BACKGROUNDTo explore the application of MR time-resolved subtracted perfusion imaging to qualitatively and partially quantitatively evaluate blood supply by pulmonary artery in patients with peripheral type lung cancer.

METHODSTwenty-three patients with peripheral type lung cancer proved cytologically or/and histologically underwent MR perfusion study. The time-resolved subtracted imaging which provided the perfusion images in different phases were performed. First-pass time-signal intensity curves of pulmonary artery, descending aorta, lung mass were obtained respectively, and start-time and peak-time of them were compared. The signal enhanced ratio of the masses in pulmonary artery and aorta perfusion phases were calculated respectively.

RESULTSFourteen masses began to enhance during pulmonary circulation phase and reached peak value during systematic-circulation phase, and the average signal change ratio during pulmonary circulation phase was much smaller than that during systematic-circulation phase, indicating their blood supply came both from pulmonary and systematic blood circulation, but mainly from the latter. Seven masses began to enhance and reached peak value during systematic-circulation phase, indicating their blood supply came mainly from systematic blood circulation. Two masses began to enhance and reached peak value during pulmonary-circulation phase, indicating their blood supply came mainly from pulmonary blood circulation.

CONCLUSIONSMR dynamic time-resolved subtracted perfusion imaging is feasible to qualitatively and relatively quantitatively evaluate blood supply of pulmonary artery for peripheral type lung cancer.