Deep vein thrombosis using noncontrast‐enhanced MR venography with electrocardiographically gated three‐dimensional half‐fourier FSE: Preliminary experience

Three noncontrast‐enhanced MR venography techniques are presented for assessing deep vein thrombosis (DVT) at 0.5T in patients with metallic implants. Two cardiac‐gated 3D half‐Fourier FSE fresh blood imaging sequences with flow‐refocusing pulses (FR‐FBI) in the read‐out (RO) direction and without FR pulses (non‐FR‐FBI) were developed for slower‐flowing blood. For faster flowing blood, a swap phase‐encode arterial double‐subtraction elimination (SPADE) technique was developed. The three techniques were assessed both quantitatively using signal‐to‐noise (SNR) and contrast‐noise‐ratio (CNR) measurements and qualitatively by subjective image analysis in 15 volunteers. SPADE was compared to FR‐FBI in the pelvic veins and FR‐FBI was compared to non‐FR‐FBI in the thigh and calf veins. Both SPADE and FR‐FBI techniques produced significantly higher SNRs, CNRs, and image quality in each comparative study (P < 0.001). Five patients with metallic implants and confirmed DVT underwent SPADE (pelvic veins) and FR‐FBI (thigh and calf veins) examinations and the results were compared to conventional venography. The SPADE and FR‐FBI images showed all DVTs from all five patients without interference from implant susceptibility artifacts. The excellent image quality produced by both SPADE and FR‐FBI throughout peripheral vasculature demonstrates their promise for detecting DVT in postsurgery patients. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.