Quantitative 3D myocardial perfusion with an efficient arterial input function

Abstract

Purpose The purpose of this study was to further develop and combine several innovative sequence designs to achieve quantitative 3D myocardial perfusion. These developments include an optimized 3D stack‐of‐stars readout (150 ms per beat), efficient acquisition of a 2D arterial input function, tailored saturation pulse design, and potential whole heart coverage during quantitative stress perfusion. Theory and Methods All studies were performed free‐breathing on a Prisma 3T MRI scanner. Phantom validation was used to verify sequence accuracy. A total of 21 subjects (3 patients with known disease) were scanned, 12 with a rest only protocol and 9 with both stress (regadenoson) and rest protocols. First pass quantitative perfusion was performed with gadoteridol (0.075 mmol/kg). Results Implementation and quantitative perfusion results are shown for healthy subjects and subjects with known coronary disease. Average rest perfusion for the 15 included healthy subjects was 0.79 ± 0.19 mL/g/min, the average stress perfusion for 6 healthy subject studies was 2.44 ± 0.61 mL/g/min, and the average global myocardial perfusion reserve ratio for 6 healthy subjects was 3.10 ± 0.24. Perfusion deficits for 3 patients with ischemia are shown. Average resting heart rate was 59 ± 7 bpm and the average stress heart rate was 81 ± 10 bpm. Conclusion This work demonstrates that a quantitative 3D myocardial perfusion sequence with the acquisition of a 2D arterial input function is feasible at high stress heart rates such as during stress. T1 values and gadolinium concentrations of the sequence match the reference standard well in a phantom, and myocardial rest and stress perfusion and myocardial perfusion reserve values are consistent with those published in literature.

Whole‐heart, ungated, free‐breathing, cardiac‐phase‐resolved myocardial perfusion MRI by using Continuous Radial Interleaved simultaneous Multi‐slice acquisitions at sPoiled steady‐state (CRIMP)

“…These studies sequentially acquire the slice groups at different cardiac phases. The 3D acquisitions [9][10][11][12] allow for acquisition of multiple slices at the same cardiac phase; however, the long temporal footprint (150-300 ms) may not be optimal for systolic imaging.…”

Improved 3D real‐time MRI of speech production

“…stack-of-stars) approach due to its similar distribution in 3D k-space. 27,46 This data-sampling scheme has the benefit of mitigating motion-induced temporal blurring, especially with respect to radial trajectory that has been proved to be robust to motion artifacts. 47 Data sampling and constrained reconstruction are intertwined.…”

“…The proposed sampling strategy may also benefit a 3D stack‐of‐radial (a.k.a. stack‐of‐stars) approach due to its similar distribution in 3D k ‐space 27,46 . This data‐sampling scheme has the benefit of mitigating motion‐induced temporal blurring, especially with respect to radial trajectory that has been proved to be robust to motion artifacts 47 …”

Artifact reduction in free‐breathing, free‐running myocardial perfusion imaging with interleaved non‐selective RF excitations

“…Only 3 slices were acquired during myocardial perfusion imaging. Additional studies are required to explore increasing slice coverage through simultaneous multi-slice 12,13 and 3-dimensional myocardial perfusion 11,[22][23][24][25] imaging. Myocardial blood flow (MBF) was not quantified for both free-running SPGR with and without non-selective RF.…”