Long-term survival of Molteno glaucoma drainage devices

The effects of the first versus second glaucoma drainage implant surgery in patients with primary open-angle glaucoma

BACKGROUND

To investigate the outcome of non-valved glaucoma drainage implant surgery (GDIS) in primary open-angle glaucoma (POAG) patients divided in the first GDI group (patients who underwent the first GDIS) and the second GDI group (patients who underwent the second GDIS because of the failed first GDIS).

METHODS

Intraocular pressure (IOP), visual acuity (VA), visual field defect (VFD), medication score (MS), survival rate of GDIS, complications, and patient background was retrospectively analyzed. Two success criteria were set: Criteria (1) IOP reduction ≥ 20% and 5 < IOP ≤ 21, Criteria (2) IOP reduction ≥ 20% and 5 < IOP ≤ 14.

RESULTS

There were 136 eyes of 109 patients in the first GDI group and 32 eyes of 27 patients in the second GDI group. In the first GDI group and II, mean preoperative IOP was 26.7 ± 6.7 mmHg and 23.7 ± 3.5 mmHg, respectively (P = 0.09). No statistically significant difference in postoperative IOP reduction was found between the two groups (P = 0.39). At 5-years postoperative, the Criteria 1 (Criteria 2) survival rate in the first GDI group and the second GDI group was 60.4% (31.7%) and 61.2% (25.6%), respectively (Criteria 1: hazard ratio [HR]: 0.64, 95% confidence interval [CI]: 0.30-1.35 [P = 0.24]; Criteria 2: HR: 0.81, 95% CI: 0.46-1.44, P = 0.48). No significant difference in VA, VFD change, MS, or complications was observed. Young patient age was the only significant factor for failure in the first GDI group (odds ratio: 0.95, 95% confidence interval: 0.91-1.00, P = 0.03).

CONCLUSION

The second GDIS may be as effective as the first GDIS for IOP reduction in POAG patients, however, there is a high risk of failure in young-age patients and the surgery may be ineffective in eyes requiring Criteria 2.

Outcomes of Glaucoma Reoperations in the Primary Tube Versus Trabeculectomy Study

PURPOSE

To describe the incidence and outcomes of reoperations for glaucoma in the Primary Tube Versus Trabeculectomy (PTVT) Study.

DESIGN

Cohort study of patients in a multicenter randomized clinical trial.

PARTICIPANTS

The PTVT Study enrolled 242 patients with medically uncontrolled glaucoma and no previous incisional ocular surgery.

METHODS

Randomization assigned 125 patients to placement of a tube shunt (350-mm2 Baerveldt glaucoma implant) and 117 patients to trabeculectomy with mitomycin C (MMC, 0.4 mg/ml for 2 minutes). Data were analyzed from patients who underwent additional glaucoma surgery.

MAIN OUTCOME MEASURES

Outcome measures included intraocular pressure (IOP), use of glaucoma medications, visual acuity, surgical complications, and failure (IOP > 21 mmHg or reduced by <20%, IOP ≤ 5 mmHg, additional glaucoma surgery, or loss of light perception vision).

RESULTS

Additional glaucoma surgery was performed in 21 patients in the tube group and 12 patients in the trabeculectomy group in the PTVT Study, and the 5-year cumulative reoperation rate for glaucoma was 18.0% in the tube group and 10.4% in the trabeculectomy group (P = 0.15). Follow-up (mean ± standard deviation [SD]) after additional glaucoma surgery was 35.1 ± 17.7 months in the tube group and 30.1 ± 17.6 months in the trabeculectomy group (P = 0.44). At 3 years after glaucoma reoperation, IOP (mean ± SD) was 15.5 ± 4.8 mmHg in the tube group and 16.6 ± 7.3 mmHg in the trabeculectomy group (P = 0.71). The number of glaucoma medications (mean ± SD) after 3 years of follow-up was 2.1 ± 1.7 in the tube group and 1.7 ± 1.0 in the trabeculectomy group (P = 0.58). The cumulative probability of failure at 3 years after a glaucoma reoperation was 37.8% in the tube group and 21.3% in the trabeculectomy group (P = 0.47).

CONCLUSION

No significant difference in the rate of reoperation for glaucoma was observed after tube shunt implantation and trabeculectomy with MMC in the PTVT Study. Similar surgical outcomes were observed after additional glaucoma surgery, irrespective of the initial procedure to which the patient was randomized.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Ahmed Glaucoma Valve Implantation to Reduce Intraocular Pressure: Updated Perspectives

Trabeculectomy and glaucoma drainage device implantation are the most commonly performed glaucoma surgeries worldwide. Although trabeculectomy is the gold standard, at the present time there is an increase in the use of glaucoma drainage devices. The Ahmed glaucoma valve is one of the most widely used glaucoma drainage devices worldwide. Corneal endothelial cell loss and eventually corneal decompensation is one of the serious complication of glaucoma drainage device implantation. To avoid this, drainage tube can be inserted into the ciliary sulcus instead of the anterior chamber, especially in eyes with high risk for corneal decompensation. Tube/plate exposure, hypertensive phase, endophthalmitis, cataract formation, diplopia and ocular hypotony are the other potential complications that can develop after Ahmed glaucoma valve implantation.

Comparing Ahmed-FP7 to Baerveldt-250 and Baerveldt-350 surgical outcomes: 1-year results from a retrospective cohort study leveraging the electronic health record

OBJECTIVE

To compare outcomes following Ahmed-FP7 (AGI-FP7), Baerveldt-250mm2 (BGI-250), or Baerveldt-350mm2 (BGI-350) implantation.

METHODS AND ANALYSIS

Retrospective cohort study comprising 800 eyes from 800 individuals who underwent surgery 1 January 2016-31 December 2020 at a tertiary-care institution. Data were extracted from standardised fields in the electronic health record. Primary outcome was failure (defined as intraocular pressure (IOP) ≤5 mm Hg or >18 mm Hg or reduction <20% at two consecutive visits from month 3 onwards; or visual acuity (VA) loss ≥3 lines; or return to the operating room (OR)). Secondary outcomes were IOP, VA, number of follow-up visits and return to the OR.

RESULTS

A total of 523 AGI-FP7, 133 BGI-250 and 144 BGI-350 cases were analysed. The AGI-FP7 group was more likely to be younger and diagnosed with secondary glaucoma, with a higher mean baseline IOP (28.5±12.2 vs 22.0±7.7 mm Hg in BGI-250 and 23.4±9.0 in BGI-350, p<0.001). Cumulative failure rate at month 12 was 30% (AGI-FP7) vs 39% (BGI-250) vs 33% (BGI-350, p=0.159). Mean IOP at month 12 was lower in the BGI-350 group compared with AGI-FP7 (12.4±4.4 vs 14.8±5.6 mm Hg, p=0.003) but not BGI-250 (vs 13.1±4.6, p=0.710). Target IOP was achieved in 71% of AGI-FP7, 66% BGI-250, and 76% BGI-350. VA loss and rates of return to the OR did not differ between groups. Both BGI-250 and BGI-350 had more follow-up visits than AGI-FP7 (p<0.001).

CONCLUSION

These three glaucoma drainage devices performed similarly within 1 year, with no difference in failure rates despite differing baseline patient characteristics.

Development of a Novel Valve-Controlled Drug-Elutable Microstent for Microinvasive Glaucoma Surgery: In Vitro and Preclinical In Vivo Studies

Purpose

Microinvasive glaucoma surgery (MIGS) has become an important treatment approach for primary open-angle glaucoma, although the safe and long-term effective lowering of intraocular pressure with currently available implants for MIGS is not yet achieved to a satisfactory extent. The study focusses on the development and in vitro and in vivo testing of a novel microstent for MIGS.

Methods

A silicone elastomer-based microstent was developed. Implants were manufactured using dip coating, fs-laser cutting, and spray coating. Within the current study no antifibrotic drug was loaded into the device. Sterilized microstents were analyzed in vitro regarding pressure-flow characteristics and biocompatibility. Six New Zealand white rabbits were implanted with a microstent draining the aqueous humor from the anterior chamber into the subconjunctival space. Drainage efficacy was evaluated using oculopressure tonometry as a transient glaucoma model. Noninvasive imaging was performed.

Results

Microstents were manufactured successfully and characterized in vitro. Implantation in vivo was successful for four animals with additional device fixation. Without additional fixation, dislocation of microstents was found in two animals. Safe and effective intraocular pressure reduction was observed for the four eyes with correctly implanted microstent during the 6-month trial period.

Conclusions

The described microstent represents an innovative treatment approach for MIGS. The incorporation of a selectively antifibrotic drug into the microstent drug-elutable coating will be addressed in future investigations.

Translational Relevance

The current preclinical study successfully provided proof of concept for our microstent for MIGS which is suitable for safe and effective intraocular pressure reduction and offers promising perspectives for the clinical management of glaucoma.

Risk Factors for Failure of Tube Shunt Surgery: A Pooled Data Analysis

PURPOSE

To identify the risk factors associated with failure of tube shunt surgery.

DESIGN

Pooled analysis of 3 prospective multicenter, randomized clinical trials.

METHODS

A total of 621 patients with medically uncontrolled glaucoma were enrolled, including 276 from the Ahmed Baerveldt Comparison Study, 238 from the Ahmed Versus Baerveldt Study, and 107 from the tube group of the Tube Versus Trabeculectomy Study. Patients were randomized to treatment with an Ahmed glaucoma valve (model FP7) or Baerveldt glaucoma implant (model 101-350). The associations between baseline risk factors and tube shunt failure were assessed using a Cox proportional hazards regression model. The primary outcome measure was the rate of surgical failure defined as intraocular pressure (IOP) > 21 mmHg or reduced < 20% from baseline, IOP ≤ 5 mmHg, loss of light perception vision, reoperation for glaucoma, or removal of implant.

RESULTS

The cumulative probability of failure after tube shunt surgery was 38.3% after 5 years. In multivariable analyses, baseline factors that predicted tube shunt failure included preoperative IOP (≤ 21 mmHg compared to IOP > 21 and ≤ 25 mmHg; HR, 2.34; 95% CI, 1.52-3.61; P < .001), neovascular glaucoma (HR, 1.79; 95% CI, 1.28-2.52; P = .001), randomized treatment (for Ahmed glaucoma valve; HR, 1.36; 95% CI, 1.04-1.78; P = .025), and age (for 10 year decrease in age; HR, 1.19; 95% CI, 1.09-1.31; P < .001).

CONCLUSIONS

Lower preoperative IOP, neovascular glaucoma, Ahmed implantation, and younger age were predictors of tube shunt failure. This Study provides the largest prospectively collected dataset on tube shunt surgery.

Management of Childhood Glaucoma Following Cataract Surgery

Glaucoma remains a frequent serious complication following cataract surgery in children. The optimal approach to management for 'glaucoma following cataract surgery' (GFCS), one of the paediatric glaucoma subtypes, is an ongoing debate. This review evaluates the various management options available and aims to propose a clinical management strategy for GFCS cases. A literature search was conducted in four large databases (Cochrane, PubMed, Embase, and Web of Science), from 1995 up to December 2021. Thirty-nine studies-presenting (1) eyes with GFCS; a disease entity as defined by the Childhood Glaucoma Research Network Classification, (2) data on treatment outcomes, and (3) follow-up data of at least 6 months-were included. Included papers report on GFCS treated with angle surgery, trabeculectomy, glaucoma drainage device implantation (GDD), and cyclodestructive procedures. Medical therapy is the first-line treatment in GFCS, possibly to bridge time to surgery. Multiple surgical procedures are often required to adequately control GFCS. Angle surgery (360 degree) may be considered before proceeding to GDD implantation, since this technique offers good results and is less invasive. Literature suggests that GDD implantation gives the best chance for long-term IOP control in childhood GFCS and some studies put this technique forward as a good choice for primary surgery. Cyclodestruction seems to be effective in some cases with uncontrolled IOP. Trabeculectomy should be avoided, especially in children under the age of one year and children that are left aphakic. The authors provide a flowchart to guide the management of individual GFCS cases.

The influence of etiology on surgical outcomes in neovascular glaucoma

Background

The authors sought to evaluate visual outcomes in patients with varying etiologies of neovascular glaucoma (NVG), who were treated with glaucoma drainage devices (GDD).

Methods

This was a retrospective case series of patients at a large academic teaching institution who had surgical intervention for neovascular glaucoma between September 2011 and May 2019. Eyes were included if there was documented neovascularization of the iris/angle with an intraocular pressure (IOP) > 21 mmHg at presentation. Eyes must also have been treated with surgical intervention that included a GDD. Primary outcome measure was visual acuity at the 1-year post-operative visit. Secondary outcome measure was qualified success after surgery defined by: pressure criteria (5 mmHg < IOP ≤ 21 mmHg), no re-operation for elevated IOP, and no loss of LP vision.

Results

One hundred twenty eyes met inclusion criteria. 61.7% had an etiology of proliferative diabetic retinopathy (PDR), 23.3% had retinal vein occlusions (RVO), and the remaining 15.0% suffered from other etiologies. Of patients treated with GDD, eyes with PDR had better vision compared to eyes with RVO at final evaluation (p = 0.041). There was a statistically significant difference (p = 0.027) in the mean number of glaucoma medications with Ahmed eyes (n = 70) requiring 1.9 medications and Baerveldt eyes (n = 46) requiring 1.3 medications at final evaluation.

Conclusions

In our study, many patients with NVG achieved meaningful vision, as defined by World Health Organization (WHO) guidelines, and IOP control after GDD. Outcomes differed between patients with PDR and RVO in favor of the PDR group. Different GDD devices had similar performance profiles for VA and IOP outcomes. Direct prospective comparison of Baerveldt, Ahmed, and cyclophotocoagulation represents the next phase of discovery.

Comparison of Outcomes Following Glaucoma Drainage Tube Surgery Between Primary and Secondary Glaucomas, and Between Phakic and Pseudophakic eyes

PURPOSE

To report outcomes of glaucoma drainage device (GDD) surgery based on primary or secondary glaucoma diagnosis and lens status.

DESIGN

Single-center, retrospective, consecutive cohort study.

METHODS

University of Florida patients aged 18 to 93 years who underwent nonvalved GDD surgery between 1996 and 2015 with a minimum of 1-year follow-up were examined. Of the 186 eyes of 186 patients enrolled, 108 had a primary glaucoma and 78 a secondary glaucoma diagnosis. Excluding 13 aphakic patients, 57 eyes were phakic and 116 pseudophakic. Mean intraocular pressure (IOP), mean number of medications, visual acuity (VA), surgical complications, and failure (IOP ≥18 mm Hg, IOP <6 mm Hg, reoperation for glaucoma, or loss of light perception) were the main outcome measures.

RESULTS

No significant difference was noted in mean IOP and mean medication use (12.8 ± 4.5 and 13.0 ± 6.6 mm Hg on 2.0 ± 1.2 and 1.5 ± 1.1 medication classes, respectively), mean VA (1.08 ± 0.98 and 0.94 ± 0.89, respectively), failure, or numbers of complications and reoperations (P > 0.05) between eyes with primary and secondary glaucomas at up to 5 years postoperatively. Comparison of phakic and pseudophakic eyes showed a statistically significant higher success rate for the pseudophakic patient group at the ≥18 mm Hg upper limit and <6 mm Hg lower limit (P = 0.01), and significantly fewer eyes required reoperation to lower IOP (6.9% vs 23%).

CONCLUSIONS

GDD surgery appears equally effective for secondary glaucomas as for primary glaucomas, and has a better outcome for pseudophakic eyes than phakic eyes.

Evaluation of primary Ahmed Glaucoma valve implantation in post-traumatic angle recession glaucoma in Indian eyes

PURPOSE

To highlight the efficacy of primary Ahmed glaucoma valve implantation in angle recession glaucoma following blunt ocular trauma in Indian eyes.

DESIGN

A retrospective analytical study.

