MR Spectroscopic imaging of collagen: Tendons and knee menisci

Water molecules associated with collagen have short transverse ( T 2 ) relaxation times. Projection‐reconstruction techniques are able to achieve an echo time ( TE ) much shorter than conventional techniques, allowing imaging of tissues with T 2 < 5 ms. Using these techniques, a conventional 1.5‐T MRI human imaging system can directly image collagen‐associated water from knee menisci and tendons in normal volunteers and patients. Long‐ T 2 suppression improves the contrast between these structures and the surrounding tissue with long‐ T 2 relaxation times. Spectroscopic imaging provides improved lipid/water registration and information about chemical composition and relaxation times. Direct imaging of tendons and menisci may provide more information about these structures and provide a new way to assess both injury and repair.