Should an iridectomy be routinely performed as a part of trabeculectomy? Two surgeons' clinical experience

To investigate the effects of performing peripheral iridectomy on the outcome of trabeculectomy.

Retrospective chart review of the medical records of 75 patients (75 eyes) who underwent trabeculectomy surgery, with or without peripheral iridectomy, who had been followed for more than 1 year. Data were collected preoperatively, 1 day postoperatively, on days 30-90 postoperatively, and 1-3 years postoperatively. The collected data included visual acuity, intraocular pressure, bleb development, postoperative inflammation, and complications. Thirty-six eyes (48%) had cataract extraction at the time of trabeculectomy. A peripheral iridectomy was performed in 43 cases (57%). Student's t-test was used for the statistical analyses.

Patients having peripheral iridectomy had more inflammation on days 30-90 than those who did not have peripheral iridectomy performed (in patients having cataract extraction with trabeculectomy (P=0.018) and those not having cataract extraction (P=0.038)). There was no statistically significant difference in intraocular pressure in eyes with or without iridectomy. Postoperative complications were rare in both groups but greater in number in the eyes with peripheral iridectomy.

Trabeculectomy performed without peripheral iridectomy appears to be as effective in lowering intraocular pressure as when performed with peripheral iridectomy, but it is a safer procedure, with a lower incidence of postoperative inflammation. It may be an advantage to avoid performing peripheral iridectomy during trabeculectomy in eyes that are not predisposed to postoperative shallowing of the anterior chamber or pupillary block.