[Follow-up of a pilot study of trabeculectomy with low dosage mitomycin C (0.2 mg/ml for 1 minute). Independent evaluation of a retrospective nonrandomized study]

Cross-linked hyaluronic acid viscoelastic scleral implant in trabeculectomy

Purpose:

Patients with glaucoma undergoing trabeculectomy develop bleb cicatrix causing poor postoperative intraocular pressure (IOP) control and low success rates. Several approaches have been explored over the years for better outcomes. This study assesses the safety, efficacy, and outcome of trabeculectomy with HealaFlow^® (Anteis S. A, Geneva, Switzerland), a high-molecular-weight cross-linked hyaluronic acid viscoelastic gel, and comparing it with the antimetabolite Mitomycin-C (MMC).

Methods:

A prospective, interventional, case-controlled study conducted at a tertiary care hospital in Southern India on 60 eyes of patients requiring trabeculectomy divided in two groups – HealaFlow scleral implant and adjuvant low-dose MMC (0.1 mg/mL). Postoperative IOP reduction along with bleb morphology was assessed over follow-up at 1 week, 1 month, 3 months, 6 months, and 12 months.

Results:

Preoperatively IOP in the two groups was statistically similar. Postoperative IOP on day 1 had statistically significant reduction in both groups with greater reduction in MMC group. However, by 12 months, the IOP reduction was statistically similar in both groups, i.e., 46.24% (to 11.04 ± 2.55 mmHg) and 54.47% (to 11.99 ± 3.37 mmHg) in HealaFlow^® group and MMC group, respectively (P > 0.05). The bleb morphologies were similar and complications were seen equally, which resolved by 4 weeks. A complete success rate of 89.29% and a qualified success rate of 10.71% were observed equally in both groups.

Conclusion:

Absorbable biosynthetic cross-linked hyaluronic acid and low-dose MMC are equally safe and efficacious in trabeculectomy with significant IOP reduction and good bleb morphology. Therefore, it is a novel substitute for MMC.

Stab incision mitomycin C-assisted rapid trabeculectomy: A 'SMART' trabeculectomy alternative

The aim of the present study was to introduce a new modified trabeculectomy technique, stab incision mitomycin C (MMC)-assisted rapid trabeculectomy (SMART), which requires less surgical time and tissue manipulation. A total of 41 eyes with indication for trabeculectomy underwent glaucoma surgery with the SMART technique; superior subconjunctival injection of 0.005 mg MMC mixed with 0.1 ml lidocaine, followed by small, fornix base conjunctival opening. A stab incision was made to enter the anterior chamber 1.5 mm post-limbus using a 2.4 mm cataract knife. Double 0.75 mm punch and peripheral iridectomy were performed. A releasable suture was placed in the scleral opening, and matrix sutures to close conjunctiva. The preoperative mean intraocular pressure (IOP) was 23.8 mmHg, with a mean number of medications of 3.3. The mean follow-up duration was 27.6 months, with a range of 12-46 months. A year post-surgery, the mean IOP was 11 mmHg, with a mean number of medications of 0.7, corresponding to a reduction of 12.8 mmHg in IOP and 2.6 in the number of medications. During follow-up, additional 5-fluorouracil injections were administered when needed. In conclusion, SMART with wound modulation appears to be a safe and quick alternative to classic trabeculectomy. Few minor and no major complications were observed during the first 2.5 years of follow-up, with all eyes maintaining an IOP <15 mmHg.

Evaluating the efficacy of short duration Mitomycin C in safe surgery system trabeculectomy combined with cataract surgery

Purpose: To compare the efficacy of 0.2 mg/ml Mitomycin C (MMC) applied for 1-minute versus 2-minutes in patients undergoing combined surgery for primary glaucoma coexistent with cataract.

Materials and methods: This was a randomized controlled clinical trial of 63 patients operated on for primary glaucoma (POAG or PACG) with visually significant cataract. All patients underwent safe surgery system trabeculectomy with manual small incision cataract surgery (MSIC) and implantation of PC IOL. Patients were randomized into intra-operative MMC 0.2 mg/ml for 1-minute (study group) and MMC 0.2 mg/ml for 2-minutes (control group). Success was measured on the basis of two different intraocular pressure (IOP) goals (IOP ≤21 mmHg, IOP ≤18 mmHg) and mean IOP reduction from baseline at the end of 12 months.

Results: At 12 months, significant decreases in mean IOP were observed in both groups (P<0.001).The mean IOP reduction was 31.33±9.06% in the study group, as compared to 43.32±9.38% in the control group (P<0.001). The overall success for IOP ≤21 mm Hg was 80.5% in the study group and 90.9% in the control group (P<0.05). Kaplan-Meier analysis showed an insignificant difference in overall success rates of the two groups.

