Surgical outcomes of a new affordable non-valved glaucoma drainage device and Ahmed glaucoma valve: comparison in the first year

Comparison of Aurolab Aqueous Drainage Implant with Ahmed Glaucoma Valve for Refractory Glaucoma: A Meta-Analysis

BACKGROUND

Ahmed glaucoma valve (AGV) is a common surgical method for the treatment of refractory glaucoma.Aurolab aqueous drainage implant (AADI) is a novel surgical method which has been applied in clinical practice in recent years.

OBJECTIVE

The purpose of this study was to compare the efficacy and safety of the AADI and the AGV for the treatment of refractory glaucoma.

METHODS

We comprehensively searched four databases, including PubMed, Embase, Web of Science, and the Cochrane Library databases, selecting the relevant studies. The continuous variables, namely, intraocular pressure reduction (IOPR) and a reduction in antiglaucoma medication (AGMR), were pooled by the weighted mean differences (WMDs), and the dichotomous outcomes, including success rates and complications, were pooled by the odds ratio (OR).

RESULTS

A total of 825 eyes from 820 patients from six studies were included. The WMDs of the IOPR between the AADI and the AGV implant were 0.58 (95% CI: 0.07-1.09) at 3 months, 0.44 (95% CI: 0.11-0.77) at 6 months, 2.20 (95% CI: 0.63-3.77) at 12 months, and 3.24 (95% CI: 1.73-4.75) at follow-up endpoint. Significant difference was detected between the two groups at any point in time. The WMDs of the AGMR between the AADI and the AGV implant were 0.87 (95% CI: 0.61-1.13) at 6 months, 1.04 (95% CI: 0.66-1.42) at 12 months, and 0.93 (95% CI: 0.52-1.34) at the follow-up endpoint; the differences reached statistical significance at any point in time. The pooled ORs comparing the AADI with the AGV were 3.64 (95% CI: 2.44-5.45) for the complete success rate and 1.72 (95% CI: 1.24-2.39) for qualified success rate; significant difference was detected between the two groups. There were no significant differences between the AADI and the AGV implant on the rates of adverse events.

CONCLUSIONS

The AADI is more effective in both its surgical success rate and reducing IOP and AGM. And the two implants may have comparable incidences of adverse events.

Safety and efficacy of Aurolab aqueous drainage implant in refractory glaucoma: A prospective study

Purpose

This study was conducted to assess the intraocular pressure (IOP) control and postoperative complications following a non-valved glaucoma drainage device (GDD) surgery in refractory glaucoma.

Methods

This was a prospective interventional study conducted on patients with glaucoma refractory to maximal medications or failed surgical treatment who underwent Aurolab aqueous drainage implant (AADI; Aurolabs, India) surgery. Primary outcome measures were IOP control, postoperative complications, and reduction in the number of antiglaucoma medications (AGM).

Results

Thirty-four eyes were analyzed and the mean follow-up was 16.06 ± 5.63 months. The preoperative median (Q1, Q3) IOP was 31 mmHg (28, 36.5) which decreased to 12 mmHg (12, 14) at 6 months postoperatively. The median (Q1, Q3) number of AGMs decreased from 3 (3, 4) to 0 (0, 1). Significant complications like implant extrusion and tube exposure were noted in two eyes. The total success and failure rates at 6 months were 91.1% and 8.8%, respectively.

Conclusion

AADI is effective in achieving target IOP and significantly reduces the use of AGMs with good safety in the short term. Long-term follow-up studies are needed to assess long-term IOP control and cost-effectiveness.

Surgical outcomes of the Aurolab aqueous drainage implant (AADI) versus the Ahmed glaucoma valve for refractory paediatric glaucoma in Middle Eastern children

Objective

The Aurolab aqueous drainage implant (AADI) has the potential advantages of less encapsulation and greater cost-effectiveness than the Ahmed glaucoma valve (AGV). The aim of this study was to compare the surgical success and outcomes of the AADI compared to the AGV in Middle-Eastern children.

