CONTRAST-ENHANCED, ULTRAFAST 3D PULMONARY MR-ANGIOGRAPHY IN A SINGLE BREATH-HOLD - INITIAL ASSESSMENT OF IMAGING PERFORMANCE

An ultrafast three-dimensional (3D) sequence was developed, enabling t he acquisition of 44 contiguous 2.0- to 2.2-mm thin sections, during i ntravenous application of paramagnetic contrast, in a single breath-ho ld. To estimate the potential clinical usefulness, images were assesse d qualitatively and quantitatively with regard to visibility of main, lobar, segmental, and subsegmental pulmonary arteries. Five volunteers were examined using a 192 x 192 matrix with an imaging time of 23 sec onds and five other volunteers with a 160 x 160 matrix (18 seconds). E ach volunteer was imaged in apnea and during shallow respiration. The breath-held 23-second scans revealed excellent image quality and near complete visualization of central and segmental, as well as 81% of sub segmental, pulmonary arteries. Imaging time can be shortened to 18 sec onds with only marginal loss in visualization performance (P < .05). R espiratory motion was found to cause significant worsening of image qu ality and vessel detectability. To maintain relevance in a clinical se tting, imaging time can be minimized at the cost of a reduction in spa tial resolution.