Similarity‐driven multi‐dimensional binning algorithm (SIMBA) for free‐running motion‐suppressed whole‐heart MRA

• Published in: Magnetic resonance in medicine Vol. 86; no. 1; pp. 213 - 229
• Main Authors: Heerfordt, John, Whitehead, Kevin K., Bastiaansen, Jessica A. M., Di Sopra, Lorenzo, Roy, Christopher W., Yerly, Jérôme, Milani, Bastien, Fogel, Mark A., Stuber, Matthias, Piccini, Davide
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.07.2021
• Subjects: 3D radial; Algorithms; Blood; Child; clustering; Coronary artery; Coronary vessels; Coronary Vessels - diagnostic imaging; Data acquisition; ferumoxytol; free‐running; Gating; Heart; Humans; Image contrast; Image quality; Image reconstruction; Imaging, Three-Dimensional; Interfaces; Magnetic Resonance Angiography; Motion; Myocardium; noncontrast MRA; Running; Sharpness; Similarity; Veins & arteries; whole heart; 3D radial; free-running; clustering; whole heart; ferumoxytol; noncontrast MRA
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/mrm.28713

Purpose Whole‐heart MRA techniques typically target predetermined motion states, address cardiac and respiratory dynamics independently, and require either complex planning or computationally demanding reconstructions. In contrast, we developed a fast data‐driven reconstruction algorithm with minimal physiological assumptions and compatibility with ungated free‐running sequences. Theory and Methods We propose a similarity‐driven multi‐dimensional binning algorithm (SIMBA) that clusters continuously acquired k‐space data to find a motion‐consistent subset for whole‐heart MRA reconstruction. Free‐running 3D radial data sets from 12 non‐contrast‐enhanced scans of healthy volunteers and six ferumoxytol‐enhanced scans of pediatric cardiac patients were reconstructed with non‐motion‐suppressed regridding of all the acquired data (“All Data”), with SIMBA, and with a previously published free‐running framework (FRF) that uses cardiac and respiratory self‐gating and compressed sensing. Images were compared for blood–myocardium sharpness and contrast ratio, visibility of coronary artery ostia, and right coronary artery sharpness. Results Both the 20‐second SIMBA reconstruction and FRF provided significantly higher blood–myocardium sharpness than All Data in both patients and volunteers (P < .05). The SIMBA reconstruction provided significantly sharper blood–myocardium interfaces than FRF in volunteers (P < .001) and higher blood–myocardium contrast ratio than All Data and FRF, both in volunteers and patients (P < .05). Significantly more ostia could be visualized with both SIMBA (31 of 36) and FRF (34 of 36) than with All Data (4 of 36) (P < .001). Inferior right coronary artery sharpness using SIMBA versus FRF was observed (volunteers: SIMBA 36.1 ± 8.1%, FRF 40.4 ± 8.9%; patients: SIMBA 35.9 ± 7.7%, FRF 40.3 ± 6.1%, P = not significant). Conclusion The SIMBA technique enabled a fast, data‐driven reconstruction of free‐running whole‐heart MRA with image quality superior to All Data and similar to the more time‐consuming FRF reconstruction.