Methods

A comparative retrospective study of consecutive paediatric patients in a tertiary eye hospital was undertaken. Data collected included demographics, type of glaucoma, intraocular pressure (IOP), number of anti-glaucoma medications (AGMs) and any subsequent complications or further surgeries.

Analysis

The mean IOP, number of AGMs, surgical success and number of reoperations was compared for the two groups. Surgical success at each visit was defined as IOP of ≥6 mm Hg and ≤21 mm Hg or if the reduction of IOP was ≥20% reduced from baseline.

Results

A total of 126 tube surgeries (56 eyes in AADI and 70 eyes in AGV) were performed in patients aged ≤18 years from 2014 to 2019. No difference was observed in the mean IOP between the two groups except at the first month post-operative visit. After six months, the AADI group had a consistently significant lower mean number of AGMs. At last follow-up, 21 (37.5%) eyes in the AADI group were glaucoma medication-free vs 15 (21.4%) eyes in the AGV group (pp=0.047). Kaplan-Meier analysis showed equivalent cumulative probability of success at two years of 69.9% [(45.9%–84.9%)] for AADI vs 66.8% [(53.4%–77.1%])) for the AGV, respectively. Twenty-four eyes in the AGV group needed one or more subsequent surgeries, whereas 13 eyes needed one or more surgery in the AADI group.

Conclusions

This study shows an acceptable safety profile for the AADI in children, with a rate of failure that is comparable to the AGV, but less need for glaucoma re-operation or glaucoma medication in the first post-postoperative year.

Incidence and Outcomes of Suprachoroidal Hemorrhage Following Aurolab Aqueous Drainage Implant in Adult and Pediatric Glaucoma

PRCIS

Postoperative suprachoroidal hemorrhage (PSCH) is an infrequent but devastating complication after nonvalved aqueous drainage implant surgery and demonstrated a bimodal distribution. The final outcomes of either conservative management or surgical drainage of the hemorrhage remained poor.

PURPOSE

The aim was to report the incidence and outcomes of eyes developing PSCH after undergoing Aurolab aqueous drainage implant (AADI) surgery for adult and pediatric refractory glaucomas.

MATERIALS AND METHODS

In this retrospective series, case files of all patients who underwent AADI between May 2012 and December 2019 were retrieved from an electronic database. A PSCH was defined as the presence of hemorrhagic choroidal detachment, confirmed by ultrasound B scan, occurring in a closed system in the postoperative period.

RESULTS

Of the 986 eyes that underwent AADI during the study period, 7 (0.7%), developed PSCH (95% confidence interval=0.3-1.6%). There were no differences in the preoperative parameters between those with and without PSCH. Of these, 4 were seen in pediatric eyes (4/288, 1.4%) and 3 in adult eyes (3/698, 0.4%) (P<0.01). Four eyes (57%) had PSCH in the immediate postoperative period (ie, between 24 and 48 h of AADI surgery), while the remaining 3 had onset ranging from 6 to 7 weeks after surgery. Anatomic risk factors were present in all eyes including hypotony (n=4), myopia (n=3), microcornea (n=2), microphthalmos (n=1), postvitrectomy (n=1), and staphyloma (n=1). Visual acuity improved in only 1 (14%) eye while 3 (43%) eyes developed phthisis bulbi, all in the pediatric age group.

CONCLUSIONS

PSCH is a rare complication following AADI and is seen in <1% eyes. The incidence is higher in the pediatric age group. Visual and anatomic outcomes are dismal following PSCH with globe salvage possible in only about half these eyes.

