Deep Sclerectomy versus Punch Trabeculectomy: Effect of Low-Dosage Mitomycin C

Abstract

Purpose: To compare IOP behavior after deep sclerectomy (DS) and trabeculectomy with the Crozafon-De Laage Punch (TP), using low-dosage intraoperative mitomycin C (MMC) in both techniques. Methods: The study was a prospective randomized clinical trial. All patients met inclusion and exclusion criteria, and were scheduled for glaucoma surgery. Forty patients were randomized to undergo either a nonpenetrating DS with MMC (DSMMC) (19 eyes) or a TP with MMC (TPMMC) (21 eyes). Postoperative examinations were performed at the 1st day, the 1st, 2nd and 3rd weeks and the 1st, 3rd, 6th, 9th and 12th months. Postoperative complications, number of antiglaucoma medications and the IOP level were checked at each control. Complete success (without antiglaucoma medications) and qualified success (with or without medications) were assessed at two target IOP levels, namely ≤21 and ≤17 mm Hg in both groups. Moreover, the success rates at ≤21 mm Hg target IOP level were compared with those from previous series of patients who had undergone DS without MMC (historical control group). Results: Data from all eyes were available until the 12th month. The mean preoperative IOP ± SD was 29.6 ± 5.8 mm Hg in DSMMC eyes, 28.0 ± 6.0 in TPMMC eyes; the mean IOP at the 1st postoperative day was 12.5 ± 4.2 and 13.9 ± 6.5 mm Hg, while at the endpoint the mean IOP was 14.5 ± 4.0 and 16.1 ± 3.8, respectively, with significant reduction (p < 0.0005) of the preoperative IOP in both groups. Complete success (≤21 mm Hg target IOP) in 15 eyes (78.9%) of the DSMMC group and in 15 eyes (71.4%) of the TPMMC group was respectively found, while qualified success was achieved in all the eyes. When a ≤17 mm Hg target IOP was considered, complete success in 12 eyes (63.1%) and 13 eyes (61.9%), and qualified success in 13 eyes (68.4%) and 15 eyes (71.4%) were found in the DSMMC and TPMMC groups, respectively. No significant intergroup differences were found in terms of success rate. There is no statistical significance in the Kaplan-Meier cumulative survival curves as for complete and qualified success rate in both surgical groups for a ≤17 mm Hg target IOP (log rank, p = 0.918 and p = 0.429, respectively). As for the frequency of postoperative complications, hypotony and shallow anterior chamber were significantly more frequent in TPMMC when compared with the DSMMC group. The historical comparison between the DSMMC group and simple DS cases shows no significant difference between the groups, with a mild positive trend in DSMMC when compared with DS eyes. Conclusions: Both techniques, DSMMC and TPMMC, control IOP efficaciously at our endpoint. Our results indicate that low-dosage MMC can be considered a mild enhancement of DS IOP lowering effect without any negative effect on the well-known intra- and postoperative safety of the technique.

Biodegradable collagen matrix implant vs mitomycin-C as an adjuvant in trabeculectomy: a 24-month, randomized clinical trial

“…The low complication rate with low-dosage MMC in our sample is in agreement with our previous studies. 8,24,35,36 A recent pilot study 20 is not in agreement with our results, since it showed OLO to have a larger amount of complications than simple trabeculectomy. The conjunctival closure with two simple 10-0 nylon sutures at the flap extremities was probably responsible for a higher incidence of positive Seidel test with flat anterior chamber in the study group, and could have reduced the beneficial effect of the implant in bleb development.…”

“…22,23 When MMC was the randomized adjunctive therapy (Kyowa S.r.l., Milan, Italy), a Weck-cell sponge was cut into two to three pieces, B4 mm  2 mm  0.5 mm, soaked with MMC at a concentration of 0.2 mg/ml and placed under the dissected conjunctiva surrounding the scleral flap 22,23 and on the scleral bed. 24 The sponges were left in position for 2 min in order to maintain contact with the Tenon's capsule side of conjunctiva. Thereafter, the eye was irrigated with 15 ml of balanced salt solution.…”

E-PTFE (Gore-Tex®) implant with or without low-dosage mitomycin-C as an adjuvant in penetrating glaucoma surgery: 2 year randomized clinical trial

“…Evidence-based data indicate that the use of mytomicin-C (MMC) during trabeculectomy has a significant positive effect on postoperative intraocular pressure (IOP) (Jampel et al 2002;Wilkins et al 2005). In our experience, MMC can be regarded as an enhancement of the deep sclerectomy IOP-lowering effect without evidence of antimetabolite-related complications (Cillino et al 2005). On the other hand, MMC-augmented glaucoma surgery can be associated with a significantly higher frequency of late bleb leaks (Anand & Atherley 2005;Anand et al 2006).…”

“…When an ePTFE membrane implant was scheduled, two intrascleral pockets were dissected with a bevel-up crescent knife, continuing the scleral bed under the flap at its two vertical edges, with an extension of at least 0.5 mm. When MMC use was scheduled, a fluidretaining sponge (such as a Weck-cell sponge), fashioned to be approximately 7 · 3 mm in length and width and about 0.5 mm in depth, was soaked with MMC in a concentration of 0.2 mg ⁄ ml and placed on the scleral bed under the scleral flap, as described in a previous study (Cillino et al 2005). The sponge was left in position for 2 min, with the conjunctival flap pulled over the scleral flap in order to make the Tenon's-capsule side of the conjunctiva get in contact with the MMC.…”

Outcomes of combined phacoemulsification and deep sclerectomy: a 10-year UK single-centre study

“…32,33 There is also evidence for a similar role of MMC in primary DS. [34][35][36][37][38][39] The decision to use MMC during individual surgical cases was difficult to pinpoint from our database. Patients in the MMC group were slightly younger and probably had worse visual field (VF) mean deviation.…”