MATERIALS AND METHODS

This study included 52 patients of angle recession glaucoma, who presented between Mar 2006 to Feb 2016, out of which 38 patients had undergone primary AGV implantation, while the rest were managed with topical anti-glaucoma medications. Preoperative data included age, sex, type and mode of injury, duration of injury, assessment of best-corrected visual acuity (BCVA) and intraocular pressure (IOP). The extent of angle recession was observed by gonioscopy. The intraocular pressure, visual acuity, and the number of anti-glaucoma medications were measured postoperatively. The success of this technique was analyzed by using a Kaplan-Meier cumulative survival curve.

RESULTS

Following AGV implantation, the mean IOP was significantly reduced to 8.7 ± 2.2 at 1st day, 10.1 ± 2.2 at 7th day, 14.2 ± 3.4 at 3rd month, 15.6 ± 3.7 at 1 year, and 15.6 ± 3.6 at 3rd-year follow-up showing statistically significant values (p < 0.001) at each visit. The IOP was successfully controlled at the last follow-up without topical treatment. Mean BCVA at 3 years -post-AGV was 0.144 (0.151) (LogMAR) which was statistically significant (p < 0.001) as compared to the mean BCVA of 0.898 (± 0.205) LogMAR units at presentation. The success rate by Kaplan-Meier survival curve analysis was 90% at the mean follow-up duration of 29.47 ± 3.39 months. Overall surgical complications were noted in the form of prolonged hypotony, hyphema in 7 patients (13.5%).

CONCLUSIONS

In medically uncontrolled post-traumatic angle recession glaucoma, primary AGV Implantation is a safe and effective surgical procedure with lesser complication rates providing long-term IOP control in a younger population.

Ahmed glaucoma valve implantation with the tube placement in the ciliary sulcus: short-term results

PURPOSE

To evaluate the clinical outcomes of pseudophakic/aphakic eyes with uncontrolled glaucoma that underwent Ahmed glaucoma valve implantation with the tube placement in the ciliary sulcus.

METHODS

Medical records of the patients who underwent Ahmed glaucoma valve implantation through the ciliary sulcus, between December 2017 and June 2019, were reviewed retrospectively. Patients' age, gender, glaucoma diagnosis, visual acuity, intraocular pressure levels, and complications were recorded.

RESULTS

Forty-seven eyes of 43 patients with glaucoma were enrolled. The mean age was 54.5 ± 19.9 years (range, 7-88 years) at the time of surgery, and the mean postoperative follow-up period was 7.9 ± 3.4 months (range, 3-16 months). The mean preoperative intraocular pressure level was 35.2 ± 6.8 mmHg (range, 25-55 mmHg), and it was found as 15.6 ± 5.4 mmHg (range, 9-33 mmHg) at the last follow-up visit. Decrease in intraocular pressure level was statistically significant (P < 0.001). At the last follow-up visit, success (postoperative IOP ≥ 6 mmHg and ≤ 21 mmHg with or without antiglaucomatous medications, without further surgery for IOP control, without loss of light perception and without removal of the implant) was achieved in 41 eyes (87.2%). Hyphema was the most common postoperative complication and developed in 11 eyes (23.4%) and resolved spontaneously in all of them within one month.

CONCLUSION

In pseudophakic or aphakic eyes with uncontrolled glaucoma, placement of Ahmed glaucoma valve tube in the ciliary sulcus is a safe and effective procedure. Ciliary sulcus can be considered as a potential space during tube shunt surgery in eyes with high risk of tube-corneal touch or corneal decompensation.

Comparison of Outcomes of Glaucoma Drainage Implant Surgery With or Without Prior Failed Trabeculectomy

PRECIS

A comparison of 186 glaucoma patients with mixed diagnoses who underwent nonvalved glaucoma drainage device (GDD) implant surgery showed similar long-term intraocular pressure (IOP), medication, and visual acuity (VA) outcomes between those with prior failed trabeculectomy surgery versus those without.

PURPOSE

The purpose of this study was to evaluate whether prior failed trabeculectomy adversely affects the outcome of glaucoma tube surgery.

PATIENTS AND METHODS

A total of 186 eyes of 186 patients who underwent a nonvalved GDD implant surgery by a single surgeon between 1996 and 2015 at a University practice were included. Patients were of mixed diagnoses and over 18 years old. Before the GDD surgery, 65 had a previous failed glaucoma filtering surgery and 121 had no prior glaucoma surgery. Demographic information, preoperative and postoperative IOP, medication, VA, and complications were collected from chart review.

RESULTS

No significant difference was noted in mean IOP and mean medication use (13.0 and 12.6 mm Hg on 2.0 and 1.7 medication classes at 5 y postoperatively, respectively), mean VA and change in VA from baseline, or numbers of complications (P>0.05), between eyes that had a prior failed filtration surgery and those that had not. Kaplan-Meier plots for failure over 5 years using a lower limit of <5 mm Hg and an upper limit of ≥18, ≥15, or ≥12 mm Hg did not show a significant difference between groups. Subanalyses were performed to examine only primary glaucoma eyes and results were similar. Further group subanalyses comparing those with baseline IOP ≥25 or <25 mm Hg, age 65 and above or below 65 years and those specifically with Baerveldt 350 mm2 implants also did not show significant differences.

CONCLUSION

Prior failed filtration surgery does not appear to affect the outcome of future GDD surgery.

Surgical Results of Ahmed Glaucoma Valve Implantation in One-chamber Eyes

PRECIS

Ahmed glaucoma valve (AGV) implantation in eyes with damaged iris-lens diaphragms ("1-chamber" eyes) resulted in mean intraocular pressure (IOP) and antiglaucoma medications decreases of 66% and 59% (P<0.0001 for both), respectively, at the mean 23-month follow-up.

PURPOSE

The purpose of this study was to report the results of AGV implantation with pars plana tube insertion to control IOP in glaucomatous eyes with damaged iris-lens diaphragms ("1-chamber" eyes).

METHODS

The medical records of 52 consecutive glaucomatous 1-chamber eyes (48 Japanese patients, mean age±SD, 76.0±11.2 y) were retrospectively reviewed. Other than aphakic eyes, eyes were defined as having 1 chamber if intraocular lenses (IOLs) were sclerally or intrasclerally fixated, IOLs were fixed on-the-bag due to posterior capsular defects, vitreous collapse into the anterior chamber resulted from Zinn zonular dialysis, and phacodonesis or IOL-donesis required lens/IOL explantation during AGV implantation. The data collected were preoperative/postoperative IOPs, numbers of antiglaucoma medications, visual acuity, anterior chamber flare, visual field mean deviation, corneal endothelial cell density, and surgical complications/interventions.

RESULTS

The preoperative IOP (28.5±9.4 mm Hg) and a number of antiglaucoma medications (3.2±1.2) decreased significantly (P<0.0001 for both) to 9.8±3.3 mm Hg and 1.3±1.3, respectively, at the final visit (mean follow-up, 23 mo). The success rates of IOP control (6 to 21 mm Hg and >20% reduction irrespective of medication use) were 82.5% and 79.0%, respectively, at postoperative years 1 and 2. The most common postoperative complications were macular edema (n=9, 17%), choroidal detachment (n=8, 15%), vitreous hemorrhage (n=7, 13%), and hyphema (n=7, 13%). The most common postoperative intervention was tubal repositioning/reopening (n=6, 12%). Compared with preoperative values, the visual acuity, anterior chamber flare, mean deviation, corneal endothelial cell density remained unchanged postoperatively.

CONCLUSION

Choice of pars plana AGV tube insertion with simultaneous vitrectomy is reasonable to achieve IOP reduction and minimize vision-threatening complication in glaucomatous eyes with a damaged iris-lens diaphragm.

Risk Factors for Failure in Double-Plate Tube Surgery for Refractory Glaucoma: 25 Years Surgical Experience

Purpose

To investigate risk factors associated with success and failure in double-plate tube surgery.

Methods

This retrospective case-series observational study included 243 consecutive eyes that underwent anterior-segment double-plate tube surgery from 1990 to 2015. Evaluation of the efficacy of the device was based on the final intraocular pressure (IOP) and the need for anti-glaucoma medication. We also assessed success and failure according to risk factors for trabeculectomy and an early hypertensive phase (HP).