Personalising surgical treatments for glaucoma patients

Surgical treatments for glaucoma have relied for decades on traditional filtering surgery such as trabeculectomy and, in more challenging cases, tubes. Antifibrotics were introduced to improve surgical success in patients at increased risk of failure but have been shown to be linked to a greater incidence of complications, some being potentially vision-threatening. As our understanding of glaucoma and its early diagnosis have improved, a more individualised management has been suggested. Recently the term "precision medicine" has emerged as a new concept of an individualised approach to disease management incorporating a wide range of individual data in the choice of therapeutic modalities. For glaucoma surgery, this involves evaluation of the right timing, individual risk factors, targeting the correct anatomical and functional outflow pathways and appropriate prevention of scarring. As a consequence, there is an obvious need for better knowledge of anatomical and functional pathways and for more individualised surgical approaches with new, less invasive and safer techniques allowing for earlier intervention. With the recent advent of minimally invasive glaucoma surgery (MIGS) a large number of novel devices have been introduced targeting potential new sites of the outflow pathway for lowering intraocular pressure (IOP). Their popularity is growing in view of the relative surgical simplicity and apparent lack of serious side effects. However, these new surgical techniques are still in an era of early experiences, short follow-up and lack of evidence of their superiority in safety and cost-effectiveness over the traditional methods. Each year several new devices are introduced while others are withdrawn from the market. Glaucoma continues to be the primary cause of irreversible blindness worldwide and access to safe and efficacious treatment is a serious problem, particularly in the emerging world where the burden of glaucoma-related blindness is important and concerning. Early diagnosis, individualised treatment and, very importantly, safe surgical management should be the hallmarks of glaucoma treatment. However, there is still need for a better understanding of the disease, its onset and progression, the functional and structural elements of the outflow pathways in relation to the new devices as well as their long-term IOP-lowering efficacy and safety. This review discusses current knowledge and the future need for personalised glaucoma surgery.

Comparison of outcomes between Aurolab aqueous drainage implant placed in the superotemporal versus inferonasal quadrant

Aim

To determine the outcomes of Aurolab aqueous drainage implant (AADI) placed in the superotemporal versus the inferonasal quadrant in adult eyes with refractory glaucoma.

Methods

This was a retrospective study of eyes that had AADI placement and completed a minimum of 2-year follow-up. The choice of the quadrant was at the surgeon’s discretion and mainly depended on the amount of scarring and conjunctival mobility. The cumulative failure rate of the AADI was defined as intraocular pressure (IOP) >21 mm Hg or not reduced by 20% below baseline on two consecutive follow-up visits after 3 months, IOP ≤5 mm Hg on two consecutive follow-up visits after 3 months, reoperation for glaucoma or a complication, or loss of light perception vision.

Results

We included 84 eyes with AADI in the inferonasal quadrant versus 69 eyes in the superotemporal quadrant. A significant drop in IOP was seen in both groups (18.4±10.4 mm Hg in the inferonasal group vs 17.7±11.1 mm Hg in the superotemporal group; p=0.63) at 3-month follow-up and this was maintained until last follow-up. Best-corrected visual acuity, IOP, number of IOP-lowering medications and complications were similar between the two groups at all time points. The cumulative success rate at 2-year follow-up without IOP-lowering medications was 57.1% (47.1%–68.1%) in the inferonasal group and 50.7% (39.8%–63.1%) in the superotemporal group (p=0.47).

Conclusions

Inferonasal AADI placement appears to be an equally safe and effective surgical option compared with superotemporal AADI placement and may be helpful in certain clinical situations.

A preliminary comparison of the Aravind aurolab drainage implant with the Baerveldt glaucoma implant: A matched case-control study

PURPOSE

The Aurolab^® aqueous drainage implant is a low-cost alternative to the Baerveldt glaucoma implant. The aim of this study was to test the hypothesis that the two implants are comparable in terms of surgical success and safety.

METHODS

We conducted a retrospective case-control study of Aurolab aqueous drainage implant done at our institution from May 2015 and May 2017. Twenty-five consecutive patients who received an Aurolab aqueous drainage implant were matched by age and diagnosis to patients who received a Baerveldt glaucoma implant. Data were collected pre-operative and post-operative visits, including visual acuity and intraocular pressure, number of medications, and complications. Surgical success was defined as intraocular pressure between 5 and 21 mmHg with a minimum 20% reduction from baseline, without loss of light perception or the need for further glaucoma surgery. Cox regression analysis was used to predict factors associated with surgical success.

