Importance of Parametric Mapping and Deconvolution in Analyzing Magnetic Resonance Myocardial Perfusion Images

Abstract

: Interobserver agreement was 57% and 81% and accuracy 53% and 81%, for visual and for parametric map analysis, respectively. For deconvolution parameters, a linear relationship y = 371 + 1.27x, r = 0.78 was obtained between rMBF calculated by ARMA and the radioactive microsphere blood flow. Moreover, the fast and robust parametric mapping of rMBF by the discrete ARMA method allows MR evaluation of myocardial perfusion independently of hemodynamic conditions.

Multicompartmental analysis of late contrast enhancement in areas of myocardial infarction supplied by chronically occluded coronary arteries

“…In the present study, MRI images from a single slice were recorded at a rate of only one frame per minute and up to the 15th minute following injection. This had the additional advantage of avoiding the first minute following injection, during which Gd-concentrations are high and, thus, poorly correlated with signal intensity (16,17).…”

“…2, which relies on the general assumption that DTPA has both interstitial and vascular distribution compartments within the myocardium (13,14); 2) postulating that relaxation rates are comparable in all compartments and that exchange rates between compartments are rapid; and 3) given the assumption of a sufficiently high correlation between signal intensity and Gd concentration (no image was recorded during the first minute following injection, where Gd-concentrations are high and poorly correlated with signal intensity (15)(16)(17)). This assumption is comforted by the linear relationship, which was documented between the expected concentration of Gd (those around 1 mmol.L -1 or lower) and the signal intensity provided by the IR-GRE sequence in tubes filled in with growing concentrations of Gd-DTPA (Fig.…”

Myocardial First Pass Perfusion Imaging With Gadobutrol

“…These complex algorithms such as the empirical gamma variate fit are sensitive to noise and have been shown to be reliable only for relatively high SNR (ϳ50) 27 and CNR (ϳ6). 28 Additionally, a minimum of 6 consecutive data points are required during the downslope of the contrast agent for a reliable calculation. 29 In contrast to this, a linear fit on the upslope has proven to be the most reliable semiquantitative parameter in numerous studies and seems to be very sensitive for alterations in myocardial perfusion.…”

In vivo quantification of regional myocardial blood flow: Validity of the fast‐exchange approximation for intravascular T1 contrast agent and long inversion time

“…In a previous study we tested a prototypic blood-pool contrast agent, CMD-A2-Gd-DOTA (P717; Guerbet, Aulnay-sous-Bois, France) for in vivo quantification of rMBF and the myocardial perfusion reserve (MPR) (18). The imaging protocol, which was designed to be as close as possible to the clinical setting, in which hypoperfused myocardial territories are diagnosed by visual inspection of the image series, involved a rather long TI (176 ms) to enhance contrast (18). Questions then arose regarding the possible confounding effects of water exchange on the quantification of perfusion parameters from these data.…”