Adjunctive triamcinolone acetonide for Ahmed glaucoma valve implantation: a randomized clinical trial

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.

Aqueous Shunts with Extraocular Reservoir for Open-Angle Adult Glaucoma: A Report by the American Academy of Ophthalmology

PURPOSE

To evaluate the recently published literature on the efficacy and safety of the use of aqueous shunts with extraocular reservoir for the management of adult open-angle glaucomas (OAGs).

METHODS

A search of peer-reviewed literature was last conducted in April 2023 of the PubMed database and included only articles published since the last aqueous shunt Ophthalmic Technology Assessment, which assessed articles published before 2008. The abstracts of these 419 articles were examined, and 58 studies were selected for full-text analysis. After inclusion and exclusion criteria were applied, 28 articles were selected and assigned ratings by the panel methodologist according to the level of evidence. Twenty-five articles were rated level I and 3 articles were rated level II. There were no level III articles.

RESULTS

Implantation of aqueous shunts with extraocular reservoir can lower intraocular pressure (IOP) by between one-third and one-half of baseline IOP, depending on whether it is undertaken as the primary or secondary glaucoma surgery. Success rates for aqueous shunts were found to be better than for trabeculectomies in eyes with prior incisional surgery. Conversely, in eyes without prior incisional surgery, implantation of aqueous shunts was found to have an overall lower success rate as the primary glaucoma procedure compared with trabeculectomy. Although both valved and nonvalved aqueous shunts with extraocular reservoir were effective, the nonvalved device generally achieved slightly lower long-term IOPs with fewer glaucoma medications and less need for additional glaucoma surgery. Both devices slow the rates of visual field progression with efficacy comparable with that of trabeculectomy. Early aqueous humor suppression after aqueous shunt implantation is recommended for the management of the postoperative hypertensive phase and long-term IOP control. No strong evidence supports the routine use of mitomycin C with aqueous shunt implantation for OAG.

CONCLUSIONS

Implantation of aqueous shunts with extraocular reservoir, including valved or nonvalved devices, has been shown to be an effective strategy to lower IOP. Strong level I evidence supports the use of aqueous shunts with extraocular reservoir by clinicians for the management of adult OAG.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Capsulectomy Shunt Revision versus Repeat Shunt Implantation Following Ahmed Glaucoma Valve Failure in Refractory Glaucoma

PURPOSE

To investigate the efficacy of capsulectomy shunt revision (CSR) compared with the implantation of a second Ahmed glaucoma valve (re-AGV) in glaucoma patients with failed shunts.

DESIGN

Quasi-experimental study.

SUBJECTS

Forty-six eyes with failed Ahmed glaucoma valves (AGVs) were included in the study; 25 underwent CSR, whereas 21 underwent re-AGV.

METHODS

Patients were scheduled for CSR or re-AGV based on the appearance and accessibility of the existing AGV versus the feasibility for re-AGV in other quadrants. The CSR involved incision and dissection down to the thick fibrous capsule around the AGV plate, which was excised extensively. For re-AGV, the second shunt was implanted in the supranasal or infranasal quadrants.

MAIN OUTCOME MEASURES

Surgical success, defined as intraocular pressure (IOP) > 5 mmHg, ≤ 21 mmHg, IOP reduction ≥ 20% from baseline, and no reoperation for glaucoma. Secondary outcome measures were IOP, number of glaucoma medications, and complications during a 12-month follow-up period.

RESULTS

Mean IOP was significantly lower than preoperative values at all time points in both study groups (P < 0.001). Intraocular pressure decreased significantly from 28.3 ± 5.04 mmHg at baseline to 16.4 ± 2.4 mmHg at final follow-up in the capsulectomy group (P = 0.002). Corresponding IOP values for re-AGV were 30.99 ± 6.2 and 13.6 ± 3.8 mmHg, respectively (P = 0.001). Intraocular pressure in the CSR group was higher than re-AGV during the study (P = 0.003). The cumulative probability of success at 12 months was significantly higher in the re-AGV group (87.5% vs 53.3%, P = 0.002). There was no significant difference in the number of glaucoma medications and overall complications rate between the study groups. Wound leakage was the only complication more common in the CSR group (P = 0.012).

CONCLUSION

In the eyes with a failed AGV, re-AGV and CSR are both effective. Implantation of a second shunt seems more effective than the surgical revision of an existing device; however, the latter procedure may be a viable option in selected cases.

