Phaco-plus’ procedures at forefront of modern glaucoma management

3 June 2026 | Ibtesham Hossain, Laura Crawley | EYE - Cornea, EYE - Cataract

Mechanisms and modalities: a brief practical overview

Phaco-plus refers to cataract extraction by phacoemulsification combined with an adjunctive IOP-lowering procedure performed through an ab interno or micro-incisional approach. In recent years, innovative technologies have revolutionised the surgical management of glaucoma, with iStent being the first ab interno MIGS device approved by the Food & Drug Administration (FDA) in 2012 [3].

Currently available MIGS devices include iStent inject, W & Infinite, OMNI, iTrack, Hydrus, GATT and KDB. Minimally invasive bleb forming surgery (MIBS) devices such as preser flow microshunt or xen gel stents are not typically included in the phaco-plus/MIGs group as they are, by definition, bleb forming and require postoperative management more in line with traditional trabeculectomy surgery.

Phaco-plus procedures generally aim to bypass or remove the main site of aqueous outflow resistance (trabecular meshwork), utilise the suprachoroidal space and/or dilate Schlemm’s canal/collector channels, such as:

Trabecular micro-bypass stents (e.g. iStent-type devices) and canal scaffolds (e.g. hydrus-type devices) to improve conventional outflow
Trabeculotomy/goniotomy (laser, device-assisted or blade-based) to incise/excise trabecular meshwork and open collector channels
Canaloplasty/viscodilation systems (ab interno) to dilate Schlemm’s canal and distal outflow
Suprachoroidal devices to exploit the alternative outflow pathway where potential pressure lowering is not limited by episcleral pressure.

Guideline-level messaging is consistent: MIGS tends to offer modest IOP reduction but can significantly reduce medication burden in mild disease, whereas bleb-forming procedures are generally needed when very low target pressures are required. Evidence is also emerging on the efficacy of phaco-plus techniques in moderate to advanced disease, enhancing our ability to offer truly personalised care to glaucoma patients [4].

Two for one: why the combination matters

A core mindset shift is to treat cataract surgery in glaucoma patients as an opportunity cost; if we do phaco alone today, we may miss the safest moment to add a low-risk outflow procedure. For example:

Phaco alone lowers IOP, but often modestly. Reviews and observational studies in primary open-angle glaucoma (POAG)/ocular hypertension (OHT) suggest average reductions that are typically small (often in the low single-digit mmHg range) and variable by baseline IOP and anatomy, with a wearing off of the IOP lowering effect at year 23.
Phaco-plus adds a consistent incremental benefit with cataract-like safety. National Institute for Clinical Excellence (NICE’s) interventional procedure guidance explicitly notes that trabecular bypass stent procedures are often combined with phacoemulsification [5].
Medication reduction is a meaningful endpoint. Drop intolerance, ocular surface disease, adherence fatigue, polypharmacy and the monitoring burden all matter to patients and services. In many combined-procedure trials, the most striking advantage over phaco alone is not a dramatic mean IOP difference, but a higher proportion of patients medication-free or on fewer agents, often for years [6]. This has wide ranging benefits, not only to an individual patient but for all patient cohorts in a healthcare system with rising demand and supply under significant pressure.
Nonadherence in glaucoma is reported as 30–80%, worsens over time and is associated with progressing disease [7]. Minimising dependency on a patient’s daily drop behaviour offers an opportunity for better long-term glaucoma control and preservation of visual field.

Taken together – in a patient who is already having phaco, and whose target IOP is compatible with trabecular/outflow-enhancing surgery – the marginal ‘ask’ is small (extra surgical minutes and a gonioscopic step), while the potential upside (fewer drops, fewer spikes, slower progression risk, delayed filtration, improved cost utility) is meaningful.

The evidence base: what should UK clinicians quote to patients?

While devices and techniques vary, the highest-impact trials share a common message: phaco-plus is primarily a ‘drop-reducing’ and moderately IOP-lowering strategy, with a strong safety profile compared with traditional filtering surgery. There is a growing body of evidence reflecting IOP lowering of 25–35% at 3–5 years for trabecular bypass devices with sustained cessation and reduction in topical medication and favourable safety profiles [4,6-10].

Safety signals: learning from previous devices

The MIGS story has also been shaped by vigilance. The voluntary recall of CyPass after longer-term follow-up signalled endothelial cell loss risk in some implantation scenarios, underscoring that ‘minimally invasive’ in the earliest devices did not mean ‘risk-free’, and that device design, long-term safety data and positioning matter [11].

Interestingly, the two-year data did not raise an issue [12] but the five-year data did [13,14]. This experience has strengthened governance expectations around training, audit and longer-term data capture. All new devices now require endothelial cell counts as part of clinical trials and licensing processes and devices currently in use have very favourable safety profiles increasing the confidence of the glaucoma surgeon community to widen the offer to patients.

Patient selection: when phaco-MIGS is the right operation

Phaco-plus is best framed as an option for patients who:

Have mild-to-moderate open-angle glaucoma (or similar open-angle phenotypes) with visually significant cataract and are due to have cataract surgery anyway
Have moderate to advanced disease, who would struggle with filtration or drainage device surgery, and where lifelong risk of glaucoma blindness is shortened
Need a target IOP that is achievable with modest surgical IOP lowering (often mid-teens rather than single digits)
Are controlled on 1–3 medications but want to reduce treatment burden, side-effects or adherence risk
Have an angle anatomy suitable for safe intraoperative gonioscopy and angle work.

