Quantum Imaging Diagnostic Tool for Early Detection of Macular Degeneration
1. What is the aim of your research project?
The aim of the research project is to develop a new diagnostic tool, the Structured Light Imaging Device, that utilizes quantum technologies to detect the early-stage of the age-related macular degeneration (AMD). The device enables early preventive treatment of AMD before irreversible vision loss occurs. The ultimate goal of the project is to reduce the burden of age-related vision loss.
2. Could you please tell us more about the background of your research programme?
AMD is a condition that causes a loss of central vision and has a significant impact on quality of life. While current treatments can slow the progression of the disease, they cannot restore lost vision. Unfortunately, macular degeneration is often diagnosed after vision loss has already occurred, making early detection crucial.
That's why the Centre for Eye and Vision Research (CEVR) is working to develop technologies that can prevent vision loss. To achieve this goal, CEVR has teamed up with the Institute for Quantum Computing (IQC) at the University of Waterloo to create a new diagnostic tool that utilizes quantum imaging technologies to detect early-stage macular degeneration. The device, known as the Structured Light Imaging Microscope (SLIM), measures the interaction between structured light beams and the eye. Structured light can be seen by individuals with healthy eyes in the form of a pattern in their field of vision, but this is compromised in people with macular degeneration due to damage to the macula, the part of the retina responsible for central vision.
3. Could you please share ground-breaking experimental / any methods that you are using in your research?
The ability of polarization perception by the human eye has been known for decades. However, the entoptic phenomena caused by the interaction between polarized light and the retina (particularly the macula pigment in the central retinal region), known as the Haidinger’s brush, is very difficult to see even for people with healthy vision. It is a small bowtie-like shadow which only lasts a couple of seconds before it vanishes.
Using our novel device, we are able to expand this entoptic phenomenon into a larger, more visible pattern. We can manipulate the structured light source such that the pattern appears to have many more fringes. With all of these enhancements, the pattern becomes easily perceivable by healthy eyes and therefore, we are able to quantify the ability to see such a pattern. Since the ability to perceive polarized light is related to the health of the macula, any sign of deterioration in polarization perception ability may indicate early signs of AMD.
4. What are the challenges in your research?
One of the main challenges is recruitment of early AMD patients for our resach studies. Our device aims to screen for the early stages of AMD and therefore requires continuous testing and validation on participants with healthy eyes and with different stages of AMD. However, since there is no currently available device that can effectively screen for early AMD, it makes it difficult to find and recruit early AMD for our experimental studies.
Fortunately, with the aid of the various clinical and hospital connections of CEVR and the two host universities (The Hong Kong Polytechnic University and University of Waterloo), we are able to connect with a large group of patients with various stages of AMD. Also, AMD eventually affects both eyes although it can develop earlier in one eye compared to the other. This means that we can recruit people with later stages of AMD in one eye while the other eye is at a much earlier stage.
5. Can you share any current data or major findings?
Our initial findings show that people with healthy eyes have no difficulty in seeing the entoptic pattern generated by our polarization-varying structured light device. On the other hand, people with signs of AMD have difficulty perceiving this entoptic pattern. Even subjects with nearly perfect visual acuity and contrast sensitivity but with signs of AMD have difficulty in performing our perception task.
6. How is your research program unique?
Our device is the world’s first adoption of Quantum Optics into Vision Sciences. Multidisciplinary specialists within our team are identifying new applications for the SLIM in optometry and ophthalmology.
7. How is your research contributing to improving vision/ocular health as well as changing lives for the better?
Successful commercialisation of our research will have a significant impact on improving vision related healthcare worldwide. Our device will fill the gap for early diagnosis/screening of the world’s leading cause of irreversible vision loss, AMD.
Currently, there are many available treatments and decelerators of AMD such as Laser Photocoagulation, Photodynamic Therapy, Anti-Angiogenic Injections (Lucentis), AREDS 2, etc. which are rendered ineffective due to the late diagnosis and irreversibility of AMD. With our device in hospitals and optometry clinics, clinicians would be able to screen for the early signs of eye diseases and prescribe the relevant treatment hence preventing vision loss.
In addition, we hope to create a screening culture for vision health. Eye health is often overlooked and people usually visit an eye-care specialist only after developing certain visual symptoms. However, if our device is placed at every general practitioner and outpatient clinic, combined with the ease-of-use nature of our device, we hope that patients would be able to self-monitor their eye health and seek relevant aid before developing any visual symptoms or vision loss. Hence, prolonging normal vision and improving their quality of life.