Outcomes of sequential tube shunts in complicated glaucoma

Sequential Ahmed valve implantation after primary implant surgery in two dogs

OBJECTIVE

To report the outcomes of sequential Ahmed valve implantation in two dogs with uncontrolled intraocular pressure (IOP) after primary Ahmed valve implantation.

ANIMALS STUDIED

A 6-year-old castrated male American Cocker Spaniel (case 1) and a 12-year-old spayed female mixed-breed dog (case 2) presented with glaucoma management in the left eyes of both dogs.

PROCEDURES

Primary Ahmed valve implantation was performed because of uncontrolled IOP despite antiglaucoma medications used in both dogs. The IOP was maintained within the normal range for 14 and 2 months after surgery in cases 1 and 2, respectively. In both cases, the IOP gradually increased, which was assumed to be caused by bleb fibrosis. In particular, in case 2, one bleb revision surgery was performed during that period, but it was unsuccessful. Therefore, we decided to perform sequential implantation surgery.

RESULTS

In case 1, hyphema occurred the day after sequential surgery and resolved with anti-inflammatory treatment. In case 2, it occurred immediately after the surgery and resolved after surgical blood clot removal. IOP remained below 15 mmHg, and menace response was positive until 40 and 23 months after the sequential surgery in cases 1 and 2, respectively. As a long-term complication, cataracts occurred at 17 months in case 1 and 10 months in case 2.

CONCLUSIONS AND CLINICAL RELEVANCE

Sequential implantation surgery in the same eye could be an effective alternative for long-term IOP management and vision maintenance. A better understanding of complications and appropriate postoperative management is essential for better outcomes.

Recent Advancements in Glaucoma Surgery-A Review

Surgery has long been an important treatment for limiting optic nerve damage and minimising visual loss in patients with glaucoma. Numerous improvements, modifications, and innovations in glaucoma surgery over recent decades have improved surgical safety, and have led to earlier and more frequent surgical intervention in glaucoma patients at risk of vision loss. This review summarises the latest advancements in trabeculectomy surgery, glaucoma drainage device (GDD) implantation, and minimally invasive glaucoma surgery (MIGS). A comprehensive search of MEDLINE, EMBASE, and CENTRAL databases, alongside subsequent hand searches-limited to the past 10 years for trabeculectomy and GDDs, and the past 5 years for MIGS-yielded 2283 results, 58 of which were included in the final review (8 trabeculectomy, 27 GDD, and 23 MIGS). Advancements in trabeculectomy are described in terms of adjunctive incisions, Tenon's layer management, and novel suturing techniques. Advancements in GDD implantation pertain to modifications of surgical techniques and devices, novel methods to deal with postoperative complications and surgical failure, and the invention of new GDDs. Finally, the popularity of MIGS has recently promoted modifications to current surgical techniques and the development of novel MIGS devices.

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.

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.

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

PRCIS

Short-term overall success rates were high with either SGDD or CPC. However, SGDD was associated with more clinic visits and an increased risk of additional glaucoma surgery. Both treatments were reasonable options for eyes with inadequately controlled IOP after a single GDD.

PURPOSE

The purpose of this study is to compare the implantation of a second glaucoma drainage device (SGDD) and transscleral cyclophotocoagulation (CPC) in eyes with inadequately controlled intraocular pressure (IOP), despite the presence of a preexisting glaucoma drainage device.

METHODS

Patients with inadequately controlled IOP, despite the medical therapy and a preexisting glaucoma drainage device, were enrolled at 14 clinical centers and randomly assigned to treatment with a SGDD or CPC.

MAIN OUTCOME MEASURES

Surgical failure was defined as: (1) IOP ≤5 mm Hg or >18 mm Hg or <20% reduction below baseline on maximum tolerated topical ocular hypotensive therapy, (2) reoperation for glaucoma, or (3) loss of light perception. The primary outcome measure was overall success with or without adjunctive medical therapy.

RESULTS

Forty-two eyes of 42 participants were randomized to SGDD (n=22) or CPC (n=20). Mean duration of follow-up was 18.6 (±12.1; range: 1.1-38.6) months. The cumulative success rate was 79% for SGDD and 88% for CPC at 1 year ( P =0.63). Although the study was underpowered, no significant differences in IOP, postoperative number of IOP-lowering medications, or adverse events were observed. The number of additional glaucoma surgeries ( P =0.003), office visits during the first 3 months ( P <0.001), and office visits per month after month 3 ( P <0.001) were greater in the SGDD group.

CONCLUSIONS

Short-term overall success rates were high with either SGDD or CPC. However, SGDD was associated with more clinic visits and an increased risk of additional glaucoma surgery.

A Meta-analysis on the Outcome of Sequential Glaucoma Drainage Implantation

PRECIS

A meta-analysis shows that second glaucoma drainage implantation can be effective after a failed drainage implant. There is a need for continued glaucoma medications and the risk of corneal decompensation.

PURPOSE

Studies on second glaucoma drainage implantation are small and exploratory. We performed a meta-analysis on the efficacy of second glaucoma drainage implantation.

MATERIALS AND METHODS

The intraocular pressure (IOP) and the number of glaucoma medications were compared preoperative to postoperative after second drainage implantation. Kaplan-Meier survival curves were aggregated and compared with the survival curve from the Tube versus Trabeculectomy study.

RESULTS

Nine studies, all retrospective, were included in the meta-analysis. Our results showed that second drainage implantation significantly lowered the IOP and reduced the number of medications. Most patients still required medications for adequate IOP control. Second drainage implants tended to fail earlier than first drainage implants in the Tube versus Trabeculectomy study. The most common complication after second drainage implants was corneal decompensation.

CONCLUSIONS

Second glaucoma drainage implantation can be considered a viable approach after a failed drainage implant, but patients should be counseled on the need for continued medical therapy and the risk of corneal decompensation.

Safety and Efficacy of Second Ahmed Valve Implant in Refractory Glaucoma

BACKGROUND

Refractory glaucoma still represents a challenge for ophthalmologists to manage intraocular pressure. The present study aimed to evaluate long term efficacy and safety of a second Ahmed valve implantation after the failure of a first implant in patients with refractory glaucoma and elevated intraocular pressure (IOP).

METHODS

Retrospective, multicenter non-comparative case series. Twenty-eight patients were retrospectively recruited between January 2011 and December 2017. Demographic data, glaucoma type, visual acuity, intraocular pressure, medical therapy, and complications were registered. Three criteria of success were established: Type 1 surgical success: IOP ≤ 15 mmHg and a reduction of IOP ≥ 40% from baseline; Type 2 surgical success: IOP ≤ 18 mmHg and a reduction of IOP ≥ 30% from baseline; and Type 3 surgical success: IOP ≤ 21 mmHg and a reduction of IOP ≥ 20% from baseline. Surgical failure has been established as IOP less than 5 mmHg or over 21 mmHg and less than a 20% reduction of IOP from baseline despite medications in two consecutive visits, light perception loss referable to glaucoma, and the necessity for further glaucoma surgery. Failure was observed in six (21%) patients. (3) Results: Mean IOP and mean glaucoma medication number significantly reduced from baseline after the second implantation, and the surgical success rate at 72 months ranged from 10% to 78% based on the different criteria of success. Failure was observed in six (21%) patients.

