BACKGROUND: Glaucoma is an optic neuropathy that leads to visual field defects and vision loss. It is the second leading cause of irreversible blindness in the world. Treatment for glaucoma aims to reduce intraocular pressure (IOP) to slow or prevent further vision loss. IOP can be lowered with medications, laser, or incisional surgery. Trabeculectomy is a surgical approach which lowers IOP by shunting aqueous humor to a subconjunctival bleb. Device-modified trabeculectomy techniques are intended to improve the durability and safety of this bleb-forming surgery. Trabeculectomy-modifying devices include the Ex-PRESS, the XEN Gel Stent, the PreserFlo MicroShunt, as well as antifibrotic materials such as Ologen, amniotic membrane, expanded polytetrafluoroethylene (ePTFE) membrane, Gelfilm and others. However, the comparative effectiveness and safety of these devices are uncertain.
OBJECTIVES: To evaluate the benefits and harms of different devices as adjuncts to trabeculectomy on IOP control in eyes with glaucoma compared to standard trabeculectomy.
SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search was August 2021.
SELECTION CRITERIA: We included randomized controlled trials in participants with glaucoma comparing device-modified trabeculectomy techniques with standard trabeculectomy. We included studies that used antimetabolites in either or both treatment groups.
DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. change in IOP and 2. mean postoperative IOP at one year. Our secondary outcomes were 3. mean change in IOP from baseline, 4. mean postoperative IOP at any time point, 5. mean best-corrected visual acuity (BCVA), 6. visual field change, 7. quality of life, 8. proportion of participants who are drop-free at one year, 9. mean number of IOP lowering medications at one year, and 10. proportion of participants with complications.
MAIN RESULTS: Eight studies met our inclusion criteria, of which seven were full-length journal articles and one was a conference abstract. The eight studies included 961 participants with glaucoma, and compared two types of devices implanted during trabeculectomy versus standard trabeculectomy. Seven studies (462 eyes, 434 participants) used the Ex-PRESS, and one study (527 eyes, 527 participants) used the PreserFlo MicroShunt. No studies using the XEN Gel Stent implantation met our criteria. The studies were conducted in North America, Europe, and Africa. Planned follow-up periods ranged from six months to five years. The studies were reported poorly, which limited our ability to judge risk of bias for many domains. None of the studies explicitly masked outcome assessment. We rated seven studies at high risk of detection bias. Low-certainty of evidence from five studies showed that using the Ex-PRESS plus trabeculectomy compared with standard trabeculectomy may be associated with a slightly lower IOP at one year (mean difference (MD) -1.76 mmHg, 95% confidence interval (CI) -2.81 to -0.70; 213 eyes). Moderate-certainty of evidence from one study showed that using the PreserFlo MicroShunt may be associated with a slightly higher IOP than standard trabeculectomy at one year (MD 3.20 mmHg, 95% CI 2.29 to 4.11). Participants who received standard trabeculectomy may have a higher risk of hypotony compared with those who received device-modified trabeculectomy, but the evidence is uncertain (RR 0.73, 95% CI 0.46 to 1.17; I² = 38%; P = 0.14). In the subgroup of participants who received the PreserFlo MicroShunt, there was a lower risk of developing hypotony or shallow anterior chamber compared with those receiving standard trabeculectomy (RR 0.44, 95% CI 0.25 to 0.79; 526 eyes). Device-modified trabeculectomy may lead to less subsequent cataract surgery within one year (RR 0.46, 95% CI 0.27 to 0.80; I² = 0%).
AUTHORS' CONCLUSIONS: Use of an Ex-PRESS plus trabeculectomy may produce greater IOP reduction at one-year follow-up than standard trabeculectomy; however, due to potential biases and imprecision in effect estimates, the certainty of evidence is low. PreserFlo MicroShunt may be inferior to standard trabeculectomy in lowering IOP. However, PreserFlo MicroShunt may prevent postoperative hypotony and bleb leakage. Overall, device-modified trabeculectomy appears associated with a lower risk of cataract surgery within five years compared with standard trabeculectomy. Due to various limitations in the design and conduct of the included studies, the applicability of this evidence synthesis to other populations or settings is uncertain. Further research is needed to determine the effectiveness and safety of other devices in subgroup populations, such as people with different types of glaucoma, of various races and ethnicity, and with different lens types (e.g. phakic, pseudophakic).
