The new imaging technique we use supports early detection of diabetic eye disease.
The shape of diabetic retinopathy. The image shows a diabetic retina and depicts the tiny blood vessels that can be damaged as a result of diabetes (Image by Dr Dong An).
Diabetes remains the leading cause of irreversible blindness in Australian adults, yet evidence shows us that early detection and timely treatment can prevent the majority of diabetes-related vision loss.
Diabetes damages blood vessels all over the body including those int eh eyes. In diabetic eye disease, sugar blocks and damages tiny blood vessels (capillaries) of the retina (the light-sensitive layer of tissues int eh back of your eye).
Until recently, our understanding of the earliest blood vessel changes the characterise diabetic eye disease such as diabetic retinopathy, prior to vision loss, has been limited by the availability of precise retinal imaging tools.
The limitation has been a significant contributing factor in the delay and difficulty of denying patients with diabetes that are at high risk of vision loss.
Even with advances in state-of-the-art cameras and colour photography technology in recent times, it has not been possible to detect damage with these tiny capillaries that have a diameter of 7-8 microns (one micron is equivalent to one one-thousandth of a millimetre).
That is until recently, when we here at the Lions Eye Institute developed a high resolution imaging technique to measure the variation in capillary size, using Optical Coherence Tomography Angiography (OCTA). It is now possible to precisely image the retinal capillaries in a clinical setting using this non-invasive technology, that is – it does not require a dye injection.
Our research group has pioneered much of the work on OCTA over the past five years through technology validation and also the development of prototype OCTA device in partnership with the Department of Biomedical Engineering in Simon Fraser university, British Columbia, Canada. In doing so we are addressing a major gap in the clinical management of diabetic eye disease and the occurrence of sight-threatening complications.
More broadly, as a result of the advances in early detection imaging techniques, this platform will expand its collaboration to include detecting at risk children from more widespread diseases involving the brain and kidneys.
The team behind the project:
The principal investigators for this study will be Dr. Balaratnasingam and Professor Yu.
Dr. Balaratnasingam is a clinician-scientist who holds a PhD and has published over 100 peer-reviewed manuscripts and eight book chapters. He is a consultant ophthalmologist who sub-specialises in retina diseases. His principal research interest is a diabetic retinopathy and he is currently the chief investigator for two clinical trials in this field. Dr. Balaratnasingam regularly speaks at national and international meetings in the field of retinal diseases ans in 2017 was invited to present at the highly prestigious International Congress on OCT Angiography, En Face and Advances in OCT.
Professor Yu is an internationally renowned expert in the field of retinal vascular diseases. He has made major contributions to the understanding of mechanisms that control and maintain retinal oxygenation in health and disease. These findings have had wise applications to our current understanding of conditions that manifest with retinal ischaemia such as diabetic retinopathy , retinal vein occlusion and retinopathy of prematurity.
Over the past three decades, Professor Yu has also established a world class research team comprised of histologists, physiologists, engineers and clinicians that have made important bench-to-bedside translational breakthroughs. As an exemplar, Professor Yu and his team were responsible for developing the XEN stent microfistula that is now considered one of the first-line surgical treatments for Glaucoma. Approximately 100,000 patients have now undergone this procedure worldwide.
Professor Elizabeth Davis and Professor Time Jones are internationally-renowned clinical and research experts in pediatric diabetes. Collectively they have published over 250 journal articles in the field of pediatric endocrinology. Professor Davis is the head of the department of Endocrinology and Diabetes at PCH and currently oversees the organisational aspects of the ophthalmic screening programmes for children with diabetes.
Dr Antony Clark is a clinician-scientist and an investigator in this study. Dr Clark is a consultant ophthalmologist with sub-specialty expertise in a pediatric ophthalmology and holds a PhD. Other investigators in this study will include Professor Cringle and Associate Professor Paula Yu, who are highly respected vascular physiologists with over 200 peer-reviewed publications.
Technical assistance for retinal imagine and image analysis was provided by Mr. Dean Darcey, Mr. Macdara O’Murchu and Dr. Andrew Mehnert.
