extension of the detachment to the ora serrata

Figure 2

One month after vitrectomy surgery with the use of silicone oil, the retina remains completely flat. A retinal break could not be identified pre-operatively but during surgery a full-thickness retinal hole was found superotemporal to the macula. Six months later, the best corrected visual acuity was 20/400, compared to counting fingers @ 4’ pre-operatively

Figure 3

Traction retinal detachment of the left eye of a 32-year-old patient with type 1 diabetes mellitus. The visual acuity was 20/160. The right eye was blind for the past 5 years following failed surgery for traction retinal detachment elsewhere. Pre-retinal fibrous plaques are present inferior to the macula and along the superotemporal arcade. Some pre-retinal hemorrhage is present. Panretinal photocoagulation scars are present

Figure 4

Appearance of the fundus 7 months after vitrectomy, membrane peeling, supplemental laser photocoagulation, and silicone oil injection because of an iatrogenic retinal break at the time of surgery. The visual acuity is 20/50. Not all of the fibrous plaques were removed at the time of surgery. It was judged that more aggressive peeling, sectioning, and attempts at removal would cause more iatrogenic retinal breaks. This is a common intraoperative judgment that must be made

Figure 5

Pre-operative (top) and post-operative (bottom) optical coherence tomography images in the case of traction retinal detachment involving the macula shown in Figures 1 and 2. The yellow arrow shows subfoveal fluid pre-operatively and the fluid is gone post-operatively. The pink arrow shows loss of the foveal depression in the post-operative macula, which is a common finding. The blue arrow shows the light reflex at the silicone oil-retina interface

Figure 6

This extrafoveal tractional retinal detachment is characterized by fibrosis with complete involution of neovascular vessels. No progression of the detachment occurred during the course of 2 years

Figure 7

This extrafoveal traction retinal detachment has created traction lines through the fovea, giving the patient metamorphopsia. Vitrectomy was performed because of the visual symptoms

Figure 8

This fovea-involving traction retinal detachment is accompanied by active neovascularization. Bevacizumab was injected intravitreally 3 days prior to surgery to decrease the risk of intraoperative bleeding