Intraoperative Injection vs Sponge-applied Mitomycin C during Trabeculectomy: One-year Study

γ-Cyclodextrin hydrogel for the sustained release of josamycin for potential ocular application

Glaucoma is the leading cause of blindness worldwide. However, its surgical treatment, in particular via trabeculectomy, can be complicated by fibrosis. In current clinical practice, application of the drug, Mitomycin C, prevents or delays fibrosis, but can lead to additional side effects, such as bleb leakage and hypotony. Previous in silico drug screening and in vitro testing has identified the known antibiotic, josamycin, as a possible alternative antifibrotic medication with potentially fewer side effects. However, a suitable ocular delivery mechanism for the hydrophobic drug to the surgical site does not yet exist. Therefore, the focus of this paper is the development of an implantable drug delivery system for sustained delivery of josamycin after glaucoma surgery based on crosslinked γ-cyclodextrin. γ-Cyclodextrin is a commonly used solubilizer which was shown to complex with josamycin, drastically increasing the drug's solubility in aqueous solutions. A simple γ-cyclodextrin crosslinking method produced biocompatible hydrogels well-suited for implantation. The crosslinked γ - cyclodextrin retained the ability to form complexes with josamycin, resulting in a 4-fold higher drug loading efficiency when compared to linear dextran hydrogels, and prolonged drug release over 4 days.

"Long-term safety and efficacy of injection mitomycin C(MMC) versus sponge application in trabeculectomies"

AIMS

To compare the long-term safety and efficacy of subconjunctival injection mitomycin C(MMC) with conventional sponge applied MMC during trabeculectomy.

METHODS AND MATERIAL

Retrospective analysis of 98 eyes of 90 patients who underwent trabeculectomy with Mitomycin C were divided into two groups, group 1- sponge (n = 52) and group 2- Injection(n = 46). Follow-up data were collected on day one, day 15, one month, three months, six months, one year, two years and three years. Data from baseline and follow-up visits were analyzed and compared to study the significant difference in intraocular pressure (IOP), number of antiglaucoma medications (AGM) and best corrected visual acuity (BCVA) . P-value of <0.05 was considered statistically significant.

RESULTS

Mean preop IOP was 34.61 ± 13.3 mmHg in group one and 33.07 ± 9.6 mmHg in group two, which reduced to 11.43 ± 3.2 and 11.59 ± 3.2 mmHg at three years (p < 0.001 in both groups) with no significant difference between the groups. Mean number of preoperative AGM was 2.28 ± 0.8 and 2.42 ± 0.7 in group one and two respectively which reduced to 1.19 ± 1.1(p = 0.405) and 0.88 ± 0.9(p = 0.001) at three years. Complete and overall success rates (complete + qualified) were 59.3% and 78.9% in group one and 60.9% and 80.4% in group two at three years. No statistically significant difference was found in complication rates, post-operative interventions, and final visual outcome in both groups.

CONCLUSIONS

Subconjunctival Injection MMC was a safe and effective alternative to sponge application with comparable long term surgical outcomes.

Short-term outcomes of Mitomycin-C augmented phaco-trabeculectomy using subconjunctival injections versus soaked sponges: a randomized controlled trial

OBJECTIVES

To determine whether subconjunctival Mitomycin-C (MMC) injections are as safe and effective as sponge-soaked MMC in phaco-trabeculectomy.

METHODS

This prospective, randomized, interventional study was conducted on consecutive patients with visually significant cataract and an uncontrolled primary open-angle glaucoma. One hundred thirty-nine patients were recruited but 15 were ineligible for analysis. The patients were randomized into a sponge/injection group. All participants received a twin-site phaco-trabeculectomy. They were followed up on days 1, 15, 30, 3 months and 6 months post-operatively. A p-value < 0.05 was considered significant.

INTERVENTIONS

Participants in the sponge group received an augmentation of their phaco-trabeculectomy with sponges soaked in a mixture of 0.04% MMC and 2% preservative-free Lignocaine in a 1:1 ratio, placed in the subconjunctival space for four minutes. Participants in the injection group received the same mixture as a subconjunctival injection, after surgical draping.

