Risk Factors for Earlier Reexposure of Glaucoma Drainage Devices

Aqueous shunt exposure repair: outcomes and risk factors for recurrence

OBJECTIVE

To investigate the outcomes of aqueous shunt exposure repair and to identify risk factors for recurrent exposure after surgical repair.

METHODS

This is a retrospective interventional case series of consecutive patients who underwent repair of an exposed aqueous shunt. Demographic and clinical data were extracted from the patients' records and survival analysis was employed to determine the probability of survival of the repair without further exposure. Cox proportional regression analysis was utilised to identify potential risk factors for failure of the repair surgery.

RESULTS

Seventy-six eyes of 76 patients were included in the study. The probability of survival without further exposure was 76.2% (CI 66.9-86.8%), 72.7% (CI 62.8-84.1%) and 54.7% (40.5-73.7%) at 1,2 and 4 years, respectively. No eye in which the tube was repositioned in the anterior chamber or in the sulcus (n = 9; 11.8%) developed a recurrence of the exposure. A shorter interval from the time of tube insertion to the repair surgery (HR 2.87 [CI 1.11-7.39]; p = 0.03; reference longer interval), a history of previous surgical revision (HR 3.06 [1.15-8.12]; p = 0.02; reference no prior revision) and the use of a human pericardial donor patch at the time of revision (HR 3.43 [1.16-10.13]; p = 0.03; reference other than pericardium) was associated with an increased risk of exposure recurrence.

CONCLUSION

Aqueous shunt exposure revision is associated with reasonable mid and long term success. A shorter interval from tube insertion to exposure revision, previous revisions and the use of a human pericardium patch were associated with increased risk of failure.

Social determinants of health and health disparities in glaucoma: A review

Social determinants of health and barriers to care can significantly impact patients' access to glaucoma care and treatment, resulting in disparities within disease presentation, progression, management, and treatment outcomes. The widespread adoption of electronic health record systems has allowed researchers and clinicians to further explore these relationships, identifying factors such as race, ethnicity, and socioeconomic status to be risk factors for more severe disease and lower treatment adherence. These disparities highlight potential targets for interventions to combat these disparities and improve overall patient outcomes. This article provides a summary of the available data on health disparities within glaucoma disease presentation, progression, management, treatment, and outcomes and discusses interventions to improve care delivery and outcomes among patients with glaucoma.

The Success Rate of Glaucoma Drainage Device Revision

PRCIS

We report the survival of surgical revision to glaucoma drainage devices for several indications in a large cohort of patients, with an overall success rate of 45% at 36 months.

PURPOSE

To evaluate the outcomes of surgical revision for complications of glaucoma drainage devices.

METHODS

Three hundred thirty-five eyes of 318 patients who underwent tube revision or removal at University of California Los Angeles (UCLA) Jules Stein Eye Institute between 1997 and 2019 were included. The pre-defined primary outcome measure was surgical success of the initial revision, defined as resolution of the condition with no additional revisions required, no functionally significant change in vision, and no instances of intraocular pressure > 21 mmHg at 2 consecutive visits postoperatively. Kaplan-Meier survival analysis was applied to evaluate survival at 36 months based on these criteria. The Wilcoxon paired test was used to compare mean preoperative and postoperative intraocular pressure, medication usage, and visual acuity.

RESULTS

Overall, survival of revised tubes at 36 months was 45%. The 4 most common indications for revision were exposure of the implant (42% of all revisions), occlusion (14%), corneal failure or threat of failure (12%), and hypotony (11%). Survival at 36 months for each of these indications was 44%, 45%, 52%, and 37%, respectively.

CONCLUSIONS

These results suggest that eyes with glaucomatous damage with long-term glaucoma drainage device complications can still have a reasonably successful outcome when a revision is performed. However, with substantial rates of vision loss and a frequent need for additional revisions to manage complications, managing patient expectations for success and making them aware of the likelihood of additional surgeries or failure is important.

Tube Revision Outcomes for Exposure with Different Repair Techniques

Purpose

The aim of this study was to report our experience with eyes that presented with an initial GDD exposure and their subsequent outcome in terms of re-exposure.

Methods

A retrospective review of charts of 42 patients (43 eyes) who presented with a GDD exposure during the period 2008–2015 in a tertiary eye care center was performed. Demographic data, past ocular history, pre-operative and post-operative information including the surgical technique of GDD surgery and exposure repair were recorded. The patients were followed for further exposure to the date of the last follow-up clinic visit. For each type of repair technique, details were collected on risk and timing of GDD exposure. The baseline features of eyes that had further exposure after initial exposure were compared to eyes without further exposure.

