Abstract
Purpose: :
To assess the efficacy and complications of trabeculectomy with a biodegradable implant (OlogenTM implant) versus trabeculectomy using mitomycin C (MMC) in patients with medically uncontrolled open angle glaucoma in a prospective randomised trial.
Methods: :
In the MMC group (A) trabeculectomy was done according to standard protocols. In the OlogenTM group (B) after standard trabeculectomy the implant was positioned on top of the scleral flap and no mitomycin C was applied. Follow-up was continued for 12 months after surgery and included testing of intraocular pressure (IOP), visual acuity (VA), visual field (VF), ultrasound biomicroscopy (UBM), and filtering bleb score.
Results: :
The mean preoperative IOP was 24.8 (SD 8.9) mmHg for all patients enrolled. One year after surgery the mean IOP was 15.6 (SD 2.4) mmHg in the OlogenTM group (p<0.01, 43 % reduction) and 11.5 (SD 4.1) mmHg in the MMC group (p<0.01, 50 % reduction). No antiglaucomatous medication was necessary in the MMC group in the first year of follow-up, whereas 5 patients in the OlogenTM group required topical treatment. The absolute success rate, defined as an IOP lower than 18 mmHg and a decrease in IOP of at least 20 % in relation to the preoperative IOP value without topical antiglaucomatous medication, was 100 percent in the MMC group and 50 percent in the OlogenTM group (p = 0.01). After one year filtering blebs developed significantly more avascular areas in the MMC group (score = 1.4) than in the OlogenTM group (score = 2.8; p < 0.01). MMC blebs (score = 1.8) showed significantly more microcysts than blebs in the OlogenTM group (score = 1.0; p = 0.02).
Conclusions: :
The complete success rate using trabeculectomy with the OlogenTM implant is lower than that achieved by trabeculectomy with mitomycin C. However, the bleb morphology caused more problems in the MMC group (avascularity score). Further modifications of the Ologen implant will be necessary to improve the functional outcome.
Clinical Trial: :
www.clinicaltrials.gov NCT00538590
Keywords: wound healing • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials