Protocol for mitomycin C use in glaucoma surgery

Long-Term Surgical Outcomes and Possible Postoperative Complication with Severe Corneal Endothelial Cell Loss After Trabeculectomy for Cytomegalovirus-Associated Anterior Uveitis with Secondary Glaucoma

PURPOSE

We assess long-term surgical outcomes after an initial trabeculectomy for cytomegalovirus-associated anterior uveitis with secondary glaucoma (CMV-SG).

METHODS

We retrospectively reviewed the medical records of 16 eyes of 15 patients with CMV-SG and 157 eyes of 157 patients with primary open-angle glaucoma. The average follow-up period was approximately 3 years. Surgical success was defined as intraocular pressure (IOP) below 18 mmHg and at least 20% lower than baseline.

RESULTS

Kaplan-Meier survival analysis revealed that bleb survival rates were not significantly different in the CMV-SG and POAG groups (P = 0.75). Bullous keratopathy occurred in 2 of 16 eyes with CMV-SG postoperatively but did not occur in the POAG group. The corneal endothelial cell density decreased by 34.2 ± 22.7% in the CMV-SG group during an average follow-up period of 2.7 ± 2.0 years.

CONCLUSION

Trabeculectomy effectively controlled IOP in CMV-SG, but attention must be paid to corneal endothelial cell loss.

Comparison of the Efficacy and Safety of Trabeculectomy with Mitomycin C According to Concentration: A Prospective Randomized Clinical Trial

(1) Background: Mitomycin C (MMC) is commonly used during trabeculectomy. However, there is no consensus on which concentration should be used. We aimed to compare the efficacy and safety of 0.2 mg/mL and 0.4 mg/mL of MMC in eyes undergoing trabeculectomy. (2) Methods: Thirty-six eyes (36 glaucoma patients) were randomized to undergo a trabeculectomy with 0.2 mg/mL or 0.4 mg/mL of MMC. The success rate was evaluated according to three criteria: (A) intraocular pressure (IOP) ≤ 18 mmHg and IOP reduction ≥ 20%; (B) IOP ≤ 15 mmHg and IOP reduction ≥ 25%; (C) IOP ≤ 12 mmHg and IOP reduction ≥ 30%. Cox’s proportional hazard model was used to identify the predictive factors for failure. Immunohistochemical procedures for matrix metalloproteinase (MMP) were performed on Tenon’s tissue. Bleb morphology was evaluated. Safety was assessed based on the incidence of complications. (3) Results: Of the 36 eyes, 19 underwent trabeculectomy with 0.2 mg/mL of MMC and 17 with 0.4 mg/mL. The success rates were 75%, 67%, and 47% at 6 months for criteria A, B, and C, respectively. There were no significant differences between the two groups. High MMP-9 staining and low preoperative IOP were associated with failure (hazard ratio (HR), 5.556; p = 0.033, and HR, 0.936; p = 0.033). Complications included hypotony in two eyes (6%), hyphema in one eye (3%), and choroidal detachment in one eye (3%). (4) Conclusions: Trabeculectomy with 0.2 mg/mL and 0.4 mg/mL of MMC showed similar IOP-control effects to those recorded in previous studies, along with a low rate of complications. There was no significant difference in efficacy or safety between the 0.2 mg/mL and 0.4 mg/mL MMC groups.

Adjunctive Mitomycin C or Amniotic Membrane Transplantation for Ahmed Glaucoma Valve Implantation: A Randomized Clinical Trial

PURPOSE

To determine whether adjunctive mitomycin C (MMC) or amniotic membrane transplantation (AMT) improve the outcomes of Ahmed glaucoma valve (AGV) implantation.

METHODS

This double-blind, stratified, 3-armed randomized clinical trial includes 75 eyes of 75 patients aged 7 to 75 years with refractory glaucoma. Eligible subjects underwent stratified block randomization; eyes were first stratified to surgery in the superior or inferior quadrants based on feasibility; in each subgroup, eyes were randomly assigned to the study arms using random blocks: conventional AGV implantation (group A, 25 eyes), AGV with MMC (group B, 25 eyes), and AGV with AMT (group C, 25 eyes).

RESULTS

The 3 study groups were comparable regarding baseline characteristics and mean follow-up (P=0.288). A total of 68 patients including 23 eyes in group A, 25 eyes in group B, and 20 eyes group C completed the follow-up period and were analyzed. Intraocular pressure was lower in the MMC group only 3 weeks postoperatively (P=0.04) but comparable at other time intervals. Overall success rate was comparable in the 3 groups at 12 months (P=0.217). The number of eyes requiring medications (P=0.30), time to initiation of medications (P=0.13), and number of medications (P=0.22) were comparable. Hypertensive phase was slightly but insignificantly more common with standard surgery (82%) as compared with MMC-augmented (60%) and AMT-augmented (70%) procedures (P=0.23). Complications were comparable over 1 year (P=0.28).

CONCLUSIONS

Although adjunctive MMC and AMT were safe during AGV implantation, they did not influence success rates or intraocular pressure outcomes. Complications, including hypertensive phase, were also comparable.

