title: Quiescent-interval single-shot unenhanced magnetic resonance angiography of peripheral vascular disease: Technical considerations and clinical feasibility.
abstract: We performed technical optimization followed by a pilot clinical study of quiescent-interval single-shot MR angiography for peripheral vascular disease. Quiescent-interval single-shot MR angiography acquires data using a modified electrocardiographic (ECG)-triggered, fat suppressed, two-dimensional, balanced steady-state, free precession pulse sequence incorporating slice-selective saturation and a quiescent interval for maximal enhancement of inflowing blood. Following optimization at 1.5 T, a pilot study was performed in patients with peripheral vascular disease, using contrast-enhanced MR angiography as the reference standard. The optimized sequence used a quiescent interval of 228 ms, alpha/2 catalyzation of the steady-state magnetization, and center-to-out partial Fourier acquisition with parallel acceleration factor of 2. Spatial resolution was 2-3mm along the slice direction and 0.7-1mm in-plane before interpolation. Excluding stented arterial segments, the sensitivity, specificity, and positive and negative predictive values of quiescent-interval single-shot MR angiography for arterial narrowing greater than 50% or occlusion were 92.2%, 94.9%, 83.9%, and 97.7%, respectively. Quiescent-interval single-shot MR angiography provided robust depiction of normal peripheral arterial anatomy and peripheral vascular disease in less than 10 min, without the need to tailor the technique for individual patients. Moreover, the technique provides consistent image quality in the pelvic region despite the presence of respiratory and bowel motion.
authors.affiliation: Department of Radiology, NorthShore University HealthSystem, Evanston, Illinois, USA. redelman@northshore.org
authors.forename: Robert R
authors.initials: RR
authors.lastname: Edelman
authors.forename: John J
authors.initials: JJ
authors.lastname: Sheehan
authors.forename: Eugene
authors.initials: E
authors.lastname: Dunkle
authors.forename: Nancy
authors.initials: N
authors.lastname: Schindler
authors.forename: James
authors.initials: J
authors.lastname: Carr
authors.forename: Ioannis
authors.initials: I
authors.lastname: Koktzoglou
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007866:Leg / Q000098:blood supply; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity