Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Cataract surgery with and without trabecular micro-bypass stent in primary angle-closure glaucoma: a multi-centre cohort study

Eye volume 39, pages 2671–2677 (2025)Cite this article

Subjects

Abstract

Purpose

To compare the effectiveness and safety of phacoemulsification with iStents (phaco-iStent) vs. phacoemulsification alone (phaco-alone) in primary angle-closure glaucoma (PACG).

Methods

Retrospective, cohort, multi-centre study. The primary outcome was surgical success during follow-up, defining complete success(CS) as intraocular pressure(IOP) 6–18 mmHg without reoperations and ≥20% IOP reduction without medications, and qualified success(QS) as IOP 6–18 mmHg without reoperations and either ≥1medication reduction or ≥20% IOP reduction on the same medications. Secondary outcome measures were IOP reduction, number of glaucoma medications (nmeds), visual acuity (VA) and complications. Factors for failure were explored using Cox regression. Continuous variables were expressed as mean ± standard deviation.

Results

One hundred and eighty-five eyes included, 90 phaco-alone and 95 phaco-iStent (mean age 77.7 ± 9.0 years, mean follow-up 24.6 ± 9.2 months). Whereas no differences were found in IOP reduction between groups, nmeds reduction was higher in phaco-iStent at month 1 (p = 0.006), 6 (p = 0.002), 12 (p = 0.005) and 24 (p = 0.02). CS was achieved in 13.8% phaco-iStent and 10.1% phaco-alone (p = 0.46), while QS was achieved in 54.3% and 62.0%, respectively (p = 0.30), with no differences in the survival function distributions. Cystoid macular oedema and anterior uveitis were reported in six phaco-iStent. There were no long-term sight-threatening complications or differences in postoperative VA change between groups.

Conclusion

Adding iStent to phacoemulsification may provide a modest reduction in glaucoma medications with similar IOP control than phacoemulsification alone in selected PACG patients. While generally safe, the risks of postoperative macular oedema and uveitis should be weighed against the benefit of reducing medication. Prospective, cost-effectiveness studies of iStent in PACG are warranted.

Access through your institution
Buy or subscribe

This is a preview of subscription content, access via your institution

Access options

Access through your institution

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Kaplan–Meier survival analysis for qualified success (IOP 6–18 mmHg without reoperations and, either ≥1 medication reduction from baseline, or ≥20% IOP reduction on the same medications) and complete success (IOP 6–18 mmHg without reoperations and ≥20% IOP reduction from baseline off medications).
Fig. 2: Postoperative change in intraocular pressure (IOP) during follow-up.
Fig. 3: Percentages of eyes with reduced (light grey), same (dark grey) or increased (black) medications compared to baseline.

Similar content being viewed by others

Data availability

The datasets generated and/or analysed during the current study are available from the corresponding author on reasonable request. Supplementary Information is available at Eye’s website.

References

  1. Tham YC, Li X, Wong TY, Quigley HA, Aung T, Cheng CY. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systematic review and meta-analysis. Ophthalmology. 2014;121:2081–90.

    Article  PubMed  Google Scholar 

  2. Quigley HA, Broman AT. The number of people with glaucoma worldwide in 2010 and 2020. Br J Ophthalmol. 2006;90:262–7.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Weinreb RN, Aung T, Medeiros FA. The pathophysiology and treatment of glaucoma: a review. JAMA. 2014;311:1901–11.

    Article  PubMed  PubMed Central  Google Scholar 

  4. George R, Panda S & Vijaya L. Blindness in glaucoma: primary open-angle glaucoma versus primary angle-closure glaucoma—a meta-analysis. Eye. 2022;36:2099–105.

    Article  PubMed  Google Scholar 

  5. Quigley HA. Open-angle glaucoma. N Engl J Med. 1993;328:1097–106.

    Article  CAS  PubMed  Google Scholar 

  6. Pandav SS, Kaushik S, Jain R, Bansal R & Gupta A. Laser peripheral iridotomy across the spectrum of primary angle closure. Can J Ophthalmol. 2007;42:233–7.

    Article  PubMed  Google Scholar 

  7. Azuara-Blanco A, Burr J, Ramsay C, Cooper D, Foster PJ, Friedman DS, et al. Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial. Lancet. 2016;388:1389–97.

    Article  PubMed  Google Scholar 

  8. Liton PB, Gonzalez P. Stress response of the trabecular meshwork. J Glaucoma. 2008;17:378–85.

    Article  PubMed  PubMed Central  Google Scholar 

  9. Tham CCY, Kwong YYY, Leung DYL, Lam SW, Li FCH, Chiu TYH, et al. Phacoemulsification versus combined phacotrabeculectomy in medically uncontrolled chronic angle closure glaucoma with cataracts. Ophthalmology. 2009;116:725–31.e3.

