Complications and 2-year valve survival following Ahmed valve implantation during the first 2 years of life

Long-term surgical outcomes of Aurolab aqueous drainage implant in pediatric eyes with primary congenital glaucoma versus aphakic glaucoma

PURPOSE

To compare the outcomes of the Aurolab aqueous drainage implant (AADI) placed in eyes with refractory primary congenital glaucoma (PCG) versus aphakic glaucoma (APG).

DESIGN

Retrospective comparative interventional case series.

METHODS

Case files of consecutive eyes with PCG or APG that underwent AADI surgery between January 2013 and December 2016 and had a minimum 4 years follow-up were extracted from a computerised database. Failure was defined as intraocular pressure (IOP)>21 mm Hg or reduced<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.

RESULTS

Eighty-nine eyes underwent AADI placement, including 42 eyes (47%) with PCG and 47 eyes (53%) with APG. Both groups were comparable at baseline. At 1 year, the APG group had lower mean IOP (13.6±8.1 mm Hg vs 17.6±7.5 mm Hg, p=0.02) with use of fewer IOP-lowering medications (0.8±1.0 vs 1.5±1.0, p=0.01) than the PCG group. The cumulative failure rate at 4 years was 57% (95% CI 43% to 72%) in PCG versus 40% (95% CI 28% to 56%) in the APG eyes (p=0.11). Eyes with PCG had greater tube-related complications (48% vs 38%, p=0.07) and number of reoperations (40% vs 32%, p=0.02) compared with eyes with APG.

CONCLUSIONS

Eyes with APG had relatively better outcomes after AADI placement compared with PCG during 4 years of follow-up. Reoperations accounted for more than 70% of the failures.

Efficacy of Ahmed and Baerveldt glaucoma drainage device implantation in the pediatric population: A systematic review and meta-analysis

Glaucoma drainage devices (GDD) are increasingly utilized in the management of childhood glaucoma. This systematic review and meta-analysis assesses the efficacy of first-time Ahmed or Baerveldt implantation in children. PubMed, Embase, and Cochrane Library were searched for relevant English-language, peer-reviewed literature. Postoperative outcomes were pooled using random effects regression models with restricted maximum likelihood estimation. Thirty-two studies (1,221 eyes, 885 children) were included. Mean ± standard deviation preoperative IOP was 31.8 ± 3.4 mm Hg. Pooled mean IOP at 12 and 24 months postoperatively were 16.5 mm Hg (95% CI, 15.5-17.6) and 17.6 mm Hg (95% CI, 16.4-18.7), respectively. Pooled proportions of success were 0.87 (95% CI, 0.83-0.91) at 12 months, 0.77 (95% CI, 0.71-0.83) at 24 months, 0.54 (95% CI, 0.44-0.65) at 48 months, 0.60 (95% CI, 0.48-0.71) at 60 months, and 0.37 (95% CI, 0.32-0.42) at 120 months. There were no differences in proportion of success at 12 and 24 months among eyes that received Ahmed and Baerveldt tube shunts, nor between eyes with primary glaucoma, glaucoma following cataract surgery, or other secondary glaucoma. Our findings show that Ahmed and Baerveldt shunts substantially reduced IOP for at least 24 months in childhood glaucoma, with similar findings among device types and glaucoma etiologies.

Pediatric Glaucoma-From Screening, Early Detection to Management

Pediatric glaucoma (PG) covers a rare and heterogeneous group of diseases with variable causes and presentations. Delayed diagnosis of PG could lead to blindness, bringing emotional and psychological burdens to patients' caregivers. Recent genetic studies identified novel causative genes, which may provide new insight into the etiology of PG. More effective screening strategies could be beneficial for timely diagnosis and treatment. New findings on clinical characteristics and the latest examination instruments have provided additional evidence for diagnosing PG. In addition to IOP-lowering therapy, managing concomitant amblyopia and other associated ocular pathologies is essential to achieve a better visual outcome. Surgical treatment is usually required although medication is often used before surgery. These include angle surgeries, filtering surgeries, minimally invasive glaucoma surgeries, cyclophotocoagulation, and deep sclerectomy. Several advanced surgical therapies have been developed to increase success rates and decrease postoperative complications. Here, we review the classification and diagnosis, etiology, screening, clinical characteristics, examinations, and management of PG.

Risk Factors for Glaucoma Drainage Device Exposure in Children: A Case-Control Study

PURPOSE

To identify the risk factors for glaucoma drainage device (GDD) exposure in children.

DESIGN

Retrospective case-control study.

METHODS

The study population comprised children (one eye each) who presented with a history of GDD exposure to a tertiary care eye hospital over the period January 2014 to January 2020. Consecutive children (age <18 years) were included. A control group from the same time period (children without GDD exposure) were included in the ratio of 5 controls to every 1 case of exposure. The main outcome measures included risk factors for exposure (univariate and multivariate analysis).

RESULTS

A total of 21 eyes (of 21 children with implant exposure) and 115 eyes (of 115 children without exposure) were included in this study. During the same study period, a total of 494 eyes had undergone GDD implantation, giving an estimated incidence of exposure of 4.25%). In the bivariate analysis, GDD exposure was associated with multiple previous ocular surgeries (P = .001), longer follow-up duration (P < .001), combined procedure at the time of primary implantation (P = .002), and a younger age at the time of primary implantation (P = .006). The former 3 risk factors continued to prove a statistically significant association on multivariable regression analysis. Postoperative use of eye lubricants was more common among children in the control group (P = .007).

CONCLUSION

In pediatric glaucoma patients, younger age and combined procedure at the time of primary GDD implantation, in addition to multiple previous ocular surgeries, were associated with greater risk of implant exposure. Postoperative use of eye lubricants may be protective.

Outcomes of Ahmed glaucoma valve implantation in pediatric glaucoma

BACKGROUND: In many types of pediatric glaucoma, there is no clear algorithm for surgical management. In these situations, the procedure of choice can be the implantation of various types of drainage devices. AIM: To evaluate the outcomes of Ahmed Glaucoma Valve implantation in refractory pediatric glaucoma. MATERIALS AND METHODS: The treatment results of 52 children (67 eyes) aged 1 month 17 years (6.6 0.6 years) with unsuccessfully operated primary congenital glaucoma, with glaucoma associated with congenital anomalies of the eyeball, with secondary glaucoma were analyzed. The surgery was considered to be effective when stable intraocular pressure (IOP) was achieved, there were no complications, and no need for repeated interventions. RESULTS: The effect of surgery was maintained for 6 months in 97% of patients, but after 1, 2 and 3 years it decreased to 91.8%, 82%, and 73.9%, respectively, and to 42.8% after 7 years. Postoperative complications included filtering bleb encapsulation (25.3%), iris retraction to the tube with pupil dislocation (4.5%); ciliochoroidal detachment (4.5%); cataract (3.0%), conjunctival erosion with tube eruption (4.5%), endophthalmitis (1.5%), retinal detachment (6.0%), tube retraction (1.5%), hyphema (3.0%). The risk factors for an unfavorable outcome of the procedure were: an increase in the anteroposterior axis of the eyeball length by 20% or more compared to the age norm, IOP at the time of the surgery higher than 32 mm Hg, as well as previous antiglaucoma filtering procedures. CONCLUSIONS: The implantation of the drainage device Ahmed Glaucoma Valve is indicated for refractory pediatric glaucoma in case of ineffectiveness of previous surgeries. However, it is necessary to take into account the decrease in the effectiveness of the device over time, which, combined with the possibility of complications, requires long-term follow-up of patients.

Clinical Outcomes After Ahmed Glaucoma Valve Implantation for Pediatric Glaucoma After Congenital Cataract Surgery

PRCIS

Ahmed valve success for glaucoma following congenital cataract surgery lasts at least 5 years in most eyes, and >10 years in some cases. The procedure is a valuable option for these patients.

PURPOSE

The aim of the study was to report on the results of Ahmed valve implantation in children with glaucoma following congenital cataract surgery.

PATIENTS AND METHODS

Medical records were reviewed for 41 pediatric eyes (27 patients) with glaucoma after congenital cataract surgery with Ahmed glaucoma valve (AGV) implantation between 2007 and 2018. The primary outcome measure was surgical success, defined as intraocular pressure (IOP) ≤22 mm Hg (with or without glaucoma medications) on 2 consecutive follow-up visits, without glaucoma reoperation, and without significant visual complications during the follow-up period.