AIM: To systematically review the current evidence based on the efficacy and cost of Ex-PRESS implantation and trabeculectomy (Trab) for uncontrolled glaucoma.
METHODS: Clinical trials were identified by electronic databases (PubMed, EMBASE, ISI Web of science and Cochrane library), and data, such as intraocular pressure (IOP), the complete and qualified success rate, the postoperative complications and the cost, were exacted from these relevant studies. Weighted mean difference (WMD), odds ratio (OR) and 95% confidence intervals (CIs) were calculated and were pooled using a random-effects model.
RESULTS: Eleven relevant publications and two abstracts met the inclusion criteria. The efficacy of Ex-PRESS was similar to that of Trab in the percentage of IOP reduction (IOPR %) at 1, 2y (WMD -2.01; 95% CI: -7.92-3.90; P=0.50 and WMD 2.89; 95% CI: -8.05-13.83; P=0.60, respectively). Ex-PRESS possessed a significant higher complete and qualified success rate (OR: 1.59; 95% CI: 1.07-2.35; P=0.02 and OR: 1.74; 95% CI: 1.06-2.86; P=0.03, respectively). Moreover, Ex-PRESS exerted a significantly lower frequency of hypotony and hyphema than Trab (OR: 0.39; 95% CI: 0.21-0.72; P=0.003 and OR: 0.27; 95% CI: 0.10-0.69; P=0.003, respectively). However, there was no consistent result on the cost between the two groups according to the previous three studies.
CONCLUSION: Both Trab and Ex-PRESS have equivalent efficacy in lowering IOP, yet Ex-PRESS had a lower risk of hypotony and hyphema than Trab. Nevertheless, whether the cost of Ex-PRESS was less than that of Trab should be further investigated to ensure evidence-based conclusion in the long run.
PURPOSE:: To assess the efficacy and safety of trabeculectomy with Ologen implant versus trabeculectomy with mitomycin C (MMC) for treatment of glaucoma.
PATIENTS AND METHODS:: Medline, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar were searched for relevant randomized controlled trials. The outcome measures of efficacy were intraocular pressure and glaucoma medications reductions, and success rate. Safety estimates were measured by relative ratio for complications.
RESULTS:: A total of 6 studies including 224 participants were included in this meta-analysis. Ologen implant was associated with a numerically lower but nonsignificant percentage reduction in IOP compared with MMC. The pooled absolute IOP decreases from baseline (95% confidence interval) were: 13.28 mm Hg (11.33-15.23 mm Hg) versus 15.8 mm Hg (13.21-18.38 mm Hg) at 1 month; 12.95 mm Hg (11.45-14.44 mm Hg) versus 13.87 mm Hg (11.77-15.97 mm Hg) at 3 months; 11.44 mm Hg (8.77-14.11 mm Hg) versus 13.34 mm Hg (11.48-15.20 mm Hg) at 6 months; 10.05 mm Hg (7.14-12.96 mm Hg) versus 11.59 mm Hg (10.27-12.91 mm Hg) at 12 months; and 12.17 mm Hg (8.88-15.47 mm Hg) versus 10.64 mm Hg (8.15-13.12 mm Hg) at 24 months for Ologen implant versus MMC, respectively. There was no significant difference in the reduction in glaucoma medications, success rate, and incidence of complications.
CONCLUSIONS:: Trabeculectomy with an Ologen implant is comparable to the use of MMC with a similar long-term success rate. However, it does not seem to offer significant advantages of avoiding the potential complications related to MMC.
