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<\/p>\n<\/p>\n
LEARNING OBJECTIVES<\/p>\n
At the completion of this article, the reader should\u2026\u00a0Identify clinical signs of the interventional window in glaucoma, including ocular surface issues, IOP fluctuations, and steroid responses, to guide timely referral.
\nUnderstand the effects of chronic topical therapy on the ocular surface and how early MIGS can protect conjunctival health and future surgical outcomes.
\nApply evidence-based criteria for IOL selection in glaucoma, balancing contrast sensitivity, disease progression, and patient visual needs.<\/p>\n
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<\/p>\n
Dr Nikhil L. Kumar<\/p>\n
BMED GradDipMed(RefSurg) MPH FRANZCO FWCRS<\/p>\n
Medical Director and Principal Ophthalmic Surgeon<\/p>\n
Vision Clinic Sydney and Narellan Eye Specialists, NSW<\/p>\n
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<\/p>\n
Dr Ilesh Patel
MBBS MPH FRANZCO<\/p>\n
ophthalmologist
Hornsby Eye Specialists and Chatswood Eye Specialists<\/p>\n
Dr Nikhil L. Kumar and Dr Ilesh Patel outline practical strategies \u2013 from minimally invasive glaucoma surgery (MIGS) to laser trabeculoplasty \u2013 to protect the ocular surface, optimise IOP, and set patients up for sharper vision and more reliable cataract outcomes.<\/p>\n
Glaucoma management today looks markedly different from a decade ago. A move away from the traditional \u2018drops-first\u2019 approach towards a more proactive, interventional model is occurring. This paradigm shift is fundamentally changing what eye health professionals offer our patients.<\/p>\n
Central to this evolution is what we term \u2018interventional glaucoma\u2019 \u2013 the ability to achieve stable intraocular pressure (IOP) control while minimising the patient\u2019s daily treatment burden. <\/p>\n
Traditionally, elevated IOP meant reaching for the drop bottle. However, mounting evidence shows the significant hidden costs of the \u2018drop-first\u2019 approach.<\/p>\n
By recognising the interventional window earlier, optometrists can play a pivotal role in preserving the ocular surface, optimising refractive outcomes, and guiding patients toward long-term, sustainable glaucoma care.<\/p>\n
The true cost of topical therapy<\/p>\n
Chronic topical hypotensive therapy directly causes substantial ocular surface adverse effects. Current estimates suggest up to 60% of glaucoma patients develop concomitant ocular surface disease (OSD), with prevalence increasing in direct proportion to the number of medications prescribed.1 <\/p>\n
The primary culprit remains benzalkonium chloride (BAK), a quaternary ammonium compound that functions as a detergent, disrupting the tear film lipid layer and triggering evaporative dry eye. <\/p>\n
Beyond this mechanical effect, BAK induces a pro-inflammatory cascade, upregulating cytokines such as IL-6 and IL-8 while promoting infiltration of T-lymphocytes and macrophages into the conjunctiva.2 <\/p>\n
This chronic subclinical inflammation leads to goblet cell loss and squamous metaplasia of the ocular surface epithelium.<\/p>\n
Implications of OSD<\/p>\n
The consequences extend beyond patient comfort. There are direct implications for corneal and lenticular surgery, as well as future, more invasive glaucoma surgeries. <\/p>\n
OSD can adversely alter biometric accuracy for cataract surgery and also contribute to refractive inaccuracies post cataract surgery due to a chronically unstable tear film.<\/p>\n
A chronically inflamed conjunctiva predicts higher failure rates in future subconjunctival filtration surgeries due to enhanced fibrotic\u00a0responses.3 <\/p>\n
Long-term topical therapy-induced OSD is associated with increased conjunctival fibroblast activation, inflammatory cell infiltration, and extracellular matrix deposition, all of which compromise bleb formation and longevity. These pre-existing surface changes reduce the success of trabeculectomy and other subconjunctival procedures by accelerating post-operative scarring despite the use of antimetabolites.<\/p>\n
