MR pulmonary angiography and perfusion imaging: recent advances.

Recent advances in MR pulmonary angiography and MR perfusion imaging are reviewed, focusing on two principal areas of technical development: (1) the availability of MR scanners equipped with enhanced gradient systems; and (2) new trends in MR angiography using gadolinium contrast agents or labeling of blood with an inversion recovery radiofrequency pulse in place of the more traditional methods using naturally flowing spins as the source of intravascular signal. These recent developments in MR have significant potential for clinical imaging of the pulmonary vasculature, particularly for the diagnosis of pulmonary embolism, and are now opening windows to functional MR imaging of the lung.