Trabeculectomy For Open-angle Glaucoma Research Articles

Nonpenetrating deep sclerectomy: a 6-year retrospective study.

Nonpenetrating trabeculectomy, also called nonpenetrating deep sclerectomy (NPDS), is a filtering surgery where the internal wall of Schlemm's canal is excised, allowing subconjunctival filtration without actually entering the anterior chamber. This, technique was developed to minimize the complications of trabeculectomy. The authors investigated its safety and efficacy in a retrospective noncomparative study. A total of 258 eyes (179 patients, mean age 61.4 +/- 11.56 years) with uncontrolled open angle glaucoma with prior medical therapy were treated. NPDS with a biocompatible collagen device (157 eyes) sutured to deep scleral bed or with the use of a 5-fluorouracil sponge (90 eyes) were analyzed. The main outcome measure was postoperative intraocular pressure (IOP) with an average follow-up of 54.4 +/- 17.07 months (range 1-85). Efficacy was determined 1 month, 3 months, and every 6 months after the procedure for 6 years. Mean preoperative IOP was 24.47 +/- 5.92 mmHg. Mean postoperative IOP was 14.44 +/- 5.31 mmHg (average lowering of the IOP was 38.94 +/- 23.81%) at 1 month, 15.16 +/- 4.57 mmHg (35.73 +/- 21.35%) at 3 months, 15.87 +/- 4.24 mmHg (32.45 +/- 20.52%) at 6 months, 16.32 +/- 4.53 mmHg (29.96 +/- 23.69%) at 12 months, 17.12 +/- 4.45 mmHg (26.51 +/- 23.93%) at 18 months, 16.77 +/- 4.44 mmHg (28.18 +/- 21.73%) at 24 months, 16.43 +/- 4.15 mmHg (28.89 +/- 23.69%) at 30 months, 16.34 +/- 4.12 mmHg (30.05 +/- 21.61%) at 36 months, 16.16 +/- 4.01 mmHg (30.06 +/- 22.55%) at 42 months, 15.71 +/- 3.74 mmHg (32.49 +/- 19.08%) at 48 months, 15.61 +/- 3.48 mmHg (31.26 +/- 21.01%) after 5 years, and 15.81 +/- 3.79 mmHg (33.73 +/- 20.9%) after 6 years. YAG goniopuncture was performed in 47.3% of cases with a mean follow-up of 12 +/- 13 months. These goniopunctures were effective in lowering IOP after a long-term follow-up (24 months). Additional 5-fluorouracil injections were used in 7% of cases. Visual field (Octopus or Humphrey mean defect and corrected loss variance or loss variance) was not modified (p < 0.01). Number of preoperative glaucoma medications was 2.01 +/- 0.58 and number of postoperative glaucoma medications was 0.85 +/- 0.92. Complications were peroperative microperforations in 27 eyes (10.5%), shallow anterior chamber in 2 eyes, hyphema in 2 eyes (0.8%), cataract in 5 eyes (2%), and dellen in 1 eye (0.4%). No cases of endophthalmitis or choroidal detachment were found. After surgery, 23 eyes (8.9%) required a new filtering surgical procedure, and diode laser cyclophotocoagulation was necessary in 2 eyes (0.8%). The probability success rate, defined as an IOP lower than 21 mmHg, was 66.46% (Kaplan Meier) at 60 months off all glaucoma medications and 80.32% with medical or new surgical treatment. NPDS appears to be an effective and safe filtering procedure for lowering IOP and could be an alternative to trabeculectomy in open angle glaucoma with the advantage of having fewer complications.

The National Survey of Trabeculectomy. III. Early and late complications.

There is a considerable body of literature relating to trabeculectomy, however there are no data representative of the national experience of trabeculectomy in the United Kingdom (UK). The Department of Health funded a national survey of trabeculectomy to establish current practice patterns and the outcome of trabeculectomy in the National Health Service (NHS). In this paper we present the reported complications of first-time trabeculectomy from a nationally representative cohort of patients with chronic open angle glaucoma. Cross-sectional study of consultant ophthalmologists performing trabeculectomy in the NHS. Participants recruited their four most recent consecutive first-time trabeculectomy cases with chronic open angle glaucoma according to study eligibility criteria and data were collected by self-administered questionnaire. one year post-trabeculectomy. occurrence of early and late complications. Clinical outcome data were available for 1240 (85.3%) of cases. Early complications were reported in 578 (46.6%) cases and late complications in 512 (42.3%) cases. Some cases had more than one complication. The most frequent early complications were hyphaema (n = 304, 24.6%), shallow anterior chamber (n = 296, 23.9%), hypotony (n = 296, 24.3%), wound leak (n = 216, 17.8%) and choroidal detachment (n = 175, 14.1%). The most frequent late complications were cataract (n = 251, 20.2%), visual loss (n = 230, 18.8%) and encapsulated bleb (n = 42, 3.4%). The occurrence of most complications was not associated with a consultant's specialist interest, level of activity, type of hospital or region. Encapsulated bleb was reported more frequently in a university hospital setting. The complication rates reported in this paper represent the national experience of first-time trabeculectomy for open angle glaucoma in the UK. These are similar to previous published studies and highlight in particular, the impact of trabeculectomy on visual acuity in the first year following surgery. This survey provides valid and clinically relevant data on the complications of trabeculectomy for the production of guidelines and standards for audit at regional, local and individual level.

