Severe Proliferative Diabetic Retinopathy
|Diabetic Retinopathy||Procedure: vitrectomy Procedure: panretinalphotocoagulation|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Participant)
Primary Purpose: Treatment
|Official Title:||Severe Proliferative Diabetic Retinopathy Treated With Vitrectomy or Panretinal Photocoagulation: a Prospective Comparative Study|
|Study Start Date:||October 2001|
|Primary Completion Date:||October 2006 (Final data collection date for primary outcome measure)|
90 eyes of 90 patients, with severe PDR, some with tractional retinal detachment (TRD) not involving the macula were included in the study and treated with vitrectomy
The surgical technique (Group 1) included vitrectomy, with a combination of delamination and segmentation of gliotic tractional membranes using bimanual technique. Silicone oil tamponade was used in eyes with long-standing tractional retinal detachment, as deemed necessary by the surgeon, or in eyes in which a retinal break occurred during the vitrectomy.
panretinalphotocoagulation (group 2)
90 eyes of 90 patients, with severe PDR, some with tractional retinal detachment (TRD) not involving the macula were included in the study and treated with panretinalphotocoagulation
Panretinal photocoagulation was completed according to guidelines summarized in ETDRS with extensive full subconfluent panretinal photocoagulation.
The utility and practice of Panretinalphotocoagualtion (PRP) in patients with high-risk Proliferative Diabetic Retinopathy (PDR) have not changed since the ETDRS reported guidelines in 1987. A meta-analysis of the DRS and ETDRS two large U.S. RCT of laser therapy for PDR confirmed the effectiveness of PRP (Level I evidence). Both trials had large sample sizes, excellent compliance and adequate follow-up. These studies established that PRP reduces the risk of severe visual loss in patients with high-risk PDR by 50% to 60%20.
With the arrival of the vitrectomy, this surgery was often used to treat eyes with severe complications from PDR. The most common indications for vitrectomy were nonclearing vitreous hemorrhage, Tractional Retinal Detachment(TRD) with macular involvement, and combined traction and rhegmatogenous retinal detachment. With the addition of new indications to the known indications vitrectomy has been performed in earlier stages(severe PDR). A large number of case series reports have assessed the effect of pars plana vitrectomy on diabetic TRD with or without macular detachment but the level of evidence was low and they included patients not homogeneous. These studies have generally shown benefit, with improved vision seen in many patients (ranging from 22% to 65%) but they have also indicated a high rate of operative and postoperative complications. These numerous intra and post-operative complications could lead to satisfying anatomical results but poor vision.The purpose of this study is to examine and compare, prospectively, best corrected visual acuity (BCVA) outcomes and complications of a cohort of patients with Proliferative Diabetic Retinopathy and Tractional Retinal Detachment not involving macula undergoing pars plana vitrectomy (PPV) or conventional management (panretinal photocoagulation)
Please refer to this study by its ClinicalTrials.gov identifier: NCT01115257
|1Department of Medicine and Surgery, Section of Ophthalmology, Santa Marta Hospital, University of Catania, Italy|
|Catania, Italy, 95100|
|Study Chair:||Teresio Avitabile, Professor||universita studi di Catania|