Contrast-dose relation in first-pass myocardial MR perfusion imaging.
OBJECTIVE
To determine the regime of linear contrast enhancement in human first-pass perfusion cardiovascular magnetic resonance (CMR) imaging to improve accuracy in myocardial perfusion quantification.


METHODS
A total of 10 healthy subjects were studied on a clinical 1.5T MR scanner. Seven doses of Gd-DTPA ranging from 0.00125 to 0.1 mmol/kg of body weight (b.w.) were administered as equal volumes by rapid bolus injection (6 mL/second). Resting periods of 15 minutes were introduced after delivery of Gd doses >0.01 mmol/kg b.w. For each subject, two series of rest perfusion scans were performed using two different multislice saturation-recovery perfusion sequences. Maximum contrast enhancement and maximum upslope were obtained in the blood pool of the left ventricular (LV) cavity and in the myocardium. The range of linear contrast-dose relation was determined by linear regression analysis.


RESULTS
MR signal intensity increased linearly for contrast agent concentrations up to 0.01 mmol/kg b.w. in the LV blood pool and up to 0.05 mmol/kg b.w. in the myocardium. For Gd concentrations exceeding these thresholds the signal intensity response was not linear with respect to the contrast agent dose.


CONCLUSIONS
Quantitative evaluation of cardiac MR perfusion data needs to account for signal saturation in both the LV blood pool and the myocardium.
Utz
Wolfgang
W
Franz Volhard Klinik, Charite Campus Buch, Helios Klinikum-Berlin at the Max Delbrück Center for Molecular Medicine, Wiltbergstrasse 50, 13125 Berlin, Germany. wolfgang.utz@charite.de
Niendorf
Thoralf
T
Wassmuth
Ralf
R
Messroghli
Daniel
D
Dietz
Rainer
R
Schulz-Menger
Jeanette
J
D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D009206:Myocardium
D003287:Contrast Media; D019786:Gadolinium DTPA