RESULTS

The median (interquartile range, IQR) intraocular pressure at 1 year was 16.0 (8.0) mmHg for the Baerveldt glaucoma implant and 13.0 (8.0) mmHg for the Aurolab aqueous drainage implant, p = 0.38. Success (mean ± SE) at 1 year for the intraocular pressure >21-mmHg failure criterion was 65% ± 15% for the Baerveldt glaucoma implant and 79% ± 11% for the Aurolab aqueous drainage implant (p = 0.80). The frequency of complications listed was similar for the two groups (Fisher's exact p = 0.71). In the Cox regression, the type of implant was not found to be associated with surgical success.

CONCLUSIONS

Our preliminary results suggest that the Aurolab aqueous drainage implant is comparable to the Baerveldt glaucoma implant. Further long-term data in a larger population are needed to confirm these findings.

Outcome of a Low-Cost Glaucoma Implant versus the Baerveldt Glaucoma Implant for Paediatric Glaucoma in a Tertiary Hospital in Egypt

Purpose

To compare safety and efficacy between a low-cost glaucoma drainage device (GDD), the Aurolab aqueous drainage implant (AADI), and the Baerveldt glaucoma implant (BGI) in refractory childhood glaucoma in Egypt.

Methods

This is a retrospective study of patients who received either an AADI or BGI at a tertiary care postgraduate teaching institute. Children aged <16 years with uncontrolled intraocular pressure (IOP) with or without prior failed trabeculectomy who completed a minimum 6-month follow-up were included. The outcome measures were IOP reduction from preoperative values and postoperative complications.

Results

Charts of 57 children (younger than 16 years old) diagnosed with refractory childhood glaucoma were included. Of these, 27 eyes received AADI implants (group A), while 30 received BGI implants (group B). The mean preoperative baseline IOP was 34 ± 5 mmHg in group A versus 29 ± 2 mmHg in group B (p=0.78) in patients on maximum allowed glaucoma medications. In group A versus group B, the mean IOP decreased to 13.25 ± 8.74 mmHg (p=0.6), 12.8 ± 5.4 mmHg (p=0.7), and 12.6 ± 5.6 mmHg (p=0.9) after 1 week, 3 months, and 6 months, respectively. However, in group A, an anterior chamber reaction appeared around the tube in 14 cases starting from the first month and resolved with treatment in only 4 cases. In the other 10 cases, the reaction became more severe and required surgical intervention. This complication was not observed in any eye in group B.

Conclusion

AADI, a low-cost glaucoma implant, is effective in lowering IOP in patients with recalcitrant paediatric glaucoma. However, an intense inflammatory reaction with serious consequences developed in some of our patients; we believe these events are related to the valve material. We therefore strongly recommend against its use in children.

Intermediate-term outcomes of Aurolab aqueous drainage implant in refractory paediatric glaucoma

Aim

To report the intermediate-term outcomes of Aurolab aqueous drainage implant (AADI) surgery in paediatric eyes with refractory glaucoma.

Methods

Case records of patients below 18 years, who underwent AADI surgery between 2012 and 2015 with >2 years follow-up, were analysed. The intraocular pressure (IOP), visual acuity, number of antiglaucoma medications, complications and resurgery if any were recorded at baseline, day 1and then at months 1, 3, 6, 9, 12, 18, 24 and at the last visit. Failure was defined as IOP >18 mm Hg or not reduced by at least 30% below baseline, IOP ≤5 mm Hg on two consecutive follow-up visits after 3 months, reoperation for a complication or loss of light perception vision.

