Long-T2 suppression RF pulses for MRI of short and ultrashort T2 components
Ultra-short echo time (UTE) and zero echo time (ZTE) magnetic resonance imaging (MRI) allows for visualization of semi-solid tissues with very short T2 relaxation times. This tissues, which include collagen-rich tisuses such as tendons, ligaments and menisci, as well as calcifications, myelin, periosteum and cortical bone, are normally invisible with conventional MRI techniques.
Long-T2 species suppression is required for many UTE/ZTE applications to improve the contrast of short-T2 species. This package provides descriptions and Matlab files for designing long-T2 RF suppression pulses to improve visualization of semi-solid tissues, as well as providing some sample pulses.
3D UTE knee images (a) without suppression and (b,c,d) with a dual-band long-T2 suppression pulse. The menisci and patellar tendon are particularly visible in (b), (c), and (d) (long, thin arrows). (d) also shows the iliotibial band and the anterior cruciate ligament (dashed arrows), as well as thickened tibial cortex in the weight-bearing region of the knee (double arrow). There is some fat suppression failure around the patella (short, fat arrows in (b)).
Please see the following reference for more information:
Larson PEZ, Gurney PT, Nayak K, Gold GE, Pauly JM, Nishimura DG. "Designing long-T2 suppression pulses for ultrashort echo time imaging." Magnetic Resonance in Medicine 2006; 56: 94-103.