    Article  PubMed  Google Scholar 

  10. Gedde SJ, Schiffman JC, Feuer WJ, Herndon LW, Brandt JD, Budenz DL, et al. Treatment outcomes in the Tube Versus Trabeculectomy (TVT) study after five years of follow-up. Am J Ophthalmol. 2012;153:789–803.e2.

    Article  PubMed  PubMed Central  Google Scholar 

  11. Jampel HD, Musch DC, Gillespie BW, Lichter PR, Wright MM, Guire KE, et al. Perioperative complications of trabeculectomy in the collaborative initial glaucoma treatment study (CIGTS). Am J Ophthalmol. 2005;140:16–22.

    Article  PubMed  Google Scholar 

  12. Rulli E, Biagioli E, Riva I, Gambirasio G, De Simone I, Floriani I, et al. Efficacy and safety of trabeculectomy vs nonpenetrating surgical procedures: a systematic review and meta-analysis. JAMA Ophthalmol. 2013;131:1573–82.

    Article  CAS  PubMed  Google Scholar 

  13. Gedde SJ. Results from the tube versus trabeculectomy study. Middle East Afr J Ophthalmol. 2009;16:107–11.

    Article  PubMed  PubMed Central  Google Scholar 

  14. Spiegel D, Wetzel W, Neuhann T, Stuermer J, Hoeh H, Garcia-Feijoo J, et al. Coexistent primary open-angle glaucoma and cataract: interim analysis of a trabecular micro-bypass stent and concurrent cataract surgery. Eur J Ophthalmol. 2009;19:393–9.

    Article  PubMed  Google Scholar 

  15. Fernández-Barrientos Y, García-Feijoó J, Martínez-de-la-Casa JM, Pablo LE, Fernández-Pérez C & García-Sánchez J. Fluorophotometric study of the effect of the glaukos trabecular microbypass stent on aqueous humor dynamics. Invest Ophthalmol Vis Sci. 2010;51:3327–32.

    Article  PubMed  Google Scholar 

  16. Salimi A, Watt H & Harasymowycz P. Long-term outcomes of two first-generation trabecular micro-bypass stents (iStent) with phacoemulsification in primary open-angle glaucoma: eight-year results. Eye Vis. 2021;8:43.

    Article  Google Scholar 

  17. Salimi A, Lapointe J, Harasymowycz P. One-year outcomes of second-generation trabecular micro-bypass stents (iStent Inject) implantation with cataract surgery in different glaucoma subtypes and severities. Ophthalmol Ther. 2019;8:563–75.

    Article  PubMed  PubMed Central  Google Scholar 

  18. Samuelson TW, Sarkisian SR, Lubeck DM, Stiles MC, Duh YJ, Romo EA, et al. Prospective, randomized, controlled pivotal trial of an Ab interno implanted trabecular micro-bypass in primary open-angle glaucoma and cataract: two-year results. Ophthalmology. 2019;126:811–21.

    Article  PubMed  Google Scholar 

  19. Guedes RAP, Gravina DM, Lake JC, Guedes VMP & Chaoubah A. One-year comparative evaluation of iStent or iStent inject implantation combined with cataract surgery in a single center. Adv Ther. 2019;36:2797–810.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Lindstrom R, Sarkisian SR, Lewis R, Hovanesian J, Voskanyan L. Four-year outcomes of two second-generation trabecular micro-bypass stents in patients with open-angle glaucoma on one medication. Clin Ophthalmol. 2020;14:71–80.

  21. Kahale F, Chanbour W, El Zein L, Brenner J, You JY & Melki S. Phacoemulsification with and without iStent: a systematic review and meta-analysis of comparative studies. Ophthalmic Res. 2023;66:1020–9.

    Article  PubMed  Google Scholar 

  22. Malvankar-Mehta MS, Iordanous Y, Chen YN, Wang WW, Patel SS, Costella J, et al. iStent with phacoemulsification versus phacoemulsification alone for patients with glaucoma and cataract: a meta-analysis. PLoS ONE. 2015;10:e0131770.

    Article  PubMed  PubMed Central  Google Scholar 

  23. Salimi A, Clement C, Shiu M & Harasymowycz P. Second-generation trabecular micro-bypass (iStent inject) with cataract surgery in eyes with normal-tension glaucoma: one-year outcomes of a multi-centre study. Ophthalmol Ther. 2020;9:585–96.

    Article  PubMed  PubMed Central  Google Scholar 

  24. Berdahl J, Voskanyan L, Myers JS, Katz LJ & Samuelson TW. iStent inject trabecular micro-bypass stents with topical prostaglandin as standalone treatment for open-angle glaucoma: 4-year outcomes. Clin Exp Ophthalmol. 2020;48:767–74.

