Your life and eyes 2 min read

What is an OCT scan?

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When you visit your optician, you may be forgiven in thinking that your appointment is simply just to test your eyesight. However, your local optician may also have access to equipment that can provide an in-depth picture of your overall eye health too, including screening for eye disease.

Modern eye care practices can now carry out a multitude of tests and checks to understand both your vision and the physical condition of your eyes, thanks to emerging technology becoming more available.

One such example of this is Optical Coherence Tomography (OCT). This is a hospital-quality scan that can be carried out in your local optician’s practice, using cutting-edge technology to look more closely at your retina.

Here we take a look at what happens in an OCT scan, and what benefits it could bring to your eye health.

What does an OCT scan do?

Many common eye diseases can creep up on you, without any significant symptoms. So, even if your vision and eyes appear perfectly fine, it’s useful for your optician to gain a full understanding of your overall eye health through additional tests.

In particular, an OCT scan can help to detect eye conditions like glaucoma, age-related macular degeneration and diabetic retinopathy. Your optician may recommend that you attend an OCT scan even when your eyes are healthy in order to provide a baseline image.

An OCT scan can help your optician to see what’s going on beneath the surface of your eye, providing a picture of the layers of your retina. Your optician can then map out the layers and measure the thickness. The optic nerve head is also visible at the back of your eye, so an OCT scan can also evaluate any disorders of the optic nerve.

Screenshot of an OCT scan demonstrating layers of the retina

How does an OCT scan work?

OCT technology uses light waves to take images of your retina; similar to how an ultrasound scan uses sound waves. During an OCT scan, you will be asked to sit in front of a small machine with your chin placed on a support. The instrument can scan your eye without touching it.

The scan is done on both eyes, one at a time. It is completely painless; you may be slightly dazzled by the flash of light that is given off in the machine, as if you have had your picture taken, but this will quickly disappear.

By attending multiple OCT scans over the years, your optician can notice subtle changes in the thickness of the layers. This can indicate early signs of eye conditions, making it much easier to diagnose, treat and manage.

How can I book an OCT scan?

OCT scans are generally recommended for those aged 25 or over, or if you are at heightened risk of developing eye conditions like glaucoma. Many independent opticians have access to optical coherence tomography technology.

You can book an OCT scan with your local optician by using our optician finder, and filtering for “advanced eye examination.”

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