CONCLUSIONS

This study confirmed the safety and efficacy of a second Ahmed valve implantation in patients with refractory glaucoma and elevated IOP at baseline.

Surgical Outcomes of a Second Ahmed Glaucoma Valve Implantation in Asian Eyes with Refractory Glaucoma

Results

The cumulative failure rates were 9.5%, 20.0%, 32.5%, and 46.0% at six months, one year, two years, and three years of follow-up. At final follow-up, complete success and qualified success rates were 23.8% and 33.3%, respectively; mean IOP and number of medications decreased by 5.6 mmHg (23.9%) and 1.7 mmHg (54.8%), respectively, from preoperative baseline (P < 0.01). More common postoperative complications included hypertensive phase (38.1%), corneal decompensation (23.8%), and tube exposure (14.3%).

Conclusion

An additional AGV implant had good short and modest long-term effectiveness in reducing IOP following a failed glaucoma tube shunt in Asian eyes, with the mentioned common postoperative complications to be actively monitored and managed.

Trabeculectomy Outcomes After Glaucoma Drainage Device Surgery

PURPOSE

To evaluate outcomes of trabeculectomy with adjunctive mitomycin C in patients with uncontrolled intraocular pressure (IOP) after glaucoma drainage device implantation.

MATERIALS AND METHODS

Consecutive patients who had undergone a trabeculectomy after GDD were reviewed. The primary outcome was surgical success with stratified IOP targets based on the following criteria: (A) IOP<18 mm Hg and IOP reduction of 20%; (B) IOP<15 mm Hg and IOP reduction of 25%; (C) IOP<12 mm Hg and IOP reduction of 30%. Secondary outcomes were number of glaucoma medications, complications, and need for additional glaucoma surgery.

RESULTS

Twenty eyes (19 patients) were included for analysis. Median follow-up and age were 3.7 years (range, 1.1 to 10.2 y) and 64.2 years (range, 25.2 to 85.6 y), respectively. Mean IOP (±SD) has dropped from 19.3±4.2 mm Hg preoperatively to 9.8±2.2 mm Hg at 1 year, 8.8±3.2 mm Hg at 3 years and 8.4±1.5 mm Hg at 5 years (P<0.001 for all). Hypotony maculopathy was the only serious complication (2/19 patients; 10%) that needed surgical revision. The cumulative success rate (±SD) for criterion A and B were 73.2% (±10.0%) and 68.2% (±9.5%), respectively, between the first and fifth year of follow-up, for criterion C it was 49.1% (±10.8%) at the first year and 32.7% (±12%) between the second and fifth year of follow-up.

CONCLUSIONS

Trabeculectomy is a viable surgical option to treat IOP that is uncontrolled after GDD implantation.

Factors Associated with Outcomes of Combined Phacoemulsification and Ahmed Glaucoma Valve Implantation

Purpose

To evaluate outcomes and factors associated with surgical failure in patients who underwent combined phacoemulsification and Ahmed glaucoma valve (AGV) implantation.

Methods

This retrospective and longitudinal study enrolled 40 eyes (38 patients) that underwent combined phacoemulsification and AGV implantation. Visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were evaluated preoperatively and postoperatively. Complete success was defined as a last follow-up IOP of 6 to 21 mmHg without medication, qualified success as an IOP of 6 to 21 mmHg with medication, and failure as an IOP of >21 or <6 mmHg.

Results

The mean follow-up period was 18 ± 10 months. Preoperative diagnoses were chronic angle closure glaucoma (35.0%), neovascular glaucoma (22.5%), uveitic glaucoma (17.5%), primary open-angle glaucoma (15.0%), and other (10.0%). IOP decreased from a mean of 30.5 ± 8.7 to 14.5 ± 3.7 mmHg at the last follow-up visit (p < 0.001). Treatment was classified as qualified success in 18 eyes (45%), complete success in 15 (37.5%), and failure in seven (17.5%). Twenty-two eyes (55%) showed improvement in visual acuity. The most common postoperative complication was a transient hypertensive phase (five eyes, 12.5%). Tube-iris touch was associated with surgical failure (hazard ratio, 8.615; p = 0.008).

Conclusions

Combined phacoemulsification and AGV implantation is an effective and safe surgical option for patients with refractory glaucoma and cataract. Postoperative tube-iris touch is an indicator of poor prognosis.

Long-term Outcome of Second Ahmed Valves in Adult Glaucoma

PURPOSE

To evaluate the long-term outcomes of second Ahmed glaucoma valve (AGV) implants in eyes with glaucoma.

DESIGN

Retrospective interventional case series.

METHODS

Patients with sequential second Ahmed valves implanted in the same eye from 1994 to 2016 were included. Success was defined with 3 criteria: (1) intraocular pressure (IOP) ≤ 21 mm Hg and IOP reduction of 20%; (2) IOP ≤ 18 mm Hg and IOP reduction of 25%; and (3) IOP ≤15 mm Hg and IOP reduction of 30%. The primary analysis was the 5-year Kaplan-Meier survival rate for each criterion. Failure was established when the success criterion was not met at 2 consecutive visits at least 3 months after the surgery. Loss of light perception, requirement for additional glaucoma surgery, hypotony maculopathy, and serious complications were also considered failures.

RESULTS

One hundred ten eyes from 104 patients were included with a mean follow-up of 5.0 years (interquartile range [IQR] 1.6-7.33 years). The median (IQR) age at the second AGV was 68.0 (53.5-77.9) years. The median (IQR) time between surgeries was 2.1 (0.7-4.0) years. The 5-year Kaplan-Meier survival rates were 57%, 51%, and 30% for criteria 1, 2, and 3, respectively.

CONCLUSION

A second AGV is effective in reducing IOP in patients who require additional IOP lowering after a first AGV. The success rates are comparable to primary AGV implantation, and to trabeculectomy in eyes with a previously implanted glaucoma drainage device. A second AGV is a viable option in eyes with inadequate IOP levels after a primary AGV.

Combined Phacoemulsification and Ahmed Valve Glaucoma Drainage Implant: A Retrospective Case Series

Purpose

To report on the efficacy and safety of combined phacoemulsification and an Ahmed valve glaucoma drainage implant with respect to visual acuity improvement, intraocular pressure (IOP) control, and requirement for antiglaucoma medication.