Glaucoma filtration surgery is performed to reduce intraocular pressure (IOP) in patients for whom maximal tolerable pharmacologic IOP-lowering therapy and/or laser surgery fail to lower IOP sufficiently and/or fail to prevent optic nerve damage or visual field deterioration. For decades, the most widely utilized procedure for glaucoma filtration surgery has been trabeculectomy. Although this approach reliably provides long-term IOP reduction in many patients, the postoperative complication rate is high. This has driven the development of alternative approaches to reduce IOP surgically. The EX-PRESS glaucoma filtration device was developed to mimic IOP control by trabeculectomy and to have a better safety profile. This non-valved, medical-grade stainless steel device diverts aqueous humor from the anterior chamber to an intrascleral space. Despite the widespread use of the EX-PRESS device, only a few studies compare its efficacy and safety with that of trabeculectomy. We analyze available data regarding the safety and efficacy of the EX-PRESS device, particularly in comparison with trabeculectomy.
OBJECTIVE: To evaluate the efficacy and safety of Ex-PRESS implantation (Ex-PRESS) compared to trabeculectomy in the treatment of patients with open-angle glaucoma (OAG).
METHODS: A comprehensive literature search using the Cochrane Methodology Register to identify randomized controlled clinical trials (RCCTs) comparing Ex-PRESS to trabeculectomy in patients with OAG. Efficacy estimates were measured by weighted mean difference (WMD) for the percentage intraocular pressure reduction (IOPR%) from baseline to end-point, and odds ratios (OR) for the complete success rate and postoperative interventions. Safety estimates were measured by OR for postoperative complications. Statistical analysis was performed using the RevMan 5.1 software.
RESULTS: A total of four RCCTs were selected for this meta-analysis, including 215 eyes of 200 patients (110 eyes in the Ex-PRESS group, 105 eyes in the trabeculectomy group). There was no significant difference between Ex-PRESS and trabeculectomy in the IOPR% (WMD = 3.15; 95% confidence interval (CI), -6.17-12.47; P = 0.51). The pooled OR comparing Ex-PRESS to trabeculectomy for the complete success rate at one year after surgery were in favor of Ex-PRESS (OR = 2.93; 95% CI, 1.39-6.16; P = 0.005). The Ex-PRESS procedure was found to be associated with lower number of postoperative interventions (OR = 0.23; 95% CI, 0.07-0.81; P = 0.02) and with a significantly lower frequency of hyphema than trabeculectomy (OR = 0.21; 95% CI, 0.05-0.85; P = 0.03), whereas other complications did not differ statistically.
CONCLUSION: In OAG, Ex-PRESS and trabeculectomy provided similar IOP control, but Ex-PRESS was more likely to achieve complete success, with fewer postoperative interventions. Complication rates were similar for the two types of surgery, except for a lower frequency of hyphema in the Ex-PRESS group.
OBJECTIVE: To evaluate the application of the Ologen implant compared to mitomycin C (MMC) on the outcome of trabeculectomy and to examine the balance of risks and benefits.
METHODS: A systematic literature search (Pubmed, Embase, the Cochrane Library, and the Chinese Biomedicine Database) was performed. Randomized controlled trials comparing the Ologen implant with MMC in trabeculectomy were selected. The efficacy measures were the weighted mean differences (WMDs) for the intraocular pressure reduction (IOPR), the reduction in glaucoma medications, and the relative risks (RRs) for success rates. The tolerability measures were RRs for adverse events. The pooled effects were calculated using the random-effects model.
RESULTS: Seven randomized controlled trials including 227 eyes were included in this meta-analysis. The WMDs of the IOPR comparing the Ologen group with the MMC group were -2.98 (95% Cl: -5.07 to -0.89) at one month, -1.41 (-3.72 to 0.91) at three months, -1.69 (-3.68 to 0.30) at six months, -1.94 (-3.88 to 0.01) at 12 months, and 0.65 (-2.17 to 0.47) at 24 months. There was no statistically significance except at one and 12 months after surgery. No significant difference in the reduction in glaucoma medications or complete and qualified success rates were found. The rates of adverse events also did not differ significantly between Ologen and MMC.
CONCLUSIONS: The Ologen implant is comparable with MMC for trabeculectomy in IOP-lowering efficacy, reduction in the number of glaucoma medications, success rates, and tolerability. However, the results should be interpreted cautiously since relevant evidence is still limited, although it is accumulating. Further large-scale, well-designed randomized controlled trials are urgently needed.
