A Health-Related Quality of Life Measure for Patients Who Undergo Minimally Invasive Glaucoma Surgery.

PURPOSE: To develop a patient-reported outcome measure to assess the impact of glaucoma and treatment, including minimally invasive glaucoma surgery (MIGS). DESIGN: Observational study before and after concomitant cataract and Food and Drug Administration-approved implantable MIGS device surgery. SETTING: Survey administration was on a computer, iPad, or similar device. PATIENT POPULATION: 184 adults completed the baseline survey, 124 a survey 3 months after surgery, and 106 the 1-month test-retest reliability survey. The age range was 37 to 89 (average age = 72). Most were female (57%), non-Hispanic White (81%), and had a college degree (56%). MAIN OUTCOME MEASURES: The Glaucoma Outcomes Survey (GOS) assesses functional limitations (27 items), vision-related symptoms (7 items), psychosocial issues (7 items), and satisfaction with microinvasive glaucoma surgery (1 item). These multiple-item scales were scored on a 0 to 100 range, with a higher score indicating worse health. RESULTS: Internal consistency reliability estimates ranged from 0.75 to 0.93, and 1-month test-retest intraclass correlations ranged from 0.83 to 0.92 for the GOS scales. Product-moment correlations among the scales ranged from 0.56 to 0.60. Improvement in visual acuity in the study eye from baseline to the 3-month follow-up was significantly related to improvements in GOS functional limitations (r = 0.18, P = .0485), vision-related symptoms (r = 0.19, P = .0386), and psychosocial concerns (r = 0.18, P = .0503). Responders to treatment ranged from 17% for vision-related symptoms to 48% for functional limitations. CONCLUSIONS: This study supports using the GOS for ophthalmic procedures such as MIGS. Further evaluation of the GOS in different patient subgroups and clinical settings is needed.

New Devices in Glaucoma.

Glaucoma remains a leading cause of blindness globally. Minimally invasive treatment techniques are rapidly expanding the availability of therapeutic options for glaucoma. These include devices aimed at enhancing outflow through the subconjunctival space, Schlemm's canal, and suprachoroidal space, sustained-release drug delivery devices, and extraocular devices aiming to reduce glaucomatous progression through other novel means. In this review, we provide an overview of several novel devices either newly available or in development for the medical and surgical management of glaucoma. Further studies are required to determine the long-term efficacy of these devices and how they will integrate into the current landscape of glaucoma management.

Device-modified trabeculectomy for glaucoma.

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).

Minimally Invasive Glaucoma Surgical Techniques for Open-Angle Glaucoma: An Overview of Cochrane Systematic Reviews and Network Meta-analysis.

IMPORTANCE: Glaucoma affects more than 75 million people worldwide. Intraocular pressure (IOP)-lowering surgery is an important treatment for this disease. Interest in reducing surgical morbidity has led to the introduction of minimally invasive glaucoma surgeries (MIGS). Understanding the comparative effectiveness and safety of MIGS is necessary for clinicians and patients. OBJECTIVE: To summarize data from randomized clinical trials of MIGS for open-angle glaucoma, which were evaluated in a suite of Cochrane reviews. DATA SOURCES: The Cochrane Database of Systematic Reviews including studies published before June 1, 2021. STUDY SELECTION: Reviews of randomized clinical trials comparing MIGS with cataract extraction alone, other MIGS, traditional glaucoma surgery, laser trabeculoplasty, or medical therapy. DATA EXTRACTION AND SYNTHESIS: Data were extracted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines by one investigator and confirmed by a second. Methodologic rigor was assessed using the AMSTAR 2 appraisal tool and random-effects network meta-analyses were conducted. MAIN OUTCOMES AND MEASURES: The proportion of participants who did not need to use medication to reduce intraocular pressure (IOP) postsurgery (drop-free). Outcomes were analyzed at short-term (<6 months), medium-term (6-18 months), and long-term (>18 months) follow-up. RESULTS: Six eligible Cochrane reviews were identified discussing trabecular bypass with iStent or Hydrus microstents, ab interno trabeculotomy with Trabectome, subconjunctival and supraciliary drainage devices, and endoscopic cyclophotocoagulation. Moderate certainty evidence indicated that adding a Hydrus safely improved the likelihood of drop-free glaucoma control at medium-term (relative risk [RR], 1.6; 95% CI, 1.4 to 1.8) and long-term (RR, 1.6; 95% CI, 1.4 to 1.9) follow-up and conferred 2.0-mm Hg (95% CI, -2.7 to -1.3 mm Hg) greater IOP reduction at long-term follow-up, compared with cataract surgery alone. Adding an iStent also safely improved drop-free disease control compared with cataract surgery alone (RR, 1.4; 95% CI, 1.2 to 1.6), but the short-term IOP-lowering effect of the iStent was not sustained. Addition of a CyPass microstent improved drop-free glaucoma control compared with cataract surgery alone (RR, 1.3; 95% CI, 1.1 to 1.5) but was associated with an increased risk of vraision loss. Network meta-analyses supported the direction and magnitude of these results. CONCLUSIONS AND RELEVANCE: Based on data synthesized in Cochrane reviews, some MIGS may afford patients with glaucoma greater drop-free disease control than cataract surgery alone. Among the products currently available, randomized clinical trial data associate the Hydrus with greater drop-free glaucoma control and IOP lowering than the iStent; however, these effect sizes were small.

