Outcomes of the Second Aqueous Shunt Implant Versus Transscleral Cyclophotocoagulation Treatment Study: A Randomized Comparative Trial

Outcomes of Ahmed Glaucoma Valve Implantation with Subsequent Trans-Scleral Diode Cyclophotocoagulation as the Main Intervention if IOP Remained Medically Uncontrolled

Purpose

To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) implantation with subsequent trans-scleral diode cyclophotocoagulation (CPC) as the main intervention if IOP remained medically uncontrolled.

Patients and Methods

Charts of 108 consecutive eyes (90 patients) that underwent AGV implantation from 2003 to 2018 at a single clinical practice were retrospectively reviewed. The procedure was considered a failure if any of the following occurred: additional incisional glaucoma surgery, IOP >21 mmHg or < 20% reduction from baseline on 2 consecutive study visits after 3 months, IOP ≤ 5 mmHg on 2 consecutive study visits after 3 months, loss of light perception, or AGV removal.

Results

The mean follow-up time was 5.4 ± 3.1 years. Diode CPC was performed in 32%. The mean IOP was 24.8 ± 8.2 mmHg before intervention, and 12.5 ± 5.6 mmHg at last follow-up (p<0.0001). The mean logMAR VA decreased by 0.24 (p=0.002). The success rate was 68%. The reasons for failure were additional incisional glaucoma surgery in 7%, AGV removal in 4%, loss of light perception in 4%, inadequate IOP reduction in 13%, and IOP ≤ 5 mm HG in 6%. The probability of survival by Kaplan Meier analysis was 88%, 76% and 69% at 1, 3, and 5 years after the procedure, respectively. Complications of AGV and CPC were comparable to those previously reported in the literature.

Conclusion

The treatment approach of AGV implantation with subsequent trans-scleral diode CPC, as needed, was successful in over 2/3rd of subjects. This study adds to the literature supporting the use of CPC when IOP is medically uncontrolled after AGV.

The Secondary Childhood Glaucomas

The secondary childhood glaucomas are a heterogenous group, often associated with other ocular or systemic abnormalities. These childhood glaucomas are distinct from primary childhood glaucomas, both in terms of their clinical features and their response to conventional treatment. Surgical management can be challenging in children with secondary glaucoma. On average, this group undergo more surgical procedures and revisions than those with primary congenital glaucoma. We provide a synopsis of secondary childhood glaucomas in terms of classification, clinical features, and management strategies, with emphasis on recent developments.

Failed Ahmed glaucoma valves: trabeculectomy versus repeat shunt surgery

INTRODUCTION

To investigate the outcomes of trabeculectomy (TRAB) versus repeat Ahmed glaucoma valve (re-AGV) implantation in eyes with Ahmed glaucoma valve (AGV) failure.

METHODS

This quasi-experimental study includes patients with failed AGV implants requiring additional surgical intervention between 2018 and 2022. Patients in the TRAB group underwent a fornix-based procedure with mitomycin C 0.01% injection (0.1 mL). Eyes in the re-AGV group underwent repeat shunt surgery. The choice of the procedure was based on conjunctival condition. The primary outcome measure was surgical success rate based on various intraocular pressure (IOP) targets and percentages of IOP reduction from baseline: IOP ≤ 21 mmHg and 20% reduction (conventional criteria), IOP ≤ 18 and > 20% reduction (criterion A), IOP ≤ 15 and > 25% reduction (criterion B), and IOP ≤ 12 and > 30% reduction (criterion C).

RESULTS

Forty-eight eyes of 48 patients were operated and reported herein, consisting of 22 eyes of 22 patients undergoing TRAB and 26 eyes of 26 subjects undergoing re-AGV. No significant difference was observed between the study groups in terms of initial diagnoses, baseline IOP or the number of prior surgeries. The cumulative probability of survival at one year was significantly higher in the trabeculectomy group using the three stricter success definitions. In both study groups, IOP was significantly reduced from baseline at all postoperative visits, and was significantly lower in the TRAB group at all time points beyond one month. At 12 months, 5% of TRAB versus 48% of re-AGV eyes required glaucoma medications (P < 0.001). The rate of complications was comparable between the study groups (P = 0.76) but there was a trend toward a greater need for repeat surgery in the re-AGV group (4 eyes versus nil, P = 0.07).

CONCLUSIONS

Trabeculectomy can be considered a safe and effective surgical option in eyes with failed AGV leading to significantly lower IOP levels and more favorable success rates than re-AGV in selected patients.

Defining the role of ab externo Xen gel stent in glaucomatous eyes with prior failed surgical intervention

PURPOSE

To evaluate the safety and efficacy of Xen45 Gel stent (Xen; Allergan) in eyes that have failed prior surgical intervention, compared to traditional glaucoma drainage device (GDD) or continuous-wave cyclophotocoagulation (CPC). Since this population has low expected success rates with additional surgery, it is vital to compare to standard-of-care surgical options.

METHODS

Retrospective, single-center, case-control study of ab externo transconjunctival Xen shunt in eyes that have previously undergone trabeculectomy and/or GDD surgery. Postoperative data were collected for 18 months. Failure was defined as no light perception, additional glaucoma surgery required, or intraocular pressure (IOP) of < 6 mmHg after 6 weeks postoperatively.

