Non-enhanced trabeculectomy by non-glaucoma specialists: are results related to risk factors for failure?

Long-term outcomes of glaucoma drainage devices for glaucoma post-vitreoretinal surgery with silicone oil insertion: a prospective evaluation

PURPOSE

To evaluate long-term success of the Ahmed glaucoma valve (AGV) for refractory glaucoma after vitreoretinal surgery with silicone oil insertion.

METHODS

Prospective non-comparative evaluation of patients who underwent AGV insertion for management of post-vitreoretinal surgery glaucoma, post-silicone oil removal. Intraocular pressure (IOP), visual acuity, and glaucomatous neuropathy status were evaluated preoperatively and at multiple follow-up visits postoperatively. Success, using Kaplan-Meier analysis, was determined at the 12-month follow-up visit and at the last follow-up. Factors associated with failure were analysed.

RESULTS

Twenty-seven eyes of 27 patients with a mean age of 28.3 ± 15.2 years underwent a superior AGV implantation. The average follow-up after AGV implantation was 17.11 ± 8.36 months (range: 9-60 months). Kaplan-Meier survival analysis revealed a 62 % success at 12 months and 37 % at 5 years. A 48 % rate of complications was noted, 22 % of which were vision-threatening. Factors analysed, including patient age, interval between vitreoretinal surgery and silicone oil removal, interval between vitreoretinal surgery and AGV implantation, and phakic status, were not found to be associated with higher failure rates.

CONCLUSION

Long-term success of AGV implantation for glaucoma after vitreoretinal surgery with silicone oil insertion is better than that reported for trabeculectomy, though complication rates remain high.

Prognostic factors for trabeculectomy failure in a Cuban population

OBJECTIVE

To identify the prognostic factors for mid-term trabeculectomy failure.

METHOD

A prospective cohort study was conducted on 113 eyes (113 patients) that had undergone a trabeculectomy for primary open or closed angle, pigmentary, or juvenile glaucoma. Surgical failure was defined if intraocular pressure was equal or more than 18mmHg with medication (two or more drops), after 1-4 postoperative years. The relative risk was calculated and a logistic regression analysis was performed.

RESULTS

Previous trabeculectomy, preoperative intraocular pressure ≥ 31mmHg, black race, and advanced glaucoma increased the failure risk by 7.9 times (P=.036), 5.3 times (P=.011) and 4.7 times (P=.028, and P=.027), respectively. The addition of two or more factors increased the risk by 6.4 times (P<.001). It was not affected by age, sex, pre-operative drops, or surgical complication.

CONCLUSIONS

Previous trabeculectomy, pre-operative intraocular pressure ≥ 31mmHg, black race, and advanced glaucoma are prognostic factors for trabeculectomy failure, in decreasing order of their association with surgical failure. The addition of two or more factors increased the risk of failure. In those situations, the use of trans- operative anti-metabolites is suggested.

Moving the goal posts definitions of success after glaucoma surgery and their effect on reported outcome

PURPOSE

To determine (1) the extent to which the definition of success of glaucoma surgery varies in the literature and (2) the degree to which the reported outcome after trabeculectomy is affected by the criteria used to define success.

DESIGN

A systematic review of the literature and application of definitions to a retrospective cohort.

PARTICIPANTS

A cohort of 100 patients who previously underwent trabeculectomy.

METHODS

A literature search was performed of PubMed using the search term trabeculectomy for a 5-year period. Studies presenting original data relating to longitudinal intraocular pressure (IOP) control after glaucoma surgery were included. The definitions of success and failure used were documented for each publication. Each IOP-related definition of success was applied to a cohort of patients who previously underwent trabeculectomy. Success rates were derived for each published definition up to 36 months after surgery.

MAIN OUTCOME MEASURES

Intraocular pressure measured by Goldmann applanation tonometry.

RESULTS

From 100 publications meeting the inclusion criteria, 92 distinct IOP-related definitions of success were identified. Using these definitions, success rates for this series of 100 trabeculectomies varied between 36.0% and 98.0% after 3 years of follow-up.

CONCLUSIONS

Over a recent 5-year period, there were nearly as many different definitions of success after glaucoma surgery as publications on the subject. The definition used markedly affects the quoted success rate after trabeculectomy, making interpretation of and comparison between published results extremely difficult. Standardization of published outcome parameters after glaucoma surgery is essential to allow meaningful comparisons between different study reports.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Evaluation of efficacy and safety of daunorubicin in glaucoma filtering surgery

PURPOSE

To evaluate the intraocular pressure (IOP)-lowering effect and ocular side effects of daunorubicin (DNR) in drug-modulated trabeculectomy.

METHODS

A prospective pilot study was conducted in which 21 Asian patients of Indian origin with high risk factors for failure of trabeculectomy were recruited. An approval from research ethics committee and an informed consent from every patient included in the study were obtained. DNR, an antimetabolite with known antifibroblastic action was used intraoperatively. A limbus-based conjunctival flap followed by conventional trabeculectomy was performed in all eyes. During trabeculectomy, a cellulose sponge soaked in 0.2 mg/ml DNR was applied for 3 min at the proposed site of trabeculectomy before preparation of the partial thickness scleral flap. A regular follow-up was carried out for 1 year where parameters including visual acuity, IOP by applanation tonometry, and slit lamp examination were performed on each visit. An IOP of 21 mmHg or less was taken as criteria for success.

RESULTS

Following DNR trabeculectomy, the IOP was lowered from baseline preoperative value of 36.19+/-5.9 to 16.05+/-2.52 mmHg at the end of 1 year. Success rate of 81% (17 out of 21 patients) was noted. None of the patients developed corneal epithelial toxicity, hypotony maculopathy, or choroidal detachment.

CONCLUSION

The authors feel that intraoperative daunorubicin is safe and effective in lowering IOP in high-risk surgical cases of glaucoma. However, a much larger cohort study over a considerable number of years will eventually demonstrate its safety.

The relation of volume and outcome in trabeculectomy

BACKGROUND/AIMS

Higher case volume has been associated with improved outcomes for a number of procedures. This study was designed to investigate whether this relationship existed for trabeculectomy.

METHODS

The study was retrospective and conducted at an ophthalmic unit in the UK. All patients who had unenhanced trabeculectomy between 1996 and 2000 were identified. From their notes, the surgeon who performed the trabeculectomy was ascertained as were any unplanned interventions (eg conjunctival suturing, anterior chamber reformation, repeated attendances) within the first month of surgery.

RESULTS

Two hundred and eleven trabeculectomies were performed over the study period. Twenty nine had unplanned interventions within the first postoperative month. Analysis of the data indicated that surgeons who performed less than eight operations per year had more complications than those who performed more than 10 per annum. This difference was only significant (chi(2)=4.0, P=0.045) when the data were aggregated. When separated per year, although not significant, the complication rate of the lower volume group was always higher than the group performing more than 10 per year.

CONCLUSIONS

The results suggest that trabeculectomy can be added to the list of procedures in which larger case volume is associated with fewer early complications and potentially a better outcome. The findings, if replicated, tend to strengthen the argument for subspecialisation in glaucoma with its implications for training and revalidation.