RESULTS

Median age at the time of AGV implantation was 80 months (range: 14 to 146 mo) and the mean follow-up period was 61.1±46.5 months. The cumulative probability of surgical success was 95.1%, 89.8%, 83.1%, and 72.6% at 12, 24, 60, and 84 months, respectively. IOP significantly decreased from 35.8±7.4 mm Hg before valve implantation to 18.7±6.5 mm Hg at the last recorded visit (51.4% decrease; P<0.0001). Most eyes (79%) required medications for pressure control. Complications occurred in 14 eyes (34%), with 12 of these remaining successful. Early hypotony was the most common complication (19.5%). Retinal detachment occurred in 1 eye.

CONCLUSIONS

Despite a decrease in surgical success over time, AGV implantation was successfully used for IOP control in the majority of our pediatric eyes with glaucoma after congenital cataract surgery. Most complications were managed effectively and surgical success was maintained.

Incidence and outcome of suprachoroidal hemorrhage associated with pediatric glaucoma surgery

PURPOSE

To report the incidence and outcomes of suprachoroidal hemorrhage (SCH) associated with pediatric glaucoma surgery.

METHOD

The medical records of pediatric patients (<18 years of age) who had undergone glaucoma surgery and developed SCH from June 2014 to September 2017 were reviewed retrospectively. In all cases, the SCH was suspected clinically and was confirmed by B-scan ultrasound. Baseline characteristics, intraoperative details (including surgery type), and subsequent and final outcomes were extracted from the records.

RESULTS

Of 2,656 glaucoma surgeries during the study period, 17 cases of SCH were documented, for an overall incidence of 0.64%. Of the 17 cases, 16 occurred postoperatively, and 1 was noted intraoperatively. By surgery type, the incidence of SCH was highest for trabeculectomy (4/121), followed by glaucoma drainage device surgery (6/463), deep sclerectomy (6/851), and transcleral cyclophotocoagulation (1/542). Four children had received prior transcleral cyclophotocoagulation, and 5 of the children were aphakic at the time of the glaucoma surgery. At a mean final follow-up of 1.71 ± 1.08 years), visual acuity in the affected eye was 20/50 or better in 3 children, between 20/50 and 20/200 in 5 children, and counting fingers or worse in 9 children.

CONCLUSIONS

In our study cohort, the overall incidence of SCH associated with glaucoma surgery was 0.64%. Further study of risk factors for SCH associated with glaucoma surgery in children is needed.

Gonioscopy-assisted Transluminal Trabeculotomy in a Pediatric Patient With Steroid-induced Glaucoma

PURPOSE

To report a case of successful intraocular pressure (IOP) reduction after a 360-degree gonioscopy-assisted transluminal trabeculotomy (GATT) using the iTrack catheter in a patient with steroid-induced glaucoma as a result of treatment of vernal keratoconjunctivitis (VKC).

MATERIALS AND METHODS

Case report.

RESULTS

An 8-year-old male individual with a long-standing history of VKC, treated with topical steroids, developed elevated IOP and glaucoma in the right eye despite maximum topical glaucoma therapy. Reducing the steroid was not a viable option given the severity of VKC. A 360-degree GATT was successfully performed and IOP has been maintained off all glaucoma drops.

CONCLUSIONS

GATT is a viable option for steroid-induced glaucoma in the pediatric population. This obviates the need for riskier, more invasive conjunctival-based procedures.

The use of irradiated corneal patch grafts in pediatric Ahmed drainage implant surgery

PURPOSE

To describe the use of irradiated cornea for scleral reinforcement in Ahmed glaucoma valve drainage implant (AGV) devices in children.

METHODS

The medical records of patients <18 years of age who underwent AGV surgery with irradiated cornea as scleral reinforcement were reviewed retrospectively. The primary outcome measure was erosion of the drainage tube through the corneal patch graft. Secondary outcome measures included other major complications: persistent inflammation, wound dehiscence, transmission of infectious disease, endophthalmitis, and tube/plate self-explantation.

RESULTS

A total of 25 procedures (20 patients) met inclusion criteria. Average patient age was 70 months (range, 2 months to 17 years). Mean follow-up was 24.8 months (range, 6 months to 6.2 years). One tube experienced conjunctival exposure through two separate corneal grafts (2/25 cases [8%]), sequentially in the same eye. The first event occurred at month 3.5 after primary implantation of the tube shunt; the second erosion occurred following revision of the existing implant at month 1.5 postoperatively. There were 2 cases of auto-explantation, 2 cases of wound dehiscence, and 1 case of persistent inflammation. There were no cases of endophthalmitis or other infections.

