Glaucoma Screening and OCT Imaging in Montréal
Glaucoma is a disease that slowly damages the optic nerve, the cable that carries what the eye sees to the brain. It usually causes no pain and no symptoms until a large part of the vision is already gone, and the vision it takes does not come back. The only way to find it early is a regular eye exam. At PrimeVision, our optometrists screen for glaucoma using eye pressure measurement, OCT imaging and visual field testing, all in the clinic.
Who is most at risk of glaucoma
- Adults over 40, with the risk rising every decade
- People with a parent, brother or sister who has glaucoma
- People with high eye pressure
- People who are very nearsighted
- People with diabetes
- People of African, Caribbean, Hispanic or Asian descent, depending on the type of glaucoma
- People who have used corticosteroids for a long time
How we screen for glaucoma
Eye pressure
We measure the pressure inside each eye. High pressure is the main risk factor for glaucoma, but it is not the whole story: some people develop glaucoma at normal pressure, and some people have high pressure without damage. That is why pressure alone is never enough.
Optic nerve examination
Your optometrist looks directly at the optic nerve at the back of the eye and notes its shape and colour, and compares it with previous visits.
OCT imaging
OCT, or optical coherence tomography, is a scan that uses light to measure the thickness of the nerve fibre layer around the optic nerve, in thousandths of a millimetre. It takes a few seconds, nothing touches the eye, and it can show thinning of the nerve before any vision is lost. OCT also images the macula, which helps detect macular degeneration and diabetic changes. Each scan is stored, so we can compare year over year and catch a slow change.
Visual field testing
A visual field test maps your side vision, where glaucoma does its first damage. You look at a central target and press a button each time you notice a small light. We use an Octopus 900 perimeter. The test takes a few minutes per eye and shows whether any area of your vision has become less sensitive.
What happens if something is found
Most people who are flagged at screening do not have glaucoma. They are what we call glaucoma suspects, and they are followed more closely, with repeat measurements, so that a real change is caught early. If the findings point to glaucoma, or if you need treatment that goes beyond what an optometrist provides, we refer you to an ophthalmologist and send the results of your tests with the referral. We continue to follow you alongside your specialist.
How often should I be screened?
Glaucoma screening is part of a complete eye exam. We recommend an eye exam every two years for adults, and every year from age 65 or if you have risk factors. If you are already followed for glaucoma or as a glaucoma suspect, your optometrist will set the schedule.
Is it covered?
RAMQ covers one complete eye exam a year for people 65 and over and for children under 18. Some additional tests, such as imaging, are not covered by RAMQ, and we will tell you the cost before doing one. Many private insurance plans cover eye exams and testing, and we bill most major insurers directly.
Book an eye exam
Book online or call 514-827-7463. PrimeVision is at 9520 Bd de l'Acadie, Suite 222, Montréal. See also: what every eye exam includes.