Methods

A retrospective chart review was conducted of 41 eyes (31 patients) with coexisting visually significant cataracts and uncontrolled glaucoma who had combined phacoemulsification and Ahmed valve implantation. The outcome measures were: visual acuity, IOP, antiglaucoma medication requirements, and intra- and post-operative complications. Success was categorized as absolute (IOPp<21 mmHg without the need for antiglaucoma medication) and relative (IOPp<21 mmHg with one or more antiglaucoma medications). Failure was considered to be an IOPp<6 mmHg or IOP>21 mmHg on maximally tolerated medications or any devastating complication.

Results

The mean patient age was 67.3±5.9 years old. The mean visual acuity improved from 0.73±0.5 to 0.16±0.16 (p=0.000). The mean IOP decreased from 28.2±3.1 to 16.8±2.1 (p=0.000, 40.4%), while the number of antiglaucoma medication decreased from 2.6±0.66 to 1.2±1.4 (p=0.000). The absolute and relative success rates were 56.1% and 31.7%, respectively; 5 eyes (12.2%) were considered failures. There were no intraoperative complications; postoperative complications occurred in 8 eyes (19.5%). A hypertensive phase was detected in 12 (29.3%) eyes.

Conclusions

Combined phacoemulsification and Ahmed valve glaucoma drainage implantation is a safe and effective alternative to phacotrabeculectomy in patients with coexisting cataract and refractory glaucoma.

Comparison of Efficacy and Complications of Cyclophotocoagulation and Second Glaucoma Drainage Device After Initial Glaucoma Drainage Device Failure

PURPOSE

Compare intraocular pressure (IOP) control and complication rates of a second glaucoma drainage device (GDD) to diode transscleral cyclophotocoagulation (TSCPC) following failure of an initial GDD.

PATIENTS AND METHODS

Eyes with 1 GDD that required a second GDD or TSCPC for glaucoma control were included. Exclusion criteria were a cyclodestructive procedure before initial GDD, no light perception vision, or follow-up <1 year. Failure was defined as ≥1 of (1) reoperation for lowering IOP; (2) explantation of second GDD; (3) persistent hypotony; (4) use of oral carbonic anhydrase inhibitor for lowering IOP in the study eye; or (5) loss of light perception. Reoperation for lowering IOP included additional GDD implantation or additional cyclodestruction, except if additional cyclodestruction was within 6 months of the initial session.

RESULTS

A total of 75 eyes (35 in second GDD; 40 in TSCPC) were included (mean follow-up, 25.5 mo). Both procedures lowered IOP [-11.4 mm Hg (±13.6) for second GDD and -7.8 mm Hg (±11.8) for TSCPC groups] and decreased the number of IOP-lowering medications at the last visit. The second GDD group had significantly greater mean survival time [45.0 mo (±4.2)] than the TSCPC group [26.5 mo (±2.8)] but significantly more postoperative complications (60% of eyes) and non-IOP-related procedures (40% of eyes) than the TSCPC group (20% for postoperative complications and 18% for non-IOP-related procedures).

CONCLUSIONS

Although both second procedures are efficacious in lowering IOP and number of IOP-lowering medications, TSCPC failed earlier, whereas a second GDD had significantly more complications.

Outcomes of Ahmed Glaucoma Valve Revision in Pediatric Glaucoma

PURPOSE

Encapsulation of the Ahmed glaucoma valve (AGV) plate is a common cause for postoperative elevation of intraocular pressure, especially in children. Many reports have described the outcomes of AGV revision in adults. However, the outcomes of AGV revision in children are poorly documented. The aim of this study was to determine the outcomes of AGV revision in children.

DESIGN

Retrospective cross-sectional study.

METHODS

A retrospective chart review of patients less than 15 years of age who underwent AGV revision with a minimum postoperative follow-up of 6 months was conducted. Outcome measures included reduction in intraocular pressure from baseline, survival analysis, and reduction in the number of antiglaucoma medications. Postoperative complications were also noted. Complete success was defined as an IOP of 21 mm Hg or less without medications, while qualified success was defined as having an IOP of 21 mm Hg or less with medications.

RESULTS

A total of 44 eyes met the inclusion criteria. Primary congenital glaucoma was present in 39 eyes (88.6%), aphakic glaucoma in 4 eyes (9.1%), and Peters anomaly-associated glaucoma in 1 eye (2.3%). The mean number of previous surgeries was 1.4, and the mean age was 6.7 years (range, 1.9-13 years) with a median follow-up of 12 months (range, 6-24 months). The IOP was reduced from a preoperative mean of 30.4 (± 10.3) to 24.9 (± 10.6) mm Hg at 6 months postoperatively. Kaplan-Meier analysis showed that the complete success rate at 1 month was 100% followed by a rapid decline at 6 months to 38.6%, 27.7% at 1 year, and 5.5% at 2 years. Qualified success rate was 100% at 1 month followed by a 6-month and 1-year survival rate of approximately 50% and a 2-year survival rate of approximately 16%. The median survival time was 14 months. No specific risk factors for failure were identified. Visual acuity remained unchanged following revision. The most common complication was recurrence of encapsulation with elevated IOP (15.9%). Other complications included hyphema (n = 3; 6.8%), endophthalmitis (n = 1; 2.3%), wound leak (n = 1; 2.3%), and choroidal detachment (n = 2; 4.5%).

CONCLUSION

Although the short-term success rate of AGV revision in children is high, with longer follow-up the success rate decreases significantly.

A Comparison of Sequential Glaucoma Drainage Device Implantation Versus Cyclophotocoagulation Following Failure of a Primary Drainage Device

PURPOSE

To compare sequential glaucoma drainage device (GDD) implantation with transscleral diode cyclophotocoagulation (CPC) following failure of a primary GDD.

MATERIALS AND METHODS

A retrospective review of all patients who underwent GDD implantation at a single institution over 10 years. Patients who required an additional GDD and/or CPC were analyzed. Success was defined as absence of loss of light perception, reoperation for glaucoma, and intraocular pressure (IOP) >21 or <6 at 2 consecutive visits after an initial 3-month period.

RESULTS

Thirty-two patients received sequential GDD. Twenty-one underwent CPC. Cohorts were statistically similar in regards to age, sex, race, and number of previous surgeries. Preoperatively, the GDD cohort had a lower IOP and better visual acuity. The mean length of follow-up was 37.9 months for the GDD group and 46.3 months for CPC. Both procedures significantly reduced IOP; however, CPC led to a greater reduction (P=0.0172). Survival analysis found the 5-year probability of surgical success to be 65.3% for sequential GDD and 58.0% for CPC (P=0.8678). No cases of phthisis occurred in either group. There were 2 cases of endophthalmitis (6.3%) in the GDD group, and none in the CPC group. In eyes without preexisting corneal edema, estimated corneal decompensation probability at 3 years was 31.6% for GDD and 6.7% for CPC (P=0.0828).