Comparison of Patient-Reported Functional Recovery From Different Types of Ophthalmic Surgery.

PURPOSE: To characterize and compare patient-reported recovery of function after cataract or glaucoma surgery using a novel visual analog scale. DESIGN: Prospective observational cohort study. METHODS: Daily for 2 weeks and weekly thereafter, patients recovering from trabeculectomy, tube shunt implantation, or cataract extraction (CE) completed a diary-style questionnaire including visual analog scales (VASs; scored 0-100) grading pain and global function. Clinical examination data and medical histories were collected. Generalized estimating equation models evaluated associations between VAS function scores and pain or visual acuity (VA) and compared scores between surgery types. RESULTS: Among 51 participants followed for 12 weeks, tube shunt placement reduced postoperative day 1 (POD1) function by 47 of 100 points vs CE (P = .006), while trabeculectomy did not reduce POD1 function vs CE (P = .33). After CE, trabeculectomy, and tube shunt placement, average VAS function scores increased 13.94 per week for 2 weeks (P < .001), 4.18 per week for 4 weeks (P = .02), and 7.76 per week for 7 weeks (P < .001), respectively. After those timepoints, there was no further significant change. Beyond 2 weeks, pain levels plateaued, and VA returned to baseline across surgery types; function was inversely related to pain or VA only for the first 2 or 4 weeks, respectively. CONCLUSIONS: Patients recovering from cataract and glaucoma surgery report reduced function in the postoperative period. Tube shunt implantation causes greater morbidity than trabeculectomy, and both are associated with slower improvement than CE. Early postoperative function is associated with VA and pain, but neither fully explains reported impairment. A VAS for function may efficiently capture postoperative recovery.

Priorities and Treatment Preferences among Surgery-Naive Patients with Moderate to Severe Open-Angle Glaucoma.

PURPOSE: To explore patients' perspectives and experiences living with moderate to severe glaucoma through qualitative, semistructured interviews and to identify important benefits and risks that patients consider when choosing glaucoma treatments. DESIGN: Semistructured, in-person qualitative interviews with a convenience sample of patients seen at the Johns Hopkins Wilmer Eye Institute. PARTICIPANTS: Surgery-naive patients 21 years of age or older with moderate to severe open-angle glaucoma seeking treatment at the Wilmer Eye Institute's Glaucoma Center of Excellence between August and December 2018. METHODS: We conducted semistructured interviews with patients diagnosed with moderate to severe open-angle glaucoma, focusing on outcomes they prioritize when considering various treatment options. We used Atlas.ti software version 7.5.12 (Scientific Software Development GmbH, Berlin, Germany) to process interview transcripts and the framework approach to analyze the qualitative data. MAIN OUTCOME MEASURES: Patients' descriptions of outcomes important to them in management of moderate to severe open-angle glaucoma. RESULTS: Thirteen men and 15 women with a median age 67 years participated in the study. Compared with the mild-to-moderate glaucoma patients interviewed previously, these participants similarly emphasized (1) activities of daily living, (2) visual symptoms, (3) treatment burden, and (4) intraocular pressure (IOP) control, but unlike patients with milder disease, most related IOP control directly to (5) avoiding disease progression. Almost all (27/28) had also given significant thought to (6) surgical decision making and could describe how they would decide for or against a particular procedure. Finally, two thirds (18/28) expressed (7) significant fear and worry related to their glaucoma diagnosis. CONCLUSIONS: We identified outcomes that matter to patients who are undergoing treatment for moderate to severe glaucoma, many of which may serve as end points in clinical trials, such as functional independence in vision-dependent activities of daily living, avoidance of visual symptoms, and disease progression via maintenance of IOP control. We also observed that these patients have varied and nuanced perspectives on surgical management and its outcomes. It behooves providers and trial designers to consider these in future evaluations of new treatments for moderate to severe glaucoma.