By shifting toward interventional glaucoma through technologies like selective laser trabeculoplasty and trabecular micro-bypass stents, we are not merely lowering pressure, we are reclaiming the ocular surface from chemical assault. <\/p>\n
Our goal is to break the \u2018preservative cycle\u2019 before irreversible damage occurs.4<\/p>\n
Balancing vsual expectations with progressive neuropathy<\/p>\n
Discussing the selection of appropriate intraocular lenses (IOL) for glaucoma patients requires careful navigation. <\/p>\n
When patients request complete \u2018spectacle-free\u2019 vision, trifocal IOLs frequently top their wish list. However, in glaucoma patients, these lenses are rarely, if ever, appropriate. The fundamental problem lies in how these lenses work: they split incoming light into multiple foci which reduces contrast sensitivity.<\/p>\n
This is critically important because glaucoma primarily erodes contrast sensitivity, often well before affecting Snellen acuity.5 <\/p>\n
So, layering a trifocal lens atop a compromised optic nerve will significantly degrade visual quality, particularly in low-light conditions.6 <\/p>\n
![\"\"](\"https:\/\/www.newsbeep.com\/au\/wp-content\/uploads\/2026\/04\/Screenshot-2026-04-17-at-3.24.20-pm.jpg\"\/)
Figures 1A and 1B. Ocular surface restoration following interventional glaucoma (iStent infinite).\u20281A (left): Pre-MIGS. Irregular tear film and epithelial compromise typical of the \u201cpreservative cycle.\u201d 1B (right): Post-MIGS (following medication reduction\/elimination). By transitioning from drop-dependent therapy to trabecular micro-bypass, the ocular surface environment has improved.<\/p>\n
Moreover, the unpredictable nature of glaucoma progression adds another layer of complexity. An IOL that performs adequately today may become a visual liability as the disease advances. <\/p>\n
If a patient develops an arcuate scotoma years after surgery, the split-light optics of a trifocal may exacerbate functional deficits, creating a \u2018double-jeopardy\u2019 of visual loss.7 <\/p>\n
The EDOF solution: Expanding the safe zone<\/p>\n
Patients with mild-to-moderate, stable glaucoma may be excellent candidates for extended depth of focus (EDOF) IOLs. These lenses provide a continuous range of vision with substantially lower impact on contrast sensitivity compared to diffractive\u00a0multifocals.8 <\/p>\n
Key advantages of EDOF lenses in glaucoma include:<\/p>\n
\u2022 Preserved contrast sensitivity: Multiple studies show EDOF lenses maintain contrast sensitivity closer to monofocal levels, unlike trifocals which show significant degradation9,10 <\/p>\n
\u2022 No impact on visual field testing: Unlike trifocal IOLs, EDOF lenses demonstrate no difference in visual field sensitivity on standard automated perimetry11\u00a0<\/p>\n
\u2022 Reduced dysphotopsias: Refractive EDOF designs like the Tecnis PureSee minimise glare and halos that can be particularly troublesome for glaucoma patients12\u00a0<\/p>\n
\u2022 Superior low-light performance: Especially important given that glaucoma patients already struggle with reduced\u00a0contrast<\/p>\n
Contemporary EDOF options<\/p>\n
The current Australian market offers several viable EDOF choices for glaucoma patients:<\/p>\n
Non-diffractive EDOF (Vivity-type): These use wavefront-shaping technology rather than diffractive rings, providing extended range while minimising photic phenomena. They excel for distance and intermediate vision, though near vision may require occasional reading glasses.13 <\/p>\n
Next-generation refractive EDOF (TECNIS PureSee): Designed to provide smooth extended vision with visual side effects comparable to monofocal IOLs. Recent comparative studies show superior intermediate and near vision versus enhanced monofocals while maintaining excellent distance vision.14\u00a0<\/p>\n
Enhanced monofocal IOLs (Eyhance, RayOne EMV): While not true EDOF lenses, these offer mild depth of focus extension with minimal compromise to visual quality, making them suitable for patients with moderate glaucoma or those particularly concerned about visual disturbances.15\u00a0<\/p>\n
Special considerations for pseudoexfoliation<\/p>\n
As discussed at AAO 2025, pseudoexfoliation patients require particularly individualised approaches.7\u00a0<\/p>\n