CONCLUSIONS

Sequential GDD and CPC are both effective at reducing IOP following the failure of a primary GDD. CPC after GDD failure warrants further investigation as it led to a greater reduction in IOP with fewer serious adverse events.

Evaluation of success after second Ahmed glaucoma valve implantation

Purpose:

To evaluate the outcome of the second Ahmed glaucoma valve (AGV) surgery in eyes with failed previous AGV surgery.

Design:

Retrospective case series.

Patients and Methods:

Following chart review, 36 eyes of 34 patients with second AGV implantation were enrolled in this study. The primary outcome measure was surgical success defined in terms of intraocular pressure (IOP) control using two criteria: Success was defined as IOP ≤21 mmHg (criterion 1) and IOP ≤16 mmHg (criterion 2), with at least 20% reduction in IOP, either with no medication (complete success) or with no more than two medications (qualified success). Kaplan–Meier survival analysis was used to determine the probability of surgical success.

Results:

The average age of the patients was 32.7 years (range 4–65), and the mean duration of follow-up was 21.4 months (range 6–96). Preoperatively, the mean IOP was 26.94 mmHg (standard deviation [SD] 7.03), and the patients were using 2.8 glaucoma medications on average (SD 0.9). The mean IOP decreased significantly to 13.28 mmHg (SD 3.59) at the last postoperative visit (P = 0.00) while the patients needed even fewer glaucoma medications on average (1.4 ± 1.1, P = 0.00). Surgical success of second glaucoma drainage devices (Kaplan–Meier analysis), according to criterion 1, at 6, 12, 18, and 42 months was 94%, 85%, 80%, and 53% respectively, and according to criterion 2, was 94%, 85%, 75%, and 45%, respectively.

Conclusion:

Repeated AGV implantation seems to be a safe modality of treatment with acceptable success rate in cases with failed previous AGV surgery.

Intermediate-term and long-term outcome of piggyback drainage: connecting glaucoma drainage device to a device in-situ for improved intraocular pressure control

IMPORTANCE

This study provides results of a treatment option for patients with failed primary glaucoma drainage device.

BACKGROUND

The study aimed to describe and evaluate the long-term intraocular pressure control and complications of a new technique joining a second glaucoma drainage device directly to an existing glaucoma drainage device termed 'piggyback drainage'.

DESIGN

This is a retrospective, interventional cohort study.

PARTICIPANTS

Eighteen eyes of 17 patients who underwent piggyback drainage between 2004 and 2013 inclusive have been studied. All patients had prior glaucoma drainage device with uncontrolled intraocular pressure.

METHODS

The piggyback technique involved suturing a Baerveldt (250 or 350 mm) or Molteno3 glaucoma drainage device to an unused scleral quadrant and connecting the silicone tube to the primary plate bleb.

MAIN OUTCOME MEASURES

Failure of intraocular pressure control defined as an intraocular pressure greater than 21 mmHg on maximal therapy on two separate occasions or further intervention to control intraocular pressure.

RESULTS

The intraocular pressure was controlled in seven eyes (39%) at last follow-up with a mean follow-up time of 74.2 months. The mean preoperative intraocular pressure was 27.1 mmHg (95% confidence interval 23.8-30.3) compared with 18.4 mmHg (95% confidence interval 13.9-22.8) at last follow-up. The mean time to failure was 57.1 months (95% confidence interval 32.2-82), and the mean time to further surgery was 72.3 months (95% confidence interval 49.9-94.7). Lower preoperative intraocular pressure was associated with longer duration of intraocular pressure control (P = 0.048). If the intraocular pressure was controlled over 2 years, it continued to be controlled over the long term. Two eyes (11%) experienced corneal decompensation.

CONCLUSIONS

Piggyback drainage represents a viable surgical alternative for the treatment of patients with severe glaucoma with failing primary glaucoma drainage device, particularly in those at high risk of corneal decompensation.

Outcomes of Sequential Glaucoma Drainage Implants in Refractory Glaucoma

PURPOSE

To describe the outcomes of eyes that have undergone a second glaucoma drainage implant (GDI) surgery.

METHODS

A retrospective review of eyes that underwent a second GDI surgery from 2006 to 2013 was conducted. Primary outcome measures included intraocular pressure (IOP) reduction and success rates. Secondary outcome measures included glaucoma medication use, visual acuity, and number of reoperations. Success was defined as 6 ≤ IOP ≤ 21 with at least 20% IOP reduction, and no increase in the number of glaucoma medications from baseline at 3 months of follow-up or more.

RESULTS

Sixty-five eyes (63 patients) had a mean follow-up of 22.4 ± 19.9 months. The most frequently placed second GDIs were an Ahmed FP7 (49%) or a Baerveldt 250 (26%) in the inferotemporal (46%) or inferonasal (35%) quadrant. At 3-year follow-up, IOP was reduced from 25.8 ± 7.7 to 17.4 ± 9.9 mm Hg (P = 0.004) and the number of glaucoma medications decreased from 3.6 ± 1.2 to 2.5 ± 1.4 (P = 0.01) compared with baseline. The median time to failure was 24.7 ± 5.8 months. There was no significant difference in failure rates for type of sequential GDI (P = 0.80) or plate location (P = 0.34). There was no significant difference in visual acuity between baseline and 3-year follow-up (P = 1.0). The most common postoperative complication was corneal edema (n = 9, 14%).

CONCLUSIONS

Most eyes undergoing a second GDI achieve adequate IOP control with fewer antiglaucoma medications. Failure rates were similar regardless of quadrant selection or GDI type.

Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush

Objective: To assess the utility of viscoelastic injection to induce bleb expansion and decrease intraocular pressure (IOP) in eyes with encapsulated glaucoma tube shunt blebs.

Design: Case series.

Subjects and participants: Forty-three glaucomatous eyes, including 13 eyes with congenital, 13 uveitic, 5 neovascular, 5 open angle, 4 narrow angle and 3 traumatic glaucomas.

Methods, interventions or testing: All patients underwent viscoelastic flush procedure. A pre-bent 27 or 30-gauge cannula was passed through a 25-gauge paracentesis, advanced over the iris across the anterior chamber, and insinuated into the tube shunt lumen. Once the cannula was firmly lodged in position, 0.45 to 0.85 ml of viscoelastic was injected to hyperinflate the bleb.

Main outcome measures: Paired t-tests were performed comparing preoperative IOP and number of medications used preoperatively vs levels measured at 1, 6, 12, 18 and 24 months.

