Retinal-imaging breakthrough to swiftly detect eye diseases

Teaming up with photonics innovation hub, ACTPHAST 4R the scientists at Vrije Universiteit (VU) Amsterdam are progressing their scanner concept to a demonstrator stage to acquire data faster than existing optical imaging technologies.  

Some degenerative eye conditions like glaucoma, diabetic retinopathy, macular holes, and retinal diseases can progress to blindness if they are not diagnosed in their early stages due to missed opportunities from poor image quality or motion artefacts. 

Eye specialists currently use an imaging technique called Optical Coherence Tomography (OCT), a non-invasive test that uses light to build up an image of the retina by capturing cross-sectional ‘slices’.

However, because the eye is constantly moving, the images suffer from blurring and often only partial pictures are possible. OCT technology has never been fast enough to take a full image of a moving eye without blurring or expecting the patient to sit incredibly still.  

The lead researcher on this breakthrough development, Assistant Professor Imran Avci from the Department of Physics and Astronomy at VU Amsterdam, said: “Diagnoses of eye diseases that could lead to blindness require good quality images at an early stage.  

“Eye abnormalities can be so very subtle in the early phase that standard OCT can miss these tiny changes. Because our eyes are constantly moving to refresh the visual input, even at a microscopic level, it makes eye imaging very difficult without having blurred images.  

“Our scanner is different: with the data acquired fast enough, the overall goal is to have a real time imaging system. The rapid switch will enable us to perform real time high quality moving footage, or a ‘video’ of your eye.”

Light bundles

The scanner works by acquiring data from the light signal at rapid speeds by ‘bundling’ groups of information together. 

“Our new scanner will acquire the light signal data at least hundred times quicker than OCT systems that exist today.  

“Taking 100 to 120 reference points, our scanner 'bundles' them together, acquiring 20 arms at a time. However, it is our patented 'switch' that moves from bundle to bundle in nanoseconds that gives us the ability to quickly acquire the images in real time."

Standard OCT works by collecting data from a single sample arm, which is acquired mechanically using a scanner. The final image is formed by combining these individual images during post-processing.

“Processing each sample arm means existing technology is not fast enough to handle constant eye movement.  

“We can speed up the traditional OCT imaging system while keeping its sensitivity at a reasonable value. Our imaging speed improves while the signal to noise ratio is not sacrificed too much. The faster speed makes it possible to image dynamic situations or fast-moving parts of the body, like the eye.

“The OCT we have today uses a process called ‘eye-tracking’ which can be tricky and involves many elements to do it right. However, if we can manage to create an image before the eye moves (in 5-10 sec or so) then there is no need for tracking schemes,” said Dr Avci. 

ACTPHAST for Researchers

Working with ACTPHAST 4R - an EU innovation hub designed to give researchers working in academia throughout Europe access to top-level expertise and technologies in photonics to produce demonstrators for their scientific breakthroughs, similar to the supports provided by the separate ACTPHAST 4.0 innovation hub for European companies, especially for SMEs - Dr Avci’s team has been able to access the right technical and business coaching expertise to advance the scanner concept towards an actual product. 

ACTPHAST 4R Coordinator, Prof Hugo Thienpont of the Brussels Photonics Team (B-PHOT) at Vrije Universiteit Brussel (VUB) said: “Researchers like Dr Avci do not have easy access to the relevant cutting-edge photonics expertise and technologies within their own universities or even their own regions. 

“The ACTPHAST 4R support is crucial to bridging the gap between concept and demonstrator. Only an innovation hub like ACTPHAST 4R can provide the unique cross-border connections for bridging the innovation valley of death and accelerated TRL advancement.

“At this early stage for researchers, it means turning their scientific concepts into practical demonstrators which are cutting-edge and industrially relevant.  

If the demonstrator is successful, then they can look at commercialisation options such as licensing or a spin-out company from the university, and taking it to the next stage of a working prototype.”

Dr. Avci said: “ACTPHAST 4R has been essential in helping us develop our product because it has de-risked the investment we have to make. ACTPHAST 4R has given us access to the right know-how and equipment to overcome critical photonics challenges, including the invaluable opportunities for hands-on training at the facilities of the top competence centres in the key photonics technologies for our application. They make a huge difference to small research teams like ours.”

Specialising in the deployment of photonics technologies, ACTPHAST 4R gives researchers in academic institutes all over Europe the chance to turn their breakthrough scientific concepts into fully-functioning industrially-relevant demonstrators. 

“As a ‘one-stop-shop’ solution for researchers innovating in photonics, ACTPHAST 4R provided rapid access to the technical specialists and cutting-edge technologies in photonics that the team needed in order to further develop the product, and also substantially funded the innovation work. The application process via the ACTPHAST 4R website was quick and easy too.”

ACTPHAST 4R operates a continuous open call for researchers who wish to apply for innovation support. Applications can be made online via the ACTPHAST 4R website.