JUL 27, 2009
In this investigation, researchers in Tokyo found that administering a sub-Tenon injection of triamcinolone acetonide at the end of trabeculetomy surgery produced minimal benefits for patients with secondary forms of glaucoma. Although the eyes that received steroid injections had statistically fewer argon laser suture lysis procedures, after 12 months the study and control groups had essentially identical results in terms of IOP, number of glaucoma medications, morphologic bleb appearance, rate of success and postoperative complications.
Forty-eight patients participated in the study, with 26 eyes randomly assigned to undergo trabeculectomy with intraoperative sub-Tenon triamcinolone injection and 27 eyes to trabeculectomy only. Treatment success was defined by the authors as IOP of 21 mm Hg or less and IOP reduction of at least 20 percent without the use of antiglaucoma medication.
It should be noted that all patients received intraoperative mitomycin C and topical steroid drops after surgery, so the effect of sub-Tenon triamcinolone may have been masked by these other interventions. It may be that a sub-Tenon steroid injection could replace the need for postoperative topical steroids. In addition, specific types of secondary glaucoma, such as those associated with uveitis or post-penetrating keratoplasty, may benefit from the sub-Tenon triamcinolone; however, the sample size of this study was too small for subgroup analysis. This study shows again that although trabeculectomy surgery is far from perfect, even incremental improvements in this procedure are difficult to achieve.
Dr. WuDunn is a consultant to Alcon Laboratories, Inc., and receives lecture fees from Pfizer Ophthalmics.