Slow-Release Dexamethasone in Proliferative Vitreoretinopathy
Ophthalmology, June 2017
Recurrent retinal redetachment may occur after procedures for detachments that are accompanied by proliferative vitreoretinopathy (PVR), and efforts to identify a single effective adjunct treatment have been unsuccessful. In the first randomized controlled trial of a slow-release corticosteroid implant for treatment of PVR, Banerjee et al. examined the effect of dexamethasone on outcomes of vitreoretinal surgery for detachments complicated by PVR. Although the treatment did not improve the anatomic outcome, it appeared to lower the rate of postoperative cystoid macular edema (CME).
In this 2-year, prospective, double-masked trial, 140 adults with PVR undergoing pars plana vitrectomy with silicone oil tamponade for recurrent retinal detachment received either standard care (control group [no adjunct], n = 70) or injection of 0.7 mg of slow-release dexamethasone (Ozurdex) at the time of vitrectomy and when the silicone oil was removed (adjunct group, n = 70). The primary outcome measure was stable retinal reattachment at the time of oil removal, without need for additional vitreoretinal surgery during the subsequent 6 months. Secondary outcomes included final visual acuity, CME occurrence, foveal thickness, macular volume, and other endpoints.
The proportion of patients who met the primary outcome was similar for the 2 study arms (adjunct, 49.3%; control, 46.3%; p = .733). However, the implant had a limited favorable effect on the CME rate at 6 months (adjunct, 42.7%; control, 67.2%; p = .004). Fewer patients in the adjunct group had central foveal thickness >300 μm (47.6% vs. 67.7%; p = .023).
Visual acuity at 6 months was comparable for the study groups. The fact that it was not better in the adjunct group suggests that a pathologic process other than macular edema is responsible for the poor visual outcome in patients with PVR.
The investigators concluded that slow-release dexamethasone does not improve the proportion of stable retinal reattachment but may be somewhat protective against CME. They recommended that studies be performed, aimed at improving anatomic and functional outcomes, testing other adjunct treatments, and establishing the cause of visual loss in eyes with PVR.
The original article can be found here.