Ab interno trabecular bypass surgery with iStent for open-angle glaucoma.

BACKGROUND: Glaucoma is a leading cause of irreversible blindness worldwide. In early stages, glaucoma results in progressive loss of peripheral (side) vision; in later stages, it results in loss of central vision leading to blindness. Elevated intraocular pressure (IOP) is the only known modifiable risk factor for glaucoma. Minimally invasive glaucoma surgical (MIGS) techniques, such as ab interno trabecular bypass surgery with iStent (Glaukos Corporation, Laguna Hills, CA, USA), have been introduced as a new treatment modality for glaucoma. However, the effectiveness of MIGS on keeping people 'drop-free' (i.e. not having to use eye drops to control IOP) and other outcomes is uncertain. OBJECTIVES: To assess the effectiveness and safety of ab interno trabecular bypass surgery with iStent (or iStent inject) for open-angle glaucoma in comparison to conventional medical, laser, or surgical treatment. SEARCH METHODS: Cochrane Eyes and Vision's Information Specialist searched the following databases on 17 August 2018: the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register; 2018, Issue 7), MEDLINE Ovid, Embase Ovid, the ISRCTN registry, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We applied no date or language restrictions. We searched the reference lists of reports from included studies. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that had compared iStent or iStent inject to medical therapy, laser treatment, conventional glaucoma surgery (trabeculectomy), or other MIGS procedures. We included RCTs that had compared iStent or iStent inject in combination with phacoemulsification to phacoemulsification alone. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Two review authors independently screened search results, assessed risk of bias, and extracted data from reports of included RCTs using an electronic data collection form. MAIN RESULTS: We included seven RCTs (765 eyes of 764 participants; range per study 33 to 239 participants) that evaluated iStent in people with open-angle glaucoma. We also identified 13 studies that are ongoing or awaiting publications of results. Most participants in the included studies were women (417/764 (55%) participants) and older age (age range: 49 to 89 years). We assessed most trials at unclear or high risk of bias: four trials did not clearly report the method of generating the random sequence or concealing allocation; five were unmasked, open-label studies, which we assessed at high risk of bias for performance and detection bias. All seven trials were funded by the Glaukos Corporation. We graded the certainty of evidence as very low.Four RCTs compared iStent in combination with phacoemulsification to phacoemulsification alone. The summary estimate which we derived from two of the four RCTs suggested that participants in the iStent in combination with phacoemulsification group were 1.38 times more likely to be drop-free between six and 18 months than those in the phacoemulsification alone group (risk ratio (RR) 1.38, 95% confidence interval (CI) 1.18 to 1.63, I2 = 67%). Data from two RCTs also suggested that iStent in combination with phacoemulsification compared to phacoemulsification alone may have offered a small reduction in number of IOP-lowering drops (mean difference (MD) -0.42 drops, 95% CI -0.60 to -0.23). It is uncertain whether there was any difference in terms of mean reduction in IOP from baseline (no meta-analysis).Two RCTs compared treatment with iStent to medical therapy; one of the two trials used the iStent inject. We determined the two trials to be clinically and methodologically heterogeneous and did not conduct a meta-analysis; however, the investigators of both trials reported that over 90% of participants in the treatment groups were drop-free compared to no participants in the medical therapy groups at six to 18 months.One RCT compared treatment with one versus two versus three iStents. There was no difference in terms of participants who were drop-free at 36 months or less; however, at longer follow-up (i.e. at 42 months) participants in the one iStent treatment were less likely to be drop-free than those in the two iStent (RR 0.51, 95% CI 0.34 to 0.75) or three iStent (RR 0.49, 95% CI 0.34 to 0.73) treatment groups. The study did not report the mean change in number of IOP-lowering drops.The type and timing of complications reported varied by RCTs. Similar proportions of participants who underwent treatment with iStent in combination with phacoemulsification and who underwent phacoemulsification alone needed secondary glaucoma surgery. None of RCTs reported findings related to quality of life. AUTHORS' CONCLUSIONS: There is very low-quality evidence that treatment with iStent may result in higher proportions of participants who are drop-free or achieving better IOP control, in the short, medium, or long-term. Results from the 13 studies with results not yet available may clarify the benefits of treatment of people with iStent. Additionally, future MIGS studies should consider measuring quality of life and outcomes that reflect people's ability to perform vision-dependent activities.