While advanced lenses can benefit these patients, considerations must include:<\/p>\n
\u2022 Capsular bag and zonular stability (critical for centration and toric correction)<\/p>\n
\u2022 Disease severity and progression risk<\/p>\n
\u2022 Pupil dynamics (essential for diffractive\u00a0optics)<\/p>\n
\u2022 Long-term visual function, not just short-term acuity<\/p>\n
![\"\"](\"https:\/\/www.newsbeep.com\/au\/wp-content\/uploads\/2026\/04\/Figure-2.-stents-implanted.jpg\"\/)
Figure 2. Three-point trabecular micro-bypass with iStent infinite. Image: Glaukos.<\/p>\n
The critical role of ocular surface health<\/p>\n
Success with any premium IOL \u2013 particularly EDOF technology \u2013 depends entirely on a pristine ocular surface. Accurate biometry and keratometry become impossible with BAK-induced keratopathy. Irregular astigmatism from a poor tear film can cause significant IOL power calculation errors.<\/p>\n
This is where preoperative early intervention such as selective laser trabeculoplasty or MIGS becomes transformative. <\/p>\n
By eliminating or reducing topical medications, we stabilise the tear film, ensure accurate IOL calculations, and ultimately deliver the refractive outcomes our patients expect. <\/p>\n
When cataract surgery is combined with procedures like iStent infinite, we can offer a \u2018refractive-plus\u2019 outcome: stabilising IOP, reducing medication burden, and providing high-quality functional vision.16 <\/p>\n
The power of multi-stent MIGS<\/p>\n
The traditional treatment pyramid has been flattened. We now view minimally invasive glaucoma surgery (MIGS) not as a last resort but as a foundational pillar of care. Among these technologies, trabecular micro-bypass systems have established new benchmarks for safety and efficacy.<\/p>\n
The three-stent advantage<\/p>\n
While early MIGS focused on single-point drainage, current evidence supports a more comprehensive approach to the trabecular meshwork. The iStent infinite system utilises three heparin-coated titanium stents placed across a wider arc of the canal (approximately 240\u00b0 or 8 clock hours), addressing the natural segmental flow of the eye\u2019s drainage system.17 <\/p>\n
Standalone versatility<\/p>\n
Perhaps the most significant shift for optometric practice is that MIGS is no longer strictly utilised solely in conjunction with cataract surgery. The iStent infinite system carries standalone indication in Australia, meaning we no longer must wait for cataract development before offering surgical solutions to patients struggling with IOP control or medication intolerance.<\/p>\n
This fundamentally changes our referral\u00a0paradigm. <\/p>\n
A 55-year-old professional with mild glaucoma, suffering from drop-induced OSD but still phakic, now has an interventional option that can eliminate medications while preserving their ocular surface for future refractive cataract surgery.<\/p>\n
Recognising the interventional window<\/p>\n
As primary providers, optometrists are well placed to identify the \u201cinterventional window\u201d \u2013 that critical moment when a patient\u2019s current therapy no longer serves their best\u00a0interests.<\/p>\n
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<\/p>\n
Clinical signals warranting referral<\/p>\n
\u2022 The \u201cfluctuator\u201d<\/p>\n
Patients with significant visit-to-visit IOP variations, often signalling poor adherence or \u201cwhite coat\u201d adherence. These patients may benefit more from 24\/7 mechanical pressure control than additional medications they do not use consistently.<\/p>\n
\u2022 Ocular surface distress<\/p>\n
Punctate keratitis, follicular conjunctivitis, or reduced tear break-up time suggests the \u201cdrop-induced\u201d pathology may be causing more harm than the glaucoma itself. Early intervention preserves the conjunctiva for both current quality of life and future glaucoma surgical success.<\/p>\n
\u2022 The refractive seeker<\/p>\n
Patients planning cataract surgery who desire EDOF outcomes require IOP stabilisation and ocular surface optimisation to ensure accurate biometry and long-term success. Addressing glaucoma before cataract surgery allows for proper surface healing and informed IOL selection.<\/p>\n