Results

Forty-three eyes were identified which had repair after an initial exposure. The mean ± SD age was 54 ± 27 years. Of the GDDs, Ahmed FP7 was performed in 31 eyes, Ahmed FP8 in two eyes, Ahmed S2 in five eyes, Krupin valve in two eyes and Baerveldt 350 GDD in three eyes. The methods of repair and the relative risk [95% CI] of re-exposure were: conjunctival closure only (n=4; RR=2.10 [0.84–5.23]); repair with patch graft and conjunctival repair (n=18), RR=1.24 [0.51–3.01]; tube repositioning, use of patch graft and conjunctival repair (n=14), RR=1.0; tube removal with replacement in a different quadrant, patch graft and conjunctival repair (n=3), RR=1.87 [0.64–5.48]. After the first exposure, 18 eyes had a second re-exposure, four eyes had a third re-exposure, and 1 eye had a fourth exposure.

Conclusions

The GDD exposure rates at our institution are consistent with other reports. Lack of a patch graft for repair is associated with a two-fold risk of subsequent re-exposure.

Recurrent Tube Erosions with Anti-Vascular Endothelial Growth Factor Therapy in Patients with Age-Related Macular Degeneration

PURPOSE

To determine the rates of primary and recurrent glaucoma tube shunt erosions in patients with age-related macular degeneration (AMD) receiving anti-vascular endothelial growth factor (VEGF) intravitreal injections.

DESIGN

Retrospective case series.

PARTICIPANTS

Patients with AMD who underwent tube revision for erosion at the Duke Eye Center from January 1, 1999, to January 1, 2019, were identified. Patients with and without anti-VEGF injections were compared.

METHODS

Patient demographics, ocular diagnoses, glaucoma tube shunt types and locations, and dates of glaucoma surgeries and anti-VEGF injections were collected. Statistical analyses were performed with P < 0.05 as significant.

MAIN OUTCOME MEASURES

Outcome measures included the number of tube erosions, time from anti-VEGF injection to tube erosion, and secondary complications after tube revisions.

RESULTS

A total of 150 patients with AMD with anti-VEGF (309 tubes) and 262 patients with AMD without anti-VEGF (459 tubes) were identified. There was no statistically significant difference in the number of tube erosions in patients with anti-VEGF (15 tubes, 4.8%) versus without anti-VEGF (12 tubes, 2.6%) (P = 0.10). However, patients receiving anti-VEGF had on average a greater number of tube erosion events (2.1±0.7 events) compared with patients without anti-VEGF (1.3±0.7, P < 0.01). Ten patients (91%) received concurrent anti-VEGF injections at the time of tube erosion, and the average duration of prior anti-VEGF therapy was approximately 2 years. Tube erosion was noted 46.5±60.7 days from the preceding anti-VEGF injection. Secondary complications after tube revision in the anti-VEGF group included 5 explanted tubes for recurrent erosions.

CONCLUSIONS

Our results suggest intravitreal anti-VEGF injections are linked to higher rates of recurrent glaucoma tube erosions in patients with AMD. The majority of patients received chronic and serial anti-VEGF injections. Thus, additional consideration should be given to glaucoma surgical planning in patients receiving anti-VEGF injections, especially in those with a primary tube erosion.

Electron Beam Irradiated Corneal Versus Gamma-Irradiated Scleral Patch Graft Erosion Rates in Glaucoma Drainage Device Surgery

INTRODUCTION

Patch graft erosion and implant exposure is a known complication of glaucoma drainage device (GDD) surgery. Recently, electron beam (e-beam) irradiated corneal tissue ha s become available; however, limited data exist on the rates of erosion for e-beam irradiated corneal grafts compared to traditional scleral grafts after GDD surgery.

METHODS

This retrospective study examines the records of 253 eyes from 225 adult subjects who underwent GDD surgery with either e-beam irradiated corneal or scleral grafts at the Casey Eye Institute by five surgeons between April 22, 2014 and October 11, 2017. Surgical procedures and the occurrence of graft erosion were determined using billing codes and verified by manual review of electronic health records.