FINANCIAL DISCLOSURE(S)

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

The effect of the hypertensive phase on the long-term outcomes of Ahmed glaucoma valve (AGV) implantation

BACKGROUND

To investigate the long-term effect of hypertensive phase (HP) on the clinical outcomes of Ahmed glaucoma valve (AGV) implantation.

METHOD

The records of patients with different etiologies of glaucoma who underwent AGV implantation with at least 3 years of follow-up were retrospectively reviewed. HP was defined as the IOP > 21 mm Hg during the first three months after surgery. The main outcome measure was cumulative success defined as 5 < IOP ≤ 21 mmHg and 20% reduction from the baseline with or without IOP lowering medications. Results that do not achieve cumulative success or undergo glaucoma reoperation during the follow-up period are considered failures. The secondary outcome measures were intraocular pressure (IOP) and the number of glaucoma medications.

RESULTS

A total of 120 patients (28 patients of HP, 92 patients without HP) with an average age (± SD) of 48.9 ± 19.6 years and a mean follow-up of 4.5 ± 1.4 years were enrolled. The mean duration of survival was 5.3 ± 0.5 years in HP which was significantly shorter than 6.4 ± 0.2 years in non-HP (log rank = 4.2, P = 0.04). Mean IOP and number of IOP lowering agents were higher in postoperative visits at 1,2, 3, and 4 years in HP patients compared with non-HP (all Ps < 0.01). Higher baseline IOP was significantly associated with higher rates of surgical failure.

CONCLUSION

In the long-term follow-up, the duration of survival was significantly longer in the non-HP group. In the non-HP group, the failure rate was significantly lower than the HP group.

Early Intraocular Pressure Control Via Capsule Revision of a Failed Valved Aqueous Shunt During Concurrent Placement of a Nonvalved Aqueous Shunt

PURPOSE

To describe the novel strategy of performing a concurrent capsule revision of a failed pre-existing valved aqueous shunt with implantation of an additional nonvalved aqueous shunt for early postoperative intraocular pressure (IOP) control.

DESIGN

Case report of a single patient.

RESULTS

An 87-year-old man with severe primary open-angle glaucoma in both eyes presented to our clinic. His pseudophakic left eye had a failed superonasal trabeculectomy and an encapsulated superotemporal Ahmed FP7 (New World Medical) aqueous shunt in the anterior chamber. He had previously undergone micropulse cyclophotocoagulation 3 times and excisional goniotomy. Visual acuity in his left eye was 20/30, and IOP was 24 mmHg on 4 topical IOP-lowering medications. An inferonasal Baerveldt 350 (Advanced Medical Optics) aqueous shunt was placed with concurrent revision of the Ahmed capsule. A large block of capsule tissue was excised from the surface of the plate, and 20 mg of subtenon triamcinolone acetonide (Kenalog, Bristol-Myers Squibb) was injected overlying the plate. His IOP ranged between 6 and 15 mmHg in the immediate postoperative period. There were no hypotony-associated complications at any time point. At postoperative month 18, his IOP was 10 mmHg on zero medications.

CONCLUSIONS

In patients with a failed valved aqueous shunt undergoing an additional nonvalved aqueous shunt, a concurrent capsule revision of the valved aqueous shunt can provide early IOP lowering before the nonvalved tube opens.

A new glaucoma drainage implant with the use of Polytetrafluoroethylene (PTFE). A pilot study

Purpose: To investigate the implantation of Polytetrafluoroethylene (PTFE) as a glaucoma drainage device. Methods: This study has been done in two steps. First, the constructed implants have been used in 4 rabbits and the histopathologic response was evaluated. In the second step, the implants were used in the 6 eyes of 6 patients with end-stage glaucoma with uncontrolled IOP and poor visual acuity. The tube was made of two-layer of PTFE membrane measuring 8 * 6 mm with a thickness of 1.8 mm and a silicone tube. The rabbits and the human eyes underwent surgical implantation of the tube in the anterior chamber. The histopathologic evaluation was done using H&E staining. Visual acuity, intraocular pressure and the number of glaucoma medications were assessed before and after the surgery. Results: In the histopathologic evaluation, subconjunctival polarizing fibers of a synthetic mesh infiltrated by fibrovascular septa was seen. A granulomatous inflammatory reaction composed of histiocytes, lymphocytes, and multinucleated giant cells were seen around and between the synthetic bundles. The average age of patients was 63 ± 5.5 years. The mean IOP reached from 36.6 ± 5.7 mmHg at baseline to 16.2 ± 8.9 mmHg at the final follow-up. Patients were followed for an average of 6.6 ± 4.5 months. One patient found hypotony refractory to medical and surgical treatment, which led to implant removal. One patient had uncontrolled IOP and finally led to phthisis bulbi following slow CPC. The remaining four eyes did well during the follow-up. Conclusion: The use of PTFE as a new polymer in tube shunt construction was reported. Larger studies, modification of the PTFE membranes like changing the porosity amount, and size of PTFE membranes might result in different conclusions.

