Researchers develop non-invasive technique to diagnose rheumatoid arthritis

Infrared light could help detect rheumatoid arthritis and assess treatment effectiveness, according to a new study conducted by a team from the University of Birmingham. Clinicians could use this non-invasive method to diagnose the disease at an early stage.

Rheumatoid arthritis (RA) occurs when one experiences painful inflammation and swelling when the body's immune system attacks the joints.Currently, the methods used for diagnosing the condition are blood tests, physical examinations, ultrasounds and x-rays.

The new technique developed to help diagnose the autoimmune disease was created with 3D digital imaging with infrared spectroscopy. This helped researchers create a 3D image of blood content that is inside a patients' hand. The team from the University of Birmingham's School of Computer Science developed the new method in collaboration with Health Technologies Institute and Rheumatologists in the NIHR Birmingham Biomedical Research Centre.

To test the new method, researchers studied 144 joints from 21 rheumatology patients. In the first step, a patient had to place one hand in the scanner so it can create a 3D model of the hand. It measures the size and contours of the hand. Infrared light is then used. The light coming out through each finger is measured. Oxygenated and deoxygenated blood absorb light in different ways. That is why this technique can be used to detect signs of RA. With the help of the new technique, the team was able to detect inflamed joints. Their results were similar to diagnoses made using ultrasound and clinical examination.

"We know that diagnosing patients with RA early is really important, because early treatment leads to better long-term outcomes," lead author of the study Professor Hamid Dehghani told a news portal. Adding, "The system we have developed offers a low-cost, objective way of detecting the disease and potentially grading how advanced it is. We hope, in time it will enable clinicians to diagnose the disease earlier and offer personalised treatment plans for patients."

The results are published in the Journal of Biomedical Optics.