Long-term filtration and visual field outcomes after primary glaucoma triple procedure with and without mitomycin-C

Abstract

Objective: To evaluate the long-term effectiveness of glaucoma management in patients undergoing primary glaucoma triple procedure (PGTP) with and without adjunctive subconjunctival mitomycin-C (MMC).

Design: Case-controlled study.

Participants: Of the 203 eyes of 203 primary open-angle glaucoma (POAG) patients who had undergone PGTP and in whom reliable Humphrey visual fields had been obtained both before and after surgery at 13.5 +/- 8.9 and 27.9 +/- 8.9 months, 124 of the 144 eyes that received MMC during surgery were matched to the other 59 eyes that did not with respect to cup-to-disc ratio and risk factors for filtration failure in addition to other variables.

Main outcome measures: Both preoperative and postoperative intraocular pressure (IOP), Humphrey visual fields and their global indices, number of glaucoma medications, and best-corrected visual acuity (BCVA).

Results: There were no significant differences in demographics between the two groups (P > 0.05 for each). Whereas both the control and the MMC groups attained significant decreases of mean IOP (18.5 +/- 5.7 mmHg-;15.6 +/- 4.6 mmHg, P = 0.0014; 19.3 +/- 7.0 mmHg-13.7 +/- 4.9 mmHg, P = 0.0001) and mean number of medications (2.1 +/- 1.3-1.3 +/- 1.3, P = 0.0001; 2.3 +/- 1.2-1.0 +/- 1.3, P = 0.0001) at 36 months after surgery, the MMC group had significantly lower mean IOP than the control group at all postoperative visits (P < 0.05 for each). The MMC group also tended to have less medical dependency after surgery than the control group. There was no significant difference in postoperative BCVA between the two groups. Patients in both groups had mean visual acuity of 20/30 or better. There was a significant worsening of corrected pattern standard deviation (CPSD) in the control group (3.97 +/- 3.18-5.17 +/- 3.36, P = 0.001) compared with no significant change in the MMC group (5.07 +/- 4.11-5.23 +/- 3.36, P = 0.93). The mean deviation did not change significantly in either group.

Conclusions: The long-term glaucoma management in POAG patients with cataract undergoing PGTP indicates a successful outcome in final IOP, medical dependency, and BCVA. Furthermore, the MMC group had better IOP control and stable visual fields (CPSD), whereas the control group had a significant worsening of CPSD.