PURPOSE: To evaluate the efficacy and safety of EX-PRESS implantation compared with trabeculectomy for uncontrolled open-angle glaucoma.
METHODS: Pertinent randomized controlled trials were identified through systematic searches of the PubMed, EMBASE, and Cochrane Library. The efficacy measures utilized were the weighted mean differences (WMDs) for the intraocular pressure reduction (IOPR), the reduction in glaucoma medications, the change of visual acuity, and the relative risks (RRs) for operative success rates. The safety measures utilized were RRs for postoperative complications. The pooled effects were calculated using the random-effects model.
RESULTS: Four randomized controlled trials of 292 eyes were included in this meta-analysis. The WMDs of the IOPR comparing the EX-PRESS with trabeculectomy were -0.25 (95% Cl: -3.61 to 3.11) at 6 month, 0.053 (-4.31 to 4.42) at 12 months, 0.81 (-4.06 to 5.67) at 24 months, and 0.20 (-2.11 to 2.51) at final follow-up. There was no statistically significance for IOPR at any point after surgery. There were also no significant differences in the reduction in glaucoma medications or visual acuity between the groups. The pooled relative risks comparing EX-PRESS with Trabeculectomy were 1.36 (1.11 to 1.66) for the complete operative success rate and 1.05 (0.94 to 1.17) for the qualified operative success rate. EX-PRESS and Trabeculectomy were associated with similar incidences in most complications with the exception of hyphema, with pooled RR being 0.18 (0.046 to 0.66).
CONCLUSIONS: EX-PRESS implantation and trabeculectomy have similar efficacy in IOP-lowering, medication reduction, vision recovery, and qualified operative success rates. EX-PRESS associated with higher rates of complete operative success and fewer hyphema than with Trabeculectomy. However, these should be interpreted with caution because of the inherent limitations of the included studies.
OBJECTIVE: To evaluate the efficacy and tolerability of Ex-PRESS implantation (Ex-Press) compared with trabeculectomy (Trab) in the treatment of patients with uncontrolled glaucoma.
METHODS: A comprehensive literature meta-analysis was performed according to the Cochrane Collaboration methodology to identify controlled clinical trials comparing Ex-Press with Trab. Efficacy estimates were measured by weight mean difference (WMD) for the percentage intraocular pressure (IOP) reduction from baseline to end-point, odds ratio (OR) for complete success, and qualified success rates. Tolerability estimates were measured by OR for adverse events. All outcomes were reported with a 95% confidence interval (CI). Data were synthesized by Stata 11.0 SE for Windows.
RESULTS: Eight controlled clinical trials meeting the predefined criteria were included in the meta-analysis. A total of 605 eyes from 559 patients with medically uncontrolled glaucoma were included. The weighted mean difference of the percentage IOP reduction from baseline was 2.33 (95% confidence interval: -2.59-7.24) when comparing Ex-Press with Trab. Ex-Press was associated with numerically greater, but nonsignificant, IOP lowering efficacy than Trab. The pooled odds ratio comparing Ex-Press with Trab were 0.93 (0.39, 2.23) for the complete success rate and 1.00 (0.39, 2.56) for the qualified success rate. Ex-Press was associated with a significantly lower frequency of hypotony and hyphema than Trab, with pooled ORs of 0.29 (0.13, 0.65) and 0.36 (0.13, 0.97), respectively.
CONCLUSION: Ex-Press was associated with equivalent efficacy to Trab in lowering IOP. Comparable proportions of patients reached the IOP target with Ex-Press and Trab. Ex-Press was better tolerated than Trab.
Glaucoma is an optic neuropathy that leads to visual field defects and vision loss. It is the second leading cause of irreversible blindness in the world. Treatment for glaucoma aims to reduce intraocular pressure (IOP) to slow or prevent further vision loss. IOP can be lowered with medications, laser, or incisional surgery. Trabeculectomy is a surgical approach which lowers IOP by shunting aqueous humor to a subconjunctival bleb. Device-modified trabeculectomy techniques are intended to improve the durability and safety of this bleb-forming surgery. Trabeculectomy-modifying devices include the Ex-PRESS, the XEN Gel Stent, the PreserFlo MicroShunt, as well as antifibrotic materials such as Ologen, amniotic membrane, expanded polytetrafluoroethylene (ePTFE) membrane, Gelfilm and others. However, the comparative effectiveness and safety of these devices are uncertain.