Conclusion: The IOP reduction with 2-minute MMC (0.2 mg/ml) is more effective than 1-minute MMC after 12 months. It offers a decrease in anti-glaucoma medications and substantial visual recovery in combined surgery done for primary glaucoma coexistent with cataract.

Stab Incision Glaucoma Surgery: A Modified Guarded Filtration Procedure for Primary Open Angle Glaucoma

Purpose. To describe a modified guarded filtration surgery, stab incision glaucoma surgery (SIGS), for primary open angle glaucoma (POAG). Methods. This prospective, interventional case series included patients with POAG (IOP ≥21 mmHg with glaucomatous visual field defects). After sliding superior conjunctiva down over limbus, 2.8 mm bevel-up keratome was used to create conjunctival entry and superficial corneoscleral tunnel in a single step starting 1.5 mm behind limbus. Lamellar corneoscleral tunnel was carefully dissected 0.5–1 mm into cornea and anterior chamber (AC) was entered. Kelly Descemet's punch (1 mm) was slid along the tunnel into AC to punch internal lip of the tunnel, thereby compromising it. Patency of ostium was assessed by injecting fluid in AC and visualizing leakage from tunnel. Conjunctival incision alone was sutured. Results. Mean preoperative IOP was 27.41 ± 5.54 mmHg and mean postoperative IOP was 16.47 ± 4.81 mmHg (n = 17). Mean reduction in IOP was 38.81 ± 16.55%. There was significant reduction of IOP (p < 0.000). 64.7% had IOP at final follow-up of <18 mmHg without medication and 82.35% had IOP <18 mmHg with ≤2 medications. No sight threatening complications were encountered. Conclusion. Satisfactory IOP control was noted after SIGS in interim follow-up (14.18 ± 1.88 months).

A review of the efficacy of mitomycin C in glaucoma filtration surgery

The success of trabeculectomy, which is considered the gold standard in the surgical treatment of glaucoma, depends on the wound healing response. The introduction of antiproliferative agents such as mitomycin C (MMC) has increased the success rates of trabeculectomy. However, complications due to these agents can be challenging to manage. Hence, it is important to determine the most efficacious dose and duration of exposure. Multiple studies suggest that many factors, including but not limited to MMC preparation, different concentrations, different exposure times, and method of application may affect success rate, and these factors were reviewed in this article. We concluded that lower concentrations of MMC that are prepared and applied in a standardized fashion, such as that using the Mitosol(®) kit (for 2-3 minutes) during trabeculectomy, could potentially provide trabeculectomy success rates similar to that reported with off-label preparations, and that such a treatment regime could result in in lower complication rates than higher doses of MMC.

Evaluating the long-term efficacy of short-duration 0.1 mg/ml and 0.2 mg/ml MMC in primary trabeculectomy for primary adult glaucoma

OBJECTIVE

To evaluate safety and efficacy of 0.1 mg/ml versus 0.2 mg/ml mitomycin-C (MMC), applied for 1 min subconjunctivally, during trabeculectomy for primary adult glaucoma in previously un-operated eyes.

MATERIALS AND METHODS

This is a randomised controlled, non-inferior, clinical trial consisting of 50 consecutive POAG or CPACG patients uncontrolled on maximal hypotensive therapy, meeting all inclusion criteria. Patients were randomized into two groups and underwent a standard limbus-based trabeculectomy with MMC: Group I, 0.1 mg/ml and Group II, 0.2 mg/ml. The pre-operative and post-operative intraocular pressure (IOP), bleb morphology, and visual acuity were recorded every 6 months for 2 years. Complete success (primary outcome) was defined as IOP ≤ 15 mmHg without any additional medications at the end of 2 years.

RESULTS

The average age of patients was 62.6 ± 9.8 years and 61.2 ± 8.1 years in Group 1 and 2, respectively; p = 0.57. The mean preoperative IOP was 22.5 ± 1.4 mmHg and 23.3 ± 1.8 mmHg; p = 0.10. The mean IOP at 2 years was 11.1 ± 1.6 mmHg and 10.8 ± 2.8 mmHg, a mean reduction in IOP of 50.6 ± 1.23 %, and 53.7 ± 2.25 % in Group I and II, respectively. The complete success was 92.0 % and 91.7 % in the two groups, respectively (p = 0.99), and there was one failure (Group II, post trauma). A wider bleb extent and larger areas of thin, transparent conjunctiva over the bleb were seen with the 0.2 mg/ml MMC group (p < 0.001) and in PACG eyes; p < 0.04.

CONCLUSION

A 1-min subconjunctival application of low dose 0.1 mg/ml MMC is non-inferior to 0.2 mg/ml and is probably a safer alternative, as thinning of the bleb is significantly less frequent in the long term.