In vivo MR imaging of pulmonary arteries of normal and experimental emboli in small animals.
OBJECTIVE
To demonstrate the feasibility of pulmonary MRA in living rodents.


METHODS
A three-dimensional (3D) gradient echo sequence was adapted to perform a time-of-flight (TOF) angiography of rat lung. Angiogram with a spatial resolution of 195 x 228 x 228 microm(3) was acquired in around 33 minutes. The method was then applied in animals before and after pulmonary embolism (PE) induction. Section of the proximal right pulmonary artery was measured and compared between the two populations.


RESULTS
Good quality images were obtained with a contrast-to-noise ratio (CNR) of 9 +/- 3 in the proximal part of the pulmonary artery. Cross-section areas of the right main artery are statistically different before (3.45 +/- 0.69 mm(2)) and after induction of PE (4.3 +/- 0.86 mm(2)).


CONCLUSIONS
This noninvasive tool permits angiogram acquisition at around 200 microm spatial resolution and objective distinction between healthy and embolized arteries.
Lederlin
Mathieu
M
Resonance Magnetique des Systemes Biologiques (RMSB) Unite Mixte Recherche (UMR)5536, Bordeaux, France.
Thiaudiere
Eric
E
Laurent
François
F
Franconi
Jean-Michel
JM
Parzy
Elodie
E
D000818:Animals; D004195:Disease Models, Animal; D017352:Echo-Planar Imaging / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008168:Lung / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D011655:Pulmonary Embolism / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity