Rapid Volumetric Quantification of Cartilage Biochemistry with MRI
Detection of changes in cartilage glycosaminoglycan (GAG) content and distribution are vital for early diagnosis of osteoarthritis (OA) and potential treatment monitoring. Glycosaminoglycans (GAG) are long polysaccharide chains that provide lubrication and shock absorption to articular cartilage in the knee. Typical methods of measuring GAG content require specialized MRI hardware or invasive contrast injections. Newer methods such as chemical exchange saturation transfer imaging of GAG (GagCEST) MRI can measure GAG content without the aforementioned restrictions, but it requires long scan times that limit acquisitions to a single slice. Single-slice assessment is not ideal as it may not fully describe the cartilage variation, may miss focal lesions, and may obscure longitudinal changes. To overcome these limitations, we developed and optimized a new GagCEST sequence for rapid volumetric imaging of articular cartilage. Volumetric analysis and decreased scan times enabled by our sequence will advance the clinical utility of GagCEST imaging of articular cartilage. This will provide new insights into OA disease progression and lead to new treatment targets.
Kogan F, Hargreaves B, Gold G. Volumetric Multi-Slice GagCEST Imaging of Articular Cartilage: Optimization & Comparison with T1rho. Magn Reson Med. 2017 Mar;77(3):1134-41.
GagCEST maps of cartilage for 8 slices in the ankle joint of a healthy volunteer acquired in 6 minutes, about the same time as single slice acquisition of prior methods.