RESULTS

There were 62 patients in each group. The groups had no significant differences in their baseline characteristics. The mean IOP at 6 months was significantly lower in the injection group (14.8 ± 3.7 mm Hg) than in the sponge group (17.1 ± 6.4 mm Hg) (p = 0.02). There was no notable difference in the complications or the final post-operative visual outcome but a significantly greater number of patients in the sponge arm required removal of the releasable suture (p = 0.001) and additional anti-glaucoma medications (p = 0.04) at six months post-operatively.

CONCLUSIONS

Subconjunctival MMC achieves a lower IOP with fewer anti-glaucoma medications than sponge-soaked MMC at six months for twin-site phaco-trabeculectomy in primary open-angle glaucoma with no additional risks.

Long-term outcomes of Mitomycin-C augmented trabeculectomy using subconjunctival injections versus soaked sponges: a randomised controlled trial

PURPOSE

To compare the safety and efficacy of subconjunctival injection of Mitomycin C(MMC) with sponge-applied MMC during trabeculectomy.

METHODS

This prospective, randomised, interventional study was conducted on consecutive patients with uncontrolled glaucoma. 137 patients were randomised into an Injection group (Group 1, n = 66) and a sponge group (Group 2, n = 71). Trabeculectomy was performed in all patients who were followed up on days 1, 15, 30, 3 months, 6 months, 1 year, 2 years & 3 years postoperatively. Baseline & follow-up visits were compared to find out difference in the number of antiglaucoma medications (AGM), Intraocular pressure (IOP), and Best Corrected Visual Acuity (BCVA). In Group 1, the surgeon used MMC 0.2 mg/ml as subconjunctival injection and two separate semicircular surgical sponges soaked with MMC solution of 0.2 mg/mL were inserted subconjunctivally in Group 2.

RESULTS

Mean preop IOP was 34.21 ± 13.3 mmHg & 34.17 ± 10.6 mmHg in group 1 & 2 respectively, which reduced to 11.34 ± 3.7& 12.57 ± 4.7 mmHg(6 months),11.97 ± 4.2 & 13.60 ± 5.3 mmHg(1 year),12.42 ± 4.4 & 11.77 ± 2.8 mmHg (2 years) &11.25 ± 3.2 & 11.81 ± 3.2 mmHg at final visit(P < 0.001 in both groups)with no significant difference between the groups. The mean number of preoperative AGM was 2.32 ± 0.7 & 2.32 ± 0.8 in group1 & 2 respectively which reduced to 0.78 ± 0.9 (P < 0.001) & 1.13 ± 1.1(P = 0.930) at 3 years. Overall success rates were 75.3% in group 1 and 70.7% in group 2 at 3 years(p = 0.512). Postoperative complications and the final post-operative visual outcomes were similar between the groups.

CONCLUSION

Subconjunctival Injection of MMC is as safe and effective as sponge application with comparable surgical outcomes and complications in the long term.

Wound modulation in glaucoma surgery: The role of anti-scarring agents

Filtration surgery is one of the most frequently performed surgeries in the management of glaucoma, and trabeculectomy is considered the gold standard surgical technique for the same. Though trabeculectomy has been reported to have an excellent initial success rate, about 30% of them fail in 3 years, and nearly 50% of them fail in 5 years. The most significant risk of failure still seems to be wound scarring, especially episcleral fibrosis, leading to bleb failure. As a result, it is essential to explore the role of anti-scarring agents, including mitomycin C, and 5-fluorouracil in wound modulation and improving the bleb survival rate. Since these agents are widely used in trabeculectomy, it is crucial to understand the various modes of application, advantages, and adverse effects of these agents. On an evidence-based approach, all these points have been highlighted in this review article. In addition, the newer agents available for wound modulation and their scope for practical application are discussed.

Comparison of the safety and efficacy of Mitomycin C 0.02% used intra-operatively by subconjunctival injection versus direct scleral application using sponges in phacotrabeculectomy: A prospective randomized controlled trial

PURPOSE

To compare the safety and efficacy of subconjunctival injection (MMC: 0.02%) to those with subconjunctival application of sponges soaked in Mitomycin C (MMC: 0.02%) intra-operatively in patients who underwent phacotrabeculectomy.

METHODS

A total of 68 patients undergoing phacotrabeculectomy were randomized into two groups; the sponge group received 0.02% MMC-soaked sponges (n = 38), and the injection group received subconjunctival injection of 0.02% MMC (n = 30). The primary outcome was post-operative mean intra-ocular pressure reduction (IOP). The secondary outcomes were bleb morphology using Indiana Bleb Appearance Grading Score (IBAGS) and anterior segment optical coherence tomography (AS-OCT), post-operative use of 5-fluorouracil, and complications rates. These were compared at 1 week and 1, 3, and 6 months post-operatively. Complete success was defined as ≥30% reduction in IOP without anti-glaucoma medications.

RESULTS

In sponge and injection groups, the mean pre-operative IOP was 29.1 ± 8.1 and 29.8 ± 8.8 mmHg, respectively. At 6 months, IOP in sponge and injection groups reduced by 52% (14 ± 3.6 mmHg, P < 0.001) and 50% (15.2 ± 4.1 mmHg, P < 0.001), respectively. Complete success was observed in 90.9% in the sponge group and 95.83% in the injection group. Both groups had diffuse, shallow, relatively avascular blebs at 6 months using IBAGS and AS-OCT. A few complications were seen in the sponge group during this period, which were not vision-threatening.

CONCLUSION

Subconjunctival MMC injection is an effective, safe, convenient, and time-saving alternative to sponge-soaked delivery of MMC in phacotrabeculectomy.

Two-stage intra-tenon injection versus sponge-applied mitomycin C-augmented trabeculectomy: a one-year study

PURPOSE

Mitomycin C (MMC) is normally used to avoid scar formation in trabeculectomy. There has been a shift from conventional delivery via soaked sponges to preoperative injection of MMC. This study aimed to compare the effectiveness of a modified two-stage low-dose intra-Tenon injection with soaked sponges of MMC for trabeculectomy over a 1-year follow-up period.

METHODS

This retrospective study enrolled patients with glaucoma undergoing modified trabeculectomy with a two-stage intra-Tenon injection (0.01%, 0.1 mL) or soaked sponges (0.02%) of MMC. In the former group, patients received intra-Tenon injection of MMC (the first stage) at least 4 h before trabeculectomy (the second stage). Patient characteristics, preoperative and postoperative intraocular pressure, antiglaucoma medication use, complications, and post-trabeculectomy surgical interventions were recorded during a 1-year follow-up period.

RESULTS

There were 36 and 35 eyes in the injection and sponge groups, respectively, in 58 patients. The injection group showed significantly lower intraocular pressure (p < 0.05) at every time point except on postoperative day 1 and week 1, fewer medications at the 1-year follow-up (p = 0.018), and a higher complete success rate (p = 0.011) than the sponge group. Both techniques showed a significant reduction in intraocular pressure and medication use at the 1-year follow-up. There were no significant differences in complications between both groups.

CONCLUSION

Our two-stage intra-Tenon MMC injection technique resulted in lower postoperative intraocular pressure, less antiglaucoma medication use, and fewer needling revisions compared to the sponge technique.

A 2-Year, Single-Center Study to Assess the Safety and Effectiveness of the MicroShunt in Primary Open-Angle Glaucoma

AIM

The aim of the study was to assess the effectiveness and safety of the MicroShunt (formerly known as the MIDI-Arrow or InnFocus MicroShunt®), an 8.5-mm-long, 70-μm lumen-controlled ab externo glaucoma filtration surgery device made from poly(styrene-block-isobutylene-block-styrene) (SIBS), in patients with primary open-angle glaucoma (POAG).

