Long-term intraocular pressure control of eyes that developed encapsulated blebs following trabeculectomy. Argon laser trabeculoplasty or trabeculectomy a prospective randomised block study. Long-term functional outcome after early surgery compared with laser and medicine in open-angle glaucoma. Early trabeculectomy versus conventional management in primary open angle glaucoma. A randomized study of trabeculectomy and subconjunctival administration of fluorouracil in primary glaucomas. Ahmed glaucoma valve implant vs trabeculectomy in the surgical treatment of glaucoma: a randomized clinical trial. Beta radiation as an adjunct to low-risk trabeculectomy. Long-term follow-up of primary glaucoma surgery with Ahmed glaucoma valve implant versus trabeculectomy. 5-fluorouracil in combined trabeculectomy and clear-cornea phacoemulsification with posterior chamber intraocular lens implantation. A one-year randomized, controlled clinical trial.
To evaluate the long-term intraocular pressure (IOP) control of eyes that developed an encapsulated bleb (EB) following trabeculectomy.
                Between 1994 and 1995, 25 eyes developed EBs and were randomized to medical treatment or needling without adjunct antimetabolites. Among the 25 patients who developed an EB, 21 were followed for at least 6 months. A control group of 21 consecutive eyes, which underwent trabeculectomy during the same period and that did not develop EBs was retrospectively selected. Success was defined as IOP <21 mmHg with or without medications. Kaplan-Meier survival analysis was performed to compare the groups.
                Among the 21 eyes that developed EBs, 12 (57%) had undergone transconjunctival needling and nine (43%) had received medical treatment. Mean follow-ups were 30.0 +/- 14.0 months, 33.3 +/- 18.5 months, and 37.4 +/- 2.6 months for the needling, medical treatment, and control groups, respectively (P = 0.19). Kaplan-Meier survival curves demonstrated that the control group showed a significantly lower chance of failure than both the needling and the medical treatment groups (P < 0.0001).
                Encapsulated blebs may be associated with an increased risk for surgical failure. A prospective randomised block study of treatment by either argon laser trabeculoplasty or trabeculectomy was undertaken in patients with chronic open angle glaucoma not controlled by medication. The study was undertaken in two centres in the United Kingdom where the regimes of medical treatment prior to interference were different. Regression analysis showed that in both populations laser trabeculoplasty was effective in reducing the intraocular pressure but it was less effective than trabeculectomy in permanently reducing the intraocular pressure to within normal limits. Laser trabeculoplasty was most effective in those patients whose intraocular pressure was initially high but many of these required post-operative medication or surgery. Laser trabeculoplasty is a useful adjunct to the therapy of open angle glaucoma but it is not a substitute for trabeculectomy as a method of permanently reducing the intraocular pressure to normal. Because of the effectiveness of both these methods of treatment we feel it no longer justified to use anything other than simple local medication to control the intraocular pressure before proceeding to active therapy. This randomly allocated prospective clinical study was designed to assess the relative efficacy of laser trabeculoplasty, medical therapy, and trabeculectomy used as the primary treatment in open-angle glaucoma, with particular regard to the level of intraocular pressure control and the amount of visual field decay. No patient had received any antiglaucoma treatment before entry into the trial.
                One hundred sixty-eight patients were entered into the trial and randomly allocated into one of the three treatment groups--laser, medicine, or surgery. Follow-up was for a minimum of 5 years. The patients were monitored in the standard way, including intraocular pressure estimations and visual field tests (initially using the Friedmann analyzer and later including Humphrey automated perimetry).
                Despite similar initial composition of the three treatment groups, primary surgery resulted in the lowest mean intraocular pressures. The perimeter Friedmann visual fields were shown to have deteriorated in patients in the medicine-treated group and to a lesser extent in patients in the laser-treated group, but not in patients in the surgery-treated group. Multivariate linear regression analysis showed that the difference in field changes between laser and surgical treatments could be explained entirely by the difference between the intraocular pressure values at 6 months between the two groups. The same was not true for the medicine-treated group.