Results: Intraocular pressure was reduced from a mean preoperative level of 26.0 ± 1.2 (sem) mm Hg to 15.8 ± 1.0 at 1 month, remaining stable thereafter at each 6-month interval with 15.1 ± 1.1 mm Hg at 24 months (p < 0.0001). Medication use did not vary significantly from baseline. Pressure remained < 21 mm Hg after 2 years in 85% of eyes cannulated within 1 year of primary tube shunt implantation (n = 23), and in 62% of eyes cannulated more than 1 year after tube shunt placement (n = 20).

Conclusion: Tube shunt expansion with bolus viscoelastic flush successfully restored encapsulated bleb function, providing a substantial (~10 mm Hg) IOP decrease into the mid-normal pressure range. This persisted in the majority of treated eyes for the entire study period.

How to cite this article: Groth SL, Greider KL, Sponsel WE. Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush. J Curr Glaucoma Pract 2015;9(3):73-76.

Intraocular pressure control after the implantation of a second Ahmed glaucoma valve

The objective of this study is to evaluate the efficacy and safety of a second Ahmed glaucoma valve (AGV) in eyes with refractory glaucoma that had undergone prior Ahmed device implantation. This multicenter, retrospective study evaluated 58 eyes (58 patients) that underwent a second AGV (model S2-n = 50, model FP7-n = 8) due to uncontrolled IOP under maximal medical therapy. Outcome measures included IOP, visual acuity, number of glaucoma medications, and postoperative complications. Success was defined as IOP <21 mmHg (criterion 1) or 30 % reduction of IOP (criterion 2) with or without hypotensive medications. Persistent hypotony (IOP <5 mmHg after 3 months of follow-up), loss of light perception, and reintervention for IOP control were defined as failure. Mean preoperative IOP and mean IOPs at 12 and 30 months were 27.55 ± 1.16 mmHg (n = 58), 14.45 ± 0.83 mmHg (n = 42), and 14.81 ± 0.87 mmHg (n = 16), respectively. The mean numbers of glaucoma medications preoperatively at 12 and 30 months were 3.17 ± 0.16 (n = 58), 1.81 ± 0.2 (n = 42), and 1.83 ± 0.35 (n = 18), respectively. The reductions in mean IOP and number of medications were statistically significant at all time intervals (P < 0.001). According to criterion 1, Kaplan-Meier survival curves disclosed success rates of 62.9 % at 12 months and 56.6 % at 30 months. According to criterion 2, Kaplan-Meier survival curves disclosed success rates of 43.9 % at 12 months and 32.9 % at 30 months. The most frequent early complication was hypertensive phase (10.3 %) and the most frequent late complication was corneal edema (17.2 %). Second AGV implantation may effectively reduce IOP in eyes with uncontrolled glaucoma, and is associated with relatively few complications.

Insertion of sequential glaucoma drainage implant in a piggyback manner

PURPOSE

This pilot study, the first of its type, was conducted to determine the clinical outcome of a sequential glaucoma drainage implant (GDI) inserted in piggyback manner, that is into the bleb of a primary GDI.

METHODS

This was a retrospective chart study with a minimum 1-year follow-up involving 16 eyes of 14 uncontrolled glaucoma patients who had previously undergone sequential GDI performed using a technique to convert a one-plate into a two-plate implant system. Surgical success was defined as intraocular pressure (IOP) <21 mm Hg with at least a 30% reduction in IOP from baseline on two consecutive follow-up visits, IOP >5 mm Hg on two consecutive follow-up visits, and neither reoperation of glaucoma nor loss of light perception vision.

RESULTS

The mean ±SD baseline IOP was 29.2±5.2 mm Hg, and the mean postoperative IOP was 17.3±3.4 mm Hg, with a mean pressure drop of 39.4±10.4% (P<0.001). Life-table analysis showed an 88% success rate after 12 months of follow-up. The mean preoperative best corrected visual acuity (BCVA) was 0.2±0.2 logMAR (Snellen equivalent 6/9.5), compared with 0.3±0.3 logMAR postoperatively (Snellen equivalent 6/12; P=0.497). Postoperative complications included a flat anterior chamber and choroidal detachment (one eye), uveitis and cataract (one eye), diplopia (one eye), and worsening of pre-existing pseudophakic bullous keratopathy (one eye).

CONCLUSIONS

In glaucoma eyes with useful vision the piggyback GDI seems to provide a significant IOP lowering with minimal complications in patients in whom an initial GDI had failed to control the IOP.

Surgical Outcomes of Additional Ahmed Glaucoma Valve Implantation in Refractory Glaucoma

PURPOSE

To evaluate the surgical outcomes of the implantation of an additional Ahmed glaucoma valve (AGV) into the eyes of patients with refractory glaucoma following previous AGV implantation.

METHODS

This study is a retrospective review of the clinical histories of 23 patients who had undergone a second AGV implantation after a failed initial implantation. Age, sex, prior surgery, glaucoma type, number of medications, intraocular pressure (IOP), visual acuity, and surgical complications were analyzed. Surgical success was defined as IOP maintained below 21 mm Hg, with at least a 20% overall reduction in IOP, regardless of the use of IOP-lowering medications.

RESULTS

Following the implantation of a second AGV, the mean IOP decreased from 39.3 to 18.5 mm Hg (52.9% reduction, P<0.001). The mean number of postoperative IOP-lowering medications administered decreased from 2.8 to 1.7 after the second AGV implantation (P<0.001). The cumulative probability of success for the procedure was 87% after 1 year and 52% after 3 years. Three patients (13.0%) experienced bullous keratopathy after the second AGV implantation. None of the patients showed any evidence of diplopia or ocular movement limitation as a result of the presence of 2 AGVs in the same eye. Prior trabeculectomy was found to be a significant risk factor for failure (P=0.027).

CONCLUSIONS

A second AGV implantation can be a good choice of surgical treatment when the first AGV has failed to control IOP.

Childhood glaucoma surgery in the 21st century

Most children with glaucoma will require surgery in their lifetime, often in their childhood years. The surgical management of childhood glaucoma is however challenging, largely because of its greater potential for failure and complications as compared with surgery in adults. The available surgical repertoire for childhood glaucoma has remained relatively unchanged for many years with most progress owing to modifications to existing surgery. Although the surgical approach to childhood glaucoma varies around the world, angle surgery remains the preferred initial surgery for primary congenital glaucoma and a major advance has been the concept of incising the whole of the angle (circumferential trabeculotomy). Simple modifications to the trabeculectomy technique have been shown to considerably minimise complications. Glaucoma drainage devices maintain a vital role for certain types of glaucoma including those refractory to other surgery. Cyclodestruction continues to have a role mainly for patients following failed drainage/filtering surgery. Although the prognosis for childhood glaucoma has improved significantly since the introduction of angle surgery, there is still considerable progress to be made to ensure a sighted lifetime for children with glaucoma all over the world. Collaborative approaches to researching and delivering this care are required, and this paper highlights the need for more high-quality prospective surgical trials in the management of the childhood glaucoma.