    Article  PubMed  Google Scholar 

  25. Al Habash A & Khan O. Outcomes of combined iStent trabecular micro-bypass and cataract surgery for the treatment of open-angle glaucoma in a Saudi population. Clin Ophthalmol. 2020;14:1573–80.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Samuelson TW, Katz LJ, Wells JM, Duh YJ & Giamporcaro JE. US iStent Study Group. Randomized evaluation of the trabecular micro-bypass stent with phacoemulsification in patients with glaucoma and cataract. Ophthalmology. 2011;118:459–67.

    Article  PubMed  Google Scholar 

  27. Sarkisian SR, Grover DS, Gallardo MJ, Brubaker JW, Giamporcaro JE, Hornbeak DM, et al. Effectiveness and safety of iStent infinite trabecular micro-bypass for uncontrolled glaucoma. J Glaucoma. 2023;32:9–18.

    Article  PubMed  Google Scholar 

  28. Neuhann TH, Hornbeak DM, Neuhann R & Giamporcaro JE. Long-term effectiveness and safety of trabecular microbypass stent implantation with cataract surgery in patients with glaucoma or ocular hypertension: Five-year outcomes. J Cataract Refract Surg. 2019;45:312–20.

    Article  PubMed  Google Scholar 

  29. Salimi A, Watt H & Harasymowycz P. Three-year outcomes of second-generation trabecular micro-bypass stents (iStent inject) with phacoemulsification in various glaucoma subtypes and severities. J Glaucoma. 2021;30:266–75.

    Article  PubMed  Google Scholar 

  30. Hengerer FH, Auffarth GU, Conrad-Hengerer I. 7-year efficacy and safety of iStent inject trabecular micro-bypass in combined and standalone usage. Adv Ther. 2024;41:1481–95.

  31. Hengerer FH, Auffarth GU, Riffel C & Conrad-Hengerer I. Second-generation trabecular micro-bypass stents as standalone treatment for glaucoma: a 36-month prospective study. Adv Ther. 2019;36:1606–17.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Manning D. Real-world case series of iStent or iStent inject trabecular micro-bypass stents combined with cataract surgery. Ophthalmol Ther. 2019;8:549–61.

    Article  PubMed  PubMed Central  Google Scholar 

  33. Guedes RAP, Gravina DM, Lake JC, Guedes VMP, Chaoubah A. Intermediate results of iStent or iStent inject implantation combined with cataract surgery in a real-world setting: a longitudinal retrospective study. Ophthalmol Ther. 2019;8:87–100.

    Article  PubMed  PubMed Central  Google Scholar 

  34. Popovic M, Campos-Moller X, Saheb H & Ahmed IIK. Efficacy and adverse event profile of the iStent and iStent inject trabecular micro-bypass for open-angle glaucoma: a meta-analysis. J Curr Glaucoma Pr. 2018;12:67–84.

    Article  Google Scholar 

  35. Saheb H, Donnenfeld ED, Solomon KD, Voskanyan L, Chang DF, Samuelson TW, et al. Five-year outcomes prospective study of two first-generation trabecular micro-bypass stents (iStent®) in open-angle glaucoma. Curr Eye Res. 2021;46:224–31.

    Article  CAS  PubMed  Google Scholar 

  36. Fea AM, Cattel F, Gandolfi S, Buseghin G, Furneri G & Costagliola C. Cost-utility analysis of trabecular micro-bypass stents (TBS) in patients with mild-to-moderate open-angle Glaucoma in Italy. BMC Health Serv Res. 2021;21:824.

    Article  PubMed  PubMed Central  Google Scholar 

  37. Nieland K, Labbé A, Schweitzer C, Gicquel G, Kleintjens J, Ostawal A, et al. A cost-effectiveness analysis of iStent inject combined with phacoemulsification cataract surgery in patients with mild-to-moderate open-angle glaucoma in France. PLoS ONE. 2021;16:e0252130.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Salimi A, Abu-Nada M & Harasymowycz P. Matched cohort study of cataract surgery with and without trabecular microbypass stent implantation in primary angle-closure glaucoma. Am J Ophthalmol. 2021;224:310–20.

    Article  PubMed  Google Scholar 

  39. Chen DZ, Sng CCA, Sangtam T, Thomas A, Shen L, Huang PK, et al. Phacoemulsification vs phacoemulsification with micro-bypass stent implantation in primary angle closure and primary angle closure glaucoma: a randomized single-masked clinical study. Clin Exp Ophthalmol. 2020;48):450–61.