METHODS

A 2-year, single-center, single-surgeon, nonrandomized, adaptive feasibility clinical study (NCT01563237) was conducted in France from June 2011 to November 2016. Eligible patients were aged 18-85 years and had POAG inadequately controlled on maximum tolerated medical therapy with intraocular pressure (IOP) ≥18 and ≤40 mm Hg. The MicroShunt was implanted ab externo with adjunctive use of mitomycin C (0.2-0.4 mg/mL applied for 2-3 min), alone or in combination with cataract surgery. The primary effectiveness endpoints were the reduction in IOP relative to the preoperative value assessed at each postoperative visit and the measurement of success at years 1 and 2. The primary safety endpoint was the incidence of all procedure- and/or device-related adverse events (AEs) during the study. The secondary effectiveness endpoint was the mean number of glaucoma medications per patient, and the secondary safety endpoint was the incidence of glaucoma reoperation.

RESULTS

Sixty-one eyes from 61 patients underwent MicroShunt implantation. Mean IOP ± standard deviation (SD) was significantly reduced from 25.7 ± 6.1 mm Hg at baseline (N = 61) to 15.8 ± 4.7 mm Hg at year 1 (n = 58) and 16.5 ± 6.0 mm Hg at year 2 (n = 52) (both p < 0.001). Overall success rates for patients achieving IOP ≥6 mm Hg and <21 mm Hg at year 1 and year 2 were 80.3% and 75.4%, respectively. Mean ± SD number of glaucoma medications per patient decreased significantly from 2.9 ± 1.1 at baseline to 0.6 ± 1.0 at year 1 (n = 58) and 1.0 ± 1.3 at year 2 (n = 52) (both p < 0.001). The most common procedure- and/or device-related AEs were investigator-reported increased IOP and hyphema. Four patients required reoperation.

CONCLUSIONS

In this study, sustained reductions in mean IOP and number of glaucoma medications from baseline were observed up to 2 years post-surgery. No long-term, sight-threatening AEs were observed.

Comparison of Surgical Outcomes of Sponge Application versus Subconjunctival Injection of Mitomycin-C during Combined Phacoemulsification and Trabeculectomy Surgery in Asian Eyes

Purpose:

To compare the outcomes of combined phacoemulsification–trabeculectomy surgery with intraoperative sponge-applied versus subconjunctival injection of mitomycin-C (MMC) in Asian eyes.

Methods:

This was a retrospective review of 95 eyes that consecutively underwent combined phacoemulsification–trabeculectomy surgery in a tertiary eye center in Singapore from January 2013 to June 2014. Data collected included intraocular pressure (IOP), best corrected visual acuity, and number of glaucoma medications. Outcome measures included postoperative IOP and complications at various timepoints up to 12 months after surgery.

Results:

Twenty eyes (21.1%) received 0.2 mg/ml subconjunctival MMC injection (“Group 1”) and 75 (78.9%) received 0.4 mg/ml sponge-applied MMC (“Group 2”). There was no difference between groups in demographics, IOP, and number of glaucoma medications preoperatively. There was a reduction in IOP at postoperative month (POM) 1, 6, and 12 in both the groups (POM12: Group 1, −2.8 ± 5.36 mmHg, P < 0.001; Group 2, −5.8 ± 6.29 mmHg, P = 0.054). At POM1, Group 2 showed a trend toward greater IOP reduction (−5.89 ± 7.67 mmHg vs. −1.55 ± 5.68 mmHg, P = 0.061). However, at both POM6 and POM12, there was no statistically significant difference in IOP reduction between the two groups. At POM12, complete success, defined as achieving an IOP of between 6 and 15 mmHg without the use of antiglaucoma medications, was achieved in 11 (55%) eyes in Group 1 and 48 (64%) in Group 2 (P = 0.9). There was a lower rate of postoperative hypotony in the Group 1 (0%) compared to Group 2 (8%) (P = 0.34).

Conclusion:

Combined phacoemulsification–trabeculectomy with subconjunctival MMC injection has comparable outcomes to that with sponge-applied MMC, with a similar reduction in IOP at 1, 6, and 12 months postoperatively and a lower postoperative complication rate.

