Interstudy repeatability of self‐gated quantitative myocardial perfusion MRI

Abstract

Purpose To evaluate the inter-study repeatability of multi-slice quantitative cardiovascular magnetic resonance myocardial blood flow (MBF), myocardial perfusion reserve (MPR), and extracellular volume (ECV). A unique saturation recovery self-gated acquisition was used for the perfusion scans. Materials and Methods An ungated golden angle radial turboFLASH pulse sequence was used to scan 10 subjects on two separate days on a 3T scanner. A single saturation pulse was followed by a set of 4 slices. Rest and hyperemia scans were acquired during free breathing. The images were reconstructed using an iterative algorithm with spatiotemporal constraints. The ungated images were retrospectively binned (self-gated) into near-systole and near-diastole. Deformable registration was performed to adjust for respiratory and residual cardiac motion, and the data was fit with a Fermi model to estimate the inter-study repeatability of quantitative self-gated MBF and MPR. Results The coefficient of variation (CoV) of the territorial MPR using the self-gated near-systole data was 18.6%. The self-gated near-diastole data gave less good CoV of MPR, equal to 46.2%. For MBFs, and using smaller (segmental) regions, the CoVs were 20.1% and 22.7% for the estimation of myocardial blood flow at stress and rest respectively using the self-gated near-systole data. The self-gated near-diastole data gave CoV=48.6% and 44.9% for stress and rest. Conclusion The self-gated free breathing technique for quantification of myocardial blood flow showed good repeatability for near-systole, with results comparable to published studies on inter-study repeatability of quantitative myocardial perfusion MRI using ECG-gating and breath-holds. Self-gated near-diastole data results were less repeatable.

Evaluation of quantitative CMR perfusion imaging by comparison with simultaneous 15O-water-PET

“…[43][44][45][46][47] Direct comparison with the reproducibility of PET-based myocardial perfusion measurements is hampered by different measures of repeatability used in different studies and wide time ranges between the repeated measures in some studies. However, the repeatability coefficients reported in some MRI studies 44,47 are somewhat higher and the ICC somewhat lower 44,46 than in the previously mentioned PET-studies. 41,42 Morton et al 21 reported weak correlations for absolute perfusion values when comparing rest and stress perfusion values separately (r = 0.32 and r = 0.37, respectively).…”

Influence of contrast agent dispersion on bolus‐based MRI myocardial perfusion measurements: A computational fluid dynamics study

“…In fact, several MRI studies reported an underestimation of MBF . In those studies, the MBF values were analyzed with regard to issues of quantification algorithms, applied MRI signal intensity corrections, interstudy repeatability, or motion correction .…”

“…65 In fact, several MRI studies reported an underestimation of MBF. 3,[66][67][68][69][70][71][72][73] In those studies, the MBF values were analyzed with regard to issues of quantification algorithms, 69 applied MRI signal intensity corrections, 70 interstudy repeatability, 71 or motion correction. 72 For hyperemia, MBF underestimation was more pronounced in comparison to microsphere perfusion measurements 70,73 ; however, it is well-known that the microsphere technique somewhat overestimates MBF in regions of high flow, and underestimates MBF in regions of low flow.…”

“…The comparison of our results with existing PET data is also not straightforward. In Miller, 17 Even though in several of these studies the obtained MBF values are calculated on a regional 69,[71][72][73]75 or pixel-by-pixel basis, 3 an association of the quantified tissue voxel or segment with a specific coronary flow territory is not performed. Hence, an assessment of quantified MBF values in relation to the distance traveled by CA between the locations of AIF and perfusion quantification is difficult.…”

Estimating extraction fraction and blood flow by combining first-pass myocardial perfusion and T1 mapping results

“…ECV has been validated as a marker of myocardial fibrosis and infarction. Studies have shown good accuracy and repeatability for ECV estimation using T1 mapping (20)(21)(22). Over these years, pharmacokinetic modelling of myocardial perfusion has also evolved.…”