Abstract
The Paul Glaucoma Implant (PGI) is becoming increasingly used in many countries. The primary aim of this study was to identify the most important pre-, intra- and post-operative factors associated with successful intraocular pressure (IOP) control at one year. A total of two hundred and fifty -one eyes from 239 glaucoma patients undergoing PGI surgery were included in this prospective, multicentre, longitudinal study. Clinical data were collected on a REDCap platform using a standardised surgical protocol. Variables were recorded pre-, intra- and postoperatively. Univariable and multivariable logistic regression were used to identify predictors of complete success at one year. These results are expressed as Odds Ratios (OR) and their 95% confidence intervals (95% CI). Kaplan-Meier survival analysis was also performed. Mean IOP was significantly reduced from 25.3 ± 8.8 mmHg preoperatively to 13.1 ± 3.9 mmHg at one year (p < 0.001). The medication burden decreased from 3.03 ± 1.12 to 0.78 ± 0.96 (p < 0.001). Most complications were minor and self-limiting. Factors associated with complete success in univariable or multivariable analysis were: use of intraoperative antimetabolites (mitomycin or 5-fluorouracil) [OR 2.59; 95% CI 1.18-5.67], combined phacoemulsification-PGI surgery [OR 4.38; 95% CI 1.10-17.36] and removal of the ripcord after 4-5 months [OR 2.36; 95% CI 1.07-5.18]. High myopia was only associated in the univariable analysis (OR 0.50; CI 0.30-0.85; p = 0.010). Previous glaucoma surgery, hypertensive phase, surgeon experience and diagnosis of non-open angle glaucoma were not significantly associated with complete success. This study concluded that the effectiveness of the PGI can be enhanced by implementing certain strategies that have not shown similar benefits in Ahmed or Baerveldt glaucoma devices.