Usefulness of lower extremity MR venography in 2D TOF sequence with fat suppression techniques and MTC, and study of different warming procedures

We evaluated the effect of fat suppression techniques (fatsat) and magnetization transfer contrast (MTC) for MR venography (MRV) using the 2D TOF sequence in the lower extremities. In addition, the improvement of vessel conspicuity resulting from three different warming procedures was evaluated. Three combinations of fatsat and MTC were performed. Both the signal intensity ratio (SIR) and contrast-to-noise ratio (CNR) were measured at ROIs of vein, fat, and muscle in knee. The vessel conspicuity of MIP was evaluated by three radiologists. The experimental results indicated that MTC pulses did not affect fatsat. The combination techniques of fatsat and MTC improved SIR (≅13%) and CNR (≅5%) of the vein compared with techniques using fatsat only. The continuous warming procedure was better than temporary warming in terms of vessel conspicuity. We conclude that the combined techniques of fatsat and MTC with the continuous warming procedure were clearly useful for MRV using the 2D TOF sequence in the lower extremities. (author)