Ocular concentrations of mitomycin C using different delivery devices

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.

Cellular toxicity profile of a new ophthalmic sponge

Introduction: Ophthalmic sponges are used for cleaning the eye surface and absorbing fluids during ophthalmic procedures. This study compared the biological safety and stability of a new ophthalmic sponge, Occucell® (OccuTech Inc, Seongnam, Korea), on the human conjunctival epithelial cells with those of preexisting products to evaluate its clinical application.Materials and Methods: The cytotoxicity of four products, Occucell, a new product, Ultracell®, Eyetec-1, and Eyetec-2, on conjunctival epithelial cells, was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) analysis. Additionally, human conjunctival epithelial cells were stained with a Live & Dead marker and observed using a fluorescence microscope. To evaluate the effect of the ophthalmic sponges on the secretion of IL-1β and TNF-α, cultured conjunctival epithelial cells were treated with 0.5% DMSO eluates of the ophthalmic sponges, and IL-1β and TNF-α mRNA levels were estimated using real-time polymerase chain reaction assays.Results: Cells treated with Occucell showed comparable viability to those treated with other preexisting products. Conjunctival epithelial cells showed more than 90% viability when treated with the ophthalmic sponge extracts, as determined by the MTT assay. No significant differences in the number of live & dead cells were observed between the control and treatment groups. Cells treated with all four ophthalmic sponge eluates showed similar IL-1β and TNF-α mRNA levels.Discussion: Occucell, an eye sponge used during ophthalmic surgery in clinical practice, did not affect the viability of conjunctival epithelial cells, and more than 90% of the cells were viable after the treatment. Further, Occucell showed similar effects on IL-1β and TNF-α secretion as that of other ophthalmic sponges used in the clinic. This suggested that Occucell is a safe product comparable to the preexisting products.

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.

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.

Learning from the past: Mitomycin C use in trabeculectomy and its application in bleb-forming minimally invasive glaucoma surgery

Trabeculectomy has been performed since the mid-1960s and remains the gold standard for glaucoma surgery. Newer surgical options have evolved, collectively referred to as minimally invasive glaucoma surgeries. Despite producing large intraocular pressure decreases, full-thickness procedures into the subconjunctival space may be limited by fibrosis. Mitomycin C (MMC) and 5-fluorouracil have been in use with trabeculectomy with good evidence of significantly increased success at the cost, however, of an increased risk of complications. Off-label MMC application can be found in almost all clinical trials, including in combination with minimally invasive glaucoma surgeries. We explore current evidence for MMC use in trabeculectomy and how this may differ for minimally invasive glaucoma surgery devices and analyze the range of agents and doses that are used. Although we found that most studies could not show any correlation between MMC dosage and the surgical outcome, the success rates with the Xen® microshunt seemed to be higher when using 20 mcg of MMC than when using 10 mcg. Certain important methodological considerations make this hard to confirm definitively, and other factors such as placement of the device may play a more substantial role. For the PreserFlo® microshunt, preliminary data suggest higher success rates with higher MMC dosage at the cost of higher device-related adverse events and reoperations. Although the ideal dose still needs to be established, it seems very likely that MMC provides significant improvement in outcomes in bleb-forming minimally invasive glaucoma procedures.

Intraoperative injection versus sponge-applied mitomycin C during trabeculectomy: One-year study

Purpose

To determine the safety and efficacy of mitomycin C (MMC) injection versus sponge during trabeculectomy.

Methods

It is a prospective analysis of patients who underwent trabeculectomy with MMC and followed up for 1 year, divided into two groups, namely, group 1- injection (n = 21), group 2-> sponge (n = 21). The same concentration of MMC was used for both groups. Inclusion criteria were trabeculectomies with MMC for intraocular pressure (IOP) control in eyes with glaucoma (primary + secondary) with a follow-up of 1 year.