Results

Preoperative IOP was 37.3±13.1 mmHg (mean±SD) with 3.0±0.7 medications. After a median follow-up of 44.3 months, the mean IOP was 14.6±6.3 mmHg with 0.4±1.0 medications. The final IOPs ranged from 6 to 21 mmHg in 87.24% of eyes; however, 25.47% required medication. No risk factors studied were associated with surgical failure. Preoperative IOP, glaucoma type, previous surgery, previous anti-glaucoma drugs, implant type, and HP were associated with partial success (p<0.05). HP and preoperative use of brimonidine reduced the probability of complete success by 66.9% and 68.2%, respectively (p<0.05). HP was more likely when chronic preoperative prostaglandin analogues were administered (odds ratio [OR] 4.286; 95% confidence intervals [CI] 1.593–11.529; P=0.0039) and when the tube was located in the posterior chamber (OR 3.561; 95% CI 1.286–9.861; P=0.0145).

Conclusion

Tube surgery is effective and seems to be independent of the major risk factors for glaucoma surgery. However, previous surgery and some chronic preoperative drugs are related to the need for glaucoma medication to achieve the target pressure.

Efficacy and Safety of the Susanna Glaucoma Drainage Device After 1 Year of Follow-up

PRECIS

This study found a rate of failure of 13.6% of the new Susanna Glaucoma Drainage Device (SGDD) after 1 year of follow-up. Severe complications occurred in 1 patient (4.5%).

PURPOSE

The purpose of this study was to determine the success and complications rates of the SGDD implant in refractory glaucoma.

PATIENTS AND METHODS

This is a retrospective study. Medical records from all consecutive refractory glaucoma patients (failed trabeculectomies with the use of adjunctive mitomycin) followed in a private clinical practice were included in the study. All patients had undergone SGDD implant surgery from September 2016 to July 2019 were included. All surgeries were done by the same surgeon (R.S.). Primary outcome was surgical failure, defined as intraocular pressure (IOP) >18 mm Hg and/or <20% IOP reduction from baseline, IOP<5 mm Hg, reoperation for glaucoma, need of implant removal or loss of light perception vision. Secondary outcomes included mean IOP, use of supplemental medical therapy, and complications.

RESULTS

In all, 22 eyes were analyzed. Mean patient age was 63±15 years (range: 27 to 87 y). Mean IOP decreased from 23±7 to 11±8 mm Hg (P<0.001, paired t test) at an average of 18±9 months after the tube implant. The mean SD number of glaucoma medications was reduced from 3.3±1 to 1.5±1.2 at the last postoperative visit (P<0.01, paired t test). No early postoperative complications occurred. There was 1 case of late persistent hypotony in a patient with previous endocyclophotocoagulation that was solved with tube ligature with silk 8-0. Failure because of high IOP occurred in 2 cases. There was no extrusion or erosion of the tube and the plate.

CONCLUSION

The SGDD presented a 13.6% failure rate (86.4% success rate) with very few complications, being an efficient and safe alternative for refractory glaucoma.

Comparative Outcomes of the Molteno3 and Baerveldt Glaucoma Implants

PURPOSE

To compare outcomes between 2 nonvalved glaucoma drainage devices (GDDs) used to treat refractory glaucoma or in patients with neovascular/uveitic glaucoma likely to be poorly responsive to less aggressive therapies.

DESIGN

Retrospective, nonrandomized, multicenter comparative study.

PARTICIPANTS

A total of 117 eyes from 117 patients.

METHODS

Retrospective chart review of patients who underwent implantation of the Baerveldt (BGI) (Abbott Medical Optics, Abbott Park, IL) or the Molteno3 glaucoma implant (MGI) (Molteno Ophthalmic Limited, Dunedin, New Zealand). Noninferiority of the MGI versus the BGI was tested with Cox and mixed-effects regression models. Interventions in each group were analyzed with chi-square tests.

MAIN OUTCOME MEASURES

The primary outcome was time until device failure, defined as intraocular pressure (IOP) >21 mmHg or a reduction <20%, hypotony, reoperation for glaucoma, or loss of light perception. Secondary outcomes were intraoperative time, postoperative IOP, number of IOP-lowering medications, and visual acuity (VA).

RESULTS

The MGI could not be deemed noninferior to the BGI with regard to time until device failure (hazard ratio [HR], 0.83; confidence interval [CI], 0.41-1.65). The MGI was noninferior to the BGI when comparing postoperative IOP, a difference of -0.40 mmHg (95% CI, -1.74-0.93). The MGI needed 2% fewer medications (ratio of 0.98, 95% CI, 0.79-1.22), but noninferiority could not be claimed. With regard to VA, the MGI's mean was 0.10 logarithm of the minimum angle of resolution (logMAR) higher (95% CI, -0.01-0.21), but noninferiority testing was again inconclusive. Intraoperative time for the MGI was 15.7 minutes shorter versus the 350 mm² plate size BGI (P < 0.001) and 4.3 minutes shorter versus the 250 mm² plate size BGI (P = 0.32). More patients in the MGI group needed secondary operative management (11%, P = 0.03).

CONCLUSIONS

The MGI was noninferior to the BGI in lowering IOP. Differences in time until device failure, VA outcomes, and medication use were inconclusive. The MGI required more secondary operative interventions. The MGI required less time to implant than the BGI's 350 mm² plate size implant. Overall, the use of both GDDs is justifiable to lower IOP when more conservative management has failed.

Treatment of Uveitis and Outcomes of Glaucoma Drainage Implant Surgery: A Meta-Analysis

PURPOSE

We performed a meta-analysis to evaluate the effect of uveitis treatment on glaucoma drainage implant surgical outcomes.

METHODS

We included 16 articles in the meta-analysis. Two groups were defined based on medical therapy of uveitis: Group 1: poorly controlled uveitis, and Group 2: well-controlled uveitis including use of immunomodulatory medications.

RESULTS

The two groups were similar in comparisons of follow-up time, age, gender, and etiology of uveitis. Meta-analysis demonstrated significantly greater success in Group 2 (95.1%) compared to Group 1 (81.6%) at 1 year after glaucoma drainage implant surgery (P = .001). The final success was significantly greater (P 0.014) in group 2 compared with group 1 (86.1% and 74.3%, respectively).

CONCLUSION

Surgical success was significantly higher in uveitic glaucoma patients treated with more intensive immunosuppressive therapy before and after glaucoma drainage implant surgery. The level of control of uveitis perioperatively appears to influence glaucoma drainage implant surgery outcomes.

Surgical Outcomes of a Second Ahmed Glaucoma Valve Implant for the Treatment of Refractory Glaucoma

PRéCIS:: In this article, the authors concluded that an additional Ahmed glaucoma valve (AGV) implantation after the failure of an initial AGV, even with the addition of glaucoma medications, maybe a good surgical treatment option for refractory glaucoma.

PURPOSE

To evaluate the surgical outcomes of a second AGV implant in Hispanic patients with refractory glaucoma.

MATERIALS AND METHODS

The medical records of patients who underwent a second AGV implant were reviewed retrospectively. Clinical outcome measures including intraocular pressure (IOP), visual acuity, and glaucoma medication use were collected from the preoperative visit and all follow-up visits up to 18 months after surgery. Failure was defined as one of the following: loss of light perception, sustained IOP >21 or <6 mm Hg, an IOP reduction of <20% from baseline, need for additional glaucoma surgery, including needling revision with subconjunctival adjuvant therapy, or valve extrusion.

RESULTS

A total of 48 patients were included. In all cases, an S-2 model was implanted in the superonasal quadrant. Mean preoperative IOP was 24.3±7.9 mm Hg and was significantly reduced to 13.9±4.8 at 6 months (P<0.05), 15.4±7.2 at 12 months (P<0.05), and 12.9±2.0 at 18 months (P<0.05). Mean glaucoma medications were reduced from 2.8±1.1 preoperatively to 1.9±1.2 at 6 months (P<0.05), 2.4±1.2 at 12 months, and 2.2±1.1 at 18 months; however, the difference was no longer statistically significant after 6 months, and the success rate was 60% at the mean for survival time of 15 months (13.7 to 16.5).

CONCLUSION

The findings of this study demonstrate that a second AGV can achieve a significant reduction in IOP for up to 18 months postoperatively.

