New MRI Technique Detects OA Before Symptom Onset
BY LAUREN UZDIENSKI, JANUARY 29, 2009
Researchers at Stanford University are developing sodium MRI, an imaging technique that can identify signs of cartilage deterioration up to decades before a patient exhibits symptoms of osteoarthritis.
A standard MRI emits electromagnetic energy that excites protons in water molecules. This activity is what produces the image, but it only shows the existence of the cartilage, not its quality. Sodium MRI can show quality by depicting the presence of glycosaminoglycan, a chondroitin that occurs in a complex with sodium. Sodium MRI is not itself a new technology, but software and magnets strong enough to get the glycosaminoglycan to respond in humans were the contribution of the Stanford team.
So far, Stanford has been evaluating the use of a sodium MRI in patients with ACL tears, which are often a precursor to OA. Stanford has found evidence of significant losses of glycosaminoglycan in all of about a dozen patients who underwent the scan, though a standard MRI showed no evidence of cartilage damage.
These results echo commentary from the New York Times late last year: routine MRIs may provide only limited information. The sodium MRI represents a more refined imaging technique, that could, as Stanford's researchers say, "[accelerate] diagnoses" and offer patients options earlier in the continuum of care.