Results

Mean preoperative IOP in group 1 was 29.00 ± 11.92 mmHg and group 2 was 25.87 ± 11.09 mmHg, which reduced to 12.19 ± 4.03 and 15.56 ± 10.72 mmHg at final visit with P value of 0.0002 and 0.001, respectively. Mean preoperative number of antiglaucoma medications was 2.4 ± 0.87 in group 1 and 2.3 ± 0.96 in group 2, which reduced to 0.38 ± 0.5 and 0.91 ± 0.85 with P value of 0.001 and 0.0003, respectively. The complete success rate was 52.4% in the injection group and 26.1% in the sponge group at end of 1 year. Overall, success rate (complete + qualified) was 90.5% and 87% in group 1 and group 2 at final visit. All major complications were encountered in sponge group. 1 (11.1%) patient developed choroidal detachment and one had malignant glaucoma which got resolved by medical management. 33.3% cases had encapsulated bleb which received bleb needling. 44.4% cases underwent Argon laser suture lysis postoperatively.

Conclusion

The MMC injection may be as safe and as effective as conventional sponge application with comparable estimated complete treatment success.

Ocular Biodistribution Studies using Molecular Imaging

Classical methodologies used in ocular pharmacokinetics studies have difficulties to obtain information about topical and intraocular distribution and clearance of drugs and formulations. This is associated with multiple factors related to ophthalmic physiology, as well as the complexity and invasiveness intrinsic to the sampling. Molecular imaging is a new diagnostic discipline for in vivo imaging, which is emerging and spreading rapidly. Recent developments in molecular imaging techniques, such as positron emission tomography (PET), single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI), allow obtaining reliable pharmacokinetic data, which can be translated into improving the permanence of the ophthalmic drugs in its action site, leading to dosage optimisation. They can be used to study either topical or intraocular administration. With these techniques it is possible to obtain real-time visualisation, localisation, characterisation and quantification of the compounds after their administration, all in a reliable, safe and non-invasive way. None of these novel techniques presents simultaneously high sensitivity and specificity, but it is possible to study biological procedures with the information provided when the techniques are combined. With the results obtained, it is possible to assume that molecular imaging techniques are postulated as a resource with great potential for the research and development of new drugs and ophthalmic delivery systems.

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

AIM

To determine the safety and efficacy of intraoperative injection of mitomycin C (MMC) against conventional sponge-applied MMC during trabeculectomy.

MATERIALS AND METHODS

This study was a retrospective, comparative case series. Thirty eyes with primary open-angle glaucoma underwent consecutive trabeculectomies with MMC injection (injection group), and thirty eyes with sponge-applied MMC were as controls (sponge group). Data were collected preoperatively and postoperatively at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year after surgery. Demographic data, applanation intraocular pressure (IOP), best-corrected visual acuity (VA), number of glaucoma medications, postoperative interventions, postoperative complications, and number of visits within 3 months were recorded. In order to stratify data, proportion of eyes achieving >30% IOP reduction from baseline with or without glaucoma medications was calculated and defined as surgical success.

RESULTS

Mean IOP reduction at 1 year was significant in both the injection and sponge groups from baseline (46.8 and 37.8% respectively). The injection group had overall lower postoperative IOP and comparable complete treatment success, defined as achieving >30% IOP reduction without glaucoma medications (p = 0.941). The number of postoperative visits within 3 months and the proportion of eyes needing 5-fluorouracil (5-FU) intervention were significantly lower in the injection group (p = 0.03, p = 0.04 respectively).

CONCLUSION

Injection of MMC was as safe and effective as sponge application with comparable estimated complete treatment success, less need for visits within 3 months, and 5-FU intervention.

CLINICAL SIGNIFICANCE

Surgeons may consider intraopera-tive injection of MMC in appropriate patient cohorts given comparable safety and efficacy and several advantages over traditional sponge application. Further study in a prospective, larger, long-term manner is necessary to assess this modality.How to cite this article: Khouri AS, Huang G, Huang LY. Intraoperative Injection vs Sponge-applied Mitomycin C during Trabeculectomy: One-year Study. J Curr Glaucoma Pract 2017;11(3):101-106.

Long-Term Subconjunctival Delivery of Brimonidine Tartrate for Glaucoma Treatment Using a Microspheres/Carrier System

Core-shell polymer microspheres with poly(d,l-lactic-co-glycolic acid) core and poly(l-lactic acid) (PLLA) shell are developed for the long-term subconjunctival release of brimonidine tartrate (BT) in order to reduce intraocular pressure (IOP) in the treatment of glaucoma. The PLLA-rich shell acts as a diffusion barrier, enabling linear release of BT over an extended period of 40 d. The microspheres are encased in a porous non-degradable methacrylate-based carrier for ease of subconjunctival implantation in a glaucoma-induced rabbit model. In vivo release of BT from the microspheres/carrier system has enabled a significant, immediate IOP reduction of 20 mmHg, which is sustained for 55 d. Long-term IOP reduction may be maintained by periodic replacement of the microspheres/carrier system.