Incidence of Conjunctival Exposure following Drainage Device Implantation in Patients with Glaucoma

Purpose

To evaluate prior studies including a glaucoma drainage device and to describe the timing and incidence of conjunctival exposure. A meta-analysis of previously published articles.

Methods

Articles included were prospective, single cohort, or comparative parallel design, with a mean treatment period of at least 3 months and at least 30 patients per treatment arm. We limited our analysis to studies that evaluated the most common devices, including Ahmed, Baerveldt, and Molteno.

Results

We included 38 studies containing 45 treatment arms (16 Ahmed, 12 Baerveldt, and 17 Molteno). These studies included 3,105 patients and 3,255 eyes with an average follow-up of 26.1±3.3 months. The overall incidence of exposure was 2.0±2.6% (n=64) of eyes with an average exposure/month of 0.09±0.14%. There was no significant correlation between study length and incidence of exposure (p=0.11), although multivariate regression analysis identified length of follow-up as a risk factor for exposure (p=0.001). Among individual drainage devices, there was no significant difference in the incidence of exposure (p=0.22) or percent exposure per month (p=0.18). In addition, no difference existed in the incidence of exposure between sizes for the Baerveldt 250, 350 or 500 mm (p=0.7), number of plates for the Molteno Single or Double (p=0.3), nor between the composition of the Ahmed Silicone or Polypropylene (p=0.7).

Conclusions

This study suggests that tube exposure of glaucoma implants is unusual and the incidence does not differ between the Ahmed, Baerveldt, and Molteno implants. However, exposure appears to occur at any time within the first 5 years following implantation.

Aqueous shunts for glaucoma

BACKGROUND

Aqueous shunts are employed to control intraocular pressure (IOP) for people with primary or secondary glaucomas who fail or are not candidates for standard surgery.

OBJECTIVES

To assess the effectiveness and safety of aqueous shunts for reducing IOP in glaucoma compared with standard surgery, another type of aqueous shunt, or modification to the aqueous shunt procedure.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 8), MEDLINE Ovid (1946 to August 2016), Embase.com (1947 to August 2016), PubMed (1948 to August 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to August 2016), ClinicalTrials.gov (www.clinicaltrials.gov); searched 15 August 2016, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 15 August 2016. We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 15 August 2016. We also searched the reference lists of identified trial reports and the Science Citation Index to find additional trials.

SELECTION CRITERIA

We included randomized controlled trials that compared various types of aqueous shunts with standard surgery or to each other in eyes with glaucoma.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results for eligibility, assessed the risk of bias, and extracted data from included trials. We contacted trial investigators when data were unclear or not reported. We graded the certainty of the evidence using the GRADE approach. We followed standard methods as recommended by Cochrane.

MAIN RESULTS

We included 27 trials with a total of 2099 participants with mixed diagnoses and comparisons of interventions. Seventeen studies reported adequate methods of randomization, and seven reported adequate allocation concealment. Data collection and follow-up times varied.Four trials compared an aqueous shunt (Ahmed or Baerveldt) with trabeculectomy, of which three reported one-year outcomes. At one-year, the difference in IOP between aqueous shunt groups and trabeculectomy groups was uncertain (mean difference (MD) 2.55 mmHg, 95% confidence interval (CI) -0.78 to 5.87; 380 participants; very low-certainty evidence). The difference in logMAR visual acuity was also uncertain (MD 0.12 units, 95% CI -0.07 to 0.31; 380 participants; very low-certainty evidence). In two trials, the difference in visual field score was uncertain (MD -0.25, 95% CI -1.91 to 1.40; 196 participants; very low-certainty evidence). The mean number of antiglaucoma medications was higher in the aqueous shunt group than the trabeculectomy group in one trial (MD 0.80, 95% CI 0.48 to 1.12; 184 participants; low-certainty evidence). The effect on needing additional glaucoma surgery was uncertain between groups in two trials (risk ratio (RR) 0.24, 95% CI 0.04 to 1.36; 329 participants; very low-certainty evidence). In one trial, fewer total adverse events were reported in the aqueous shunt group than the trabeculectomy group (RR 0.59, 95% CI 0.43 to 0.81; 212 participants; very low-certainty evidence). No trial reported quality-of-life outcomes at one-year follow-up.Two trials that compared the Ahmed implant with the Baerveldt implant for glaucoma found higher mean IOP in the Ahmed group at one-year follow-up (MD 2.60 mmHg, 95% CI 1.58 to 3.62; 464 participants; moderate-certainty evidence). The difference in logMAR visual acuity was uncertain between groups (MD -0.07 units, 95% CI -0.27 to 0.13; 501 participants; low-certainty evidence). The MD in number of antiglaucoma medications was within one between groups (MD 0.35, 95% CI 0.11 to 0.59; 464 participants; moderate-certainty evidence). More participants in the Ahmed group required additional glaucoma surgery than the Baerveldt group (RR 2.77, 95% CI 1.02 to 7.54; 514 participants; moderate-certainty evidence). The two trials reported specific adverse events but not overall number of adverse events. Neither trial reported visual field or quality-of-life outcomes at one-year follow-up.One trial compared the Ahmed implant with the Molteno implant for glaucoma over two-year follow-up. Mean IOP was higher in the Ahmed group than the Molteno group (MD 1.64 mmHg, 95% CI 0.85 to 2.43; 57 participants; low-certainty evidence). The differences in logMAR visual acuity (MD 0.08 units, 95% CI -0.24 to 0.40; 57 participants; very low-certainty evidence) and mean deviation in visual field (MD -0.18 dB, 95% CI -3.13 to 2.77; 57 participants; very low-certainty evidence) were uncertain between groups. The mean number of antiglaucoma medications was also uncertain between groups (MD -0.38, 95% CI -1.03 to 0.27; 57 participants; low-certainty evidence). The trial did not report the proportion needing additional glaucoma surgery, total adverse events, or quality-of-life outcomes.Two trials compared the double-plate Molteno implant with the Schocket shunt for glaucoma; one trial reported outcomes only at six-month follow-up, and the other did not specify the follow-up time. At six-months, mean IOP was lower in the Molteno group than the Schocket group (MD -2.50 mmHg, 95% CI -4.60 to -0.40; 115 participants; low-certainty evidence). Neither trial reported the proportion needing additional glaucoma surgery, total adverse events, or visual acuity, visual field, or quality-of-life outcomes.The remaining 18 trials evaluated modifications to aqueous shunts, including 14 trials of Ahmed implants (early aqueous suppression versus standard medication regimen, 2 trials; anti-vascular endothelial growth factor agent versus none, 4 trials; corticosteroids versus none, 2 trials; shunt augmentation versus none, 3 trials; partial tube ligation versus none, 1 trial; pars plana implantation versus conventional implantation, 1 trial; and model M4 versus model S2,1 trial); 1 trial of 500 mm² Baerveldt versus 350 mm² Baerveldt; and 3 trials of Molteno implants (single-plate with oral corticosteroids versus single-plate without oral corticosteroids, 1 trial; double-plate versus single-plate, 1 trial; and pressure-ridge versus double-plate with tube ligation, 1 trial).

AUTHORS' CONCLUSIONS

Information was insufficient to conclude whether there are differences between aqueous shunts and trabeculectomy for glaucoma treatment. While the Baerveldt implant may lower IOP more than the Ahmed implant, the evidence was of moderate-certainty and it is unclear whether the difference in IOP reduction is clinically significant. Overall, methodology and data quality among existing randomized controlled trials of aqueous shunts was heterogeneous across studies, and there are no well-justified or widely accepted generalizations about the superiority of one surgical procedure or device over another.

The efficacy of Alahmady ring implantation in the management of neovascular glaucoma

Purpose

To evaluate the efficacy and safety of Alahmady ring implantation in the management of neovascular glaucoma.

Methods

A total of 15 eyes of 15 patients with intractable neovascular glaucoma with intraocular pressure (IOP) ≥28 mmHg not responding to medical treatment were retrospectively analyzed. All patients had poor visual acuity and underwent Alahmady ring implantation. The ring was designed from fenestrated silicon tube used in lacrimal surgeries and was implanted subsclerally after passing it through the anterior chamber. Patients were followed up for at least 24 months. Success in this study was defined based on IOP ≥8 mmHg and <21 mmHg, with not more than 1 glaucoma drug, and improvement of patient symptoms and signs with maximum use of beta blocker as antiglaucoma drug.