One-Year Randomized Comparison of Safety and Efficacy of Trabeculectomy with Mitomycin C Sub-Tenon Injection versus Mitomycin C-Infused Sponges

PURPOSE

To compare the safety and efficacy of sub-Tenon injection of mitomycin C (MMC) with application of MMC-infused sponges during trabeculectomy.

DESIGN

Single-center randomized clinical trial.

PARTICIPANTS

A total of 56 eyes of 49 patients with open-angle glaucoma were included in this clinical trial.

METHODS

In this single-center randomized clinical trial, 56 eyes of 49 patients underwent trabeculectomy with MMC for primary open-angle glaucoma. Patients were randomized into 2 groups. The injection group received a sub-Tenon injection of 0.15 ml of 0.01% MMC diluted with preservative free lidocaine 2% (n = 27). In the sponges group, sponges soaked in 0.02% MMC were applied under the Tenon's capsule and the scleral flap for 2 minutes (n = 29). Intraocular pressure, endothelial cell count, best-corrected visual acuity, and number of intraocular pressure (IOP)-lowering medications were assessed before surgery and 1 week; 1, 3, and 6 months; and 1 year after surgery. Complete success was defined as IOP of 14 mmHg or less without medication. Bleb morphologic features were assessed using the Indiana Bleb Appearance Grading Scale bleb grading system.

MAIN OUTCOME MEASURES

Intraocular pressure reduction was the primary outcome. Bleb morphologic features and endothelial cell counts (ECCs) were secondary outcomes.

RESULTS

Mean IOP in the sponges group decreased from 30.5 ± 7.4 mmHg at baseline to 12.6 ± 5.9 mmHg at 1 year (P < 0.001); in the injection group, IOP decreased from 29.3 ± 6.8 mmHg at baseline to 12.7 ± 4.3 mmHg at 1 year (P < 0.001). No difference in IOP between the 2 groups was noted at any visit (P < 0.001). Surgical success was 81.5% and 82.8% in the injection and sponges groups, respectively, at 1 year. Mean ECC values were unchanged from baseline to 1 year after surgery for both groups (P = 0.444). Complication rates were similar in the 2 groups. Bleb morphologic features showed differences in the appearance and grading of the blebs between the 2 groups at 1 year, showing larger extent, lower height, and less vascularization in the injection group.

CONCLUSIONS

Sub-Tenon injection of MMC during trabeculectomy seems to be as safe and as efficacious as conventional application of MMC with sponges at 1 year after surgery. Bleb morphologic features show notable differences that may suggest a better long-term outcome.

[Glaucoma surgery today]

BACKGROUND

The main goals of glaucoma treatment are to preserve the visual function and maintain as high a quality of life as possible at a cost acceptable to society. Therefore, it is crucial to carefully observe each individual patient in order to determine an individual and personalized treatment approach.

MATERIAL AND METHODS

This article summarizes the advantages and disadvantages of medicinal glaucoma treatment as well as traditional methods of glaucoma surgery, based on the current state of knowledge. The article explains the various mechanisms of action of new minimally invasive procedures, introduces the methods mostly commonly used in Germany and gives recommendations for preoperative care and postoperative follow-up.

RESULTS/CONCLUSION

In addition to the plethora of medicinal glaucoma treatments and classical surgical procedures, new minimally invasive treatment alternatives have become available in the past few years. The latter are an option for an earlier surgical intervention, especially in naïve or previously treated patients who appear to be unsuitable for medicinal treatment.

Neovascularization of angle following trabeculectomy augmented with mitomycin-C

The purpose of this study was to report a case of neovascularization of angle (NVA) following trabeculectomy with mitomycin-c (MMC) in a patient with primary open-angle glaucoma. This case report describes a 68-year-old woman who developed NVA and hyphema 2 weeks following an uneventful trabeculectomy with MMC. Trabeculectomy may be associated with serious and vision-threatening complications such as hypotony, suprachoroidal hemorrhage, endophthalmitis, and bleb-related complications. However, neovascularization of the anterior segment is not a commonly reported complication. Neovascularization of the anterior segment is a rare postoperative complication that usually occurs following strabismus or retinal detachment surgeries. The underlying ischemic trigger for anterior segment neovascularization is usually a posterior segment pathology or carotid artery insufficiency. These causative factors were excluded in our patient by lack of any abnormal finding in fundus fluorescein angiography and carotid Doppler ultrasonography. The patient received three subconjunctival bevacizumab injections (1.25 mg/0.1 ml) with frequent topical steroids and showed marked regression of the neovessels. The bleb was functional, and intraocular pressure remained at low teen afterward. NVA following trabeculectomy without any posterior segment or carotid pathologies responded well to subconjunctival bevacizumab and topical steroids.