RESULTS

The average age at the time of surgery was 61.3 ± 17.5 years (n = 200) and 60.8 ± 16.8 years (n = 53) for the e-beam irradiated cornea and sclera groups, respectively. The average follow-up time post-surgery was 416 ± 345 days and 495 ± 343 days for the e-beam irradiated cornea and sclera groups, respectively. There were no statistically significant differences in sex, age, follow-up time, and glaucoma diagnosis between the groups; however, the e-beam irradiated cornea group was statistically more likely to have an Ahmed implant as compared to the sclera group. No erosion events were noted in either group.

CONCLUSION

e-Beam irradiated corneal grafts were used 3.8 times more frequently relative to scleral grafts, yet there were no cases of graft erosion in either group during the follow-up period.

Long-Term Functional Outcomes of Glaucoma Tube Shunt Revision Surgery

PURPOSE

To characterize long-term outcomes of tube shunt revision surgeries and identify factors associated with their failure.

DESIGN

Retrospective chart review.

PARTICIPANTS

One eye from each of 179 patients who underwent tube shunt revision surgery at the Wilmer Eye Institute between 2004 and 2015 with a minimum follow-up of 6 weeks.

METHODS

Eligible eyes were identified from billing records and data related to their care were extracted from electronic medical records. Eyes were analyzed in aggregate and by indication for revision, including hypotony, high intraocular pressure (IOP), tube reposition, and tube exposure.

MAIN OUTCOME MEASURES

Surgical failure, defined as a need for further tube shunt revision or other glaucoma surgery, unsatisfactory IOP at last follow-up, or both. Secondary outcomes included postoperative infection and functional visual impairment.

RESULTS

With a median follow-up of 4.2 years, 126 failures occurred among 179 eyes. By Kaplan-Meier analysis, the cumulative rates of surgical failure at 1, 2, and 5 years after revision were 49%, 59%, and 74%, respectively. Most revision failures (105/126) were the result of the need for additional surgery, whereas 11 eyes showed IOP above target levels and 10 eyes showed dysfunctionally low IOP at the last follow-up. Factors associated with failure in a stepwise regression model were revision for hypotony (hazard ratio [HR], 6.79; P = 0.002), different surgeons performing the original and revision surgeries (HR, 2.80; P = 0.002), longer duration of symptoms before revision (P = 0.01), revision of a right eye (HR, 1.92; P = 0.03), and presumed preoperative infection (HR, 2.47; P = 0.04). In univariate analysis, success varied significantly by prior surgeon (P = 0.01), but not by revision surgeon. There was a 16% cumulative incidence of postoperative infection, with the highest risk in those with presumed preoperative infections (P = 0.01) and in persons of non-African, non-European derivation (P = 0.03).

CONCLUSIONS

The estimated rate of failure of tube shunt revision is 75% by 5 years, most often because of a need for further surgery. The major potentially modifiable feature associated with success is tube shunt revision being performed by the original surgeon.

Repair of Exposed Ahmed Glaucoma Valve Tubes: Long-term Outcomes

PURPOSE

To assess the long-term outcomes of glaucoma drainage device (GDD) exposure repair with corneal lamellar patch graft covered by a buccal mucous membrane graft sutured to surrounding conjunctiva.

METHODS

In this retrospective longitudinal study, the charts of all patients who underwent buccal mucous membrane grafts combined with corneal lamellar patch grafts for exposed GDD tubes between the years 2006 to 2013 were reviewed. A minimum follow-up of 3 years was required for inclusion. Primary outcomes were categorized as complete success: adequate coverage throughout the study period without further intervention after 1 repair; qualified success: adequate coverage despite minor additional procedures (eg, suturing); failure: re-erosion of the GDD tube.

RESULTS

A total of 23 tube exposures were included. Average time from GDD insertion to first erosion was 54.0±38.9 months (range, 5 to 120). Complete success was achieved in 19 cases (82.6%), and qualified success in 1 case (4.3%). There were 3 failures (13.1%). Overall success (complete+qualified) after 1 or 2 buccal mucous membrane graft repairs was achieved in 22 of 23 cases (95.7%). Average follow-up time for the successful cases (complete+qualified) was 69.5±25.4 months (median, 72.5; range, 36 to 124). There was no difference in time to first erosion between the success (complete+qualified) and failure groups: 53.8±38.3 months (range, 5 to 120) and 62.3±51.6 months (range, 5 to 105), respectively (P=0.78).

CONCLUSIONS

Buccal mucous membrane grafts in combination with a lamellar corneal patch graft is a viable surgical strategy for eroded GDDs, providing good long-term outcomes; however, later interventions may be needed.