MR of Hemorrhage : A New Approach 751

Using a modification of the partial saturation (PS) pulse sequence, we developed an MR method that permits the acquisition of highly T1and T2-weighted images of the head and body in as little as 10 sec. The PS images, which were acquired at 0.6 T in a series of six patients with acute and subacute hemorrhage, showed a striking reduction in the signal intensity of hemorrhagic lesions. This effect, which is related to bulk magnetic susceptibility variations, was either minimal or absent on conventional T1and T2-weighted spin-echo (SE) images. Our results suggest that high-field systems are not needed in order to image acute and subacute hemorrhage.