Effect of mitomycin C for combined trabeculectomy and phacoemulsification

Background. To evaluate the efficacy and safety of intraoperative mitomycin C (MMC) for trabeculectomy combined with phacoemulsification (phacotrab) in patients with coexisting glaucoma and cataract. Methods. We retrospectively reviewed the charts of consecutive patients who underwent phacotrab from July, 1996, to March, 1998. The pre- and postoperative intraocular pressure (IOP), number of glaucoma medications, visual acuity (VA), and postoperative complications were compared among 22 patients (22 eyes) who received intraoperative MMC and 18 patients (18 eyes) who did not receive MMC, served as the control group. Data of age, gender, type of glaucoma, number of glaucoma medications, cup-to-disc ratio of the optic nerve and the extent of visual field defects were also evaluated. Kaplan- Meier survival analysis was used to compare the surgical success rates between two groups. Results. The mean IOP decreased from 16.1 ± 4.2 mmHg to 10.94 ± 3.6 mmHg in the MMC group, and from 18.7 ± 6.9 mmHg to 14.6 ± 1.9 mmHg in the control group at one year of follow-up. The mean postoperative IOPs were significantly lower in the MMC group than in the control group at one week, two weeks, and one, two, nine and 12 months. Postoperative mean VA log₁₀ minimum angle of resolution (MAR) improved significantly in both groups. The mean number of medications decreased from 1.91 ± 0.75 to 0.18 ± 0.50 in the MMC group, and from 1.89 ± 0.47 to 0.72 ± 0.75 in the control group (p < 0.001 for both). The one-year complete success rate was significantly higher in the MMC group (p = 0.0038) than in the control group. No major complication was found throughout the study. Conclusions. Intraoperative MMC in phacotrab may improve postoperative filtration with less dependence on glaucoma medication. No significant adverse effects were associated with MMC application.