Slow-Release Dexamethasone in Proliferative Vitreoretinopathy: A Prospective, Randomized Controlled Clinical Trial
Banerjee PJ, Quartilho A, Bunce C, et al
Ophthalmology. 2017 Feb 22. [Epub ahead of print]
Reports for the use of steroids in the management of proliferative vitreoretinopathy (PVR) are inconsistent. The advent of a sustained-release implant that can release dexamethasone for 3-4 months in the vitreous cavity has renewed interest in studying the role of steroids for PVR.
Study Summary
Banerjee and colleagues report on a study of the dexamethasone implant in PVR. One hundred forty patients with grade C PVR and retinal detachment were randomly assigned 1:1 to receive or not receive (control group) the implant during vitrectomy. The primary outcome was the proportion of patients who had a reattached retina with removal of silicone oil, without additional vitreoretinal surgical intervention at 6 months.
In the intervention group, one dexamethasone implant was placed at the time of vitrectomy and oil, and the second implant was placed at the time of oil removal. The implant group and the control group were balanced in regard to baseline characteristics (eg, previous surgery, extent of retinal detachment). Operative techniques used similar rates of retinectomy and membrane peeling.
Results showed that both groups had a similar primary outcome (49.3% vs 46.3% reattachment, intervention vs control). Of the secondary outcomes studied (eg, cataract surgery, macular edema, retinal thickness, hypotony, recurrent membrane proliferation), those receiving the implant had less macular edema than controls (42.7% vs 67.2%). Despite observing a difference in rates of postoperative macular edema, the authors did not observe any difference in visual acuity at 6 months.
Viewpoint
This randomized clinical trial is very important because it studied the effect of long-term dexamethasone administration on PVR. Steroids have been used in various forms for PVR (eg, intravitreal triamcinolone, subtenon triamcinolone, intravitreal dexamethasone infusions during vitrectomy, systemic prednisone). It was designed to have a power of 85% to detect, at the 5% level, a 50% improvement in success of the dexamethasone implant regimen (ie, reducing failure from 49% to 24%). If the trial had met its primary endpoint, this reduction in failure rate would have been of sufficient magnitude and clinical significance to change clinical practice. It is possible that there could be a smaller difference between the two groups, which was not statistically significant. Meanwhile, the quest continues for a pharmacologic adjunct to prevent PVR recurrence.
Abstract
Medscape Ophthalmology © 2017 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: Proliferative Vitreoretinopathy and Steroid Implants -- A Good Fit? - Medscape - Apr 13, 2017.
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