UCSF

Diffusion Imaging has been primarily focused on brain application with limited applications in the knee. One limitation of diffusion imaging in the knee is the long TE (40-60 ms) in most of the sequences that have been used. While this is not a detriment

in brain, it can be a problem in the knee where several tissues have short T2 relaxation times including the cartilage (32 ms) and meniscus (11 ms). Thus imaging of the knee with a short TE diffusion sequence would substantially increase signal to noise, which would in turn be applied to improve diffusion measurements in meniscus and cartilage. Research has shown that diffusion weighted imaging in knee has a strong potential as a biomarker and can act as a new and potent investigation tool for tissue integrity of meniscus and for early diagnosis of cartilage degeneration.

A new sequence for diffusion weighted imaging of knee at 3T has been proposed and evaluated. The proposed stimulated echo with MAPSS acquisition sequence is more signal efficient than the conventional spin echo sequence and can image the whole

knee volume in half the acquisition time compared to the most commonly used line scan sequence. The sequence was tested in phantoms, ex-vivo specimens and in-vivo knees with encouraging results. Further optimization and validation of the sequence is

proposed for successful acquisition of diffusion values in knee cartilage and meniscus in healthy volunteers and osteoarthritis patient cohorts.