Oblique magnetic resonance imaging of the cardiovascular system

Angle-dependent utilization of gradient hardware for oblique MR imaging

A straightforward method for calculating maximum gradient amplitudes for the frequency-encoding, phase-encoding, and section-select functions in oblique magnetic resonance (MR) imaging is presented. The calculated amplitude values depend on the prescribed angulation and on which of the three functions are simultaneously active. The derived expressions are optimal in most cases, and when not optimal, they still offer substantial improvement over calculations that do not incorporate angular information. Both matrix-based and geometric interpretations are presented.

Magnetic resonance imaging of the pediatric thoracic aorta

Magnetic resonance imaging (MRI) is an ideal imaging modality for investigating anomalies of the pediatric thoracic aorta. Its multiplanar capabilities allow imaging along anatomic or perpendicular planes, and clearly show the relationship between the great vessels and the airway structures. The most common pediatric aortic lesions investigated by MRI include vascular rings and coarctation of the descending aorta and its surgical complications. Other obstructive, aneurysmal, and positional anomalies of the aorta are readily demonstrated and quantified. However, precise image prescription is necessary to obtain optimal information. This review discusses and illustrates the common pediatric anomalies and current appropriate choices of imaging techniques.

Correlation between magnetic resonance imaging of the heart and cardiac anatomy

An understanding of anatomy forms the cornerstone for accurate interpretations of pathologic alterations. In this article, we present cardiac magnetic resonance images and the corresponding sections of normal hearts obtained at autopsy and cut in planes parallel and perpendicular to the ventricular septum in addition to the standard anatomic orthogonal planes (coronal, sagittal, and transverse). This correlation demonstrates the ability of magnetic resonance imaging to display cardiac anatomy accurately and noninvasively. Because magnetic resonance imaging provides excellent contrast between flowing blood and cardiac walls and has the capacity to provide direct images in multiple planes without inherent difficulties, this procedure has advantages over other currently available imaging techniques.