Randomized controlled clinical trial of beta irradiation as an adjunct to trabeculectomy in open-angle glaucoma

Objective To assess the effect of a single intraoperative application of 750 cGy of beta irradiation on the outcome of trabeculectomy for uncontrolled open-angle glaucoma. Design A prospective, randomized, double-blind, placebo-controlled clinical trial. Participants Sixty-one eyes of 61 Caucasian patients at low risk of filtering surgery failure, with poorly controlled primary or secondary open-angle glaucoma undergoing routine trabeculectomy. Method Patients were randomly assigned to control or beta irradiation groups. All patients underwent standard trabeculectomy with fornix-based conjunctival incision. Eyes assigned to beta irradiation received 750 cGy of beta irradiation directly over the sclerostomy site on completion of conjunctival suturing. An identical but inactive applicator was applied to control eyes, delivering no radiation. Both operator and patient remained masked to the assignment for the 12-month follow-up period. Main outcome measures The main outcome measure was intraocular pressure (IOP) control. Complete success of IOP control was defined as an IOP less than 21 mmHg at 12 months without need for additional medication. Qualified success was defined as an IOP less than 21 mmHg at 12 months where additional medication was required. Results Complete success of IOP control was achieved in 19 (86%) control eyes and 35 (90%) irradiated eyes ( P = 1.0). Qualified success of IOP control was achieved in 21 (95%) control eyes and 39 (100%) irradiated eyes at 12 months follow-up ( P = 1.0) Conclusions We experienced a very high success rate of filtration surgery in this select population without adjunctive irradiation. Our sample size was too small to show any improvement in success with use of beta irradiation in this group. Other studies would have to be done to determine whether it may have measurable benefit in cases with a high risk of filtration failure.

The National Survey of Trabeculectomy. II. Variations in operative technique and outcome.

There is a considerable body of literature relating to trabeculectomy; however, there are no data representative of the national experience of trabeculectomy in the United Kingdom (UK). The Department of Health funded a national survey of trabeculectomy to establish current practice patterns and the outcome of trabeculectomy in the National Health Service (NHS). In this paper we report variations in surgical technique and the national success rate of trabeculectomy. A cross-sectional survey was carried out of consultant ophthalmologists performing trabeculectomy in the NHS. Participants recruited their four most recent consecutive first-time trabeculectomy cases according to study eligibility criteria and data were collected by self-administered questionnaire. 1 year post-trabeculectomy. Main outcome measure of success: final intraocular pressure (IOP) less than two-thirds the pre-operative IOP. Secondary outcome measures of success: final IOP less than 21 mmHg and visual field stability. Success was further defined as unqualified (excluding patients on anti-glaucoma medications at final follow-up) or qualified (including patients on anti-glaucoma medications at final follow-up). The relationship between variables characterising consultants' practice and main outcome measure was examined by chi-square test. Clinical outcome data were available for 1240 (85.3%) cases. There were wide variations in operative technique. The mean post-operative IOP was 14.4 mmHg (95% CI 14.2-14.7), which is a mean reduction of 11.8 mmHg (95% CI 11.4-12.2). An unqualified success, in terms of the main outcome measure, was achieved in 66.6% of patients and a qualified success in 71.0% of cases. An unqualified success, in terms of a final IOP less than 21 mmHg, was achieved in 84.0% of cases and a qualified success in 92.0%. Visual fields were stable in 84.2%. Outcome was not related to consultants' specialist interest, level of activity, type of hospital or region. The success rates reported in this paper represent the national experience of first-time trabeculectomy for open angle glaucoma in the UK. The national success rate at 1 year compares favourably with many studies in the literature. This survey provides valid and clinically relevant measures of success for the production of guidelines and standards for audit at regional, local and individual level and a baseline for the comparison of new therapies.

Comparison of deep sclerectomy with collagen implant and trabeculectomy in open-angle glaucoma

Purpose: To assess the efficacy and postoperative complications of deep sclerectomywith collagen implant (DSCI), a nonpenetrating filtration procedure. Setting: Glaucoma Unit, Department of Ophthalmology, University of Lausanne, Switzerland. Methods: Forty-four eyes of 44 patients with medically uncontrolled open-angle glaucoma had DSCI and a matched control group of 44 patients, trabeculectomy. A superficial scleral flap was raised and a deep sclerectomy performed in the scleral bed. Schlemm's canal was opened, and the cornea was dissected to Descemet's membrane. At that stage, aqueous filtered through the remaining trabeculo-Descemet's membrane. A collagen implant was sutured radially in the scleral bed; the scleral flap and conjunctiva were then closed. Examinations were performed before surgery and postoperatively at 1 and 7 days and 1, 2, 3, 6, 9, 12, 15, 18, and 24 months. Results: The mean follow-up was 14.4 months ± 6.3 (SD) (range 3 to 24 months). The mean preoperative intraoperative pressure (IOP) was 26.7 ± 7.3 mm Hg. The mean postoperative IOP was 6.1 ± 4.5 mm Hg at 1 day and 11.0 ± 4.4 mm Hg at 1 week; it remained stable for the next 24 months. The success rate, defined as an IOP lower than 21.0 mm Hg without medication, was 69% in the DSCI group and 57% in the trabeculectomy group at 24 months postoperatively ( P = .047). The number of postoperative complications was significantly lower in the DSCI group than in the trabeculectomy group. Conclusions: The success rate of DSCI may be comparable to that of trabeculectomy, with fewer complications.