National survey of intraoperative mitomycin C use during trabeculectomy surgery in the UK

PURPOSE

Mitomycin C is a routinely used antimetabolite which effectively limits the scarring process. Conventionally, the intra-operative technique of MMC delivery during trabeculectomy is the direct application of the soaked sponges. The aim of this study is to evaluate the current practice of delivering MMC during trabeculectomy and to see the practices related to a retained MMC swab during trabeculectomy in the UK.

METHODS

An electronic questionnaire of 8 questions regarding the intraoperative use of MMC during trabeculectomy surgery was emailed to 69 ophthalmologist members of the UK and Eire glaucoma society (UKEGS) through email in July 2019.

RESULTS

97.2% of the surveyed glaucoma surgeons said they use MMC during trabeculectomy routinely, while 2.9% said they never use MMC for trabeculectomy. In reply to a question 'Have you ever had a retained MMC-soaked sponge/fragment of sponge', 11.76% replied 'yes', 88.24% said 'No'. In response to what technique was employed at the time of retained MMC sponges, all the respondents said they had employed the same technique of 'multiple individual sponges'. 47.1% surgeons said they use multiple individual sponges on being asked what technique they currently employ for delivering MMC during trabeculectomy surgery, while 14.7% surgeons use multiple sponges linked with a 'necklace suture' and 5.9% inject MMC.

CONCLUSION

Our survey suggests the intra-operative MMC use in the UK is high and that unintentional MMC-soaked swab retention does occur, albeit rarely. A preference of using the MMC-soaked swabs as a delivery method of MMC is seen in our survey.

A Randomized Controlled Trial Comparing Subconjunctival Injection to Direct Scleral Application of Mitomycin C in Trabeculectomy

PURPOSE

To compare the efficacy of intraoperative scleral application with subconjunctival injection of mitomycin C (MMC) in trabeculectomy.

DESIGN

Prospective, randomized, interventional study.

METHODS

This study took place in a single clinical practice in an academic setting. Patients had medically uncontrolled glaucoma as indicated by high intraocular pressure (IOP), worsening visual field, or optic nerve head changes in whom primary trabeculectomy was indicated. Patients were older than 18 years with medically uncontrolled glaucoma and no history of incisional glaucoma surgery. Patients were randomized to MMC delivered by preoperative subconjunctival injection or by intraoperative direct scleral application using surgical sponges during trabeculectomy. Comprehensive eye examinations were conducted at 1 day, 1 week, 6 weeks, 3 months, and 6 months postoperatively. Subconjunctival 5-fluorouracil injections were given postoperatively, as needed. The primary outcome was the proportion of patients who demonstrated IOP of <21 mm Hg and ≥30% reduction in IOP from baseline. Secondary outcome measures included the number of IOP-lowering medications, bleb morphology using the Indiana Bleb Appearance Grading Scale, and complication rates.

RESULTS

Participants (n = 100) were randomized into groups matched for baseline demographics, glaucoma status, and baseline IOP. At 6 months, there were no significant differences between the injection (n = 38) and sponge (n = 40) groups in surgical success (P = .357), mean IOP (P = .707), number of glaucoma medications (P = 1.000), bleb height (P = .625), bleb extension (P = .216), bleb vascularity (P = .672), or complications rates.

CONCLUSION

Both techniques of MMC delivery (subconjunctival injection and direct scleral application) resulted in comparable surgical outcomes and bleb morphologies.

