This New 3-D Imaging Technique Could Improve Arthritis Treatment
Osteoarthritis is the most common form of arthritis. It occurs when the articular cartilage that covers the ends of our bones is worn down, which results in achy and in some cases immobile joints. At present, there is no cure for osteoarthritis, with the only definitive treatments being cartilage repair surgery, or either partial or total joint replacement.
While there is still no treatment for this painful condition, there have been advances in how it is detected. Traditionally, osteoarthritis is identified via X-ray, which would show a narrowing of the space between the bones of the joint due to a loss of cartilage. The problem with X-ray however, is that it don’t have enough sensitivity to detect subtle changes in the joint over time.
A team of engineers, physicians and radiologists, led by the University of Cambridge, have developed a new algorithm to monitor the joints of patients with arthritis, potentially changing the way the severity of the condition is assessed. The technique, which detects tiny changes in arthritic joints, could enable a greater understanding of how osteoarthritis develops, and allow the effectiveness of new treatments to be assessed more accurately. This can all be done without the need for invasive tissue sampling.
According to Dr. Tom Turmezei of Cambridge's Department of Engineering, "In addition to their lack of sensitivity, two-dimensional X-rays rely on humans to interpret them. Our ability to detect structural changes to identify disease early, monitor progression and predict treatment response is frustratingly limited by this." He further goes on to say that “Using this technique, we'll hopefully be able to identify osteoarthritis earlier, and look at potential treatments before it becomes debilitating. It could be used to screen at-risk populations, such as those with known arthritis, previous joint injury, or elite athletes who are at risk of developing arthritis due to the continued strain placed on their joints."
The technique developed by Turmezei and his colleagues uses images from a computerized tomography (CT) scan. While a CT scan is not normally used to monitor joints, its advantage over X-ray is that it produces detailed images in three dimensions. This semi-automated technique, called Joint Space Mapping (JSM), analyses CT scan images to identify changes in the space between the bones of a joint, an accepted marker for osteoarthritis.
After developing the algorithm with tests on human hip joints, they found that it exceeded the current 'gold standard' of joint imaging with X-ray in terms of sensitivity, showing that it was at least twice as good at detecting small structural changes. Color-coded images produced using the JSM algorithm illustrate the parts of the joint where the space between bones is wider or narrower. According to the researchers, the success of the JSM algorithm demonstrates that 3-D imaging techniques have the potential to be more effective than 2-D imaging. In addition, CT can now be used with very low doses of radiation, meaning that it can be safely used more frequently for the purposes of ongoing monitoring.
"We've shown that this technique could be a valuable tool for the analysis of arthritis, in both clinical and research settings," said Turmezei. "When combined with 3-D statistical analysis, it could also be used to speed up the development of new treatments."
Good news from any one suffering from or predisposed to this often debilitating disease.