Results

101 eyes of 101 patients were included with a mean age of 10.4±4.7 years at the time of surgery and a mean follow-up of 40.9±15.1 months. Glaucoma following cataract surgery was the most common type of glaucoma (n=31, 30%), followed by primary congenital glaucoma (n=29, 29%). The cumulative probability of failure was 15.8% (95% CI 10.1% to 24.5%) at 1 year, 22.7% (95% CI 15.7% to 32.2%) at 2 years, 42.5% (95% CI 32.6% to 53.9%) at 3 years and 62.1% (95% CI 49.5% to 74.8%) at the 4 years time point.

Conclusion

The AADI showed excellent success until 2 years after surgery in paediatric eyes after which failure rates increased. Further prospective studies with longer follow-up are required to evaluate the long-term success of the AADI for paediatric glaucomas.

Long-term outcome of low-cost glaucoma drainage device (Aurolab aqueous drainage implant) compared with Ahmed glaucoma valve

Purpose

To compare the long-term outcome of Aurolab aqueous drainage device (AADI) and Ahmed glaucoma valve (AGV).

Method

Retrospective analysis of patients with refractory glaucoma who underwent AGV (AGV-FP7) and AADI (AADI Model 350) implantation. The outcome measures were intraocular pressure (IOP), requirement of antiglaucoma medications (AGMs) and re-surgery for IOP control. The postoperative complications were classified as early (≤3 months), intermediate (>3 months to ≤1 year) or late (>1 year).

Results

173 patients (189 eyes) underwent AGV implantation (AGV Group) while 201 patients (206 eyes) underwent AADI implantation (AADI group). The IOP in AADI group was significantly lower than AGV group at all time points till 2 years and comparable at 3 years. AADI group had significantly higher number of AGM in preoperative period and significantly lower number in postoperative period till 3 years compared with AGV group. AADI group had more hypotony-related complications but statistically insignificant (p = 0.07). The surgical interventions were significantly higher in AGV (n = 18) compared with AADI group (n = 5) in late postoperative period (p = 0.01). At 3 years, overall success was seen in 58.18% in AGV and 73.08% in AADI group (p = 0.15). Complete success was seen in 7.27% patients in AGV and 25.00% patients in AADI group (p = 0.02).

Conclusion

Both AADI and AGV implant had comparable mean IOP at 3 years with lesser requirement of AGM in the AADI group. Both procedures appear to be safe with slight preponderance of hypotony-related complications in AADI group.

A novel simplified method for managing inadvertent tube cut during aurolab aqueous drainage implant surgery for refractory glaucoma

We report a novel simplified method for managing inadvertent tube cut in a patient undergoing the Aurolab aqueous drainage implant (AADI) surgery for refractory neovascular glaucoma. Tube cut occurred while applying the polyglactin ligature suture used to avoid early postoperative hypotony. The short end of the cut tube was removed and the long end reinserted into the base plate of AADI. The surgery was then completed as usual. Following the surgery, the intraocular pressure reduced to 20 mmHg which stabilized and was maintained at 10 mmHg till the last follow-up at 12 months without any glaucoma medication.

Efficacy of Ahmed Glaucoma Valve Implantation on Neovascular Glaucoma

To evaluate the efficacy of Ahmed glaucoma valve (AGV) implantation in treating neovascular glaucoma (NVG) and analyze the factors influencing the surgical success rate, a retrospective investigation of 59 NVG patients (66 eyes) who underwent AGV implantation was conducted at Jiangsu Province Hospital, China, from January 2014 to June 2018. Intraocular pressure (IOP), visual acuity, surgical success rates, medications, and complications were monitored at post-operative 1 day, 1 week, 1, 3, 6 and 12 months. Surgical success criteria were defined as 6 mm Hg < IOP < 21 mmHg with or without additional medications. Results showed average IOP was statistically significant between pre-operative visit and each follow-up visit (all P<0.05). At 12 months, the success rate was 66.7%. Multiple stepwise regression analysis suggested that age, panretinal photocoagulation (PRP), complications and hyphema were significant factors influencing the surgical success rate (all P<0.05). Thus, we conclude that AGV implantation is effective and safe for treatment of NVG. Surgical success is dependent on age, PRP, complications, and hyphema.