MRI in ocular drug delivery

Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed.

[Dosage and kinetics of MMC release of a collagen implant used as a delivery device in glaucoma surgery in the rabbit eye]

PURPOSE

To determine the absorption and the release of mitomycin-C from a collagen implant and tissue impregnation in the anterior structures of the rabbit eye.

METHODS

Determining the quantity of mitomycin-C that a collagen implant can absorb with the difference between dry and soaked weight. Mitomycin-C release was measured in vitro using spectrophotometry. The measurement was repeated using a bioassay. Ocular tissue impregnation was determined in 12 eyes of six rabbits. Sclera, implant, aqueous, and ciliary body specimens were collected for concentration measurement using HPLC from 1 to 6 h after surgery.

RESULTS

The mean mitomycin-C quantity absorbed in the implant was 3.22+/-0.2 microg. In vitro release was 0.13 mg/ml after 10 min and 0.05 microg/ml at 6 h. The bioassay showed almost no antifibrotic activity in sclera. In vivo release of mitomycin-C was high from the first to the sixth hour.

CONCLUSION

After filtering surgery, mitomycin-C in the collagen implant is clearly released and ocular tissues are effectively impregnated.

Foreign body granulomas secondary to retained sponge fragment following mitomycin C trabeculectomy

BACKGROUND

Bleb related inflammation following trabeculectomy is usually seen in the late post operative period and is unusual in the first 6 months after surgery We report the clinical findings and course of two patients with early bleb related inflammation secondary to retained cellulose sponge fragments used to apply mitomycin C on the scleral surface.

METHODS

Retrospective review of medical records of two patients and pathology from one patient.

RESULTS

Both patients developed bleb related inflammation four months after a combined fornix based trabeculectomy and cataract procedure in which mitomycin C was applied using filter paper discs (Whatman filter paper #1). Material suggestive of cellulose fragments was noted in the filtering bleb in both patients. Patient 1 had a bleb leak at time of presentation and pathologic examination of foreign body material obtained from the site of the leak demonstrated a granulomatous reaction surrounding cellulose fibers. The foreign body material was removed in both patients. This led to resolution of the bleb leak in the first patient and at one year following the procedure both patients had functioning blebs in the affected eye.

CONCLUSIONS

Retention of sponge fragments is rare but may be a cause of bleb inflammation as a result of a foreign body granulomatous reaction. The choice of sponge material that does not shred may help in avoiding this unusual complication.

In vitro release of mitomycin C from collagen implants

PURPOSE

To study Mitomycin C Loaded Collagen Implant (CI) pharmacokinetics behaviour in vitro.

METHODS

The CI were incubated for 15 minutes in different MMC loading solutions with the following concentrations: 0.03 mg/mL (n = 9), 0.3 mg/mL (n = 10) and 3.0 mg/mL (n = 10). The loaded CI were transferred in 100 micro L of 0.9% NaCl. Aqueous flow of 5 micro L/min was simulated. The MMC concentrations of the samples were determined by high performance liquid chromatography (HPLC). Dissolution kinetics were evaluated by a first-order process. The half-life of dissolution and the time of 95% dissolution were determined.

RESULTS

The CI absorbed on average a MMC dose of 0.054, 0.530 and 6.090 micro g when incubated in the different MMC loading solutions containing 0.03 mg/mL, 0.3 mg/mL, 3.0 mg/mL of MMC, respectively. In the release experiments, the mean total dose delivered by CI was 0.0493, 0.585 and 5.291 micro g. A linear correlation between loading concentration and the estimated total dose released was demonstrated. The kinetic parameters showed a fast MMC dissolution. The half-life of the 3 series was 8.8, 10.1 and 10.5 min.

CONCLUSIONS

Commercially available CI can be loaded with MMC, and could provide relatively slower release than sponge delivery of MMC. Clinical implications of these results warrants further studies.

