Ethan M. Johnson1,
Jinyi Qi2, Urvi Vyas1, Kim R. Butts Pauly1,
John M. Pauly1
1Stanford
University, Stanford, CA, United States; 2UC Davis, Davis, CA,
United States
Pulse sequences using very short echo times (UTE, CUTE, DUTE, etc.) have been applied variously to image tissues with short spin-spin relaxation (<I>T</I>2) times. With consideration of the consequences short-<I>T</I>2 times have for excitation and encoding, a UTE-style pulse sequence capable of visualising bone and other fast-relaxing structures is developed. The acquired images show features that facilitate tissue classification, which is useful, e.g., for MR-PET and high-frequency focussed-ultrasound. To demonstrate, bone, soft tissue and air are classified from 1/<I>T</I>2 and signal level, from which a linear attenuation coefficient map useful for PET reconstruction is generated.