T2* effects in the dual-sequence method for high-dose first-pass myocardial perfusion.
OBJECTIVE
To examine whether T2* effects reduce the accuracy of arterial input function (AIF) measurement by the dual-sequence method.


METHODS
The dual-sequence method obtains a low-resolution AIF image and high-resolution myocardial images in each cycle, with suitable T1 weightings. It was modified to assess T2* effects in the low-resolution AIF image (4.8x4.8x10 mm voxels, TE=0.58 msec) by minimizing T1 weighting in that sequence, while the myocardial sequence remained T1-weighted. In 10 patients who underwent perfusion MRI scans (0.5 M Magnevist, 0.1 mmol/kg, 15-ml flush, 7 mL/second right antecubital) the blood signal in the left ventricle (LV) was measured at the bolus peak and compared with the first cycle's fresh magnetization signal.


RESULTS
The bolus peak measured 98%+/-4% (mean+/-SD, N=20) of the value before contrast agent arrival.


CONCLUSIONS
T2* causes insignificant error in the dual-sequence method at the stated parameters.
Gatehouse
Peter
P
Cardiovascular MR Unit, Royal Brompton Hospital, and Imperial College, University of London, United Kingdom. p.gatehouse@rbht.nhs.uk
Lyne
Jonathan
J
Smith
Gillian
G
Pennell
Dudley
D
Firmin
David
D
D000465:Algorithms; D016477:Artifacts; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology