gms | German Medical Science

Purpose: To estimate the efficacy and costs of combined phacoemulsification and iStent inject trabecular bypass implant in mild-to-moderate open angle glaucoma in a real-world setting in Germany.

Methods: 96 eyes of 96 patients (49% male) were included in our interventional case series. Diagnoses included primary open angle glaucoma, pseudoexfoliative glaucoma and pigmentary glaucoma. Efficacy outcomes were intraocular pressure (IOP) and glaucoma medication reduction 4 weeks after surgery. To estimate costs, an individual patient sampling model was set up in Python 3.11 programming language to simulate patients in a Monte-Carlo approach over their lifetime. Age, mortality rate and medications were implemented at a cycle length of 0.33 years in a 2-state Markov model. Direct costs and cost savings due to discontinuation of glaucoma medication were recorded and compared to standard of care.

Results: Mean IOP was reduced from 18.7 (SD 4.2) mmHg to 14.6 (SD 3.0) mmHg. Topical glaucoma medications were reduced in 48 patients and completely discontinued in 33 patients. Mean medications were reduced from 2.23 (SD 1.12) to 1.42 (SD 1.34). Direct costs of the iStent inject procedure were € 1,288.81 including value-added tax. In our model, total direct costs accrued to € 4,265.47 for the iStent inject procedure vs. € 5,164.62 for standard of care over a patient’s lifetime. Sensitivity analysis showed the model’s robustness.

Conclusion: iStent inject combined with phacoemulsification reduces both IOP and glaucoma medication and profs to be an effective way of managing mild-to-moderate open angle glaucoma. Despite high initial costs, the procedure can lower treatment costs from a patient’s lifetime perspective.