Eye exams can provide crucial information about kidney health, study finds

3D eye scans may reveal critical clues about kidney health that could help track disease progression, research suggests. This advance could revolutionize the monitoring of kidney diseases, which often progress without symptoms at an early stage.

Experts say the technology has the potential to aid early diagnosis, as current screening tests cannot detect the disease until half of kidney function has been lost.

Researchers used highly magnified images to detect changes in the retina, the layer of tissue at the back of the eye that detects light and sends signals to the brain. They found that the images provide a quick, non-invasive way to monitor kidney health.

The eye is the only part of the body where it is possible to visualize a key process called microvascular circulation. This blood flow through the body’s smallest vessels is often affected in kidney disease.

Researchers at the University of Edinburgh investigated whether 3D images of the retina, taken using a technology called optical coherence tomography (OCT), could be used to accurately identify and predict the progression of kidney disease.

OCT scanners, used by most opticians, use light waves to create a cross-sectional image of the retina, displaying each individual layer, within minutes.

The team examined OCT images of 204 patients at various stages of kidney disease, including transplant patients, alongside 86 healthy volunteers. They found that patients with chronic kidney disease had thinner retinas than healthy volunteers. The study also showed that retinal thinning progressed as kidney function decreased.

These changes were reversed when kidney function was restored following successful transplantation. Patients with the most severe form of the disease who received a kidney transplant experienced rapid thickening of their retina after surgery.

More and more people are at risk of kidney disease, often caused by other conditions that put pressure on the kidneys, including diabetes, high blood pressure and obesity.

With further research, regular eye checks could one day facilitate early detection and monitoring to prevent the disease from progressing. Experts say it could also allow patients to make lifestyle changes to reduce the risk of health complications.

The technology, supported by Heidelberg Engineering’s imaging platform, could also contribute to the development of new drugs, according to the research team. To do this, it could measure changes in the retina that indicate whether, and how, the kidney responds to potential new treatments.

The researchers say further studies, including longer-term clinical trials in larger groups of patients, are needed before the technology can be used routinely. In the UK, an estimated 7.2 million people live with chronic kidney disease, more than 10% of the population. It costs the NHS around £7 billion every year.

The study is published in Natural communications.

Dr Neeraj (Bean) Dhaun, Professor of Nephrology at the University of Edinburgh’s Center for Cardiovascular Sciences, said: “We hope that this research, which shows that the eye is a useful window into the kidney, will help to identify more people with early cancer. kidney disease, providing the opportunity to begin treatments before it progresses.

“It also offers potential for new clinical trials and the development of drug treatments for a chronic disease that, until now, has proven extremely difficult to treat.”

Dr Aisling McMahon, executive director of research and policy at Kidney Research UK, said: “Patients with kidney disease often face invasive procedures to monitor their kidney health, often in addition to grueling treatments like dialysis. . »

“This fantastic research shows the potential for a much gentler way to monitor kidney health. We continue to support the team as they study whether their approach could also be used to diagnose and intervene earlier in kidney disease. ”