Glaucoma: The Silent Thief of Vision — and Why Early Detection Is Everything

Glaucoma is the leading cause of irreversible blindness worldwide.¹ It is also, for most patients, entirely without symptoms until the damage is advanced. There is no pain. No sudden change in vision. Just a slow, progressive narrowing of the visual field that most people do not notice until a significant portion of their peripheral sight is already gone — permanently.

That is what makes consistent monitoring not just important, but genuinely urgent.

Your Annual Exam Is About More Than Your Prescription

Glasses and contacts are important — but they are only part of what we do at your annual wellness exam. Getting your prescription right improves your quality of life every day. Monitoring the health of your optic nerve and intraocular pressure protects your long-term vision in ways that no prescription change ever could.

Our primary goals during every wellness exam are to determine your most accurate prescription and to screen for early signs of glaucomatous damage. If findings warrant closer investigation, we schedule a dedicated follow-up medical exam for a more thorough, targeted evaluation — one that goes well beyond what a routine wellness visit is designed to capture.

What Glaucoma Actually Is

Glaucoma is not a single disease — it is a group of conditions characterized by progressive optic nerve damage, most commonly driven by elevated intraocular pressure (IOP). The optic nerve carries visual information from the eye to the brain; once its fibers are damaged, that loss is permanent.

Primary Open-Angle Glaucoma (POAG) is by far the most common form. The drainage angle of the eye remains open, but aqueous humor does not drain efficiently, causing IOP to rise gradually over time. It is asymptomatic until late-stage, which is what makes screening so critical.

Ocular Hypertension refers to elevated IOP without detectable optic nerve damage — a condition we monitor carefully, as it represents meaningful risk for conversion to POAG over time.

Narrow-Angle Glaucoma occurs when the drainage angle is anatomically narrow or closes, obstructing fluid outflow. This can present acutely with pain and vision changes, or chronically with few symptoms. Gonioscopy and imaging help us identify narrow angles before an acute event occurs. It is also worth noting that optic nerve damage can occur even when IOP falls within the statistically normal range — a reminder that pressure alone does not tell the full story, and that structural and functional testing are equally essential.

Risk Factors Worth Knowing

Elevated IOP is the most well-established modifiable risk factor, but it is not the only one. Family history of glaucoma significantly increases risk.² African ancestry is associated with higher prevalence, earlier onset, and more rapid progression of POAG — a disparity that is well-documented in the literature and worth discussing openly.³ Age, thin central corneal thickness, and high myopia are also meaningful contributors.

One risk factor that is frequently overlooked in routine care is corticosteroid use. Topical ophthalmic steroids are well known to elevate IOP in susceptible individuals, but systemic corticosteroids — including inhaled fluticasone and oral prednisone used for asthma, allergies, autoimmune conditions, and inflammatory diseases — can also raise IOP significantly in steroid responders.⁴ If you use corticosteroids in any form regularly, that history is important for us to know.

How We Evaluate for Glaucoma

Intraocular Pressure (IOP) is measured using both iCare rebound tonometry and Goldmann applanation tonometry. Both are used because each instrument has distinct strengths depending on corneal properties, and cross-referencing them produces a more reliable result.

Pachymetry measures central corneal thickness (CCT) — essential context for interpreting IOP accurately. Goldmann tonometry underestimates true IOP in thin corneas and overestimates it in thick ones. CCT is also an independent risk factor: the Ocular Hypertension Treatment Study found corneas at or below 555 microns carry a threefold greater risk of converting to POAG.⁵ Post-LASIK patients warrant particular attention here — LASIK permanently reduces corneal thickness, causing standard tonometry to chronically underestimate true IOP and potentially delay glaucoma diagnosis.⁶ Always disclose prior refractive surgery during your exam.

Optomap with OCT Mac Screening provides widefield retinal imaging with a baseline macular OCT screener, giving us a panoramic view of the optic nerve and nerve fiber layer as part of initial screening.

Zeiss OCT (Optic Nerve and RNFL Protocol) is the structural gold standard. High-resolution imaging of the retinal nerve fiber layer and optic nerve head detects thinning — often before visual field loss is measurable — and tracks progression with precision over time.

Visual Fields Testing maps functional peripheral vision. Structural OCT changes typically precede functional loss, which is why both are necessary — one without the other leaves meaningful gaps.

ERG (Electroretinography) measures the electrophysiological response of retinal ganglion cells — the cells most directly affected in glaucoma. It provides a functional signal independent of both structural imaging and subjective visual field testing, adding meaningful diagnostic depth in ambiguous or early-progression cases.⁷

Treatment and Co-Management

Glaucoma management is individualized. Topical IOP-lowering drops remain a well-established first-line option. Selective Laser Trabeculoplasty (SLT) is a minimally invasive laser procedure with strong evidence supporting its use as both a primary and adjunctive treatment.⁸ For patients requiring surgical intervention, we work with local surgeons who perform MIGS (Minimally Invasive Glaucoma Surgery) procedures. The appropriate path depends on your disease stage, risk profile, and treatment response — all of which are addressed at your dedicated medical follow-up visit.

The Bottom Line

Glaucoma is silent, progressive, and permanent — but manageable when caught early. If you have risk factors, a family history, or simply have not had a comprehensive exam recently, contact us to schedule your evaluation.

For educational purposes only. Not a substitute for individualized medical care.

Glaucoma

1. Tham YC, et al. Global prevalence of glaucoma and projections of glaucoma burden through 2040. Ophthalmology. 2014;121(11):2081–2090.

https://doi.org/10.1016/j.ophtha.2014.05.013

2. McMonnies CW. Glaucoma history and risk factors. J Optom. 2017;10(2):71–78. https://doi.org/10.1016/j.optom.2016.02.003

3. Racette L, et al. Primary open-angle glaucoma in blacks. Surv Ophthalmol. 2003;48(3):295–313.

https://doi.org/10.1016/S0039-6257(03)00028-6

4. Kersey JP, Broadway DC. Corticosteroid-induced glaucoma: a review of the literature. Eye. 2006;20(4):407–416.

https://doi.org/10.1038/sj.eye.6701895

5. Gordon MO, et al. The Ocular Hypertension Treatment Study: baseline factors that predict the onset of primary open-angle glaucoma. Arch

Ophthalmol. 2002;120(6):714–720. https://doi.org/10.1001/archopht.120.6.714

6. Recep OF, et al. Intraocular pressure after corneal refractive surgery. PubMed. 2018. https://pubmed.ncbi.nlm.nih.gov/30524165/

7. Banitt MR. The role of the ERG in glaucoma evaluation. J Glaucoma. 2013;22(Suppl 5):S45–S48.

https://doi.org/10.1097/IJG.0b013e3182934e4c

8. Gazzard G, et al. Selective laser trabeculoplasty versus eye drops for first-line treatment of ocular hypertension and glaucoma (LiGHT). Lancet. 2019;393(10180):1505–1516. https://doi.org/10.1016/S0140-6736(18)32213-X