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Objective To assess the factors that can predict the success of external needle revision of failing blebs. Design Retrospective, nonrandomized, comparative case series. Participants Forty-nine eyes of 43 patients who underwent a needle revision of a filtration bleb with 5-fluourouracil (5-FU) by one physician (SVLB) between August 1993 and December 1994. Intervention Needle revision of a failing filtration bleb using 5-FU. Main outcomes The intraocular pressure, glaucoma medications, and any complications. Results The risk ratio of fornix-based trabeculectomies compared with limbus-based trabeculectomies was 3.781; P = 0.047. The risk ratios for gender, race, type of glaucoma, lens status, previous surgery, antimetabolite used for the initial trabeculectomy, and preoperative bleb characteristics were not statistically different for any one group. Conclusions Fornix-based trabeculectomies were more likely to fail the needle revisions compared with limbus-based trabeculectomies. None of the five preneedling bleb characteristics showed a propensity toward success or failure. Other demographics such as gender, race, type of glaucoma, previous surgery, antimetabolite used for the initial trabeculectomy, and lens status were also not predictive for success.

We describe the use of a new instrument designed to create a simultaneous goniopuncture with diathermy using an ab-interno technique. The goniodiathermy ab-interno procedure was first performed on three eyes of three cynomolgus monkeys. Intraocular pressure (IOP) assessment and histologic examination were performed over a 10-day period. A functioning filtration bleb with a patent sclerostomy was achieved in all of the experimental eyes. A pilot study involving four eyes of four glaucoma patients also was performed. Of these four, successful long-term functioning filtration areas with adequate lowering of IOP were achieved in only two. The remaining two required further surgical intervention. Although combining goniopuncture and diathermy into a one-step ab-interno procedure proved successful in the primates studied, the preliminary use of this new instrument as a method of creating a filter in humans raises questions regarding its clinical usefulness.

Purpose: The authors compared the effectiveness of limbus- and fornix-based conjunctival flaps in patients undergoing combined phacoemulsification, intraocular lens implantation, and mitomycin C trabeculectomy. Methods: The authors conducted a retrospective review of the records of 52 consecutive eyes of 45 patients who underwent combined surgery with limbus- and fornix-based conjunctival flaps. All surgery was by done by one surgeon on predominantly white patients in a suburban glaucoma subspecialty practice. Seven patients had both limbusand fornix-based surgery, permitting fellow eye comparisons in these patients. All patients had at least 6 months and a median of 17 months follow-up. None of the eyes that were operated on had undergone intraocular surgery previously. Results: No clinically significant difference in postoperative pressure reduction, bleb survival, or visual acuity was seen between the fornix- and limbus-based groups. Results in the fellow eye comparison subgroups were similar. The mean intraocular pressure decreased from 20.4 mmHg before surgery to a mean of 12.4 mmHg at the last followup visit. Forty-seven (90.3%) of 52 eyes had a final best-corrected visual acuity of 201 40 or better. Forty eyes (76.9%) no longer needed antiglaucoma medications at the end of follow-up. Five eyes had intraoperative posterior capsule rupture; all of these occurred in the limbus-based group. Shallow serous choroidal effusions were more common in the fornix-based group, but none were clinically significant. No difference in postoperative astigmatism between the limbus- or fornix-based group was seen. Intraoperative pupilloplasty, synechialysis, or postoperative neodymium:YAG capsulotomy had no appreciable effect on final intraocular pressure or bleb survival. Endophthalmitis, aqueous misdirection, or hypotony maculopathy did not develop in any patient. Conclusion: The effectiveness of limbus- and fornix-based conjunctival flaps appears to be similar. The limbus-based technique may result in a higher incidence of posterior capsular rupture, but the safety of limbus- and fornix-based flaps is otherwise similar. Combined phacoemulsification and mitomycin C trabeculectomy appears to be safe and effective for treating selected patients with coexisting glaucoma and cataract.

I report the use of partial-thickness Tenon'sconjunctival tissue in the repair of an intraoperative scleral-flap buttonhole that developed during trabeculectomy using adjunctive mitomycin C.

The short-pulse laser may prove superior to the argon laser in producing noninvasive iridectomies. Little is known of the effects of the laser shockwave on anterior segment structures adjacent to the iris. To investigate this question, iridectomies were produced in two owl monkeys using a neodymium (Nd):YAG laser and tissues were evaluated by light microscopy and scanning and transmission electron microscopy. For purposes of comparison, one eye received an iridectomy produced by an argon laser. Results indicate that while clean iris colobomas can be produced with a well-focused Nd:YAG laser, its shock-wave affects tissues in both the trabecular meshwork and corneal endothelium if the iridectomy is located within 0.8 mm of the limbus. No damage to the trabecular meshwork or corneal endothelium was evident after the argon laser iridectomy.

A prospective study was conducted in 30 eyes of 30 patients to determine if pilocarpine would prevent increased intraocular pressure following Q-switched neodymium (Nd):YAG laser posterior capsulotomy. Fifteen eyes were given pilocarpine 4%, immediately following laser therapy and every hour until bedtime. Fifteen eyes served as untreated controls. Our results show that without prophylactic therapy, 10 of 15 eyes (67%) had a post-laser intraocular pressure (IOP) elevation of greater than 10 mmHg, while only one of 15 (6.6%) of the pilocarpine-treated eyes had a rise of that magnitude. The facility of outflow was reduced by 42% in the untreated eyes in contrast to an increase of 3% in those eyes treated with pilocarpine. Thus, pilocarpine 4% is effective in reducing the incidence and magnitude of elevated IOP following Nd:YAG posterior capsulotomy.

Thirty-nine eyes of 34 patients with open-angle glaucoma who had been treated successfully with argon laser trabeculoplasty underwent either extracapsular cataract extraction with posterior chamber intraocular lens implantation or intracapsular cataract extraction without lens implantation. Cataract surgery did not have a significant effect on the magnitude of intraocular pressure reduction obtained with laser trabeculoplasty. This study supports the view that eyes with coexisting cataract and glaucoma may benefit from laser trabeculoplasty before cataract surgery.

Because of inadequate control of intraocular pressure, 26 eyes of 24 patients with primary and secondary open-angle glaucoma who had previously undergone argon laser trabeculoplasty were re-treated. Re-treatment was successful in ten eyes (38%); their average decrease in intraocular pressure was 10.2 mm Hg. After laser re-treatment, three eyes (12%) had marked increases in intraocular pressure, ranging from 10 to 37 mm Hg above baseline, necessitating urgent surgical intervention.