Effects of Lidocaine on Mitomycin C Cytotoxicity

PURPOSE

Intra-Tenon or subconjunctival injection of a solution of mitomycin C (MMC) and 1% preservative-free lidocaine (as an anesthetic) has gained popularity for its use in trabeculectomy, a filtering surgery for glaucoma. To our knowledge, no studies have analyzed the impact of lidocaine on the cytotoxic effects of MMC in this setting. This study was conducted to evaluate in vitro fibroblast cytotoxicity to a solution of MMC (0.2 mg/ml) and 1% preservative-free lidocaine.

DESIGN

Experimental study.

PARTICIPANTS

Nonhuman subject research.

METHODS

Cultured human conjunctival fibroblasts were incubated in phosphate-buffered saline (PBS) (control), MMC (0.2 mg/ml), a mixture of 0.2 mg/ml MMC + 1% preservative-free lidocaine, or 1% preservative-free lidocaine. Samples were taken at 2, 5, 10, 30, and 60 minutes, and a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay with photoabsorbance testing was used to assess conjunctival cell viability.

MAIN OUTCOME MEASURE

Mean photoabsorbance.

RESULTS

Mean photoabsorbance across all time intervals was 0.680 for solutions incubated in PBS, 0.642 for MMC, 0.612 for MMC + 1% preservative-free lidocaine, and 0.605 for 1% preservative-free lidocaine. A 2-way analysis of variance analyzing solution, time, and solution-time interaction on photoabsorbance showed that PBS was least cytotoxic and an optimal control for this study. Tukey post hoc comparisons showed that MMC was more cytotoxic than PBS (P < 0.001). However, both MMC + 1% preservative-free lidocaine and 1% preservative-free lidocaine were more cytotoxic than MMC and PBS (P < 0.01 for all). No significant differences in cytotoxicity comparing lidocaine-containing solutions were observed.

CONCLUSIONS

In this in vitro study, we found an increase in cytotoxicity when MMC (0.2 mg/ml) was combined with 1% preservative-free lidocaine. We note that lidocaine did not inhibit MMC cytotoxicity and exhibited a significant cytotoxic effect on its own.

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.

A Comparison of Trabeculectomy Surgery Outcomes With Mitomycin-C Applied by Intra-Tenon Injection Versus Sponge

PURPOSE

To compare the outcomes of mitomycin-C (MMC) delivered by intra-Tenon injection vs sponge application during trabeculectomy surgery.

METHODS

We retrospectively reviewed 566 patients with primary and secondary glaucoma diagnoses who received trabeculectomy surgery with MMC in an academic medical center. Exclusion criteria were age less than 18 years, no light perception vision, combined surgery, previous glaucoma incisional surgery, intraoperative 5-fluorouracil, or follow-up <1 month. Subjects were divided into 2 cohorts: MMC delivered by sponge application or by intra-Tenon injection. Main outcome measures were postoperative intraocular pressure (IOP) level and secondary measures were survival rate for IOP control, glaucoma medication use, complication rate, and vision.

RESULTS

After inclusion/exclusion criteria, 316 eyes were available for analysis; 131 eyes had MMC delivered via sponge and 185 eyes via injection. Mean postoperative IOP was not significantly different between treatment groups but change in IOP from baseline was lower in the sponge vs the injection group 24 months after surgery (P = .038). The MMC sponge group had significantly more tense, vascularized, or encapsulated blebs as a late complication (P = .046). Time to failure for postoperative IOP control was not significantly different between MMC treatment groups, but older patient age and limbus-based conjunctival incision were associated with significantly longer time to fail.

CONCLUSIONS

The application of MMC by injection was similar to application by sponge in lowering IOP in patients with glaucoma and the safety of both techniques appears to be comparable. Limbus-based conjunctival incision had longer time to failure for postoperative IOP control vs fornix-based incision. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Leftover mitomycin-c sponge causing blebitis

Trabeculectomy is the commonest surgical intervention performed worldwide for the treatment of open-angle glaucoma. However, the use of antimetabolites during trabeculectomy has been associated with various bleb related complications. We report this interesting case to highlight unique clinical presentation and management of a leftover mitomycin-C sponge causing blebitis.

pH of Mitomycin-C Formulations for Filtration Surgery

PRECIS

The use of mitomycin-C as a mixed formulation with lidocaine and epinephrine for filtration surgery may alter its pH and consequently affect clinical effectivity.