In vitro diffusion of mitomycin-C into human sclera after episcleral application: impact of diffusion time

The purpose of this study was to investigate the impact of different diffusion times of mitomycin-C (MMC) on the intrascleral concentration vs depth profile of MMC in an experimental model. Scleral quadrants of eight human donor eyes were exposed to sponges soaked with MMC for an application time of 1 min. After irrigation with 40 ml saline, we allowed further diffusion of MMC in the sclera for 1, 5, 14 and 29 min until the specimens were further processed. A central 8 mm diameter scleral disk was horizontally dissected with a kryotome at -20 degrees C. MMC concentrations of six layers of 140 microm thickness were analysed by means of high-performance liquid chromatography. The MMC concentrations (microg g(-1)) of layer 1 were: 13.45+/- 5.9 (mean +/- S.D. at 2 min diffusion time), 7.6+/-2.5 (6 min diffusion), 5.6+/-3.1 (15 min diffusion) and 3.6+/-1.7 (30 min diffusion). The corresponding MMC concentrations of layer 6 were: 0.61+/-0.48, 1.47 +/-0.66, 1.83+/-0.42 and 2.98+/-0.97 microg g(-1). The superficial concentration of intrascleral MMC decreased with increasing diffusion time, the deep concentrations increased. After 30 min of diffusion time, equal concentrations of MMC were found in all layers. Even with current low-dose application regimens of MMC the concentrations in the inner side of the sclera rapidly increase beyond the limits of the therapeutic range. Owing to this fast diffusion of MMC, the only means of reducing ciliary body concentrations of MMC is to reduce the dose.

Intrascleral concentration vs depth profile of mitomycin-C after episcleral application: impact of irrigation

Mitomycin-C has been reported to cause toxic effects on the ciliary body after episcleral application during glaucoma surgery. We investigated the intrascleral diffusion of mitomycin-C in an experimental model. The episcleral sides of scleral quadrants of 14 human donor eyes were exposed for 5 min to sponges (corneal light shield, Merocel corp., Mystic, CT, U.S.A.) soaked with 200 microg ml(-1)mitomycin-C. After the exposure one of four quadrants was not irrigated and the episcleral sides of three quadrants were irrigated with 40, 100 and 200 ml saline. A 9 mm scleral disk was punched out with a trephine and frozen on a kryotome plate 2 min after the end of mitomycin-C exposure. An 8 mm diameter scleral disk was then cut with a trephine, again frozen on a kryotome plate and then horizontally dissected with a kryotome. For analysis purposes seven cuts of 20 microm thickness were combined to one layer of 140 microm. Six layers could be reproduced and were analysed. The mitomycin-C concentrations of these layers were analysed by high-performance liquid chromatography. A concentration vs depth profile was calculated for each group, and the half-width of concentration was calculated by log-linear regression. The mitomycin-C concentration of layer 1 was 24.51 microg g(-1)(+/-7.52) without irrigation, 13.15 microg g(-1)(+/-4.38) after 40 ml irrigation, 10.29 (+/-3.53) after 100 ml irrigation and 8.4 microg g(-1)(+/-1.62) after 200 ml irrigation. In layers 1-3 the concentration of mitomycin-C was significantly reduced by irrigation (ANOVA). In the deeper intrascleral layers irrigation had no effect on the mitomycin-C concentrations. Between layers 2 and 6 the half-width of the mitomycin-C concentration was 101 microm (no-irrigation group), 141 microm (40 ml irrigation group), 153 microm (100 ml irrigation group), and 164 microm (200 ml irrigation group). Irrigation reduced the mitomycin-C concentration only down to half of the scleral thickness, leaving the deep intrascleral concentrations unchanged.

Glaucoma surgery: are there new perspectives in perioperative pharmacology?

The literature directed at perioperative pharmacologic advances in relation to glaucoma filtration surgery is reviewed. The successful use of subconjunctival anesthesia demonstrates a new alternative in preoperative glaucoma surgical anesthesia. The intraoperative use of the antimetabolites mitomycin C and 5-fluorouracil in both traditional filtration and glaucoma drainage implantation surgery has been expanded. The use of the antifibrinolytic agents urokinase and recombinant tissue plasminogen activator adds a new and controversial dimension to postoperative pharmacologic therapy.