Second glaucoma drainage devices in refractory pediatric glaucoma: failure by fibrovascular ingrowth

PURPOSE

To evaluate initial glaucoma drainage device failure and subsequent glaucoma drainage device placement for refractory pediatric glaucoma.

DESIGN

Retrospective interventional case series.

METHODS

The Duke University surgical records from a single surgeon from 1997 to 2012 were reviewed for patients having at least 2 glaucoma drainage devices for refractory pediatric glaucoma. Data collected included glaucoma diagnosis, age at surgery, surgical interventions, preoperative/postoperative IOP and medications, and complications. Failure was defined as having an IOP >21 mm Hg (or clinically inadequate), and/or IOP-reducing surgery/devastating complication.

RESULTS

Forty-three eyes (37 patients) had 2 or more glaucoma drainage devices. Mean age at second glaucoma drainage device implantation was 9.2 ± 7.1 years, with mean IOP 30 ± 11 mm Hg, on 3 ± 1 IOP-lowering medications. Fibrovascular ingrowth was documented during second glaucoma drainage device surgery in 12 of 43 eyes (28%), occurring only in Ahmed devices, at a mean of 70 months (range 11-153) after initial implantation. Failure of the second glaucoma drainage device surgery occurred in 18 of 43 eyes (42%) at mean 26.1 ± 32.2 months (median 19.3 months). Surgical success of second glaucoma drainage devices (Kaplan-Meier analysis) at 1 year, 2 years, and 3 years was 81%, 62%, and 50%, respectively.

CONCLUSIONS

Single glaucoma drainage device surgery fails to control IOP in some eyes with refractory pediatric glaucoma. Second glaucoma drainage device implantation offers a treatment option with modest success over time. Fibrovascular ingrowth should be suspected as a relatively common cause of IOP elevation and failure after Ahmed device implantation.

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.

Simultaneous placement of 2 glaucoma drainage devices for uncontrolled glaucoma

OBJECTIVE

To report baseline characteristics and surgical outcomes of placement of simultaneous glaucoma drainage devices (GDDs) in eyes with considerably elevated intraocular pressure (IOP) despite maximal medical therapy.

DESIGN

Retrospective case series.

PARTICIPANTS

Twelve eyes of 12 patients underwent simultaneous placement of a Baerveldt 350 GDD and an Ahmed S3 GDD in the same eye.

METHODS

The medical records were reviewed of consecutive patients who underwent simultaneous placement of a Baerveldt 350 GDD and an Ahmed S3 GDD in the same eye at the University of Michigan Kellogg Eye Center from 2006 to 2009. Baseline characteristics, preoperative and postoperative IOP, number of glaucoma medications, visual acuity, and complications were recorded.

RESULTS

Mean follow-up time was 28.6 ± 22.8 months. The mean baseline cup/disc ratio was recorded at 0.94 ± 0.07 horizontally and 0.92 ± 0.09 vertically. The mean baseline IOP of 38.8 ± 6.2 mm Hg was significantly reduced at all time points postoperatively, and the mean IOP at last follow-up was 15.1 ± 4.9 mm Hg (p ≤ 0.0001). Mean number of glaucoma medications was significantly lower at last follow-up than preoperatively (1.4 ± 1.3 vs 3.2 ± 0.8; p = 0.001). There was no difference in mean logMAR visual acuity from before surgery to last follow-up (1.14 vs 1.12; p = 0.933).

CONCLUSIONS

Simultaneous placement of 2 GDDs effectively reduces IOP in the immediate postoperative period and long-term, and may be useful in glaucomatous eyes with advanced disease and considerably elevated preoperative IOP.

Efficacy of Additional Glaucoma Drainage Device Insertion in Refractory Glaucoma: Case Series with a Systematic Literature Review and Meta-Analysis

PURPOSE

To report the efficacy of additional glaucoma drainage device (GDD) insertion in eyes with refractory glaucoma and which have a failed primary GDD.

METHODS

We conducted a non-comparative, retrospective study on eight eyes of eight patients who had a failed primary GDD and received an additional GDD in the same eye. Intraocular pressure (IOP), visual acuity (VA), the number of anti-glaucomatous medications, and complications were analyzed during the most recent office visit. Success was defined as an IOP between 6 and 21 mmHg and a 20% decrease in IOP after additional GDD insertion, with or without anti-glaucomatous medication.

RESULTS

The mean decrease in IOP at the final follow-up was 19.3 mmHg (56.1%). The mean number of anti-glaucomatous medications used at the final follow-up (2.38) was significantly less than the preoperative mean (3.50). Seven patients achieved the criteria for success, whereas one patient had an unsuccessful outcome because of corneal graft failure after additional GDD insertion.

CONCLUSIONS

We showed that after the failure of a primary GDD, an additional GDD offered favorable IOP control and stable VA. In agreement with a review of previous literature, GDD insertion is the best option for treating refractory glaucoma, even in patients with a failed primary GDD.

Current surgical options for the management of pediatric glaucoma

Currently, there are numerous choices for the treatment of pediatric glaucoma depending on the type of glaucoma, the age of the patient, and other particularities of the condition discussed in this review. Traditionally, goniotomy and trabeculotomy ab externo have been the preferred choices of treatment for congenital glaucoma, and a variety of adult procedures adapted to children have been utilized for other types of pediatric glaucoma with variable results and complications. More recently, seton implantations of different types have become more popular to use in children, and newer techniques have become available including visualized cannulation and opening of Schlemm's canal, deep sclerectomy, trabectome, and milder more directed cyclodestructive procedures such as endolaser and transcleral diode laser cyclophotocoagulation. This paper reviews the different surgical techniques currently available, their indications, results, and most common complications to allow the surgeon treating these conditions to make a more informed choice in each particular case. Although the outcome of surgical treatment in pediatric glaucoma has improved significantly, its treatment remains challenging.

Long-term success of ahmed glaucoma valve in refractory glaucoma

AIM

To evaluate the long-term results and complications of ahmed glaucoma valve (AGV) implantation in refractory glaucoma.

METHODS

A retrospective review of 13 patients (13 eyes) with refractory glaucoma who underwent AGV implantation and had a minimum follow-up of 18 months was performed. All patients underwent a complete ophthalmologic examination and intraocular pressure (IOP) measurement before surgery and at 1 month, 3 months, 6 months, 1 year after surgery and yearly afterwards. Complications and the number of antiglaucoma medications needed were recorded.

RESULTS

Mean age was 27.3±16.0 years. All eyes (100%) had at least one prior incisional surgery. Mean follow-up was 61.3±30.8 months. IOP was reduced from a mean of 35.0 ±7.0mmHg to 18.2±7.9mmHg at 12 months and to 17.0±4.1mmHg at 96 months (P<0.05) with a lower number of medications from baseline, 76.9% patients required additional procedures to achieve the success criteria set by previously published series. The most common complications were encapculated cyst formation in eight eyes (61.5 %) and tube exposure in four eyes (30.8%).

