Influence of Vitrectomy-related Factors on the Outcome of Ahmed Glaucoma Valve Implantation

Systematic Literature Reviews Comparing the Long-Term Safety Outcomes for the Port Delivery System with Ranibizumab (PDS) Versus Other Ocular Implants

OBJECTIVES

To determine whether the types and rates of post-surgical complications associated with the Port Delivery System with ranibizumab (PDS) are comparable with those reported for other ocular implants that cross the sclera.

METHODS

Systematic literature reviews were conducted to determine the long-term (≥ 18-month) safety of ocular implants that cross the sclera in clinical trials and real-world studies. Complication types and rates were compared with those reported for the PDS in phase III clinical trials (Archway, Pagoda, and Pavilion).

RESULTS

Sixteen clinical trials (24 publications) and 43 real-world studies were identified reporting 30 complications in eyes with 15 implant types and 8 ocular diseases. Implants were associated with an acceptable, well-characterized safety profile, with most complications resolving spontaneously or with treatment. Device-related complications were reported in 0.7% (0.0-5.0%) of study eyes in clinical trials and 1.3% (0.0-14.5%) of eyes in real-world studies. Rates of conjunctival complications were 2.1% (0.0-22.8%) and 2.2% (0.9-4.6%), respectively. The overall types and rates of adverse events of special interest reported for the PDS in phase III trials (cataract, conjunctival bleb, vitreous hemorrhage, conjunctival erosion, conjunctival retraction, endophthalmitis, implant dislocation, retinal detachment, and hyphema) were within the ranges reported for other ocular implants.

CONCLUSIONS

The rates of complications reported in phase III clinical trials for the PDS were within the ranges reported for other ocular implants that cross the sclera. This suggests that the long-term safety of the PDS is consistent with other ocular devices established in ophthalmology clinical practice.

TRIAL REGISTRATION

PROSPERO international prospective register of systematic reviews: CRD5202234129, CRD42022343129.

Factors Affecting the Results of Ahmed Glaucoma Valve Implantation in Diabetic Neovascular Glaucoma With or Without Previous Pars Plana Vitrectomy

Objectives

The aim of this study was to compare the outcomes of Ahmed glaucoma valve implantation (AGVI) in neovascular glaucoma (NVG) due to proliferative diabetic retinopathy (PDR) with or without a pars plana vitrectomy (PPV) history and to analyze the factors affecting surgical failure.

Methods

Patients with NVG secondary to PDR undergoing AGVI at a single center were reviewed retrospectively. The surgical failure rates and post-operative complications were compared between eyes with (PPV-AGVI group) and without previous PPV (AGVI group). Failure was defined as loss of light perception or intraocular pressure (IOP) >17 mmHg despite maximum medication, or need of additional intervention for IOP control or for the management of complications. Survival analysis was investigated by Kaplan-Meier test. The possible factors for failure were analyzed with logistic regression analysis.

Results

The failure rates were 21.9% during the mean follow-up of 27.56±15.38 months and 14.3% during 23.63±12.38 months, in PPV-AGVI group (n=32) and in AGVI group (n=49), respectively (p=0.37). The frequency of complications and surgical intervention need for management of post-operative complications was similar between groups (p>0.05). There was no significant difference in survival analysis (p=0.13). The history of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection before AGVI was significantly associated with failure (odds ratio = 26.941, p=0.02).

Conclusion

The results of AGVI performed with long scleral tunnel technique were comparable in terms of failure rates, between NVG patients with and without previous diabetic vitrectomy. The only significant factor for failure was intravitreal anti-VEGF pre-treatment. This may be related to the necessity of anti-VEGF therapy in aggressive PDR, and also, anti-VEGF agents may increase fibrosis in the anterior chamber angle.

Eyewatch adjustable drainage device in vitrectomized eyes with refractory glaucoma

BACKGROUND

To describe the efficacy and safety of the adjustable system eyeWatch in vitrectomized glacomatous eyes.

METHODS

Prospective, non-comparative, small case series of 2 patients who underwent glaucoma drainage device implant with the eyeWatch system. Intraocular pressure, number of medications and early and late complications were evaluated.