                Primary trabeculectomy appears to have the desired effect in preserving visual function in patients with high-tension glaucoma. This may be related to laser treatment might be expected to have the same effect. The results of a randomised, prospective, multicentre trial of the management of primary open angle glaucoma are presented at up to five years' follow up. Previously undiagnosed cases were selected with intraocular pressure of 26 mmHg or more on two occasions together with field loss characteristic of glaucoma. Analysis was performed on one eye selected at random from each of 99 patients. Conventional medical treatment followed in unsuccessful cases by trabeculectomy (group A) was compared with trabeculectomy at diagnosis followed when necessary by supplementary medical therapy (group B). The life expectancy of these glaucoma patients was found to be similar to that for the local population matched for age and sex. In group A after four years trabeculectomy had been performed in 53% of eyes because medical management had failed to control the disease. The rate of operation was lower in those patients with intraocular pressure less than 31 mmHg and mild relative field loss (17% at three years) than in those with intraocular pressure greater than 30 mmHg and dense scotomas (75% at three years). Early surgery provided much more stable control with fewer changes in treatment than in group A. The group mean intraocular pressure after trabeculectomy was 15.0 mmHg irrespective of the time of operation, and this was significantly lower than the intraocular pressure in those cases thought to be controlled on medical therapy alone at the end of the first year (20.8 mmHg). Early operation provided significantly better protection of visual field, and the extra loss of visual field with delayed operation occurred in the preoperative period. Changes in visual fields were not related to the use of miotics. There was no significant difference in the final visual acuity in the two groups, but six cases in group A lost central fixation because of progressive loss of visual field, and there were no such cases in group B. Cataract occurred in approximately 10% of cases in both groups, but in group A this happened with only half the number of operations and at a shorter postoperative follow-up than in group B. It appears that in cases of primary open angle glaucoma of this severity the risk of delaying operation are significantly greater than those of performing trabeculectomy as the primary treatment. Forty-one adult patients with primary open angle glaucoma and nine adult patients with chronic angle closure glaucoma underwent trabeculectomy in one eye each. Twenty-one eyes with primary open angle glaucoma and four with chronic angle closure glaucoma were randomly assigned to receive four to six subconjunctival injections of fluorouracil for 10 days after surgery. Twenty-five control eyes did not receive fluorouracil. Intraocular pressure was 20 mm Hg or lower in 24 eyes (96%) in the treatment group after mean follow-up of 17.8 months and in 19 control eyes (76%) after mean follow-up of 17.5 months (P less than .05). Encapsulated bleb developed in three (12%) of the fluorouracil-treated eyes vs two (8%) of the control eyes. A few injections of fluorouracil adequately inhibited scarring. This might be explained by its toxic effect on existing fibroblasts. Overall, trabeculectomy with injection of fluorouracil was found to be efficacious and relatively safe. Further studies regarding late complications are required. To compare the short- and intermediate-term results of two commonly used glaucoma surgical procedures, trabeculectomy and Ahmed glaucoma valve implant.
                A randomized clinical trial was performed at two international centers. One eye each of consecutive patients requiring glaucoma surgery for intraocular pressure control was randomized to receive either trabeculectomy or the Ahmed implant.
                Of the 117 patients, 62 were randomized to trabeculectomy and 55 to the Ahmed implant. With a mean follow-up of 9.7 months, the trabeculectomy group had statistically lower intraocular pressures at weeks 6 to 15 (12.6 mm Hg vs 16.4 mm Hg) and months 11 to 13 (11.4 mm Hg vs 17.2 mm Hg) than the Ahmed implant group. Compared with preoperative status, no statistically significant differences between groups were noted for visual acuity, visual field, lens status, and final anterior chamber depth. The cumulative probabilities of success (intraocular pressure <21 mm Hg and at least 15% reduction in intraocular pressure from preoperative level) were 83.6% for trabeculectomy and 88.1% for Ahmed implant (P =.43). However, the Ahmed implant group had a greater adjunctive medication requirement. On the last visit, 10 of the trabeculectomy eyes and 19 of the Ahmed implant eyes required at least one topical medication (P =.01). There was no statistically significant difference in the rate of complications between the two groups.
