Background: The aim of this retrospective study is to evaluate the difference in postoperative intraocular pressure (IOP) control, number of antiglaucoma medications and visual acuity (VA) between combined phacoemulsification and trabeculectomy (Glaucoma triple) surgery and two-stage procedures with trabeculectomy first and cataract extraction later.
Patients and methods: Two groups of glaucoma patients were assessed: In group 150 consecutive patients undergoing combined phacoemulsification and trabeculectomy were enrolled. In group two, 51 consecutive patients were included, that had undergone trabeculectomy first and cataract surgery later. The mean interval between the two procedures was 3.2 years, 35/51 patients (71%) underwent conventional extracapsular cataract extraction, the other 16 patients (29%) had phacoemusification via clear cornea incision.
Results: One year postoperative both groups revealed a significant IOP reduction. IOP-reduction was significantly better in the two-stage group one year after trabeculectomy (12.8 +/- 4.0 mm Hg) and one year after cataract extraction (14.0 +/- 2.8 mm Hg) as compared to the combined surgery group (15.3 +/- 4.0 mm Hg). Kaplan-Meier survival analysis revealed a 90% success-rate 12 months after trabeculectomy only as compared to 65% success-rate in the combined surgery group. The number of antiglaucoma medications was significantly reduced in both groups. One year after cataract surgery no difference in VA could be seen between the two groups.
Conclusions: If medically uncontrolled glaucoma with advanced optic nerve head changes in patients with coexisting glaucoma and cataracts is the main indication for surgery, a two-stage procedure (i.e. trabeculectomy first, cataract extraction later) yields better long-term IOP control. If glaucoma is medically controlled with a simple regimen, conjunctiva-sparing cataract surgery may be the treatment of choice. In all other cases of coexisting glaucoma and cataract combined phacoemulsification and trabeculectomy (Glaucoma triple) is preferrable, either performed through a single incision or as two separate procedures in the same session (i.e. trabeculectomy from above, phacoemulsifiaction via clear cornea from temporal).