CONCLUSIONS

To our knowledge, this is the first report describing the use of corneal patch grafts in children. Irradiated cornea improves cosmesis and enhances visualization of the tube. The risk of tube exposure was found to be low and comparable to other materials used as a patch graft.

Outcomes of Ahmed glaucoma valve implantation in advanced primary congenital glaucoma with previous surgical failure

Purpose

The purpose of this study was to evaluate the intermediate surgical results of Ahmed glaucoma valve (AGV) implantation in patients less than 7 years of age, with advanced primary congenital glaucoma who have failed previous surgeries.

Patients and methods

Consecutive patients with advanced primary congenital glaucoma that failed previous operations and had undergone subsequent AGV implantation were evaluated retrospectively. Surgical success was defined as 1) intraocular pressure (IOP) ≥6 and ≤21 mmHg; 2) IOP reduction of at least 30% relative to preoperative values; and 3) without the need for additional surgical intervention for IOP control, loss of light perception, or serious complications.

Results

Fourteen eyes of eleven patients were studied. Preoperatively, the average axial length was 27.71±1.52 (25.56–30.80) mm, corneal diameter was 14.71±1.07 (13.0–16.0) mm, cup-to-disc ratio was 0.95±0.04 (0.9–1.0), and IOP was 39.5±5.7 (30–55) mmHg. The mean follow-up time was 18.29±10.96 (5–44, median 18) months. There were significant reductions in IOPs and the number of glaucoma medications (P<0.001) postoperatively. The IOPs after operation were 11.3±3.4, 13.6±5.1, 16.3±2.7, and 16.1±2.6 mmHg at 1 month, 6 months, 12 months, and 18 months, respectively. Kaplan–Meier estimates of the cumulative probability of valve success were 85.7%, 71.4%, and 71.4% at 6, 12, and 18 months, respectively. Severe surgical complications, including erosion of tube, endophthalmitis, retinal detachment, choroidal detachment, and delayed suprachoroidal hemorrhage, occurred in 28.6% cases.

Conclusion

AGV implantation remains a viable option for patients with advanced primary congenital glaucoma unresponsive to previous surgical intervention, despite a relatively high incidence of severe surgical complications.

A Surgical Approach to Pediatric Glaucoma

Glaucoma in children differs from adult-onset disease and typically requires surgical intervention. However, affected children exhibit a spectrum of disease severity and prospective data guiding the choice of operation are lacking. This article reviews common procedures and a surgical approach to pediatric glaucoma.

Results of Ahmed glaucoma valve implantation in primary congenital glaucoma

PURPOSE

To evaluate the outcome of Ahmed glaucoma valve (AGV) implantation in primary congenital glaucoma (PCG).

METHODS

The medical records of patients with PCG refractory to trabeculotomy and medical therapy who had undergone AGV implantation with a minimum follow-up of 6 months were retrospectively reviewed. The primary outcome measure was cumulative probability of success, defined as intraocular pressure (IOP) of 6-21 mm Hg, with or without medication, and no serious complications, additional glaucoma surgery, or loss of light perception.

RESULTS

A total of 33 eyes of 22 children with a mean age (and standard deviation) of 2.7 ± 3.1 years were included. The patients had a mean follow-up time of 32.6 ± 18.3 months. The mean IOP was 32.8 ± 7.3 mm Hg preoperatively and 16.8 ± 4.0 mm Hg postoperatively. The number of glaucoma medications was 2.5 ± 0.7 preoperatively and 2.2 ± 0.7 postoperatively. The cumulative probability of success (and standard error) was 97% ± 3.0% in the 1st year, 85% ± 7.0% in the 2nd year, and 56% ± 14.8% in the 5th year. When only the first operated eye per patient was included, the cumulative probability of success was 96% ± 4.4% in the 1st and the 2nd years and 72% ± 15.3% in the 5th year. Major complications comprised tube-endothelial touch (3 eyes), cataract (2 eyes), shunt extrusion (1 eye), and retinal detachment (1 eye).

