A noncontrast-enhanced pulse sequence optimized to visualize human peripheral vessels

The purpose of this paper is to present a pulse sequence optimized to visualize human peripheral vessels. The optimized MR technique is a 3D multi-shot balanced non-SSFP gradient echo pulse sequence with fat suppression. Several imaging parameters were adjusted to find the best compromise between the contrast of vascular structures and muscle, fat, and bone. Most of the optimization was performed in the knee and calf regions using multi-channel SENSE coils. To verify potential clinical use, images of both healthy volunteers and volunteers with varicose veins were produced. The balanced non-SSFP sequence can produce high-spatial-resolution images of the human peripheral vessels without the need for an intravenous contrast agent. Both arteries and veins are displayed along with other body fluids. Due to the high spatial resolution of the axial plane source or reconstructed images, the need for procedures to separate arteries from veins is limited. We demonstrate that high signals from synovial joint fluid and cystic structures can be suppressed by applying an inversion prepulse but at the expense of reduced image signal-to-noise and overall image quality.