\u2022 The steroid responder<\/p>\n
Patients developing IOP spikes secondary to necessary steroid therapy (intravitreal injections, post-keratoplasty, inflammatory conditions) represent ideal candidates for trabecular bypass to re-establish physiologic\u00a0outflow.18 <\/p>\n
Case vignettes: Real-world applications<\/p>\n
Case 1: The refractive standalone success<\/p>\n
Patient: 55-year-old software architect with mild-to-moderate controlled open-angle\u00a0glaucoma.<\/p>\n
Presentation: Bilateral IOP 22 mmHg on latanoprost monotherapy. Complained of debilitating dry eye symptoms interfering with 10+ hour daily screen work. Desired premium refractive outcome for anticipated cataract surgery but currently phakic with minimal lens changes.<\/p>\n
Intervention: Bilateral staged standalone iStent infinite procedures.<\/p>\n
Outcome: Post-operatively achieved bilateral IOP of 15 mmHg on zero medications. Ocular surface recovered dramatically within 8 weeks, with TBUT improving from <5 seconds to 9 seconds. Stable biometry now established for future EDOF IOL planning when cataract progresses. Patient reports the procedure \u201cgave me my life back\u201d in terms of comfort and work productivity.<\/p>\n
Case 2: The steroid-induced spike<\/p>\n
Patient: 62-year-old with persistent diabetic macular oedema and moderate glaucoma on topical dual therapy.<\/p>\n
Presentation: Required regular intravitreal dexamethasone implants for vision-threatening macular oedema. Developed severe steroid-induced IOP spikes reaching 34 mmHg despite maximum tolerated medical therapy. Facing choice between vision loss from oedema or optic nerve damage from\u00a0pressure.<\/p>\n
Intervention: iStent infinite trabecular micro-bypass to re-establish physiologic outflow capacity.<\/p>\n
Outcome: IOP stabilised at 14-16 mmHg for 18+ months, allowing continued steroid treatment without optic nerve damage. Patient maintained visual acuity gains from oedema treatment without glaucoma\u00a0progression. <\/p>\n
Case 3: The surface-damaged multi-drop patient<\/p>\n
Patient: 68-year-old retired teacher with moderate POAG.<\/p>\n
Presentation: On three topical medications (latanoprost, dorzolamide\/timolol, brimonidine), IOP marginally controlled at 18-19 mmHg. Severe ocular surface disease with Grade 3 punctate keratitis, severe discomfort, and fluctuating vision affecting reading \u2013 her primary hobby.<\/p>\n
Intervention: Combined cataract surgery with iStent infinite, EDOF IOL.<\/p>\n
Outcome: Twelve months post-operatively: IOP 13 mmHg on zero medications, complete resolution of OSD, stable TBUT of 8 seconds, uncorrected distance vision 6\/6, requiring only +1.50 readers for sustained near work. Patient describes the outcome as \u201clife-changing \u2013 I can finally enjoy reading again without constant discomfort.\u201d<\/p>\n
Conclusion: Shaping the future of care<\/p>\n
The future of glaucoma management is micro-invasive, targeted, and genuinely patient-centric. <\/p>\n
As Australian ophthalmologists and optometrists, we serve as architects of our patients\u2019 visual journeys. By recognising both the limitations of medical therapy \u2013 particularly its impact on ocular surface health and future refractive choices \u2013 and embracing evidence-based interventional technologies, we can offer a meaningfully higher standard of care.<\/p>\n
The key is identifying that critical window when intervention serves the patient better than another prescription. For many of our patients, that window is far earlier than traditional paradigms suggested.\u00a0<\/p>\n
Dr Nikhil L. Kumar is a cataract, refractive and cornea subspecialist practicing at Vision Clinic Sydney and Narellan Eye Specialists. Dr Ilesh Patel is a cataract and glaucoma specialist at Hornsby Eye Specialists. Both authors are passionate about advancing patient-centred approaches to combined cataract and glaucoma management in\u00a0Australia.<\/p>\n
References:<\/p>\n
Micheletti JM, Shultz M, Singh IP, Samuelson TW. An emerging multi-mechanism and multi-modal approach in interventional glaucoma therapy. Ophthalmol Ther. 2024;13(1):13\u201322.
