Long-term effects of simultaneous subconjunctival and subscleral mitomycin C application in repeat trabeculectomy.
OBJECTIVE
To assess the efficacy and safety of simultaneous mitomycin C application under conjunctival and scleral flaps in patients with repeat trabeculectomy.


METHODS
A total of 44 patients (44 eyes) with previous failed filtering surgery were randomized to one of two groups. The both-flaps group comprised 22 patients (22 eyes) with trabeculectomy and intraoperative mitomycin C application under conjunctival and scleral flaps, whereas the subconjunctival group comprised 22 patients (22 eyes) with subconjunctival application of mitomycin C. Particular attention was paid to intraocular pressure, postoperative medications, visual acuity, filtering bleb appearance, and complications. The mean follow-up time was 38.18 +/- 12.48 months.


RESULTS
The mean preoperative intraocular pressure decreased from 39.1 +/- 7.3 mm Hg to the postoperative level of 15.6 +/- 4.8 mm Hg in the both-flaps group (P = 0.014), and from 39.4 +/- 8.4 to 18.7 +/- 5.8 mm Hg in the subconjunctival group (P = 0.018). There was a statistically significant difference in intraocular pressure at all follow-up times, except at 1 week and 1 month postoperatively. Kaplan-Meier survival analysis showed there was no significant difference in total success rate (complete plus qualified success) between the two groups (P = 0.622, log-rank test). However, the two survival curves for the complete success subgroups (without additional medications) confirmed that mitomycin C applications under both flaps had a higher success rate than subconjunctival application (P = 0.043, log-rank test). No statistically significant difference in medications was present between the two groups, and no severe complications developed in either group.


CONCLUSIONS
Trabeculectomy augmented with mitomycin C application at both sites could produce a greater lowering of intraocular pressure with low incidence of postoperative complications, and could provide an increased chance of long-term success. The procedure is effective and safe in patients with repeat trabeculectomy.
You
Yi-an
YA
Department of Ophthalmology, First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China.
Gu
Yang-shun
YS
Fang
Chun-ting
CT
Ma
Xiao-qin
XQ
D000328:Adult; D000368:Aged; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage*; D003131:Combined Modality Therapy; D003228:Conjunctiva / Q000187:drug effects*; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000188:drug therapy* / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage*; D011446:Prospective Studies; D012086:Reoperation; D012449:Safety; D012590:Sclera / Q000187:drug effects*; D014130:Trabeculectomy
D000903:Antibiotics, Antineoplastic; D016685:Mitomycin