by Graham Strong - November 10, 2018
Eye patients at the Lions Vision Care Centre in the Thunder Bay Regional Health Sciences Centre may soon receive faster, non-invasive eye testing that will improve diagnosis of some of the most common vision problems. Optical coherence tomography angiography (OCTA) is a new technology that is a huge leap forward from fluorescein angiography. Not only does OCTA provide clearer images, it doesn’t require an injection of dye in the arm.
Eliminating that dye, which can have unpleasant side effects including in rare cases a serious reaction called anaphylaxis, is a huge advantage in itself.
“OCTA is a non-invasive technique that allows you to visualize the retina layers and the optic nerve,” said Dr. Leland Dhurjon, an ophthalmologist at the Lions Vision Care Centre. “We will use this to test for glaucoma, macular degeneration, and diabetes-related vision problems though we will use it for some of the rarer conditions as well.”
Blood vessels in the eye become much clearer and more detailed with the new OCTA imaging technology (right). These images are near scale; notice the loop at the top right of each image. OCTA is also faster and non-invasive – no dye injection required.
So what exactly does OCTA do? Imagine you’re looking at a picture of a tree that was taken from far away and that’s out of focus. The image will be blurry, and you won’t always be able to tell the branches apart from each other. Now imagine looking at the same tree from closer up and in focus. You’ll be able to see each branch, twig, and even each leaf in great detail.
This isn’t exactly how the OCTA technology works, but the tree example gives you a good idea of the results (see the picture above). OCTA takes images in layers to provide sharper, more detailed images – obviously that’s extremely important when it comes to eye health. The system can also take all the layers and create a 3D image of the eye rather than just a flat, X-ray-like image so that doctors can look at problem areas from different angles.
The OCTA technology provides other advantages as well.
“The more exciting thing is that it can actually measure blood flow within the eye – what we call flow analysis. This gives us even more information about what’s happening in the eye and allows us to create more effective treatment plans,” Dr. Dhurjon said.
And it’s fast. Dr. Dhurjon said that patients will only have to wait in the chin strap for about five minutes during the eye exam, compared to 20 minutes with the current method. The actual imaging takes about one second each from two different directions.
As much as this technology is a leap forward, it won’t completely replace the injection-based fluorescein angiography. “More and more, it’s been found to be a valuable adjunctive test (used together with OCTA) for conditions such as diabetes and macular degeneration in some cases.” However, for the majority of eye patients, OCTA will be a welcome relief.
We Need Your Help!
The OCTA technology, like most new equipment, is quite expensive – we can’t purchase it without your donation! As past donors supporting the Lions Vision Care Centre know, even a small contribution from you can help bring this amazing new technology to Thunder Bay to benefit eye patients. If you or a loved one has ever come for an eye exam, you know how important faster, injection-free tests can be. Please call the Thunder Bay Regional Health Sciences Foundation right now at (807) 345-4673 to make your donation, visit our website at healthsciencesfoundation.ca to donate online, or drop by the Donation Centre at the Health Sciences Centre (next to Robin’s Donuts).
Take another look at the picture above to see the difference your donation today will make!