RESULTS

Eighteen Xen eyes and 36 control eyes matched on both glaucoma type and previous glaucoma surgeries were included. Seventy-two percent had primary open angle glaucoma, 11% uveitic, 6% primary angle closure, 6% pseudoexfoliation, and 6% pigmentary glaucoma. Fifty-six percent of eyes in each group had prior trabeculectomy, 28% of Xen and 31% of control eyes had prior GDD, and 17% of Xen and 14% of control eyes had both. Baseline medicated IOP was lower in the Xen group (21.8 ± 7.2) compared to controls (27.5 ± 9.4, P = 0.043). The cumulative failure rate at year 1 was 17% for Xen and 20% for controls (P = 0.57). Mean survival time was 14.1 (± 1.5) months and 11.4 (± 0.6) months for controls. There was no difference in minor complication rates between groups (P = 0.65), but the Xen group had a significantly lower rate of serious complications (P = 0.043) defined as vision threatening or requiring surgical intervention in the operating room. When censored for additional glaucoma procedures, there were no differences at year 1 in IOP, change in IOP, number of IOP-lowering medications, or number of medications reduced from baseline.

CONCLUSIONS

The Xen shunt provides a reasonable alternative to current standard of care, with a similar failure rate at year 1, with a noninferior IOP reduction compared to GDD and CPC, and a preferred safety profile.

Direct Costs of Second Aqueous Shunt Implant Versus Transscleral Cyclophotocoagulation (The Assists Trial)

PRCIS

The cost of cyclophotocoagulation is less than the cost of a second glaucoma drainage device.

PURPOSE

To compare the total direct costs of implantation of a second glaucoma drainage device (SGDD) with transscleral cyclophotocoagulation (CPC) for patients with inadequately controlled intraocular pressure (IOP) reduction, despite the presence of a preexisting glaucoma drainage device in the ASSISTS clinical trial.

METHODS

We compared the total direct cost per patient, including the initial study procedure, medications, additional procedures, and clinic visits during the study period. The relative costs for each procedure during the 90-day global period and the entire study period were compared. The cost of the procedure, including facility fees and anesthesia costs, were determined using the 2021 Medicare fee schedule. Average wholesale prices for self-administered medications were obtained from AmerisourceBergen.com. The Wilcoxon rank sum test was used to compare costs between procedures.

RESULTS

Forty-two eyes of 42 participants were randomized to SGDD (n=22) or CPC (n=20). One CPC eye was lost to follow-up after initial treatment and was excluded. The mean (±SD, median) duration of follow-up was 17.1 (±12.8, 11.7) months and 20.3 (±11.4, 15.1) months for SGDD and CPC, respectively ( P =0.42, 2 sample t test). The mean total direct costs (±SD, median) per patient during the study period were $8790 (±$3421, $6805 for the SGDD group) and $4090 (±$1424, $3566) for the CPC group ( P <0.001). Similarly, the global period cost was higher in the SGDD group than in the CPC group [$6173 (±$830, $5861) vs. $2569 (±$652, $2628); P <0.001]. The monthly cost after the 90-day global period was $215 (±$314, $100) for SGDD and $103 (±$74, $86) for CPC ( P =0.31). The cost of IOP-lowering medications was not significantly different between groups during the global period ( P =0.19) or after the global period ( P =0.23).

CONCLUSION

The total direct cost in the SGDD group was more than double that in the CPC group, driven largely by the cost of the study procedure. The costs of IOP-lowering medications were not significantly different between groups. When considering treatment options for patients with a failed primary GDD, clinicians should be aware of differences in costs between these treatment strategies.

Surgical Outcomes of Glaucoma Drainage Device Implantation in Refractory Glaucoma Patients in Thailand

Purpose

To study the surgical outcomes of glaucoma drainage device (GDD) implantation in refractory glaucoma patients.

Patients and Methods

Retrospective chart review of glaucoma patients undergoing GDD implantation, Ahmed glaucoma valve (AGV), Baerveldt glaucoma implants (BGI), and Aurolab aqueous drainage implantation (AADI) from January 2012 to June 2021. Glaucoma patients were classified into two groups: primary glaucoma including: primary open angle glaucoma (POAG), primary angle closure glaucoma (PACG) and juvenile open angle glaucoma (JOAG) and secondary glaucoma including: neovascular glaucoma (NVG), ocular surgery (vitreoretinal surgery, scleral buckling procedure, postoperative extra capsular cataract extraction, scleral fixation intraocular lens, penetrating keratoplasty), intraocular trauma, uveitis glaucoma, lens-induced glaucoma, pseudoexfoliation glaucoma (PXG), iridocorneal endothelial (ICE) syndromes and Axenfeld Rieger Syndrome. Surgical outcomes were studied.

Results

Primary glaucoma included 57 eyes from 49 patients. Secondary glaucoma included 87 eyes from 85 patients. The cumulative probability of complete or qualified success of refractory glaucoma patients at five years were 53.4% (95%CI: 38.4%, 66.3%). Higher success rate was discovered in primary glaucoma at 65.8% (95%CI: 38.4%, 83.3%) than 45.2% (95%CI: 26.9%, 61.9%) in secondary glaucoma group significantly with p=0.003. While the results among success rate, adverse events and complications was not different between types of GDD. Predictors for failure were neovascular glaucoma with unadjusted hazard ratio (HR) 3.62 (95%CI: 1.45, 9.04) with p=0.006, and lens-induced glaucoma with adjusted HR 4.19 (95%CI: 1.10, 15.86) with p=0.035 in multivariable analysis. Tube malposition and occlusion were the most frequent adverse events at 11.11%, corneal decompensation at 5.5%, hypotony at 2% in the nonvalved group, and endophthalmitis at 0.69%.

Conclusion

Surgical success in refractory primary glaucoma was superior to secondary glaucoma with no difference between nonvalved and valved GDD implantation. Lens-induced glaucoma was a strong predictor for failure in GDD implantation.