    Article  CAS  PubMed  Google Scholar 

  40. Hernstadt DJ, Cheng J, Htoon HM, Sangtam T, Thomas A & Sng CCA. Case series of combined iStent implantation and phacoemulsification in eyes with primary angle closure disease: one-year outcomes. Adv Ther. 2019;36:976–86.

    Article  CAS  PubMed  Google Scholar 

  41. Hamze H, Selvan H, Saravanan A, Pandey P, Masood I & Sung V. Phacoemulsification cataract surgery with and without iStent in primary angle closure glaucoma—a retrospective comparative study. Invest Ophthalmol Vis Sci. 2022:3687. https://iovs.arvojournals.org/article.aspx?articleid=2781495.

  42. Tan SZ & Au L. Manchester iStent study: 3-year results and cost analysis. Eye. 2016;30:1365–70.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Sood S, Heilenbach N, Sanchez V, Glied S, Chen S & Al-Aswad LA. Cost-effectiveness analysis of minimally invasive trabecular meshwork stents with phacoemulsification. Ophthalmol Glaucoma. 2022;5:284–96.

    Article  PubMed  Google Scholar 

  44. Teus MA, Belda JI, Lavín C, García-Feijoó J, Falvey H, Buseghin G, et al. Cost-effectiveness analysis of iStent Inject® implantation during cataract surgery compared to cataract surgery alone for mild to moderate open-angle glaucoma patients in Spain. Expert Rev Ophthalmol. 2021;16:319–28.

    Article  CAS  Google Scholar 

  45. NHS England NE. 2025/26 NHS Payment Scheme. 2024. https://www.england.nhs.uk/publication/2025-26-nhs-payment-scheme.

  46. Platt R, Reardon G & Mozaffari E. Observed time between prescription refills for newer ocular hypotensive agents: the effect of bottle size. Am J Ophthalmol. 2004;137:S17–23.

    Article  PubMed  Google Scholar 

Download references

Author information

Author notes

  1. These authors contributed equally: Sara Issa, Cristina Ginés-Gallego

Authors and Affiliations

  1. King’s College Hospital NHS Foundation Trust, London, UK

    Sara Issa, Cristina Ginés-Gallego, Ben Griffin, Madalina Pavel, Obeda Kailani, Mo Abu-Bakra, Sameer Trikha, Avi Kulkarni, Stafford Sansome & Gerassimos Lascaratos

  2. Al-Balqa Applied University, Al-Salt, Jordan

    Sara Issa

  3. Colchester Eye Centre of East Suffolk and North Essex NHS Foundation Trust, Colchester, UK

    Panagiotis Dervenis & Chrysostomos Dimitriou

  4. Section of Ophthalmology, School of Life Course Sciences, King’s College London, London, UK

    Gerassimos Lascaratos

Authors
  1. Sara Issa
    View author publications

    Search author on:PubMed Google Scholar

  2. Cristina Ginés-Gallego
    View author publications

    Search author on:PubMed Google Scholar

  3. Ben Griffin
    View author publications

    Search author on:PubMed Google Scholar

  4. Panagiotis Dervenis
    View author publications

    Search author on:PubMed Google Scholar

  5. Chrysostomos Dimitriou
    View author publications

    Search author on:PubMed Google Scholar

  6. Madalina Pavel
    View author publications

    Search author on:PubMed Google Scholar

  7. Obeda Kailani
    View author publications

    Search author on:PubMed Google Scholar

  8. Mo Abu-Bakra
    View author publications

    Search author on:PubMed Google Scholar

  9. Sameer Trikha
    View author publications

    Search author on:PubMed Google Scholar

  10. Avi Kulkarni
    View author publications

    Search author on:PubMed Google Scholar

  11. Stafford Sansome
    View author publications

    Search author on:PubMed Google Scholar

  12. Gerassimos Lascaratos
    View author publications

    Search author on:PubMed Google Scholar

Contributions

GL was responsible for the design, manuscript elaboration, literature review and global supervision of the study. CD contributed to the design of the study and provided feedback on the report. SI participated in the data collection, manuscript elaboration and literature review. CGG carried out the statistical analysis and contributed to the data collection and the manuscript elaboration. BG, PD, MP and SS participated in the data collection. OK, MAB, ST and AK contributed to the literature review and provided feedback on the report.

Corresponding author

Correspondence to Cristina Ginés-Gallego.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Issa, S., Ginés-Gallego, C., Griffin, B. et al. Cataract surgery with and without trabecular micro-bypass stent in primary angle-closure glaucoma: a multi-centre cohort study. Eye 39, 2671–2677 (2025). https://doi.org/10.1038/s41433-025-03923-x

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue date:

  • DOI: https://doi.org/10.1038/s41433-025-03923-x

Search

Advanced search

Quick links