Two-year results of a multicenter study of the ab interno gelatin implant in medically uncontrolled primary open-angle glaucoma

PURPOSE

To evaluate the effectiveness of an ab interno subconjunctival gelatin implant as primary surgical intervention in reducing intraocular pressure (IOP) and IOP-lowering medication count in medically uncontrolled moderate primary open-angle glaucoma (POAG).

METHODS

In this prospective, non-randomized, open-label, multicenter, 2-year study, eyes with medicated baseline IOP 18-33 mmHg on 1-4 topical medications were implanted with (phaco + implant) or without (implant alone) phacoemulsification. Changes in mean IOP and medication count at months 12 (primary outcomes) and 24, clinical success rate (eyes [%] achieving ≥ 20% IOP reduction from baseline on the same or fewer medications without glaucoma-related secondary surgical intervention), intraoperative complications, and postoperative adverse events were assessed.

RESULTS

The modified intent-to-treat population included 202 eyes (of 218 implanted). Changes (standard deviation) in mean IOP and medication count from baseline were - 6.5 (5.3) mmHg and - 1.7 (1.3) at month 12 and - 6.2 (4.9) mmHg and - 1.5 (1.4) at month 24, respectively (all P < 0.001). Mean medicated baseline IOP was reduced from 21.4 (3.6) to 14.9 (4.5) mmHg at 12 months and 15.2 (4.2) mmHg at 24 months, with similar results in both treatment groups. The clinical success rate was 67.6% at 12 months and 65.8% at 24 months. Overall, 51.1 (12 months) and 44.7% (24 months) of eyes were medication-free. The implant safety profile compared favorably with that published for trabeculectomy and tube shunts.

CONCLUSIONS

The gelatin implant effectively reduced IOP and medication needs over 2 years in POAG uncontrolled medically, with an acceptable safety profile. ClinicalTrials.gov registration number: NCT02006693 (registered in the USA).

Fornix-Based Trabeculectomy Conjunctival Closure: Winged Sutures versus Modified Wise Closure

PURPOSE

To compare the midterm safety and efficacy profile of winged sutures versus modified Wise closure for fornix-based trabeculectomy.

DESIGN

Retrospective comparative study.

PARTICIPANTS

Consecutive cases that underwent fornix-based trabeculectomy by a single surgeon between January 5, 2015, and May 8, 2017.

METHODS

Potential cases were identified using the Current Procedural Terminology code, and their charts were reviewed thoroughly. Only 1 eye per patient was included. Demographic and clinical data were collected.

MAIN OUTCOME MEASURES

Primary outcomes were bleb leak and subsequent surgical revision rates. Secondary outcomes included intraocular pressure (IOP), number of glaucoma medications (NGM), visual acuity (VA), and other complications.

RESULTS

A total of 313 patients were identified, 157 with winged sutures and 156 with modified Wise closure. Baseline demographic and clinical characteristics were similar between the 2 groups. Twenty-six cases (16.6%) of winged sutures and 10 cases (6.4%) of modified Wise group developed bleb leak (P = 0.007), but only a total of 10 eyes needed bleb revision (P = 0.336). Other complications were similar in rates between the groups (P > 0.05). At 6 months, the modified Wise group had significantly greater IOP reduction (-3.10±1.29 [standard error], P = 0.016). Number of glaucoma medications reduction and VA evolution were similar between the 2 groups (P > 0.05).

CONCLUSIONS

Fornix-based trabeculectomy with either closure technique was effective in lowering IOP and NGM with comparable safety profile at 6 months. Furthermore, modified Wise closure provided larger IOP reduction and lower bleb leak rate, suggesting a potential superiority to winged sutures. Our study was limited by mitomycin C (MMC) delivery method change near the time of conjunctival closure change, although MMC delivery methods did not show significance in any outcome model.