                Lower mean intraocular pressures were noted for the trabeculectomy group. All other results, including success (as defined in this study) and frequency of complications, were comparable between the two groups. To assess a single dose of intraoperative beta radiation used to enhance the success rate of trabeculectomy in a population of low-risk glaucoma patients in whom antimetabolites might not be indicated.
                A prospective randomized trial of 65 eyes was designed, with 31 eyes receiving 750 rads of intraoperative beta radiation (group 1), and 34 eyes receiving no supplementation (group 2).
                Mean follow-up time was 24 months. Mean postoperative intraocular pressure was 12.2 mmHg in group 1, and 13.7 mmHg in group 2 (P = 0.16). Mean decrease in intraocular pressure was 10.3 mmHg in group 1, and 9.3 mmHg in group 2 (P = 0.49). The two groups were not significantly different in terms of surgical complications.
                For this population of low-risk patients, there was no significant difference in outcome after applications of a single intraoperative dose of beta radiation. To compare the long-term results of trabeculectomy and Ahmed glaucoma valve implant in the initial surgical management of primary open- and closed-angle glaucoma.
                Randomized controlled clinical trial.
                One eye each of consecutive patients with primary glaucoma and without prior intraocular surgery was randomized to receive either trabeculectomy or the Ahmed implant. Large university-affiliated eye hospital in Columbo, Sri Lanka.
                Of 123 patients, 64 were randomized to trabeculectomy and 59 to the Ahmed implant. With a mean follow-up of 31 months, the trabeculectomy group had statistically lower intraocular pressures (IOP) during the first postoperative year. After the first year, the IOPs were comparable. No statistically significant differences between groups were noted for postoperative visual acuity, visual field, anterior chamber depth, and short-term or long-term complications. Adjunctive medication requirement was comparable for both groups. The cumulative probabilities of success (IOP <21 mm Hg and at least 15% reduction in IOP from preoperative levels) at the final follow-up period (months, 41-52) were 68.1% for trabeculectomy and 69.8% for Ahmed implant (P =.86).
                Lower IOPs were noted for the trabeculectomy group during the first year. With longer follow-up, the IOPs and the cumulative probabilities of success were comparable between the two groups. To test the effect of postoperative subconjunctival 5-fluorouracil (5-FU) on the pressure outcome in combined procedure (limbus-based trabeculectomy + clear-cornea phacoemulsification).
                Prospective randomized, controlled clinical trial; n = 24 eyes (24 patients) with concurrent open-angle glaucoma and cataract; 12 eyes per treatment group; sample size adjusted for a minimal expected difference in the event rate between the 2 treatment groups = 50%, control rate = 20%; type I error = 0.05; power = 95%. Uncomplicated limbus-based trabeculectomy + uncomplicated clear-cornea phacoemulsification + posterior chamber intraocular lens. The 5-FU group = five subconjunctival injections of 5 mg 5-FU, starting from day 8 after surgery, one injection per week. Control group = no injections. The groups were matched for age, preoperative intraocular pressure (IOP), duration of preoperative antiglaucoma treatment, preoperative pilocarpine and adrenergics, preoperative laser trabeculoplasty, and beta-blockers in the fellow eye. The IOP less than or equal to 15 mmHg without treatment 1 year after surgery (IOP = average of the two highest values measured in the diurnal curve, 8 AM to 6 PM, one reading every 2 hours).
                Each patient completed a 1-year follow-up. Ten of 12 eyes of the 5-FU group showed an IOP less than or equal to 15 mmHg at the end of follow-up versus 1 of 12 eyes in the control group (Fisher's exact test, P = 0.00064). The IOP range was 10 to 17 mmHg in the 5-FU group and 14 to 22 mmHg in the control group.
                Postoperative 5-FU may improve the 1-year success rate of trabeculectomy combined with clear-cornea phacoemulsification.
Evidence from one small trial suggests that needling of encapsulated trabeculectomy blebs is not better than medical treatment in reducing intraocular pressure.