Conversely, patients with advanced glaucoma, rapidly progressive field loss, or those needing very low target pressures should be counselled that MIGS may be insufficient – traditional filtration surgery may better match the risk-benefit profile, however it can act as a bridge to allow more time for individual patients to understand and prepare for filtration or glaucoma drainage device surgery. Similarly, iStent infinite, launched in the UK in the summer of 2025, offers three stents and may benefit patients with more advanced disease or those requiring a more dramatic drop in IOP whilst maintaining a more satisfactory risk-benefit profile [4].

Governance and the UK service context: the ‘where’ matters as much as the ‘what’

In England, cataract surgery is increasingly delivered at scale across multiple settings and glaucoma patients are frequently represented within these pathways. NICE interventional procedures guidance for trabecular stent bypass microsurgery highlights the importance of appropriate governance and audit arrangements [5].

More recently, UK glaucoma leaders have also raised concerns about case selection, informed consent and long-term follow-up when glaucoma patients undergo cataract surgery (with or without MIGS) in high-volume settings without integrated glaucoma expertise [10]. For phaco-plus to deliver its promise, it needs the same things glaucoma care always needs: correct diagnosis, reliable baseline staging and planned longitudinal monitoring with expert supervision.

Practical surgical considerations clinicians should not underplay

Phaco-plus is often described as ‘a cataract operation plus a few minutes’. That can be true operationally, but success depends on details:

Preoperative gonioscopy is non-negotiable; angle visibility, PAS, pigment and anatomy determine feasibility and likely efficacy.
IOP targets should be explicitly documented; MIGS is not a substitute for a filtering operation when a low target is required.
Postoperative IOP management should anticipate transient spikes or hyphaema, with clear rescue protocols to manage promptly. Arguably, glaucoma and cataract surgical teams are best placed to manage and supervise these cases.
Outcome tracking should include not just IOP, but medication count, visual field stability and corneal/endothelial health where relevant.
Skilled and experienced surgeons who are familiar with angle anatomy and surgery in a holistic way.

Looking ahead: phaco-plus as a platform, not a single procedure

The most exciting aspect of phaco-plus is that it functions as a platform strategy; cataract surgery becomes a predictable opportunity to optimise long-term glaucoma control. As laser-first pathways mature and sustained-release drug options (e.g. iDose® TR, Glaukos) expand, the future is likely to look less like a linear escalation and more like personalised layering – laser, selective pharmacology and a low-risk surgical adjunct at the cataract moment for the right patient.

For UK services facing rising glaucoma prevalence and persistent cataract throughput pressures, phaco-plus is not a ‘one size fits all’ answer – used thoughtfully, it is increasingly central to how modern glaucoma management balances efficacy, safety and lifetime treatment burden.

References

1. Meliante LA, Stuart KV, Luben RN, et al. Current burden and future projections of glaucoma in the United Kingdom. Br J Ophthalmol 2026:bjo-2025-328373 [ePub ahead of print].
2. www.rcophth.ac.uk/news-views/
latest-audit-figures-show-improved
-outcomes-of-cataract-procedures
3. www.accessdata.fda.gov/scripts/cdrh/
cfdocs/cfpma/pma.cfm?id=P080030
4. Sarkisian SR Jr, Grover DS, Gallardo MJ, et al. Effectiveness and safety of iStent Infinite trabecular micro-bypass for uncontrolled glaucoma. J Glaucoma 2023;32(1):9–18.
5. www.nice.org.uk/guidance/ipg575
6. Samuelson TW, Sarkisian SR Jr, Lubeck DM, 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(6):811–21.
7. Radcliffe NM, Shah M, Samuelson TW. Challenging the “topical medications-first” approach to glaucoma: a treatment paradigm in evolution. Ophthalmol Ther 2023;12(6):2823–39.
8. Ahmed IIK, De Francesco T, Rhee D, et al. Long-term outcomes from the HORIZON randomized trial for a Schlemm’s canal microstent in combination cataract and glaucoma surgery. Ophthalmology 2022;129(7):742–51.
9. Fan Gaskin JC, Bigirimana D, Kong GYX, et al. Prospective, randomized controlled trial of cataract surgery vs combined cataract surgery with insertion of iStent inject. Ophthalmol Glaucoma 2024;7(4):326–34.
10. Ansari AS, Tatham AJ, Amerasinghe N, Gazzard G. Building consensus on MIGS: insights from a UKEGS survey. Eye (Lond) 2025;39(11):2107–9.
11. Kamthan G. The suprachoroidal space reloaded. Glaucoma Physician (2023) [Online]:
https://glaucomaphysician.net/issues/2023/
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12. Vold S, Ahmed II, Craven ER, et al. Two-year COMPASS trial results: supraciliary microstenting with phacoemulsification in patients with open-angle glaucoma and cataracts. Ophthalmology 2016;123(10):2103–12.
13. Reiss G, Clifford B, Vold S, et al. Safety and effectiveness of CyPass Supraciliary Micro-Stent in primary open-angle glaucoma: 5-year results from the COMPASS XT study. Am J Ophthalmol 2019;208:219–25.
14. Lass JH, Benetz BA, He J, et al. Corneal endothelial cell loss and morphometric changes 5 years after phacoemulsification with or without CyPass Micro-Stent. Am J Ophthalmol 2019;208:211–8.

[All links last accessed April 2026]

Declaration of competing interests: Laura Crawley has had educational grants from Glaukos, Scope, Thea and Santen for providing educational content and advisory board contributions.