Project 454733

Osteoarthritis (OA) is the most common joint disease, worldwide affecting 9.6% of men and 18.0% of women over 60 years old, and is a major source of disability, pain, and socioeconomic cost. Recent imaging studies have shown that inflammation may play a major role in the disease process of knee OA. Although magnetic resonance imaging (MRI) can measure inflammation with a high degree of accuracy, it is expensive and remains inaccessible to researchers, clinicians, and patients. Ultrasound (US) can measure inflammation with higher resolution than MRI but suffers major drawbacks due to the quality of the scan being highly dependent on the operator. However, 3-dimensional (3D) US does not suffer from this limitation and may present an alternative to MRI for measuring knee inflammation in patients with knee OA. Before we can use 3DUS for measuring inflammation, we must first determine whether it is at least as reliable and accurate as MRI. Therefore, in the current project, we will determine the measurement properties of 3DUS for imaging of synovitis (inflammation) in knee OA patients. After imaging, manual segmentation (outlining the inflammation on US and MRI images) will create 3D models of synovitis which can be directly compared. We will also determine the error associated with measuring synovitis with 3DUS when no change has occurred, and after patients receive treatment. In this way, we will develop a comprehensive understanding of how accurate 3DUS is for measuring inflammation and answer the question of whether it can replace MRI in the measurement of synovitis. If 3DUS can quantify synovitis in knee OA at least as well as MRI, it could present a cost-effective and readily accessible method of sophisticated knee imaging, a powerful tool for researchers, clinicians, and patients.