Cyclodestructive procedures for non-refractory glaucoma.

BACKGROUND: Glaucoma is a leading cause of blindness worldwide. It results in a progressive loss of peripheral vision and, in late stages, loss of central vision leading to blindness. Early treatment of glaucoma aims to prevent or delay vision loss. Elevated intraocular pressure (IOP) is the main causal modifiable risk factor for glaucoma. Aqueous outflow obstruction is the main cause of IOP elevation, which can be mitigated either by increasing outflow or reducing aqueous humor production. Cyclodestructive procedures use various methods to target and destroy the ciliary body epithelium, the site of aqueous humor production, thereby lowering IOP. The most common approach is laser cyclophotocoagulation. OBJECTIVES: To assess the effectiveness and safety of cyclodestructive procedures for the management of non-refractory glaucoma (i.e. glaucoma in an eye that has not undergone incisional glaucoma surgery). We also aimed to compare the effect of different routes of administration, laser delivery instruments, and parameters of cyclophotocoagulation with respect to IOP control, visual acuity, pain control, and adverse events. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 8); Ovid MEDLINE; Embase.com; LILACS; the metaRegister of Controlled Trials (mRCT) and ClinicalTrials.gov. The date of the search was 7 August 2017. We also searched the reference lists of reports from included studies. SELECTION CRITERIA: We included randomized controlled trials of participants who had undergone cyclodestruction as a primary treatment for glaucoma. We included only head-to-head trials that had compared cyclophotocoagulation to other procedural interventions, or compared cyclophotocoagulation using different types of lasers, delivery methods, parameters, or a combination of these factors. DATA COLLECTION AND ANALYSIS: Two review authors independently screened search results, assessed risks of bias, extracted data, and graded the certainty of the evidence in accordance with Cochrane standards. MAIN RESULTS: We included one trial (92 eyes of 92 participants) that evaluated the efficacy of diode transscleral cyclophotocoagulation (TSCPC) as primary surgical therapy. We identified no other eligible ongoing or completed trial. The included trial compared low-energy versus high-energy TSCPC in eyes with primary open-angle glaucoma. The trial was conducted in Ghana and had a mean follow-up period of 13.2 months post-treatment. In this trial, low-energy TSCPC was defined as 45.0 J delivered, high-energy as 65.5 J delivered; it is worth noting that other trials have defined high- and low-energy TSCPC differently. We assessed this trial to have had low risk of selection bias and reporting bias, unclear risk of performance bias, and high risk of detection bias and attrition bias. Trial authors excluded 13 participants with missing follow-up data; the analyses therefore included 40 (85%) of 47 participants in the low-energy group and 39 (87%) of 45 participants in the high-energy group.Control of IOP, defined as a decrease in IOP by 20% from baseline value, was achieved in 47% of eyes, at similar rates in the low-energy group and the high-energy groups; the small study size creates uncertainty about the significance of the difference, if any, between energy settings (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.64 to 1.65; 79 participants; low-certainty evidence). The difference in effect between energy settings based on mean decrease in IOP, if any exists, also was uncertain (mean difference (MD) -0.50 mmHg, 95% CI -5.79 to 4.79; 79 participants; low-certainty evidence).Decreased vision was defined as the proportion of participants with a decrease of 2 or more lines on the Snellen chart or one or more categories of visual acuity when unable to read the eye chart. Twenty-three percent of eyes had a decrease in vision. The size of any difference between the low-energy group and the high-energy group was uncertain (RR 1.22, 95% CI 0.54 to 2.76; 79 participants; low-certainty evidence). Data were not available for mean visual acuity and proportion of participants with vision change defined as greater than 1 line on the Snellen chart.The difference in the mean number of glaucoma medications used after cyclophotocoagulation was similar when comparing treatment groups (MD 0.10, 95% CI -0.43 to 0.63; 79 participants; moderate-certainty evidence). Twenty percent of eyes were retreated; the estimated effect of energy settings on the need for retreatment was inconclusive (RR 0.76, 95% CI 0.31 to 1.84; 79 participants; low-certainty evidence). No data for visual field, cost effectiveness, or quality-of-life outcomes were reported by the trial investigators.Adverse events were reported for the total study population, rather than by treatment group. The trial authors stated that most participants reported mild to moderate pain after the procedure, and many had transient conjunctival burns (percentages not reported). Severe iritis occurred in two eyes and hyphema occurred in three eyes. No instances of hypotony or phthisis bulbi were reported. The only adverse outcome that was reported by the treatment group was atonic pupil (RR 0.89 in the low-energy group, 95% CI 0.47 to 1.68; 92 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: There is insufficient evidence to evaluate the relative effectiveness and safety of cyclodestructive procedures for the primary procedural management of non-refractory glaucoma. Results from the one included trial did not compare cyclophotocoagulation to other procedural interventions and yielded uncertainty about any difference in outcomes when comparing low-energy versus high-energy diode TSCPC. Overall, the effect of laser treatment on IOP control was modest and the number of eyes experiencing vision loss was limited. More research is needed specific to the management of non-refractory glaucoma.