Results

A total of 15 eyes of 15 patients (9 males [60%] and 6 females [40%]) were analyzed in this study. The mean IOP before surgery was 38.6 mmHg (standard deviation [SD]: 6.98) and it was 14.05 mmHg (SD =7.57) after surgery. The follow-up range was 24–36 months. Success of silicon drainage device was defined as an IOP <21 mmHg on the last follow-up visit. Medications included only beta-blockers and topical steroids for those who were without severe complications or for those who were not in a condition to undergo a further glaucoma surgery.

Conclusion

Alahmady ring implantation proves to be a good surgical option for neovascular glaucoma; however, a longer follow-up period is recommended.

Ahmed glaucoma valve implant: surgical technique and complications

Implantation of Ahmed glaucoma valve is an effective surgical technique to reduce intraocular pressure in patients affected with glaucoma. While in the past, the use of this device was reserved to glaucoma refractory to multiple filtration surgical procedures, up-to-date mounting experience has encouraged its use also as a primary surgery for selected cases. Implantation of Ahmed glaucoma valve can be challenging for the surgeon, especially in patients who already underwent previous multiple surgeries. Several tips have to be acquired by the surgeon, and a long learning curve is always needed. Although the valve mechanism embedded in the Ahmed glaucoma valve decreases the risk of postoperative hypotony-related complications, it does not avoid the need of a careful follow-up. Complications related to this type of surgery include early and late postoperative hypotony, excessive capsule fibrosis around the plate, erosion of the tube or plate edge, and very rarely infection. The aim of this review is to describe surgical technique for Ahmed glaucoma valve implantation and to report related complications.

Surgical Outcomes of Ahmed or Baerveldt Tube Shunt Implantation for medically Uncontrolled Traumatic Glaucoma

Aim

To describe postoperative surgical success of either Ahmed or Baerveldt tube shunt implantation for eyes with medically uncontrolled traumatic glaucoma.

Materials and methods

A review was carried out to identify patients with traumatic glaucoma that required tube shunt implantation between 2009 and 2015 at Rutgers University in Newark, New Jersey, USA. Seventeen eyes from 17 patients met inclusion criteria, including at least 3-month postoperative follow-up. The main outcome measure was surgical success at 1-year follow-up after tube implantation.

Results

Mean preoperative intraocular pressure (IOP) was 34.1 ± 8.2 mm Hg on 3.1 ± 1.6 ocular hypotensive medications. Nine eyes (53%) sustained closed globe injury. Ten eyes (59%) received an Ahmed valve shunt and seven eyes (41%) received a Baerveldt tube shunt. Surgical success rate at 1 year postoperatively was 83%. Compared to preoperative, the mean postoperative IOP was significantly lower (16.1 ± 3.5 mm Hg, p < 0.001) on significantly fewer ocular hypertensive medications (1.3 ± 1.6, p = 0.001) at a mean follow-up of 10 months. Mean IOP reduction at last follow-up was 49%. There were three cases of surgical failures: One case of hypotony, one case of tube extrusion with subsequent explan-tation, and one case requiring second tube insertion for IOP control.

Conclusion

Implantation of an Ahmed or Baerveldt tube shunt provided successful control of IOP in patients with medically uncontrollable traumatic glaucoma.

How to cite this article

Yadgarov A, Liu D, Crane ES, Khouri AS. Surgical Outcomes of Ahmed or Baerveldt Tube Shunt Implantation for medically Uncontrolled Traumatic Glaucoma. J Curr Glaucoma Pract 2017;11(1):16-21.

Glaucoma treatment trends: a review

Glaucoma is one of the most common causes of blindness worldwide, and its prevalence is increasing. The aim of the present review is to describe the current medical and surgical treatment trends in the management of open-angle glaucoma. There has been an increase in the availability of glaucoma medications and the use of laser trabeculoplasty over the past decade, with a subsequent decrease in invasive incisional surgery. In addition, a new class of glaucoma procedures, termed microinvasive glaucoma surgery, has emerged, which aims to fill the gap between conservative medical management and more invasive surgery.

Long-term results of non-valved glaucoma drainage implant surgery and glaucoma drainage implant combined with trabeculectomy

Purpose:

The purpose was to investigate the efficacy and complications of nonvalved glaucoma drainage implant (GDI) surgery and GDI combined with trabeculectomy.

Subjects and Methods:

Serial Japanese patients who received GDI were retrospectively investigated. The survival rate of eyes was analyzed using the Kaplan-Meier method, defining death as: (1) Intraocular pressure (IOP) <6 mmHg, or ≥22 mmHg, and <20% reduction of preoperative IOP, (2) additional glaucoma surgery, (3) loss of light perception. Prognostic factors of age, sex, previous surgery, type of glaucoma, synechial closure, preoperative IOP, type of GDI (single-, double-plate Molteno, Baerveldt 350) and GDI combined with trabeculectomy were investigated employing proportional hazards analysis.

Results:

One hundred and twenty-four eyes of 109 patients aged 53.3 ± 7.8 years old were analyzed. Types of GDI were single-plate (15.3%), double-plate Molteno (71.8%), and Baerveldt 350 (12.9%). The results of survival rate analysis were 86.1, 71.1, 71.1, and 64.6% for 1, 3, 5, and 10 years respectively. Thirty-four eyes (27.4%) died because of uncontrolled IOP (19.4%), loss of light perception (5.6%), and additional glaucoma surgery (2.4%). Single-plate Molteno was the only risk factor for failure. Persistent unphysiological hypotony (0.8%) and bullous keratopathy (5.6%) were observed.

Conclusion:

Nonvalved GDI surgery and GDI combined with trabeculectomy using nonabsorbable tube ligature proved to be an excellent device for any type of glaucoma in Japanese patients. Hypotony and corneal endothelial loss are the most serious complication in the long-term results of our patients.

Glaucoma After Open-globe Injury at a Tertiary Care University Hospital: Cumulative Causes and Management

PURPOSE

To investigate causes and treatment modalities of traumatic glaucoma after open-globe injury (OGI).

MATERIALS AND METHODS

The medical records of all patients with postrepair follow-up of OGI at a tertiary care university hospital from January 1996 to December 2010 were reviewed. These patients had persistent elevated intraocular pressure (IOP) of >21 mm Hg at 2 consecutive visits, with or without optic disc damages.

RESULTS

Over the 14-year study period, 41 eyes of 41 patients with repaired OGI that developed glaucoma were identified. In the early stage (within 1 mo), high IOP levels occurred owing to the presence of unremoved lens particles in 11 patients (26.8%), inflammation in 6 patients (14.6%), and hyphema in 3 patients (7.3%). In the intermediate stage (2 to 6 mo), the IOP increased owing to the presence of synechial angle closure in 9 patients (21.9%) and ghost cells in 3 patients (7.3%). In the late stage (>6 mo), the IOP rose owing to the presence of unremoved lens particles in 2 patients (4.8%), angle recession in 4 patients (9.7%), and synechial angle closure in 3 patients (7.3%). Surgical interventions included trabeculectomy in 9 eyes (22%), lens aspiration in 9 eyes (22%), cyclophotocoagulation (CPC) in 5 eyes (12.2%), anterior chamber washout in 3 eyes (7.3%), and tube surgery in 2 eyes (4.9%).

CONCLUSIONS

Traumatic glaucoma is not uncommon long-term complication after OGI. It is important to inspect the association between the initial cause and achieving a successful treatment. Surgical intervention may be crucial in the majority of cases.

Risk factors for tube exposure as a late complication of glaucoma drainage implant surgery

Purpose

The purpose of this study was to evaluate the risk factors for tube exposure after glaucoma drainage implant surgery.

Patients and methods

This was a retrospective case-controlled observational study of 64 eyes from 64 patients. Thirty-two eyes of 32 patients with tube erosion requiring surgical revision were compared with 32 matched control eyes of 32 patients. Univariate and multivariate risk factor analyses were performed.

