Phase-Adjusted Fresh Blood Imaging (PA-FBI) as a Non-Contrast Peripheral MRA Technique
Miyazaki M, Kanazawa H, Okigawa T, Wada H, Nomitsu Y, Urata J, Kassai Y, Machida Y, Ichinose N
Toshiba America Medical Systems, Toshiba Medical Systems Corp.
Flow effects in non-contrast enhanced flow-spoiled fresh-blood imaging (FS-FBI) were investigated in terms of signal coherence. In order to gain arterial signal intensity, an ideal condition is to have a large signal difference between diastole and systole. However, to obtain dark blood in systole, a stronger read-out (RO) spoiler pulse was applied and N/2 artifacts appeared in a result. A new method is proposed to maximize the signal difference in diastole and systole, using two coherent pathways in phase changes as a simple model. Application of RF phase offset permits significant improvement in arterial depiction with less N/2 artifacts.