A Manganese Alternative to Gadolinium for MRI Contrast.

Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used to diagnose soft tissue and vascular abnormalities. However, safety concerns limit the use of iodinated and gadolinium (Gd)-based CT and MRI contrast media in renally compromised patients. With an estimated 14% of the US population suffering from chronic kidney disease (CKD), contrast media compatible with renal impairment is sorely needed.

Quadruple inversion-recovery b-SSFP MRA of the abdomen: initial clinical validation.

The purpose of this study is to assess the image quality and diagnostic accuracy of non-contrast quadruple inversion-recovery balanced-SSFP MRA (QIR MRA) for detection of aortoiliac disease in a clinical population. QIR MRA was performed in 26 patients referred for routine clinical gadolinium-enhanced MRA (Gd-MRA) for known or suspected aortoiliac disease. Non-contrast images were independently evaluated for image quality and degree of stenosis by two radiologists, using consensus Gd-MRA as the reference standard.

Sagittal fresh blood imaging with interleaved acquisition of systolic and diastolic data for improved robustness to motion.

Purpose: To improve robustness to patient motion of "fresh blood imaging" (FBI) for lower extremity noncontrast MR angiography.

Methods: In FBI, two sets of three-dimensional fast spin echo images are acquired at different cardiac phases and subtracted to generate bright-blood angiograms. Routinely performed with a single coronal slab and sequential acquisition of systolic and diastolic data, FBI is prone to subtraction errors due to patient motion.

Comparison of nonenhanced MR angiographic subtraction techniques for infragenual arteries at 1.5 T: a preliminary study.

Purpose: To evaluate diagnostic performance of three nonenhanced methods: variable-refocusing-flip angle (FA) fast spin-echo (SE)-based magnetic resonance (MR) angiography (variable FA MR) and constant-refocusing-FA fast SE-based MR angiography (constant-FA MR) and flow-sensitive dephasing (FSD)-prepared steady-state free precession MR angiography (FSD MR) for calf arteries, with dual-injection three-station contrast material-enhanced MR angiography (gadolinium-enhanced MR) as reference.

Materials And Methods: This prospective study was institutional review board approved and HIPAA compliant, with informed consent. Twenty-one patients (13 men, eight women; mean age, 62.

Noncontrast MR angiography for comprehensive assessment of abdominopelvic arteries using quadruple inversion-recovery preconditioning and 3D balanced steady-state free precession imaging.

Purpose: To develop a noncontrast magnetic resonance angiography (MRA) method for comprehensive evaluation of abdominopelvic arteries in a single 3D acquisition.

Materials And Methods: A noncontrast MRA (NC MRA) pulse sequence was developed using four inversion-recovery (IR) pulses and 3D balanced steady-state free precession (b-SSFP) readout to provide arterial imaging from renal to external iliac arteries. Respiratory triggered, high spatial resolution (1.

Tailoring the flow sensitivity of fast spin-echo sequences for noncontrast peripheral MR angiography.

There has recently been renewed interest in noncontrast techniques for peripheral MR angiography following the discovery of an association between gadolinium-based contrast agents and nephrogenic systemic fibrosis in patients with renal insufficiency. The "fresh blood imaging" technique proposed by Miyazaki et al. involves the subtraction of two three-dimensional fast spin-echo image sets, one acquired in systole, when the arteries appear dark due to flow-related dephasing, and the other obtained in diastole, when the arteries are brighter.

Three-dimensional electrocardiographically gated variable flip angle FSE imaging for MR angiography of the hands at 3.0 T: initial experience.

After institutional review board approval and informed consent were obtained for this HIPAA-compliant investigation, a three-dimensional electrocardiographically gated variable flip angle (VFA) fast spin-echo magnetic resonance (MR) angiography technique was evaluated as an unenhanced method for imaging hand arteries in 13 subjects (including four patients) at 3.0 T; this included evaluation of vessel visualization with warming and cooling in seven subjects. Examinations were evaluated for image quality and vessel conspicuity.