Results

Mean age was significantly younger in the tube exposure group compared with the control group (48.2±28.1 years versus 67.3±18.0 years, respectively; P=0.003). The proportion of diabetic patients (12.5%) in the tube exposure group was significantly less (P=0.041) compared with the control group (37.5%). Comparisons of the type and position of the drainage implant were not significantly different between the two groups. The average time to tube exposure was 17.2±18.0 months after implantation of the drainage device. In both univariate and multivariate analyses, younger age (P=0.005 and P=0.027) and inflammation prior to tube exposure (P≤0.001 and P=0.004) were significant risk factors. Diabetes was a significant risk factor only in the univariate analysis (P=0.027).

Conclusion

Younger age and inflammation were significant risk factors for tube exposure after drainage implant surgery.

Glaucoma after open globe injury

Ocular trauma remains a core root of avoidable blindness worldwide. Corneal scarring, lens injury, glaucoma, vitreous hemorrhage, retinal or choroidal detachment and endophthalmitis are sequel to ocular trauma that can lead to blindness. Very few studies have been published to tackle the risk of developing post-traumatic glaucoma after open globe injuries (OGI), however, there are many articles discussing closed eye injury. This review article aims to cover the incidence, risk factors, causes and treatment of glaucoma after open globe injury.

Outcomes of glaucoma reoperations in the Tube Versus Trabeculectomy (TVT) Study

PURPOSE

To describe the incidence and outcomes of reoperations for glaucoma in the Tube Versus Trabeculectomy (TVT) Study.

DESIGN

Cohort study of patients in a multicenter randomized clinical trial.

METHODS

The TVT Study enrolled 212 patients with medically uncontrolled glaucoma who had previous cataract and/or glaucoma surgery. Randomization assigned 107 patients to surgery with a tube shunt (350 mm(2) Baerveldt glaucoma implant) and 105 patients to trabeculectomy with mitomycin C (0.4 mg/mL for 4 minutes). Data were analyzed from patients who failed their assigned treatment and had additional glaucoma surgery. Outcome measures included intraocular pressure (IOP), use of glaucoma medications, visual acuity, surgical complications, and failure (IOP >21 mm Hg or not reduced by 20%, IOP ≤5 mm Hg, additional glaucoma surgery, or loss of light perception vision).

RESULTS

Additional glaucoma surgery was performed in 8 patients in the tube group and 18 patients in the trabeculectomy group in the TVT Study, and the 5-year cumulative reoperation rate was 9% in the tube group and 29% in the trabeculectomy group (P = .025). Follow-up (mean ± SD) after additional glaucoma surgery was 28.0 ± 16.0 months in the tube group and 30.5 ± 20.4 months in the trabeculectomy group (P = .76). At 2 years after a glaucoma reoperation, IOP (mean ± SD) was 15.0 ± 5.5 mm Hg in the tube group and 14.4 ± 6.6 mm Hg in the trabeculectomy group (P = .84). The number of glaucoma medications (mean ± SD) after 2 years of follow-up was 1.1 ± 1.3 in the tube group and 1.4 ± 1.4 in the trabeculectomy group (P = .71). The cumulative probability of failure at 1, 2, 3, and 4 years after additional glaucoma surgery was 0%, 43%, 43%, and 43%, respectively, in the tube group, and 0%, 9%, 20%, and 47% in the trabeculectomy group (P = .28). Reoperations to manage complications were required in 1 patient in the tube group and 5 patients in the trabeculectomy group (P = .63).

CONCLUSIONS

The rate of reoperation for glaucoma was higher following trabeculectomy with mitomycin C than tube shunt surgery in the TVT Study. Similar surgical outcomes were observed after additional glaucoma surgery, irrespective of initial randomized treatment in the study.

Glaucoma drainage devices: state of the art

Glaucoma drainage devices (GDDs) create an alternate aqueous pathway by channeling aqueous from the anterior chamber through a long tube to an equatorial plate, inserted under the conjunctiva, which promotes bleb formation. GDDs are being used more frequently in the treatment of glaucoma, both as the primary procedure of choice and following failure of trabeculectomy operations. This article outlines the current concepts involving different GDDs, surgical techniques and a review of the current literature. In addition, the importance of the biomaterial and its implications for the success of the operation are discussed.

Tenon advancement and duplication technique to prevent postoperative Ahmed valve tube exposure in patients with refractory glaucoma

PURPOSE

To present and compare the long-term results of Dr. Tamcelik's previously described technique of Tenon advancement and duplication with the conventional Ahmed glaucoma valve (AGV) implantation technique in patients with refractory glaucoma.

METHODS

This study was a multicenter, retrospective case series that included 303 eyes of 276 patients with refractory glaucoma who underwent glaucoma valve implantation surgery. The patients were divided into three groups according to the surgical technique applied and the outcomes compared. In group 1, 96 eyes of 86 patients underwent AGV implant surgery without patch graft; in group 2, 78 eyes of 72 patients underwent AGV implant surgery with donor scleral patch; in group 3, 129 eyes of 118 patients underwent Ahmed valve implant surgery with "combined short scleral tunnel with Tenon advancement and duplication technique". The endpoint assessed was tube exposure through the conjunctiva.

RESULTS

In group 1, conjunctival tube exposure was seen in 11 eyes (12.9 %) after a mean 9.2 ± 3.7 years of follow-up. In group 2, conjunctival tube exposure was seen in six eyes (2.2 %) after a mean 8.9 ± 3.3 years of follow-up. In group 3, there was no conjunctival exposure after a mean 7.8 ± 2.8 years of follow-up. The difference between the groups was statistically significant. (P = 0.0001, Chi-square test).

CONCLUSION

This novel surgical technique combining a short scleral tunnel with Tenon advancement and duplication was found to be effective and safe to prevent conjunctival tube exposure after AGV implantation surgery in patients with refractory glaucoma.

Treatment outcomes in the Tube Versus Trabeculectomy (TVT) study after five years of follow-up

PURPOSE

To report 5-year treatment outcomes in the Tube Versus Trabeculectomy (TVT) Study.

DESIGN

Multicenter randomized clinical trial.

METHODS

SETTINGS

Seventeen clinical centers.

STUDY POPULATION

Patients 18 to 85 years of age who had previous trabeculectomy and/or cataract extraction with intraocular lens implantation and uncontrolled glaucoma with intraocular pressure (IOP) ≥18 mm Hg and ≤40 mm Hg on maximum tolerated medical therapy.

INTERVENTIONS

Tube shunt (350-mm(2) Baerveldt glaucoma implant) or trabeculectomy with mitomycin C ([MMC]; 0.4 mg/mL for 4 minutes).

MAIN OUTCOME MEASURES

IOP, visual acuity, use of supplemental medical therapy, and failure (IOP >21 mm Hg or not reduced by 20%, IOP ≤5 mm Hg, reoperation for glaucoma, or loss of light perception vision).

RESULTS

A total of 212 eyes of 212 patients were enrolled, including 107 in the tube group and 105 in the trabeculectomy group. At 5 years, IOP (mean ± SD) was 14.4 ± 6.9 mm Hg in the tube group and 12.6 ± 5.9 mm Hg in the trabeculectomy group (P = .12). The number of glaucoma medications (mean ± SD) was 1.4 ± 1.3 in the tube group and 1.2 ± 1.5 in the trabeculectomy group (P = .23). The cumulative probability of failure during 5 years of follow-up was 29.8% in the tube group and 46.9% in the trabeculectomy group (P = .002; hazard ratio = 2.15; 95% confidence interval = 1.30 to 3.56). The rate of reoperation for glaucoma was 9% in the tube group and 29% in the trabeculectomy group (P = .025).

CONCLUSIONS

Tube shunt surgery had a higher success rate compared to trabeculectomy with MMC during 5 years of follow-up in the TVT Study. Both procedures were associated with similar IOP reduction and use of supplemental medical therapy at 5 years. Additional glaucoma surgery was needed more frequently after trabeculectomy with MMC than tube shunt placement.