CONCLUSIONS

AGV implantation in patients with PCG offers moderate success in controlling the IOP with a low rate of complications. Most continued to require medications.

Intravitreal bevacizumab and Ahmed glaucoma valve implantation in patients with neovascular glaucoma

AIM

To explore the efficacy of preoperative intravitreal bevacizumab (IVB) injection combined with Ahmed glaucoma valve (AGV) implantation in the treatment of neovascular glaucoma (NVG).

METHODS

This retrospective study included 35 eyes from 35 patients who underwent preoperative IVB and AGV implantation for treatment of NVG. Findings such as intraocular pressure (IOP) number of anti-glaucoma medications, visual acuity (VA), surgical success rates, and complications were recorded.

RESULTS

After AGV implantation, IOP was 18.2±4.0 mm Hg, 15.5±3.3 mm Hg and 9.8±2.6 mm Hg at 6, 12 and 36mo, significantly decreased compared with pre-IOP (P<0.01). The number of anti-glaucoma medications was 0.9±0.5, 0.8±0.9 and 0.8±0.6 at 6, 12 and 36mo, significantly decreased compared to pre-treatment (P<0.01). At last visit, there were 19 eyes with stable VA, 4 with VA improvement, 12 with diminished VA and 3 with complete loss light perception. There were 7 cases that failed during 3-year fellow up period. Cumulative probabilities of valve survival by Kaplan-Meier analysis were 82.9%, 74.1% and 71.0% at 12, 24 and 36mo, respectively. Cox stepwise regression analysis found that the survival time was significant associated with the pre-visual acuity <2/400 (P<0.05). Post-operative complications occurred in 8 eyes, of which hyphema presented in 2 eyes, choroidal effusion in 2 eyes.

CONCLUSION

The procedure of preoperative IVB and AGV implantation should be one of treatments for NVG because of its safety and effectiveness.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Serial intracameral visualization of the Ahmed glaucoma valve tube by anterior segment optical coherence tomography

PURPOSE

To investigate serial changes of the Ahmed glaucoma valve (AGV) implant tube in the anterior chamber by anterior segment optical coherence tomography (AS-OCT).

METHODS

Patients who had received AGV implantation without complications (n=48) were included in this study. Each patient received follow-up examinations including AS-OCT at days 1 and 2, week 1, and months 1, 3, 6, and 12. Tube parameters were defined to measure its length and position. The intracameral length of the tube was from the tip of the bevel-edged tube to the sclerolimbal junction. The distance between the extremity of the tube and the anterior iris surface (T-I distance), and the angle between the tube and the posterior endothelial surface of the cornea (T-C angle) were defined. Factors that were related to tube parameters were analysed by multiple regression analysis.

RESULTS

The mean change in tube length was -0.20 ± 0.17 mm, indicating that the tube length shortened from the initial inserted length. The mean T-I distance change was 0.11 ± 0.07 mm and the mean T-C angle change was -6.7 ± 5.6°. Uveitic glaucoma and glaucoma following penetrating keratoplasty showed the most changes in tube parameters. By multiple regression analysis, diagnosis of glaucoma including uveitic glaucoma (P=0.049) and glaucoma following penetrating keratoplasty (P=0.008) were related to the change of intracameral tube length.

CONCLUSIONS

These results suggest that the length and position of the AGV tube changes after surgery. The change was prominent in uveitic glaucoma and glaucoma following penetrating keratoplasty.

[Glaucoma surgery in childhood]

Technical characteristics and a long-term therapeutic strategy due to a long life expectancy play a key role in pediatric glaucoma surgery. The well-established angle surgery (goniotomy and trabeculotomy) achieves successful results in primary childhood glaucoma. Trabeculectomy seems to have been displaced as a secondary approach by glaucoma drainage devices (GDD) in primary childhood glaucoma due to inferior results, especially for children under 3 years of age. Even for secondary childhood glaucoma the results of GDD are encouraging, especially for therapy refractory aphakic glaucoma. In the first 2 years after GDD surgery success rates are about 80% for pediatric glaucoma and the results appear to be independent of the type of glaucoma and implant used. The complications of GDD are balanced to the faster intraocular pressure (IOP) control during the phase of visual acuity development. Cyclodestructive procedures may be applied as a secondary adjuvant approach but they increase the risk of conjunctival scarring and hypotony for subsequent procedures.