Official ESCRS | European Society of Cataract & Refractive Surgeons


Cost-effectiveness analysis of iStent inject® implantation for the treatment of open-angle glaucoma in Spain

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Session Details

Session Title: Presented Poster Session: Combined Cataract Surgery & Cataract Surgery Complications

Venue: Poster Village: Pod 1

First Author: : J.Garcia-Feijoo SPAIN

Co Author(s): :    M. Teus   H. Falvey   S. Aceituno   M. Appierto              

Abstract Details


Cataract is a common comorbidity in patients with open angle glaucoma (OAG). In these subjects, the implantation of the micro invasive glaucoma surgery device iStent inject® and concomitant cataract surgery, has proved more effective in reducing intraocular pressure (IOP), as compared to cataract surgery alone. This study aimed to evaluate the cost-effectiveness of combined glaucoma-cataract surgery with iStent inject®, compared to cataract surgery alone, to achieve IOP control and medication use reduction in patients with mild-to-moderate OAG refractory under pharmacological treatment.


The analysis was carried out from the Spanish National Health System (NHS) perspective. Thus, only direct medical costs were considered.


A Markov model was developed to compare the lifetime clinical course of OAG patients undergoing either iStent Inject® combined surgery or cataract surgery alone. Efficacy (IOP and medication reduction) and resource use data were obtained from a clinical trial and published literature, respectively. Costs (€,2018) were extracted from national databases. Inputs were validated by experts. To estimate quality-adjusted life-years (QALYs), the impact of disease progression and treatment complications on health-related quality of life was considered. The incremental cost-utility ratio (ICUR) was then calculated as the additional cost per QALY gained. Probabilistic and deterministic sensitivity analyses were performed.


iStent Inject® combined surgery provided 12.48 QALYs/patient at a mean cost of €17,153.68. Cataract surgery alone was associated with lower QALYs (12.41) at a cost of €16,151.62, resulting in an ICUR of €13,077.45/QALY. Thus, iStent Inject® can be deemed cost-effective, compared to cataract surgery alone, both when considering a willingness-to-pay of €30,000/QALY (traditional), and when referring to the €21,000/QALY (recently suggested) threshold. At the indicated thresholds, the resulting probability of being cost-effective were 88.7% and 74.6%, respectively. The input with the highest impact on the ICUR was medication reduction (efficacy) for both procedures; nevertheless, iStent Inject remained cost-effective.


From the perspective of the Spanish NHS, the implantation of iStent inject®, as a combined procedure at the time of cataract surgery, would be an efficient alternative compared to cataract surgery alone, to achieve IOP control and medication use reduction, in patients with mild-to-moderate OAG.

Financial Disclosure:

... is employed by a for-profit company with an interest in the subject of the presentation, ... receives consulting fees, retainer, or contract payments from a competing company, ... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented

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