Midterm Follow-up Results of Combined Phacoemulsification, Lens Implantation, and Mitomycin-C Trabeculectomy Procedure

Abstract

This study evaluates the visual, refractive, perimetric, and intraocular pressure (IOP) results following combined phacoemulsification, lens implantation, and trabeculectomy with mitomycin-C. Twenty-nine consecutive eyes of 26 patients with cataract and glaucoma that had undergone combined phacoemulsification, posterior chamber lens implantation, and limbus-based trabeculectomy with mitomycin-C applied after the cataract removal and trabeculectomy had a minimal follow-up time of 12 months (mean follow-up 20 +/- 6.3 months). Each eye was evaluated for visual acuity, corneal astigmatism, IOP, bleb persistence, optic nerve stability, visual field status, and complications. Goldmann visual fields were assessed by a semi-quantitative method and threshold static perimetry by statistical indices of diffuse damage (mean deviation) and focal loss (corrected pattern standard deviation). The preoperative and postoperative results were compared by Student's t-test. All eyes that were free of pre-existing macular disease demonstrated significant improvement in visual acuity by at least 4.5 lines of Snellen acuity. Postoperative astigmatism was negligible (0.29 diopters). The average IOP reduction was 6.5 mm Hg, with the one year or more average of 13.4 mm Hg on virtually no antiglaucoma medicines (0.2 +/- 0.5). Functioning filtering blebs persisted in 86% of eyes. Of 11 patients tested with pre- and postoperative Goldmann perimetry, only two showed visual field defect progression despite IOPs < 15 mm Hg. Of the 12 eyes with pre- and postoperative static threshold perimetry, the mean deviation deteriorated in nine eyes (p = 0.003). The corrected pattern standard deviation changes were not statistically significant (p = 0.69). Complications (including two cases of late-onset endophthalmitis) were comparable with other studies reporting filtration surgery with adjunctive antimetabolites. We detected no untoward effects of applying the mitomycin at the end of the procedure rather than at the beginning. The combined procedure technique that we describe appears to be effective at restoring visual acuity and significantly reducing IOP. Nevertheless, many visual fields showed continued, diffuse glaucomatous progression in the year or two following surgery and the development of late endophthalmitis in two eyes is a concern.