A combined H-1 perfusion/He-3 ventilation NMR study in rat lungs

The assessment of both pulmonary perfusion and ventilation is of crucial im portance for a proper diagnosis of some lung diseases such as pulmonary emb olism, In this study, we demonstrate the feasibility of combined magnetic r esonance imaging lung ventilation and perfusion performed serially in rat l ungs. Lung ventilation function was assessed using hyperpolarized He-3, and lung perfusion proton imaging was demonstrated using contrast agent inject ion, Both imaging techniques have been implemented using projection-reconst ruction sequences with free induction decay signal acquisitions. The study focused on fast three-dimensional (3D) data acquisition. The projection-rec onstruction sequences used in this study allowed 3D data set acquisition in several minutes without highperformance gradients. 3D proton perfusion/hel ium ventilation imaging has been demonstrated on an experimental rat model of pulmonary embolism showing normal lung ventilation associated with lung perfusion defect. Assuming the possibility, still under investigation, of s howing lung obstruction pathologies using He-3 imaging, these combined perf usion/ventilation methods could play a significant clinical role in the fut ure for diagnosis of several pulmonary diseases, (C) 1999 Wiley-Liss, Inc.