Pretreatment with frequent topical betamethasone in Ahmed glaucoma valve implantation

OBJECTIVE

To evaluate the efficacy of pretreatment with topical betamethasone in Ahmed glaucoma valve (AGV) implantation.

DESIGN

Randomized clinical trial.

PARTICIPANTS

Sixty-two eyes from 62 patients undergoing AGV.

METHODS

We randomly assigned patients undergoing AGV to 2 arms of the study. The case group received AGV implantation with preoperative betamethasone eye drops, and the control group did not receive preoperative betamethasone. Follow-up examinations were performed on postoperative day 1, at least weekly for 4 weeks, and then every 1 to 3 months. Our main outcome measure was the rate of success, defined as intraocular pressure (IOP) <15 mm Hg and IOP ≤18 mm Hg.

RESULTS

We analyzed 62 eyes divided to case (n = 33) and control (n = 29) groups. The success rate was significantly higher in the intervention group than in the control group at 12 months postoperatively when considering either IOP < 15 or IOP < 18 mm Hg as success (p < 0.001) and also at 6 months when considering IOP < 18 mm Hg as success (p < 0.041). The reduction in the number of antiglaucoma medications used postoperatively was significantly higher in the betamethasone group at follow-up at 1 and 3 months and 1 year.

CONCLUSION

Pretreatment with topical betamethasone in AGV implantations increases the success rate and reduces the need for medications.

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.

Local delivery of corticosteroids in clinical ophthalmology: A review

Locally administered steroids have a long history in ophthalmology for the treatment of inflammatory conditions. Anterior segment conditions tend to be treated with topical steroids whilst posterior segment conditions generally require periocular, intravitreal or systemic administration for penetration. Over recent decades, the clinical applications of periocular steroid delivery have expanded to a wide range of conditions including macular oedema from retino-vascular conditions. Formulations have been developed with the aim to provide practical, targeted, longer-term and more efficacious therapy whilst minimizing side effects. Herein, we provide a comprehensive overview of the types of periocular steroid delivery, their clinical applications in ophthalmology and their side effects.

Etiology and management of the hypertensive phase in glaucoma drainage-device surgery

Insertion of glaucoma drainage devices has become a mainstay in the surgical management of multiple forms of glaucoma, and the indications for this procedure continue to expand. A unique clinical challenge in the postoperative care of these devices is the hypertensive phase, a period of postoperative intraocular pressure elevation in the first three months after surgery. We discuss the influence of a variety of factors on the development of the hypertensive phase after glaucoma drainage implantation, including type of device, device material, and device surface area. Furthermore, several intraoperative and postoperative interventions are investigated as attempts to mitigate this phenomenon. Included among these are the use of antimetabolites, collagen matrix, and a variety of approaches to postoperative inflammation and intraocular pressure control. We provide an overview of our current knowledge of the etiology and management of the hypertensive phase.

Fuchs heterochromic iridocyclitis-associated glaucoma: a retrospective comparison of primary Ahmed glaucoma valve implantation and trabeculectomy with mitomycin C

Background: The aim of this study was to compare the safety and efficacy of primary trabeculectomy with mitomycin C and Ahmed glaucoma valve (AGV) implantation in patients with Fuchs heterochromic iridocyclitis (FHIC)-related glaucoma, a rare complication of an uncommon form of uveitis. Methods : In this retrospective comparative case series, 26 FHIC-associated glaucoma patients received trabeculectomy (n=12) or an AGV (n=14). Primary outcome measures were surgical success, defined as intraocular pressure (IOP) ≤21 mmHg, decreasing ≥20% from baseline, and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity (BCVA), and IOP. Results: The follow-up was 34.0±17.7 months in patients that received trabeculectomy and 33.4±18.6 months in AGV (P= 0.837). The cumulative probability of success rate was 41.7% for trabeculectomy and 85.7% for AGV, with no significant difference in complications (P>0.05). The IOP in patients that received trabeculectomy dropped from 23.4±3.3 mmHg to 21.6±5.2 mmHg at the final visit (P= 0.041). In patients that received AGV, the IOP decreased from 24±7.8 to 17.1±2.6 mmHg (P= 0.003). The number of glaucoma medications at baseline were 3.3±0.5 in those that received trabeculectomy and 3±0.6 in those that received AGV (P=0.233), and decreased to 2.4±1.0 (P=0.008) and 1.7±0.6 (P=0.002), respectively. BCVA was equal in both groups and did not change (P>0.05). Conclusion: Primary AGV had a higher success rate than trabeculectomy, with patients also needing fewer medications for the management of FHIC-associated glaucoma.

Fuchs heterochromic iridocyclitis-associated glaucoma: a retrospective comparison of primary Ahmed glaucoma valve implantation and trabeculectomy with mitomycin C

Background: The aim of this study was to compare the safety and efficacy of primary trabeculectomy with mitomycin C and Ahmed glaucoma valve (AGV) implantation in patients with Fuchs heterochromic iridocyclitis (FHIC)-related glaucoma, a rare complication of an uncommon form of uveitis. Methods : In this retrospective comparative case series, 26 FHIC-associated glaucoma patients received trabeculectomy (n=12) or an AGV (n=14). Primary outcome measures were surgical success, defined as intraocular pressure (IOP) ≤21 mmHg, decreasing ≥20% from baseline, and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity (BCVA), and IOP. Results: The follow-up was 34.0±17.7 months in patients that received trabeculectomy and 33.4±18.6 months in AGV (P= 0.837). The cumulative probability of success rate was 41.7% for trabeculectomy and 85.7% for AGV, with no significant difference in complications (P>0.05). The IOP in patients that received trabeculectomy dropped from 23.4±3.3 mmHg to 21.6±5.2 mmHg at the final visit (P= 0.041). In patients that received AGV, the IOP decreased from 24±7.8 to 17.1±2.6 mmHg (P= 0.003). The number of glaucoma medications at baseline were 3.3±0.5 in those that received trabeculectomy and 3±0.6 in those that received AGV (P=0.233), and decreased to 2.4±1.0 (P=0.008) and 1.7±0.6 (P=0.002), respectively. BCVA was equal in both groups and did not change (P>0.05). Conclusion: Primary AGV had a higher success rate than trabeculectomy, with patients also needing fewer medications for the management of FHIC-associated glaucoma.

Impact of same-session trabectome surgery on Ahmed glaucoma valve outcomes

PURPOSE

To evaluate the efficacy and survival rates of same session ab interno trabeculectomy with the trabectome and Ahmed glaucoma valve implant (AT) in comparison to the Ahmed glaucoma valve alone (A).

METHOD

A total of 107 eyes undergoing primary glaucoma surgery were enrolled in this retrospective comparative case series, including 48 eyes which underwent AT and 59 eyes which received A alone. Participants were identified using the procedural terminology codes, and their medical records were reviewed. The primary outcome measure was success defined as IOP > 5 mmHg, ≤ 21 mmHg and ≥ 20% reduction of IOP from baseline at two consecutive visits after 3 months, and no need for glaucoma reoperation. Secondary outcome measures were IOP, the number of glaucoma medications, incidence of a hypertensive phase, and best corrected visual acuity (BCVA).

RESULTS

The cumulative probability of success at 1 year was 70% in AT, and 65% in A (p = 0.85). IOP decreased significantly from 26.6 ± 10.1 mmHg at baseline to 14.7 ± 3.3 mmHg at the final follow-up in AT (p = 0.001). The corresponding numbers for A were 27.8 ± 10.2 and 16.7 ± 4.9, respectively (p = 0.001). The final IOP was significantly lower in AT (p = 0.022). The number of medications at baseline was comparable in both groups (2.6 ± 1.2 in AT and 2.5 ± 1.3 in A, p = 0.851). Corresponding number at 1 year visit was 1.2 ± 2 in AT and 2.8 ± 1.8 in A (p = 0.001). The incidence of a hypertensive phase was 18.7% in AT and 35.5% in A (p = 0.05). HP resolved in only 30% of eyes. The criteria for HP resolution were fulfilled in 9 eyes (30%). There was no difference in the rate of resolution of the hypertensive phase between AT and A (33.3 and 28.5%, respectively, p = 0.67).

CONCLUSION

Ahmed glaucoma valve implant with same session trabectome surgery significantly decreased the rate of the hypertensive phase and postoperative IOP as well as the number of glaucoma medications.