OBJECTIVES:
To evaluate the benefits and harms of different devices as adjuncts to trabeculectomy on IOP control in eyes with glaucoma compared to standard trabeculectomy.
SEARCH METHODS:
We used standard, extensive Cochrane search methods. The latest search was August 2021.
SELECTION CRITERIA:
We included randomized controlled trials in participants with glaucoma comparing device-modified trabeculectomy techniques with standard trabeculectomy. We included studies that used antimetabolites in either or both treatment groups.
DATA COLLECTION AND ANALYSIS:
We used standard Cochrane methods. Our primary outcomes were 1. change in IOP and 2. mean postoperative IOP at one year. Our secondary outcomes were 3. mean change in IOP from baseline, 4. mean postoperative IOP at any time point, 5. mean best-corrected visual acuity (BCVA), 6. visual field change, 7. quality of life, 8. proportion of participants who are drop-free at one year, 9. mean number of IOP lowering medications at one year, and 10. proportion of participants with complications.
MAIN RESULTS:
Eight studies met our inclusion criteria, of which seven were full-length journal articles and one was a conference abstract. The eight studies included 961 participants with glaucoma, and compared two types of devices implanted during trabeculectomy versus standard trabeculectomy. Seven studies (462 eyes, 434 participants) used the Ex-PRESS, and one study (527 eyes, 527 participants) used the PreserFlo MicroShunt. No studies using the XEN Gel Stent implantation met our criteria. The studies were conducted in North America, Europe, and Africa. Planned follow-up periods ranged from six months to five years. The studies were reported poorly, which limited our ability to judge risk of bias for many domains. None of the studies explicitly masked outcome assessment. We rated seven studies at high risk of detection bias. Low-certainty of evidence from five studies showed that using the Ex-PRESS plus trabeculectomy compared with standard trabeculectomy may be associated with a slightly lower IOP at one year (mean difference (MD) -1.76 mmHg, 95% confidence interval (CI) -2.81 to -0.70; 213 eyes). Moderate-certainty of evidence from one study showed that using the PreserFlo MicroShunt may be associated with a slightly higher IOP than standard trabeculectomy at one year (MD 3.20 mmHg, 95% CI 2.29 to 4.11). Participants who received standard trabeculectomy may have a higher risk of hypotony compared with those who received device-modified trabeculectomy, but the evidence is uncertain (RR 0.73, 95% CI 0.46 to 1.17; I² = 38%; P = 0.14). In the subgroup of participants who received the PreserFlo MicroShunt, there was a lower risk of developing hypotony or shallow anterior chamber compared with those receiving standard trabeculectomy (RR 0.44, 95% CI 0.25 to 0.79; 526 eyes). Device-modified trabeculectomy may lead to less subsequent cataract surgery within one year (RR 0.46, 95% CI 0.27 to 0.80; I² = 0%).
AUTHORS' CONCLUSIONS:
Use of an Ex-PRESS plus trabeculectomy may produce greater IOP reduction at one-year follow-up than standard trabeculectomy; however, due to potential biases and imprecision in effect estimates, the certainty of evidence is low. PreserFlo MicroShunt may be inferior to standard trabeculectomy in lowering IOP. However, PreserFlo MicroShunt may prevent postoperative hypotony and bleb leakage. Overall, device-modified trabeculectomy appears associated with a lower risk of cataract surgery within five years compared with standard trabeculectomy. Due to various limitations in the design and conduct of the included studies, the applicability of this evidence synthesis to other populations or settings is uncertain. Further research is needed to determine the effectiveness and safety of other devices in subgroup populations, such as people with different types of glaucoma, of various races and ethnicity, and with different lens types (e.g. phakic, pseudophakic).