CONCLUSION

Encapsulated cyst formation was the most common complication which hindered succesful IOP control after AGV implant insertion for refractory glaucoma. Despite cyst excision with anti-fibrotic agents, successful IOP reduction was not achieved in 76.9% of the patients without antiglaucoma medication.

Ahmed glaucoma valve in children: A review

Pediatric glaucoma is potentially a blinding disease. Although goniotomy and trabeculotomy are associated with good early success rates, eventually 20% of these procedures fail and many children will require additional surgery to control the IOP in the long-term. In this review, we reported that adequate IOP control can be achieved with the placement of Ahmed glaucoma valve and can last 5 or more years. However, most patients will need one or more glaucoma medications at some point after surgery. In addition, the implants may be associated with pupillary irregularities, lenticular opacification as well as tube-related complications, particularly in the first year of life, as the globe is enlarging with age.

Sequential glaucoma implants in refractory glaucoma

PURPOSE

To evaluate the efficacy of a second glaucoma implant in eyes with prior glaucoma implant surgery and inadequate intraocular pressure (IOP) control.

DESIGN

Retrospective observational cohort study.

METHODS

Patients undergoing a second glaucoma implant surgery from 1996 to 2008 were included. Outcome measures included visual acuity, IOP, glaucoma medication use, and complications. Success was defined as IOP < 21 mm Hg (criterion 1) and IOP < 17 mm Hg (criterion 2), with at least 25% reduction in IOP and no prolonged hypotony.

RESULTS

Forty-three eyes (43 patients) had a mean follow-up of 32.6 +/- 21.6 months. Life-table analysis demonstrated success rates of 93%, 89%, and 83% using criterion 1 and 83%, 75%, and 75% using criterion 2 at 1, 2, and 3 years, respectively. At last follow-up, mean IOP (13.6 +/- 4.6 vs 24.7 +/- 7.5 mm Hg; P < .001) and mean number of medications (1.4 +/- 1.2 vs 3.9 +/- 1.2; P < .001) were lower following the second implant. There was no difference in preoperative and most recent logarithm of the minimal angle of resolution (logMAR) visual acuities (0.86 +/- 0.13 vs 1.1 +/- 0.13; P = .07). The most frequently used second implants were similar in percentage IOP reduction (Baerveldt implant, 45 +/- 19%; Ahmed valve, 40 +/- 18%; P = .4).

CONCLUSIONS

A second glaucoma implant may effectively lower IOP in eyes with refractory glaucoma.

Cyclophotocoagulation versus sequential tube shunt as a secondary intervention following primary tube shunt failure in pediatric glaucoma

PURPOSE

To examine the efficacy of a sequential tube shunt versus transscleral diode cyclophotocoagulation following failure of an initial tube shunt on maximal medical therapy in treatment of refractory childhood glaucoma.

METHODS

A nonrandomized retrospective chart review was conducted of 17 eyes of 14 pediatric patients (less than 18 years old) with refractory glaucoma treated with either sequential tube shunt (Group A) or diode cyclophotocoagulation (Group B) following initial failed tube shunt. Success was defined as an intraocular pressure < or =22 mm Hg on medical therapy, no visually devastating complications, and no further glaucoma surgery performed or recommended.

RESULTS

Of the 17 eyes, 8 had a sequential tube shunt and 9 underwent diode cyclophotocoagulation as a secondary procedure. Kaplan-Meier analysis demonstrated a successful outcome of 75% and 62.5% at 12 months and 24 months, respectively, for Group A, and 66.7% at both 12 months and 24 months for Group B (p = 0.48). Corneal decompensation or graft failure was noted in 3/8 eyes (38%) in Group A. Cataract surgery was performed in 2/5 phakic eyes (40%) in Group B. One eye in each group progressed to no light perception.

CONCLUSIONS

Diode cyclophotocoagulation and sequential tube shunt following primary tube shunt failure in childhood glaucoma showed similar efficacy and complication rates. However, the small sample size of this study warrants further evaluation of these 2 procedures following failure of a tube shunt device in pediatric glaucoma.

Second Ahmed valve insertion in the same eye

PURPOSE

To examine the results of same-eye second Ahmed glaucoma drainage device (GDD) insertion in eyes with refractory glaucoma despite previous Ahmed GDD insertion and maximal tolerated medical therapy.

METHODS

Noncomparative retrospective case series.

RESULTS

Twenty-one patients who had undergone 2 GDD surgeries in the same eye were identified. Following chart review, 19 patients had follow-up of at least 1 year and were included in the analysis. All surgeries involved Ahmed valves. The mean drop in intraocular pressure (IOP) at 12 months and at final follow-up was 8 (43%) and 7.9 mm Hg (42%), respectively. The mean number of glaucoma medications used postoperatively (2.4 at 12 mo and 2.6 at final follow-up) was significantly less than preoperatively (4.1). Although the mean visual acuity was poorer postoperatively, this did not reach statistical significance. Sixteen of the 19 patients (84.2%) were defined as complete or partial success, as they achieved IOP of >/=5 and </=21 mm Hg and >/=20% decrease on preoperative IOP with or without glaucoma drops. Three patients were considered complete failures at 12 months and final follow-up. There were no significant intraoperative complications. One patient (5.3%) required anterior chamber reformation on day 1 postoperatively. One patient (5.3%) suffered a decrease in vision from 20/70 preoperatively to counting fingers postoperatively owing to corneal decompensation.

CONCLUSIONS

Second Ahmed GDD surgery seems to be a safe and effective option when IOP remains uncontrolled despite previous GDD implantation.

Migration of glaucoma drainage device extender into anterior chamber after trauma

PURPOSE

Glaucoma drainage devices, on rare occasions, need repositioned and the intraocular portion of the implant tube is found to be "too short" to do so. Previously, a technique was described for "extending" the tube with angiocatheter material (rather than replacing the entire apparatus), and had been performed successfully without complication for 7 years. This case describes the first known complication: trauma causing anterior chamber migration of the tube extension requiring retrieval and reconstruction of the tube extension apparatus.

PATIENT AND METHODS

One eye of 1 patient (age 8) with a prior glaucoma drainage device and tube extension with angiocatheter material with elevated intraocular pressure after direct trauma to the eye from a pencil. Office examination revealed inferior corneal edema and no tube segment visible in the anterior chamber on limited examination due to age-related compliance. Gonioscopy under anesthesia revealed the tube extender in the inferior anterior chamber. The tube extender was retrieved from the anterior chamber. The glaucoma drainage device was surgically exposed and the tube extension was reconstructed, including securing the tube extension with a suture placed through the lumens of both the angiocatheter extender and the tube extension.

