Outcomes of Valved and Nonvalved Tube Shunts in Neovascular Glaucoma

Surgical outcomes including visual improvement after glaucoma surgery in patients with neovascular glaucoma

Purpose

This study aimed to evaluate the prognostic factors affecting surgical outcomes, including visual acuity (VA) improvement, after glaucoma surgery in patients with neovascular glaucoma (NVG).

Methods

The medical records of 116 patients (116 eyes) with NVG who had undergone trabeculectomy or Ahmed glaucoma valve implantation were reviewed retrospectively. The primary outcome measure was surgical success at 6 postoperative months, defined as sufficient intraocular pressure (IOP) reduction (IOP ≤21 mmHg, ≥20% reduction, regardless of topical medication use) without additional glaucoma surgery, hypotony, or progression to no light perception. Success was categorized as complete or qualified based on whether an improvement in VA was observed in addition to the abovementioned definition.

Results

The complete and qualified success rates at 6 months were 44.6% and 92.2%, respectively. Age (p = 0.001), preoperative best-corrected VA (p = 0.031), duration of decreased VA (p = 0.001), closed-angle status (p = 0.013), and etiology (p = 0.007) differed significantly between the groups with and without complete success. Multivariate analysis revealed that age (odds ratio [OR] 1.05; p = 0.026), duration of decreased VA (OR 1.05; p = 0.016), and 360° closed-angle status (OR 3.27; p = 0.031) were risk factors for surgical failure according to the complete success criteria, but not the qualified success criteria.

Conclusions

Patients with NVG showed improved visual prognosis and successful IOP reduction after glaucoma surgery at a relatively younger age if the duration of visual loss was not prolonged and the angle status was not completely closed.

RISK FACTORS FOR SURGERY OR BLINDNESS IN NEOVASCULAR GLAUCOMA EYES TREATED WITH ANTI-VEGF INJECTIONS BY A RETINA SPECIALIST

PURPOSE

To determine baseline patient characteristics that predict the need for glaucoma surgery or blindness in eyes with neovascular glaucoma (NVG) despite intravitreal antivascular endothelial growth factor therapy.

METHODS

This is a retrospective cohort study of patients with NVG who had not previously received glaucoma surgery and were treated with intravitreal antivascular endothelial growth factor injections at the time of diagnosis, from September 8, 2011, to May 8, 2020, at a large, retina subspecialty practice.

RESULTS

Of 301 newly presenting NVG eyes, 31% required glaucoma surgery and 20% progressed to no light perception vision despite treatment. Patients with intraocular pressure >35 mmHg ( P < 0.001), two or more topical glaucoma medications ( P = 0.003), worse than 20/100 vision ( P = 0.024), proliferative diabetic retinopathy ( P = 0.001), eye pain or discomfort ( P = 0.010), and new patient status ( P = 0.015) at the time of NVG diagnosis were at a higher risk of glaucoma surgery or blindness regardless of antivascular endothelial growth factor therapy. The effect of panretinal photocoagulation was not statistically significant in a subgroup analysis of patients without media opacity ( P = 0.199).

CONCLUSION

Several baseline characteristics at the time of presentation to a retina specialist with NVG seem to portend a higher risk of uncontrolled glaucoma despite the use of antivascular endothelial growth factor therapy. Prompt referral of these patients to a glaucoma specialist should be strongly considered.

Evaluation of the Hypertensive Phase after Ahmed Glaucoma Valve Implantation in Neovascular Glaucoma

Purpose

To compare Ahmed glaucoma valve (AGV) outcomes in neovascular glaucoma (NVG) eyes with and without a postoperative (PO) hypertensive (HTN) phase.

Design

Retrospective study at a single tertiary care center of patients who underwent AGV implantation for NVG treatment with ≥6-month follow-up.

Methods

Main outcome measures included intraocular pressure (IOP), number of glaucoma medications (GM), and failure at month 6 or at the most recent visit. Failure was defined as decline to no light perception (NLP) vision, IOP >21 mm Hg, or need for glaucoma reoperations (all with GM).

Results

A total of 76 eyes of 74 patients (37 without HTN phase and 39 with HTN phase) with a mean follow-up duration of 28.9 ± 25.7 months (p = 0.602) were included. Both groups had similar demographics, visual acuity (VA), number of GM, etiology of NVG, and retina treatment perioperatively. Baseline IOP was significantly higher in the HTN phase group (p = 0.001). Compared to eyes without an HTN phase, HTN phase eyes more commonly met failure criteria at month 6 (33.3 vs 9.1%; p = 0.01), but both groups had a comparable cumulative failure for the entire follow-up period (p = 0.180). At the most recent visit, the number of GM was higher in the HTN phase group (p = 0.019), but IOP was similar in both groups. PO complications were comparable and uncommon in both groups.

Conclusion

Hypertensive (HTN) phase following AGV implantation for NVG is associated with higher preoperative IOP and greater failure by PO month (POM) 6. However, eyes with and without the HTN phase had similar needs for GM and failure rates over the long term.

How to cite this article

Ramesh S, Shalaby WS, Myers JS, et al. Evaluation of the Hypertensive Phase after Ahmed Glaucoma Valve Implantation in Neovascular Glaucoma. J Curr Glaucoma Pract 2023;17(2):91-97.

Gonioscopy-assisted transluminal trabeculotomy in neovascular glaucoma: Salvaging the conventional outflow pathway

Purpose

To report a case of acute neovascular glaucoma with partial synechial angle closure secondary to central retinal vein occlusion that underwent gonioscopy-assisted transluminal trabeculotomy as well as near-monthly anti-vascular endothelial growth factor (VEGF) injections and panretinal photocoagulation (PRP) treatments.

Observations

Nine months after GATT, the patient had achieved intraocular pressure control on no medications. However, she was lost to follow up for 4 months and received no anti-VEGF or PRP during that time; she re-presented with acute NVG and complete synechial closure, and ultimately underwent aqueous shunt implantation.

Conclusions and Importance

To our knowledge, this is the first reported attempt of an ab interno angle surgery to successfully restore aqueous outflow through the conventional outflow pathway in an eye with acute NVG and partial synechial angle closure. We posit that this can be an effective approach to achieve IOP control in NVG with at least partially open angles, as long as sufficient anti-neovascular treatments are administered until the underlying neovascular drive achieves quiescence.

Outcomes of Ahmed glaucoma valve and transscleral cyclophotocoagulation in neovascular glaucoma

Purpose

To determine the outcomes of Ahmed glaucoma valve (AGV) and transscleral diode cyclophotocoagulation (CPC) in neovascular glaucoma (NVG).

Methods

This was a single-center retrospective comparative case series involving chart review of consecutive patients who underwent AGV or CPC for treatment of NVG and had ≥6 months of follow-up. Surgical failure at 6 months, defined as an IOP of >21 or <6 mm Hg with hypotony maculopathy after 1 month, progression to no light perception (NLP) vision, glaucoma reoperation, or removal of AGV were the main outcome measures.

Results

In total, 121 eyes of 121 patients were included (70 AGV and 51 CPC). Baseline demographics, visual acuity (VA), and intraocular pressure (IOP) were comparable between groups. At 6 months, failure was significantly higher in the CPC group than in the AGV group (43.1% vs. 17.1%, P = 0.020). Both groups had similar IOP and medication number at 6 months, but VA was significantly lower in the CPC group compared to the AGV group (2.4 ± 0.8 vs. 1.9 ± 1.0, P = 0.017). More CPC eyes required reoperation for glaucoma than AGV eyes (11.8% vs. 1.4%, P = 0.041). Multivariate regression analysis identified higher preoperative IOP (P = 0.001) and CPC surgery (P = 0.004) as independent predictors of surgical failure at 6 months. Age, sex, race, NVG etiology, bilaterality of the underlying retinal pathology, perioperative retina treatment, and prior or combined vitrectomy were not significant.

Conclusion

AGV and CPC had comparable IOP and medication reduction in NVG eyes at 6 months. CPC was more frequently associated with failure, reoperation for glaucoma, and worse visual outcomes. High preoperative IOP and CPC surgery independently predicted surgical failure.

The influence of etiology on surgical outcomes in neovascular glaucoma

Background

The authors sought to evaluate visual outcomes in patients with varying etiologies of neovascular glaucoma (NVG), who were treated with glaucoma drainage devices (GDD).

Methods

This was a retrospective case series of patients at a large academic teaching institution who had surgical intervention for neovascular glaucoma between September 2011 and May 2019. Eyes were included if there was documented neovascularization of the iris/angle with an intraocular pressure (IOP) > 21 mmHg at presentation. Eyes must also have been treated with surgical intervention that included a GDD. Primary outcome measure was visual acuity at the 1-year post-operative visit. Secondary outcome measure was qualified success after surgery defined by: pressure criteria (5 mmHg < IOP ≤ 21 mmHg), no re-operation for elevated IOP, and no loss of LP vision.

Results

One hundred twenty eyes met inclusion criteria. 61.7% had an etiology of proliferative diabetic retinopathy (PDR), 23.3% had retinal vein occlusions (RVO), and the remaining 15.0% suffered from other etiologies. Of patients treated with GDD, eyes with PDR had better vision compared to eyes with RVO at final evaluation (p = 0.041). There was a statistically significant difference (p = 0.027) in the mean number of glaucoma medications with Ahmed eyes (n = 70) requiring 1.9 medications and Baerveldt eyes (n = 46) requiring 1.3 medications at final evaluation.

Conclusions

In our study, many patients with NVG achieved meaningful vision, as defined by World Health Organization (WHO) guidelines, and IOP control after GDD. Outcomes differed between patients with PDR and RVO in favor of the PDR group. Different GDD devices had similar performance profiles for VA and IOP outcomes. Direct prospective comparison of Baerveldt, Ahmed, and cyclophotocoagulation represents the next phase of discovery.

Autologous Scleral Pocket Technique for Ahmed Glaucoma Valve Implantation with Pars Plana Tube Insertion for Neovascular Glaucoma

Specific postoperative complications, such as tube exposure and conjunctival erosion, have occurred despite the favorable surgical outcomes of tube shunt surgeries for refractory glaucoma. The new autologous scleral pocket technique is performed by inserting the tube into the vitreous cavity without using a donor scleral patch. The purpose of this study was to evaluate the surgical results of Ahmed glaucoma valve (AGV) implantation using this technique for neovascular glaucoma (NVG), which is one of the representative refractory types of glaucoma. This observational retrospective case series included 15 consecutive eyes of 15 patients with NVG who had undergone AGV implantation at Kobe University between January 2018 and December 2019. The mean preoperative intraocular pressure (IOP) was 37.2 ± 13.8 mmHg and the glaucoma drug score was 4.2 ± 2.2. The mean IOP and glaucoma drug score at 1 year postoperatively decreased to 15.0 ± 4.6 mmHg and 1.3 ± 2.0, respectively (p < 0.001). No significant change in the corneal endothelial cell density following surgery was observed (p = 0.09); however, one patient required an additional trabeculectomy at 7 months postoperatively. No cases of tube exposure or conjunctival erosion were observed at 1 year postoperatively. These results indicated the effectiveness and safety of this technique in patients with NVG.