Glaucoma steals sight from the outside in, painlessly, and by the time you notice it roughly forty per cent of your optic nerve fibres are already gone. Early detection with OCT-RNFL and perimetry, then drops, SLT laser or surgery to hold the line for the rest of your life.
Glaucoma is a group of diseases in which the optic nerve — the cable of roughly a million fibres carrying visual information from your eye to your brain — is progressively damaged. In most cases the driver is intraocular pressure that is too high for that particular nerve to tolerate. Fluid is produced continuously inside the eye and drains through a meshwork near the angle between iris and cornea; when drainage falls behind production, pressure rises.
The cruelty of the disease lies in the order in which it takes vision. Damage begins in the peripheral field, and the brain fills in the missing regions so convincingly that patients notice nothing. Central vision, the part you read the eye chart with, is preserved until late. It is entirely typical for someone to have 6/6 vision on the chart and have lost half their visual field.
That damage is permanent. Nerve fibres, once lost, do not regenerate, and no treatment available today restores field that has already gone. Everything in glaucoma management is aimed at protecting what remains — which means the value of a diagnosis is directly proportional to how early it is made.
India carries an enormous undiagnosed glaucoma burden, and a large proportion of cases are found incidentally during a routine check-up or a cataract assessment. If you are over forty, or have a parent or sibling with glaucoma, a baseline screening is one of the highest-value tests in ophthalmology.
Chronic open-angle glaucoma usually has no symptoms at all until advanced. Acute angle-closure glaucoma, by contrast, is a dramatic emergency. Know both:
The commonest type. The drainage angle looks anatomically open but functions poorly, so pressure creeps up over years with no symptoms whatsoever. Detected only through pressure measurement, optic disc examination, OCT-RNFL and visual field testing.
The iris crowds the drainage angle. May be chronic and silent, or present as an acute attack with severe pain, redness, a rock-hard eye, vomiting and rapid vision loss — a true emergency requiring immediate pressure reduction and laser iridotomy. Commoner in hypermetropic eyes and in women.
Classic optic nerve damage and visual field loss despite pressure readings within the statistically normal range. Often related to poor blood flow to the nerve. Easily missed if screening relies on pressure alone, which is why disc examination and OCT matter so much.
Pressure rise caused by something else — steroid use, uveitis, trauma, advanced diabetic eye disease with new vessels on the iris, pseudoexfoliation, or a swollen cataract. Treating the underlying cause is as important as lowering the pressure.
In infants and young children, presenting with watering, light sensitivity, enlarged cloudy corneas and constant eye rubbing. Requires urgent surgical management to protect a visual system still under development.
Raised pressure with a healthy nerve, or a suspicious-looking disc with normal pressure. Not everyone needs treating — but everyone in this group needs a documented baseline and structured monitoring so that any conversion is caught early.
No single test diagnoses glaucoma. The diagnosis is built from pressure, nerve structure and nerve function together, and then tracked over years to see whether it is progressing.
Goldmann applanation tonometry, the reference standard. Corneal thickness is measured too, since a thick cornea overestimates pressure and a thin one underestimates it — and thin corneas are themselves an independent risk factor.
The optic nerve head is examined for cupping, rim thinning, notching and disc haemorrhages, and photographed so that changes years apart can be compared objectively rather than from memory.
A mirrored lens on the eye surface lets the drainage angle itself be visualised. This distinguishes open-angle from angle-closure glaucoma, which matters because the treatments differ completely.
Measures the thickness of the retinal nerve fibre layer in microns. It can detect structural loss several years before it shows on a visual field test, making it the most valuable early-detection tool available.
Visual field testing maps how much functional vision has been lost and where. Repeated at intervals, it is the definitive way of determining whether the disease is stable or progressing on the current treatment.
Prostaglandin analogues, beta blockers, alpha agonists and carbonic anhydrase inhibitors, alone or combined, to lower pressure to an individually set target. Drops work only if used every day for life — adherence is the commonest reason treatment fails.
Selective laser applied to the drainage meshwork to improve outflow. Painless, takes minutes in the outpatient clinic, and is increasingly offered as first-line treatment instead of drops. The effect may wane after some years and can be repeated.
When drops and laser cannot hold the target pressure, a surgical drainage channel is created, a glaucoma drainage device is implanted, or a minimally invasive procedure is combined with cataract surgery. Surgery lowers pressure; it does not restore lost vision.
Pressure checks, repeat OCT and repeat fields at defined intervals, indefinitely. Glaucoma is managed the way hypertension is managed — controlled, not cured.
A glaucoma diagnosis is not a sentence to blindness. The great majority of patients who are diagnosed reasonably early and who take their treatment consistently keep useful vision for the rest of their lives. The ones who lose sight are almost always those who stopped their drops because their eyes felt fine, or who stopped attending reviews.
Because the disease is silent, you will never feel your treatment working. That is precisely why the follow-up schedule exists — the scans and fields are how you and your doctor find out whether it is.
Glaucoma is a long-term condition, so the meaningful cost is annual rather than one-off. Indicative ranges in Delhi NCR:
Indicative ranges for Delhi NCR as a guide only. Your written estimate is given after examination and depends on the technology, lens or drug used, hospital tariff and insurance cover. Most procedures are supported by cashless insurance at Max hospitals.
Retina, cataract, glaucoma and LASIK evaluations at Max Smart Saket, Max Panchsheel Park and Synergy Eye Care.
