What is glaucoma?
Commonly known as the “silent thief of sight”, glaucoma is an eye condition that causes damage to the eye’s nerves due to increased pressure in the eye. This can often result in irreversible blindness unless addressed early on.
The condition is also the second-most-common cause of blindness worldwide. Despite that, it’s among the eye conditions least likely to be diagnosed. Estimates peg at least 50% of cases being undetected, with the figure rising to about 90% in some developing countries.
Glaucoma can occur in anyone at any age and often in people with a family history of it. Early diagnosis and careful management are the keys to preventing complete vision loss because, even if glaucoma itself isn’t treatable, blindness from it is avoidable.
What are the types and causes of glaucoma?
There are four major types of glaucoma:
- Primary Open-Angle Glaucoma
- Primary Angle-Closure Glaucoma
- Congenital Glaucoma
- Secondary Glaucoma
Primary Open-Angle Glaucoma
This is the most common type of glaucoma, caused by degeneration of the eye’s drainage system. Fluid in the eye can’t exit the eye fast enough and pressure in the eye builds up.
Over time, this high pressure damages the optic nerve at the back of the eye. Vision starts to fail, starting from the periphery. Total blindness occurs when the central vision also becomes affected in the advanced stage.
Primary Angle-Closure Glaucoma
This type of glaucoma occurs with a sudden blockage to the area where fluid usually exits the eye. This causes a quick, severe, and painful rise in eye pressure, usually with eye redness, blurring of vision, one-sided headache, nausea and vomiting.
The pain from this glaucoma is often mistaken for a migraine. This can lead people to dismiss it, which is dangerous because acute angle-closure glaucoma can cause blindness rapidly and is a medical emergency. Laser treatment may be indicated for this type of glaucoma.
This type of glaucoma is often hereditary and results from the abnormal development of the drainage system of the eye. As with the other types, early management is vital to preventing blindness. .
Secondary glaucomas arise as the effect of another condition. They can result from many causes, including trauma, mature cataracts, steroid medication, inflammatory eye disease, and diabetes.
Note that both open-angle and angle-closure sub-types are possible for this too, as with primary glaucoma.
Who is at risk for glaucoma?
There are risk factors that make you more likely to develop glaucoma. Here are the most noticeable:
- Age – The risk of developing glaucoma goes up as we age. Those aged 40 and above are most at risk of developing it.
- Asian ethnicity – Asians seem to have a higher risk of getting glaucoma (specifically angle-closure glaucoma) than most others.
- Chronic diseases – Due to the link between glaucoma and intraocular pressure (eye pressure), those with diseases like high blood pressure and diabetes are more likely to get the condition.
- Eye injuries – Trauma to the eye can lead to bleeding or injuries that block the eye’s drainage systems, elevating pressure.
- Genetics – A family history of glaucoma makes you more likely to develop it, and glaucoma genes have been identified as well.
- Ocular hypertension – This refers to high pressure within the eye, which typically means fluid in it can’t drain properly.
- Steroid use – Corticosteroids seem to increase the risk of developing the condition, usually secondary open-angle glaucoma.
- Refractive error – A correlation appears to exist between refractive errors like short-sightedness and long-sightedness, with the latter being associated with open-angle glaucoma and the latter with closed-angle glaucoma.
How is glaucoma diagnosed?
An eye doctor can diagnose glaucoma after performing a number of assessments and tests. Below are some of the possible examinations you may have to undergo to get glaucoma diagnosed.
Tonometry is a test where your intraocular pressure (the pressure in your eye) is measured. The normal range is 10 to 25 mmHg, although most eye doctors will recommend further testing for safety if you register at anything from 22 mmHg and above.
Dilated Eye Exam
In this test, special eye drops dilate or open your pupil so that the doctor can shine a light into your retina and inspect it as well as the optic nerve. This can help them discern if any damage has occurred to the optic nerve, which may be a sign of glaucoma.
Also called a gonioscopy, this test is focused on the angle where your iris and cornea meet. This is because this is where your eye’s drainage system is located. An eye doctor will use a special lens to inspect this area and see if the angle is open or closed (a sign of glaucoma).
Visual Field Test
This is a quick test to help the doctor figure out if you have lost vision from glaucoma already, as well as how severe the vision loss is.
How do you treat glaucoma?
Glaucoma is not curable. However, it is manageable
Successful glaucoma management depends on careful evaluation, early diagnosis, and prompt treatment. This means that the sooner one detects glaucoma, the higher the chances of preventing vision loss or blindness due to it.
Early diagnosis is made possible at our clinic as we have comprehensive and advanced glaucoma imaging technology, including the following:
- Confocal scanning laser ophthalmoscopy with topographical change analysis
- Optical coherence tomography
- Visual field perimetry with glaucoma progression analysis
The goal of treatment is to reduce the high eye pressure to a level that is safe for the optic nerve. Depending on the type and severity of glaucoma, this is achieved with medications, laser or eye surgery.
Our eye doctors are specialists with many years of experience treating glaucoma patients, so they can assess your situation to determine what may be best for your case.
Various types of eye medications are available to lower the eye pressure. Among other things, your doctor may prescribe ophthalmic eye drops for this.
Some types of glaucoma may be treated with lasers. Usually, they either open up some of the blocked drainage tubes in your eye or destroy some of the fluid-producing cells in your eye, with both resulting in lowered eye pressure. This procedure is painless and can be done very quickly as an outpatient procedure.
Those who are allergic to or not responsive to medications or laser procedures may need glaucoma surgery. This usually removes part of the drainage tubes for the eye, making drainage easier. After any treatment, regular follow-up is necessary to ensure that there is no progressive damage over time as one continues to age.
Glaucoma Screening and Treatment Fees
Glaucoma Eye Screening
- Visual acuity
- Subjective refraction
- Slit-lamp examination
- Retina & Optic disc evaluation
- Humphrey Visual Field Test
- Heifelberg Retinal Tomography Scan
- Optical Coherence Tomography Scan
- Corneal Pachymetry
Screening tests help detect eye diseases that you have not yet noticed. Early detection and timely treatment of these conditions can often prevent any permanent vision loss.
Fees indicated are updated as of January 2022 and prices are subject to GST.