RESULTS

The reconstructed tube extension maintained good draining function with the secured extension and no further migration of the tube extension into the anterior chamber was seen.

CONCLUSIONS

Tube extension using angiocatheter material continues to be a viable, cost-effective option in difficult cases. Placing a securing suture in patients prone to eye trauma can be considered.

Surgical outcomes of combined phacoemulsification and glaucoma drainage implant surgery for Asian patients with refractory glaucoma with cataract

PURPOSE

To examine the safety and efficacy of combined phacoemulsification and glaucoma drainage implant surgery in providing reduction of intraocular pressure (IOP) and visual rehabilitation in eyes with refractory glaucoma and cataract.

DESIGN

Interventional case series.

METHODS

A retrospective chart review was performed on all subjects who underwent combined phacoemulsification with intraocular lens implantation and glaucoma drainage implant surgery by a single surgeon at the National University Hospital, Singapore. The implants used were the 185 mm2 Ahmed glaucoma valve and the 350 mm2 Baerveldt glaucoma implant. In terms of IOP, a complete success was defined as IOP of between 6 to 21 mm Hg without medication, qualified success as IOP between 6 to 21 mm Hg with one or more medication, and failure as a sustained IOP of >21 mm Hg or <6 mm Hg with or without one or more medication on two or more visits.

RESULTS

A total of 32 combined phacoemulsification and glaucoma implant surgeries in 32 patients was performed. All patients were of Asian origin, and the mean age was 58 +/- 16 years (range, 20-78 years). The Baerveldt glaucoma implant and Ahmed glaucoma valve implant were inserted in 16 eyes each. With a mean follow-up of 13 +/- 5 months (range 6 to 22 months), IOP was reduced from a mean of 28.0 +/- 11.5 mm Hg to 15.2 +/- 6.0 mm Hg postoperatively (P <.0001), whereas the number of antiglaucoma medications decreased from a mean of 2.4 +/- 1.4 to.3 +/-.7 (P <.0001) at last follow-up. Overall, there were 24 eyes (75%) that were classified as complete successes, 4 eyes (12.5%) that were qualified successes, and 4 eyes that failed (12.5%). Twenty-three eyes (72%) had improvement of visual acuity, while only one eye had a loss of more than 1 line of Snellen acuity. There was no case that encountered an intraoperative complication, and postoperative complications occurred in 12 eyes (38%), the most common of which was hypotony (in six eyes, 19%).

CONCLUSION

For subjects with refractory glaucoma and cataract, combined phacoemulsification and glaucoma drainage implant surgery provide good visual rehabilitation and control of IOP, with low incidence of complications.

Aqueous shunt devices compared with trabeculectomy with Mitomycin-C for children in the first two years of life

PURPOSE

To compare the outcomes of children 24 months of age or younger treated with aqueous shunt devices or with mitomycin-C (MMC) trabeculectomy.

DESIGN

Retrospective, age-matched, comparative case series.

METHODS

Forty-six eyes of 32 patients with mean age of 7.0 +/- 5.1 month (range, 1 to 22 months) and uncontrolled glaucoma, which received an aqueous shunt device (Ahmed glaucoma valve or Baerveldt implant), compared with 24 eyes of 19 patients with mean age of 5.3 +/- 4.8 months (range, 0.5 to 24 months), which received an MMC trabeculectomy. Surgical success was defined as intraocular pressure < 23 mm Hg on maximal glaucoma medication, no further glaucoma surgery performed or recommended, no devastating complication, and stable ocular dimensions (axial length and corneal diameter).

RESULTS

Cumulative probabilities of success were 87% +/- 5.0% for the aqueous shunt group compared with 36% +/- 8.0% success in the trabeculectomy group at 12 months and 53% +/- 12% in the aqueous shunt group compared with 19% +/- 7% in the trabeculectomy group at 72 months (chi(2) of 23.5, P <.0001). Aqueous shunt implantation was associated with significantly more postoperative complications requiring a return to the operating room (21 of 46 eyes, 45.7%) compared with trabeculectomy with MMC (3 of 24 eyes, 12.5%, P =.0074). The most common postoperative procedure in the aqueous shunt group was tube repositioning, performed in 16 of 46 eyes (34.8%).

CONCLUSIONS

Aqueous shunt implantation offers a significantly greater chance of successful glaucoma control in the first 2 years of life, compared with trabeculectomy with MMC. However, the enhanced success with aqueous shunt devices is associated with a higher likelihood of postoperative complications requiring surgical revision, most commonly tube repositioning.

Needling revision of failed filtering blebs after trabeculectomy: a retrospective study

PURPOSE

To determine the efficacy and safety of needling revision of failed filtering blebs.

METHODS

We reviewed retrospectively 26 eyes that had undergone needling revision for a failed trabeculectomy. The needling revisions were performed either with adjunctive use of Mitomycin C, 5-Fluorouracil or without antimetabolites. The procedure was usually performed as a clinic procedure, using a 27-gauge needle.

RESULTS

The mean follow-up time was 14.5 +/- 11.3 months (range 6.0-48.0 months). Intraocular pressure (IOP) decreased from 28.8 +/- 6.8 mmHg (range 19.0-40.0 mmHg) to 15.3 +/- 5.2 mmHg (range 7.0-35.0 mmHg). Twelve eyes (46.2%) achieved success, defined as IOP < or = 18 mmHg without medication; 11 eyes (42.3%) achieved qualified success, defined as IOP < or = 18 mmHg with antiglaucomatous medication, and three of 26 eyes (11.5%) were classified as failures. The success rate after the initial needling was 64% at 6 months and the same after 1 year and 2 years. The success rate after one or more needlings was 96% at 6 months and 77% at 1 year and 2 years. Complications developed in six of the 26 eyes (23.1%). These involved transient corneal epithelial defects in three eyes (11.5%), temporary conjunctival wound leak in two eyes (7.7%), and development of bullous keratopathy in one high risk eye (3.8%).

CONCLUSION

Our results are comparable to the results of other studies. Needling revision appears to be a useful tool in the management of glaucoma.

Surgical management of patients with combined glaucoma and corneal transplant surgery

The reasons for having combined glaucoma and corneal transplant surgery are myriad. Patients with corneal transplants have a high frequency of developing secondary glaucoma. Patients with preexisting glaucoma have even higher risk for developing glaucoma refractory to medical management after penetrating keratoplasty. The indication for corneal transplant affects the risk for developing postkeratoplasty glaucoma. The surgical treatment options for treating glaucoma include laser trabeculoplasty, cycloablation, trabeculectomy, and glaucoma drainage implants. In addition, the sequencing of glaucoma surgery relative to penetrating keratoplasty affects the outcome. Newer corneal transplant techniques may have a lower risk for developing secondary glaucoma.