A Review of the Outcome of Trabeculectomy in Open-Angle Glaucoma

The outcome of trabeculectomy in the treatment of primary open-angle glaucoma and exfoliative glaucoma was reviewed. The study included 87 consecutive eyes of 87 patients with open-angle glaucoma. The outcome of trabeculectomy was correlated with a biomicroscopic appearance of the filtering bleb. Visual acuity, myopic shift in refraction, and lens opacity measurements were used as indicators for cataract progression. The effect of viscoelastics on complications and short-term outcome was studied in a randomized series of 107 eyes. In a series of 87 eyes, 61% had intraocular pressure (IOP) of less than 22 mm Hg without glaucoma medication 1 year after surgery. After 3 years, the corresponding success rate was 74% in a series of 85 eyes that had preoperative pupillary dilation of 4 mm or more. The diffuse filtering bleb type was associated with the greatest decrease in IOP. Unfavorable flap-sized blebs and bleb failures were associated with preoperative treatment with miotics, anterior fistulation, and postoperative hypotony. These patients also tended to be younger. In a randomized, prospective study of 107 eyes, the use of sodium hyaluronate had no significant effect on the incidence of complications or on the short-term outcome. Age 61 years or older, exfoliative glaucoma, postoperative hypotony, and IOP peaks were identified as risk factors for accelerated cataract progression after trabeculectomy.

Conjunctival changes after subconjunctival lignocaine.

Subconjunctival injection of 2% lignocaine at the 12 o'clock position was used as the local anaesthetic in 19 eyes undergoing a primary trabeculectomy for open angle glaucoma. The appearance of the bleb and mean post-operative intraocular pressure (IOP) were compared with those in 29 eyes with the same diagnosis undergoing trabeculectomy under general anaesthesia by the same surgeons over the same time period. The two groups of eyes were similar with regard to treatment with beta blockers (p > 0.1), miotics (p > 0.25), sympathomimetics (p > 0.25), carbonic anhydrase inhibitors (p > 0.5), or no treatment (p > 0.25). Seventy-seven per cent of the local anaesthetic group and 25% of the general anaesthetic group developed avascular, thin-walled drainage blebs (p < 0.001). The mean post-operative IOP was significantly lower in the group receiving local anaesthetic (p < 0.001). The reasons for and significance of these observations are discussed, and the merits and disadvantages of thin-walled blebs are evaluated.

Results of Intraoperative 5-Fluorouracil Supplementation on Trabeculectomy for Open-angle Glaucoma

The success rate of filtration surgery has been increased by the postoperative subconjunctival injection of 5-fluorouracil, a potent antimetabolite. However, the optimal route of administration has not been determined. Trabeculectomy was performed on one eye each of 14 patients. Topical 5-fluorouracil was applied intraoperatively (50 mg/ml for five minutes) and subconjunctival 5-fluorouracil was injected postoperatively (an average of 5.8 injections) (mean total dose, 29 mg). Seven of the 14 eyes had primary open-angle glaucoma, and seven eyes had open-angle glaucoma with either uveitis, aphakia, or previous failed trabeculectomy. Mean preoperative intraocular pressure was 24.7 mm Hg during treatment with an average of three antiglaucoma medications, and mean final intraocular pressure was 11.9 mm Hg during treatment with an average of 0.2 medication. Thirteen of 14 eyes (93%) had final intraocular pressure of 18 mm Hg or less. Mean follow-up was 6.4 months (range, four to nine months). No remarkable complications occurred. Visual acuity remained stable in 13 of 14 eyes (93%). Intraoperative 5-fluorouracil may be a helpful adjunct in achieving low final intraocular pressure after trabeculectomy.

Improvement of visual field following trabeculectomy for open angle glaucoma

Trabeculectomy was performed in 24 eyes affected by primary open angle glaucoma. Visual fields were measured using automated perimetry preoperatively and in the first, third, sixth and twelfth months after surgery. Significant improvement in visual field occurred in 96% of cases.

Pseudoexfoliation glaucoma in Greece.

Pseudoexfoliation glaucoma is commonly seen in Greece, however there is little data concerning the prevalence and characteristics of this disorder. Patients undergoing trabeculectomy for open angle glaucoma were investigated both by the appraisal of the case notes and by re-examination. The prevalence of pseudoexfoliation glaucoma in this population was found to be 87.8%. The characteristics of this disease process in the population studied are discussed. These findings indicate that pseudoexfoliation is a major contributor to severe glaucoma in the population of Northern Greece.