RESULTS

None of the operated eyes developed early or late complications. After 1 week post operatively, the IOP raised at 28 mmHg in the first eye and 25 mmHg in the second one. The eyeWatch Pen was used to open and set the device into position 3 (that means implant half opened) After waiting for 30 min, IOP was 15 mmHg and 11 mmHg, respectively. Thirty days after surgery we set the EyeWatch into position 0 (that means implant full opened) even though the IOP was under control. A new IOP measurement was done and we registered that IOP was 14 mmHg and 10 mmHg respectively, and it remained stable after six months of follow up.

CONCLUSION

In conclusion, in our case series the use of eyeWatch adjustable system allows a safe and gradual regulation of the flow during post-operative management also in vitrectomized eyes. Considering the percentage of hypotony related complications in vitrectomized eyes this system is an effective and safe technique to handle glaucoma in post vitreoretinal surgery eyes.

Assessment of the Effectiveness of Glaucoma Treatment Using MicroPulse Transscleral Cyclophotocoagulation in Patients with Glaucoma Who Have Previously Undergone Vitreoretinal Surgery

INTRODUCTION

This retrospective study aimed to assess the effectiveness of using MicroPulse transscleral cyclophotocoagulation (µP-TSCPC) in patients who had previously undergone pars plana vitrectomy (PPV), depending on the endotamponade used.

METHODS

For the study, a total of 60 patients were enrolled who underwent PPV followed by tμP-TSCPC as a result of an increase in intraocular pressure (IOP) over the norm of 21 mmHg. In this group of patients, 20 received silicone oil endotamponade during PPV, 20 received sulfur hexafluoride gas SF6, and in another 20 a differentiated balanced salt solution (BSS) was used.

RESULTS

The main indications for conducting PPV were (1) retinal detachment (silicone oil endotamponade was used; n = 12); (2) dislocation/subluxation of the patient's own or artificial intraocular lens (balanced salt solution (BSS) endotamponade was used; n = 11); (3) the presence of an epiretinal membrane and/or a macular hole (BSS endotamponade was used; n = 9, or SF6; n = 20); and (4) hemorrhage into the vitreous chamber (silicone oil endotamponade was used; n = 8).

CONCLUSION

The choice of endotamponade used during PPV was not found to determine the effectiveness of µP-TSCPC treatment. The effectiveness of µP-TSCPC in patients after PPV depended, above all, on the etiology of the disease, for which PPV was previously performed. The lowest effectiveness of µP-TSCPC was noted in cases where the reason for conducting PPV was hemorrhage into the vitreous chamber and silicone oil endotamponade was used, while the highest effectiveness was noted in cases where PPV was conducted owing to the presence of an epiretinal membrane and/or a macular hole and SF6 endotamponade was used.

Two Year Randomized Prospective Comparison of Ahmed Valve Versus Baerveldt Implant in Vitrectomized Eyes

PRCIS

Ahmed Valve and Baerveldt shunt are efficacious options in vitrectomized eyes. Baerveldt implant achieves a lower mean intraocular pressure (IOP) at 2 years, with fewer medications and a higher percentage of medication-free patients.

PURPOSE

To investigate and compare the efficacy and complications between Ahmed FP7 Glaucoma Valve (AGV) and Baerveldt 101-350 Glaucoma Implant (BGI) in vitrectomized eyes.

MATERIALS AND METHODS

In this single-center randomized clinical trial, 43 vitrectomized eyes (39 patients) underwent glaucoma drainage device implantation. Eyes were randomized to receive either an AGV (FP7) or a BGI (101-350) and were followed for 2 years. Surgical success was defined as an IOP measurement≤18 mm Hg and≥5 mm Hg with or without glaucoma medication at 2 or more sequential visits after 3 months. The primary outcome was the comparison of the success rate at 2 years, while mean IOP, mean number of medications, and number of complications were considered secondary outcomes.

RESULTS

Kaplan-Meier estimates of the 2-year success rates in IOP control after GDD implantation were similar between the 2 groups; AGV group 81.8% (95% CI: 67.2%-99.6%) and BGI group 85.7% (95% CI: 72.0%-100.0%), (log-rank test P value = 0.74). Patients in the BGI group had a statistically significant lower mean IOP compared with the AGV group in all follow-up visits at 2, 6, 12, and 24 months (11.62 vs. 17.45 mm Hg at the latter P value <0.001). The BGI group required a significantly lower number of medications for IOP control at the 2-year visit compared with the AGV group (0.76±0.99 vs. 1.5±1.06 P value = 0.02) but had a higher number of complications (62% vs. 41%, respectively).

CONCLUSIONS

GDDs provide a viable solution for IOP control in vitrectomized eyes. Based on our prospective comparison, both Ahmed FP7 Glaucoma Valve and Baerveldt 101-350 Glaucoma Implant are efficacious options.

Ahmed glaucoma valve implantation for secondary glaucoma post-vitrectomy

BACKGROUND AND OBJECTIVE

Ahmed glaucoma valv (AGV) implantation is one of the successful surgical methods in secondary glaucoma that develops after pars plana vitrectomy (PPV). In our study, we aimed to evaluate the 1-year results of AGV implantation in patients with a history of PPV.

STUDY DESIGN

A total of 26 patients who underwent AGV implantation after PPV were included in our retrospective study. Fourteen of 26 patients had AGV implantation due to neovascular glaucoma (NVG) and 12 of them had secondary refractory galucoma. Data of these two groups of patients were evaluated in terms of IOP reduction, number of medication use, surgical complete and qualified success, surgical failure, and complications.

RESULTS

The mean IOP was 29.54 ± 4.87 mmHg at the preoperative of AGV implantation and 12.88 ± 4.17 at the twelfth month visit in overal group. There was no statistically significant difference between two groups in terms of IOP in preoperative and all postoperative visits (p > 0.05). The mean intervals between PPV and AGV implantation were 67 ± 34 days in NVG and 391 ± 500 days in non-NVG group (p = 0.017). In overall group, 91.7% of patients had improvement in BCVA at the twelfth month visit. Complete and qualified surgical success rates were 75%, 83.3% in NVG group and 50%, 91.7% in non-NVG group, respectively. There was no devastating complication in both groups.

CONCLUSION

AGV implantation is a safe and effective surgical method in uncontrolled IOP elevations after PPV. While surgical success and failure rates were similar between etiologies, the time required for AGV implantation after PPV was shorter in NVG etiology.

Ahmed glaucoma valve in vitrectomized eyes: An implantation technique to minimize early postoperative fluid-loss hypotony

PURPOSE

To describe the application of a modified Ahmed glaucoma valve (AGV) surgical implantation technique in vitrectomized eyes, in order to minimize the risk of early postoperative hypotony, which leads to hemorrhagic complications.

MATERIALS AND METHODS

Data of patients implanted with AGV using the surgical technique described were retrospectively reviewed. Inclusion criterion: glaucomatous eyes with previous history of pars plana vitrectomy. Intraocular pressure (IOP) measurement and ophthalmic examination were performed preoperatively and postoperatively weekly for 1 month for the detection of early hypotony, choroidal effusion/detachment, intraocular hemorrhage. The surgical technique consisted in creating a 5 mm long scleral tunnel with a 23 G needle reaching the anterior chamber at the iridocorneal angle, in which the Ahmed glaucoma valve tube was inserted.

RESULTS

Ten eyes of 10 patients were included. Median preoperative IOP was 30.5 mmHg [interquartile range (IQR) 28.3-33.0]; median postoperative IOP was 12.0 mmHg (IQR 9.3-13.0) at 1 week, and 12.5 mmHg (IQR 11.0-15.0) at 1 month. In no cases postoperative IOP was <8 mmHg. On the first postoperative day, five (50%) eyes showed few blood clots in the anterior chamber. On the second-week appointment, moderate choroidal effusion was observed in two eyes (20%). No hemorrhagic complications were observed.

CONCLUSIONS

The creation of a long intrascleral tunnel with a 23 G needle for AGV implantation in vitrectomized eyes could be effective in decreasing leakage through the space between the valve tube and the sclerocorneal tissue. This technique is safe, easy to perform, feasible and fast. Due to its advantages and good postoperative results, it could also be adopted in non-vitrectomized eyes.