The Short-term Effect of Subtenon Sponge Application Versus Subtenon Irrigation of Mitomycin-C on the Outcomes of Trabeculectomy With Ex-PRESS Glaucoma Filtration Device: A Randomized Trial.

PURPOSE: Traditionally, during trabeculectomy, Mitomycin-C (MMC) is applied to the tissues using surgical sponges. However, alternate modes of application exist. This study assessed the success rates, complication rates, final intraocular pressure (IOP), and bleb characteristics between patients receiving subtenon MMC application by sponge versus irrigation. PATIENTS AND METHODS: A total of 100 patients with glaucoma were enrolled and each was randomized to 1 of the 2 treatment groups. Patients underwent trabeculectomy with Ex-PRESS shunt and MMC placement and were followed for 6 months. Complication rates assessed included bleb failure, bleb leaks, bleb encapsulation, and hypotony, amongst others. Additional factors evaluated included bleb morphology, glaucoma drop usage, Fluorouracil (5-FU) application, bleb revision, and subsequent glaucoma surgery. RESULTS: The irrigation method provided greater IOP lowering effects (P=0.03); correspondingly the irrigation group had higher rates of hypotony (P=0.03) but with no significant consequences. Patients who had trabeculectomy/Ex-PRESS alone had greater IOP reduction than those who had concurrent cataract surgery (P<0.001). The sponge group had higher rates of 5-FU use (P=0.007) and higher reoperation rates (P=0.02) when compared with the irrigation group. Success was defined as achieving 4 mm Hg≤IOP≤15 mm Hg without any anatomical bleb failure or subsequent glaucoma surgery. The overall success rate was 87%. CONCLUSIONS: Application of subtenon MMC by irrigation seems to provide improved short-term outcomes compared with application with sponges. With a similar safety profile, the irrigation method provides better IOP control, and decreases the need for further clinical/surgical intervention in the short-term after trabeculectomy. Longer-term studies will be useful in analyzing if these differences persist with time.