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.

Long-Term Outcomes Following Trabeculectomy Combined with 25-Gauge Transconjunctival Sutureless Vitrectomy in Uveitis Patients

PURPOSE

To evaluate the efficacy of combined trabeculectomy (TLE) and 25-gauge transconjunctival sutureless vitrectomy (TSV-25) for uveitis patients.

METHODS

Combined TSV-25/TLE was performed in 9 eyes of 6 patients with vitreoretinal complications and intractable glaucoma. Visual acuity, intraocular pressure (IOP), inflammatory control, and number of hypotensive medications were evaluated.

RESULTS

Visual acuity improved in 7 of 9 eyes and inflammation was controlled with a decreased oral anti-inflammatory agent dosage in all eyes. Mean IOP, which was 28.11 ± 4.83 mmHg preoperatively, was significantly reduced (15.77 ± 2.68 mmHg) 5 years after surgery (p = 0.008). The mean number of IOP-lowering medications was 3.33 ± 0.71 before surgery and 1.11 ± 0.92 5 years after surgery (p = 0.007). Two eyes required implant of an Ahmed drainage valve during the follow-up period.

CONCLUSION

Combined TSV-25/TLE can be effective in managing vitreoretinal complications and elevated IOP in uveitis patients.

Large-area versus small-area application of mitomycin C during trabeculectomy

PURPOSE

To compare 2 different application methods of mitomycin C (MMC) in patients undergoing trabeculectomy.


METHODS

This retrospective trial compared outcomes of 191 eyes that underwent trabeculectomy with small-area (96 eyes; 50.3%) and large-area (95 eyes; 49.7%) MMC application. Main outcome measures were changes in intraocular pressure (IOP), required glaucoma medications, the frequency of complications, and postsurgical interventions.


RESULTS

Within both treatment groups, a highly significant IOP reduction was seen during follow-up (p < 0.0001). Statistical analyses revealed a significant difference in IOP between both groups. Patients treated with a larger size of surface area had a higher IOP reduction within the first postoperative year. Choroidal detachment, shallow anterior chamber, and bleb leak were seen more often in the large-area group with more aggressive MMC use. In contrast, complications associated with bleb failure such as bleb scarring were higher in the small-area group. Success rate was higher in the large-area MMC application group after 12 months.


CONCLUSIONS

Large-area treatment seems to be a more efficient application method of MMC during trabeculectomy.

Trabeculectomy with double low dose of mitomycin C - two years of follow-up

Purpose

To evaluate the efficacy and the safety of a surgical technique in which classic trabeculectomy ab externo is performed with a double application of low-dose mitomycin C (MMC) in uncontrolled open-angle glaucoma (OAG) patients.

Method

A consecutive series of 43 white patients (43 eyes) with uncontrolled primary OAG underwent trabeculectomy surgery. A double application of MMC (0.1%) was performed: the first under the Tenon’s capsule for 3 minutes, and the second below the scleral flap for 1 or 2 minutes, according to the risk factors. Complete success was defined as intraocular pressure (IOP) <14 mmHg without any additional glaucoma surgery or medication. Qualified success was defined as IOP <14 mmHg with additional needling revision.

Results

Mean preoperative IOP was 29.9 mmHg (SD 3.8) for all eyes evaluated. At 1 day postoperative, mean IOP was 6.7 mmHg (SD 1.26). At the end of the first 2 weeks postoperative, mean IOP was 8.6 mmHg (SD 1.7), at 12 months mean IOP was 11.3 mmHg (SD 1.4; P < 0.0001) and at 24 months mean IOP was 11.4 mmHg (SD 1.5; P < 0.0001). At 3 months, two eyes (5.4%) underwent needling of the bleb for cystic blebs formation.

Conclusion

In this study we presented the results after 2 years of follow-up of OAG undergoing trabeculectomy with dual administration of MMC (0.1 mg/mL). After 24 months, complete success was achieved in 93% of patients and a qualified success in 100% of patients.

Primary trabeculectomy with mitomycin C: safety and efficacy at 2 years

PURPOSE

To examine the rates of intermediate-term intraocular pressure (IOP) control after trabeculectomy with adjunctive mitomycin C (MMC) and assess for associated complications.

METHODS

Medical records of patients undergoing primary trabeculectomy with MMC at Concord Repatriation Hospital, Sydney between January 1997 and December 2005 were reviewed. All eyes with a minimum of 2-year follow up were included. Follow-up data were collected in a standardized form on postoperative IOP, bleb-related and other complications. Success was measured as IOP ≤ 18 mmHg and ≥ 6 mmHg (criteria 1) with (qualified success) or without (absolute success) the use of glaucoma medications. A secondary outcome measure was an IOP reduction of greater than 20% from baseline (criteria 2). Eyes with preoperative IOP of 18 mmHg or less were included, but also analysed separately to those eyes with preoperative IOP above 18 mmHg.