\nZhang X, Vadoothker S, Gottlieb JL, Liu Y. The impact of benzalkonium chloride on the ocular surface: a systematic review. J Ocul Pharmacol Ther. 2024;40(8):456\u201368.
\nBroadway DC, Grierson I, O\u2019Brien C, Hitchings RA. Adverse effects of topical antiglaucoma medication. II. The outcome of filtration surgery. Archives of Ophthalmology (Chicago, Ill. : 1960). 1994 Nov;112(11):1446-1454. DOI: 10.1001\/archopht.1994.01090230060021. PMID: 7980134.
\nGomes JAP, Azar DT, Baudouin C, et al. TFOS DEWS II iatrogenic report. Ocul Surf. 2024;22:511\u201338.
\nHong ASY, Ang BCH, Dorairaj E, Dorairaj S. Premium intraocular lenses in glaucoma: a systematic review. Bioengineering. 2023;10(9):993.
\nHarasymowycz P. Multifocal, EDOF, and light adjustable IOLs in glaucoma. AGS 2024 interview. American Academy of Ophthalmology Education. February 2025.
\nBerdahl J. Advanced IOL selection for pseudoexfoliation patients. Presentation at AAO 2025. Ophthalmology Times. February 2025.
\nPeterson CL, Wong TT, Perera S. Editorial: insights in glaucoma: 2023. Front Ophthalmol. 2025;4:1519088.
\nKohnen T, Suryakumar R. Extended depth-of-focus technology in intraocular lenses. J Cataract Refract Surg. 2020;46:298\u2013304.
\nLee S, Kim J, Park SH, et al. Comparative outcomes of the next-generation extended depth-of-focus intraocular lens and enhanced monofocal intraocular lens in cataract surgery. J Clin Med. 2025;14(14):4967.
\nTakahashi M, Yamashiro C, Yoshimoto T, et al. Influence of extended depth of focus intraocular lenses on visual field sensitivity. Sci Rep. 2024;14:8856.
\nAsena L, K\u0131rc\u0131 Dogan \u0130, Oto S, Dursun Alt\u0131nors D. Comparison of visual performance and quality of life with a new nondiffractive EDOF intraocular lens and a trifocal intraocular lens. J Cataract Refract Surg. 2024;50:847\u201354.
\nRocha KM. Extended depth of focus IOLs: the next chapter in refractive technology? J Refract Surg. 2017;33:146\u20139.
\nJohnson & Johnson Vision. Tecnis PureSee EDOF IOL clinical data. 2024\u20132025.
\nSharpe D. Comprehensive comparison of multifocal and EDOF IOLs available in the USA (2024\u20132026). Sharpe Vision Blog. March 2025.
\nSingh IP, Shultz M. Refractive outcomes in glaucoma: the role of EDOF and the danger of multifocality. J Cataract Refract Surg. 2025;51(4):442\u201350.
\nGlaukos Corporation. iStent infinite Trabecular Micro-Bypass System: Instructions for Use. 2024.
\nDonnenfeld ED, Solomon KD, Voskanyan L, et al. Third-generation trabecular micro-bypass implantation with phacoemulsification for glaucoma. Ophthalmol Ther. 2025;14:257\u201371.<\/p>\n","protected":false},"excerpt":{"rendered":"LEARNING OBJECTIVES At the completion of this article, the reader should\u2026\u00a0Identify clinical signs of the interventional window in…\n","protected":false},"author":2,"featured_media":346651,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[64,63,137],"class_list":{"0":"post-614144","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-au","9":"tag-australia","10":"tag-health"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/614144","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=614144"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/614144\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/346651"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=614144"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=614144"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=614144"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}