The management of complicated glaucoma

Complicated glaucomas present considerable diagnostic and management challenges. Response to treatment can be unpredictable or reduced compared with other glaucomas. However, target intraocular pressure and preservation of vision may be achieved with selected medical, laser and surgical treatment. The evidence for such treatment is expanding and consequently affords clinicians a better understanding of established and novel techniques. Herein we review the mechanisms involved in the development of complicated glaucoma and the current evidence supporting its management.

What is new after 40 years of glaucoma implants

Forty years ago, Molteno introduced the prototype of the present day long tube implant. Since then, modifications in size and shape and introduction of valve system have taken place. Aqueous has been shown to contain proinflammatory substances that have been shown to influence the thickness of the bleb wall, and the hypertensive phase has been seen with the implants. The effect of the aqueous may be modified by the use of systemic antiinflammatory medication or by surgical modification, namely supra-Tenon insertion of the implant. Recent studies have shown that tube implantation is as efficacious as trabeculectomy in patients who were either pseudophakic or earlier had failed filters. Newer nontube implants, such as the Express shunt, have been introduced along with others, such as the gold micro shunt implant and the iStent, presently in clinical trials.

A novel surgical technique to prevent postoperative Ahmed valve tube exposure through conjunctiva: tenon advancement and duplication

BACKGROUND AND OBJECTIVE

To present and evaluate a novel surgical technique to prevent exposure of the Ahmed valve implant tube (New World Medical, Rancho Cucamonga, CA) through conjunctiva in congenital glaucoma called "combined short scleral tunnel technique with Tenon advancement and duplication."

PATIENTS AND METHODS

Patients with failed previous congenital glaucoma surgeries were divided into two groups. In group 1, 32 eyes of 28 patients with a mean age of 8.82 +/- 5.39 years underwent classic Ahmed valve implant surgery. In group 2, 28 eyes of 24 patients with a mean age of 8.79 +/- 5.55 years underwent the novel combined short scleral tunnel with Tenon advancement and duplication technique.

RESULTS

After a mean 31.68 +/- 9.25 months of follow-up, conjunctival tube exposure was seen in 3 patients (9.4%) in group 1. There was no conjunctival tube exposure in group 2 after a mean 34.96 +/- 7.93 months of follow-up.

CONCLUSION

The combined short scleral tunnel with Tenon advancement and duplication technique is able to prevent conjunctival tube exposure after Ahmed valve implantation surgery in patients with congenital glaucoma.

Deep sclerectomy with the Ex-PRESS X-200 implant for the surgical treatment of glaucoma

The efficacy and safety of a newly designed Ex-PRESS X-200 drainage device for the surgical treatment of glaucoma was evaluated. A clinical, prospective, monocentric, non-randomised, unmasked study on patients with medically uncontrolled glaucoma was performed. A superficial scleral flap was created. A posterior deep sclerectomy (DS) was dissected without opening the Schlemm's canal and an Ex-PRESS X-200 device was inserted under the scleral flap into the anterior chamber to drain aqueous humour into the intrascleral space. Biomicroscopy, best-corrected visual acuity (BCVA), applanation intra-ocular pressure (IOP) measurements, and fundus examination were performed before surgery, on the first day, the first week, and 1, 2, 3, 6, 12 and 18 months after surgery. The mean follow-up was 18.6 ± 2.4 months (mean ± SD) for the 26 eyes that were treated with the Ex-PRESS X-200 device. Pre-operatively, the mean BCVA was 0.6 ± 0.3, the mean IOP was 22.0 ± 5.1 mmHg, and the mean number of medications per patients was 2.8 ± 0.8. Eighteen months after surgery the mean BCVA was 0.5 ± 0.4, the mean IOP was reduced to 12.0 ± 3.9 mmHg, and the mean number of medications per patient was 0.6 ± 1.2. Eighty-five percent of patients achieved an IOP < 18 mmHg with or without medication and 69% without medication. Post-operative complications were hyphaema (15%), Seidel (15%), encysted blebs (54%) and bleb fibrosis in 8% of patients. Mitomycin C(MMC) was administered to 15 patients (58%) with needling being performed on 10 (38%) of these patients. Mid-term results of DS with the Ex-PRESS X-200 implant demonstrated its efficacy in controlling IOP with few post-operative complications in difficult eyes with an increased risk of surgery failure.

Ahmed glaucoma valve and single-plate Molteno implants in treatment of refractory glaucoma: a comparative study

PURPOSE

To report 2-year follow-up data after Ahmed valve implantation (New World Medical, Inc) and Molteno single-plate implantation surgical treatment of refractory glaucoma.

DESIGN

Prospective, randomized, comparative study.

METHODS

Patients with refractory glaucoma, defined as uncontrolled intraocular pressure (IOP) of more than 21 mm Hg despite maximal antiglaucoma medication, previously failed nonseton surgical treatment, or a combination thereof were included. Ninety-two patients were allocated randomly to each of the study groups and underwent implantation of either the Ahmed valve implant (model FP7; 184 mm(2) surface area) or Molteno single-plate implant (134 mm(2) surface area) and were followed up for 24 months. Main outcome measures were IOP and surgical success rate. Other outcome measures were changes in visual acuity, number of ant-glaucoma medications, mean deviation of visual field, and rate of intraoperative and postoperative complications.

RESULTS

Those who successfully completed the trial (28 in the Molteno group and 29 in the Ahmed group) achieved significantly less IOP and fewer glaucoma medications, but worse visual acuity 24 months after surgery. The Molteno group, compared with the Ahmed group, achieved significantly lower IOPs after the early postoperative period until the end of the study. Both groups reasonably maintained visual field during the follow-up. The rate of surgical failure was comparable in both groups. Median survival time was 24 months for both groups. There were no devastating intraoperative or postoperative complications in either group.

CONCLUSIONS

Both Ahmed and Molteno implants successfully preserved visual field, although IOP control was more pronounced in the Molteno implant group.

Three-year follow-up of the tube versus trabeculectomy study

PURPOSE

To report 3-year results of the Tube Versus Trabeculectomy (TVT) Study.

DESIGN

Multicenter randomized clinical trial.

METHODS

SETTING

Seventeen clinical centers.

STUDY POPULATION

Patients 18 to 85 years of age who had previous trabeculectomy, cataract extraction with intraocular lens implantation, or both and uncontrolled glaucoma with intraocular pressure (IOP) > or =18 mm Hg and < or =40 mm Hg on maximum tolerated medical therapy.

INTERVENTIONS

A 350-mm(2) Baerveldt glaucoma implant or trabeculectomy with mitomycin C (MMC 0.4 mg/ml for 4 minutes).

MAIN OUTCOME MEASURES

IOP, visual acuity, use of supplemental medical therapy, surgical complications, and failure (IOP >21 mm Hg or not reduced by 20%, IOP < or =5 mm Hg, reoperation for glaucoma, or loss of light perception vision).

RESULTS

A total of 212 eyes of 212 patients were enrolled, including 107 in the tube group and 105 in the trabeculectomy group. At 3 years, IOP (mean +/- standard deviation [SD]) was 13.0 +/- 4.9 mm Hg in the tube group and 13.3 +/- 6.8 mm Hg in the trabeculectomy group (P = .78). The number of glaucoma medications (mean +/- SD) was 1.3 +/- 1.3 in the tube group and 1.0 +/- 1.5 in the trabeculectomy group (P = .30). The cumulative probability of failure during the first 3 years of follow-up was 15.1% in the tube group and 30.7% in the trabeculectomy group (P = .010; hazards ratio, 2.2; 95% confidence interval, 1.2 to 4.1). Postoperative complications developed in 42 patients (39%) in the tube group and 63 patients (60%) in the trabeculectomy group (P = .004). Surgical complications were associated with reoperation and/or loss of > or =2 Snellen lines in 24 patients (22%) in the tube group and 28 patients (27%) in the trabeculectomy group (P = .58).

CONCLUSIONS

Tube shunt surgery had a higher success rate compared to trabeculectomy with MMC during the first 3 years of follow-up in the TVT Study. Both procedures were associated with similar IOP reduction and use of supplemental medical therapy at 3 years. While the incidence of postoperative complications was higher following trabeculectomy with MMC relative to tube shunt surgery, most complications were transient and self-limited.