RESULTS

Sixty eyes from 42 patients were included in the study, with 3-year follow up on 48 eyes. Mean preoperative IOP was 25.3 mmHg (range 8-45) and mean postoperative IOP was 14.0 mmHg at 1- and 2-year follow up, and 14.7 mmHg at 3 years (ranges: 3-31, 4-30 and 8-45 mmHg respectively). Cumulative success for criteria 1 was 85.0% at 2 years and 83.3% at 3 years, and for criteria 2 it was 80.0% and 79.2%, respectively. The number of eyes on glaucoma medications was reduced from 51 preoperatively to 30 at 3 years. Complications were infrequent. There was one eye with a shallow anterior chamber beyond the immediate postoperative period. One eye required cataract surgery at 1-year follow up. Subgroup analysis was performed using the first operated eye only, and results did not differ significantly from overall results.

CONCLUSION

MMC-augmented trabeculectomy can significantly reduce IOP in the short and intermediate term, with a favourable safety profile.

Changes in the intraocular pressure of fellow untreated eyes following uncomplicated trabeculectomy

BACKGROUND AND OBJECTIVE

Previous studies have reported changes in the intraocular pressure (IOP) of fellow eyes following unilateral trabeculectomy or selective laser trabeculoplasty. This study evaluates changes in the IOP of fellow eyes following unilateral trabeculectomy and examines correlations of findings with clinical information.

PATIENTS AND METHODS

Sixty-one patients who underwent unilateral uncomplicated trabeculectomy were included. The IOP of both eyes was recorded on postoperative days 2, 3, 4, 15, 30, 60, and 90. Differences between preoperative and postoperative IOP in both eyes and correlations with clinical parameters were examined.

RESULTS

The IOP of the fellow eyes was significantly reduced on the fourth postoperative day. This reduction was significantly correlated (inversely) with central corneal thickness of fellow eyes and with the level of IOP reduction to the operated eyes.

CONCLUSION

The IOP of the fellow eyes remains largely unchanged during the first 3 months following trabeculectomy. However, a significant short-term reduction is noted on the fourth day, implying that unknown (possibly neurocrine) mechanisms may participate in the regulation of the IOP of fellow eyes.

Surgical outcomes of uveitic glaucoma

PURPOSE

Secondary glaucoma is a difficult and frequent complication of uveitis. The aim of this study is to describe the results of surgery in uveitic glaucoma and to identify situations linked to a high risk of failure of the surgery.

METHODS

Retrospective observational study. Clinical and surgical data from 27 cases of uveitic glaucoma that underwent glaucoma surgery over a period of 9 years were collected.

RESULTS

The main diagnosis and aetiology were anterior uveitis (61.90%) and herpes (38.10%) respectively. Trabeculectomy with mitomycin C was performed in 51.9% of the cases. An intraocular pressure lower than 16 mmHg and managed with less than two drugs was achieved in 48.15% of the cases. Higher risks of surgical failure were associated with intermediate uveitis, idiopathic uveitis, Fuchs' cyclitis, combined surgery with phacoemulsification, omission of mitomycin C, intraocular inflammation at surgery and relapse of the uveitis.

CONCLUSIONS

There are some situations linked to a high risk of failure of surgery in uveitic glaucoma, which should be avoided when possible, mainly the association of higher risk with combined approaches.

Differences between Goldmann Applanation Tonometry and Dynamic Contour Tonometry following Trabeculectomy

Background. To evaluate differences between Goldmann Applanation Tonometry (GAT) and Dynamic Controur Tonometry (DCT) following trabeculectomy. Methods. Thirty eight glaucomatous eyes with a history of trabeculectomy (Trabeculectomy group, TG), 20 eyes without a history of trabeculectomy but with a history of latanoprost use (Latanoprost group, LG), and 19 nonglaucomatous eyes (Control group, CG) were included. GAT-IOP, DCT-IOP, the difference between them (dIOP), the central corneal thickness (CCT), the axial length (AL), and the depth of the anterior chamber (ACD) were measured. Results. dIOP was significantly higher in TG (5.19 mmHg) than in LG (4.01 mmHg) and CG (1.98 mmHg). Correlations between AL and dIOP were statistically significant in both TG and LG but not in CG whereas correlations between dIOP and other clinical parameters examined were statistically not significant in all groups. Conclusions. The significantly higher dIOP in TG implies that the bio-mechanical properties of the ocular walls are altered following trabeculectomy.

Early-onset scleral and corneal ectasias following low-dose mitomycin-C-augmented trabeculectomy in a uveitic glaucoma patient

A case of early-onset sclerolimbal ectasia following low-dose topical mitomycin C application during uveitic glaucoma surgery is reported. Intraoperative and postoperative clinical courses were consistent with sclerolimbal ectasia. Adjunctive utilization of intraoperative low-dose 0.02% mitomycin C for the management of chronic uveitic glaucoma patients who are under concomitant systemic immunosuppressive regimen may enhance the risk of subacute postoperative sclerolimbal ectasia. Mitomycin C concentrations < 0.02%, decreased scleral exposure time, and a strict informed consent policy are strongly recommended in this subset of uveitic patients.