Prospective self‐gating for swallowing motion: A feasibility study in carotid artery wall MRI using three‐dimensional variable‐flip‐angle turbo spin‐echo

Abstract

Three-dimensional (3D) black-blood MRI is a promising noninvasive imaging technique for the assessment of atherosclerotic carotid artery disease. However, this technique is inherently susceptible to motion. In particular, swallowing can result in considerable wall motion at the carotid bifurcations, which may induce drastic image degradation or substantial overestimation of wall thickness. Self-gating (SG) techniques have previously been shown to be capable of resolving and compensating for cardiac or respiratory motion during MRI. This work presents an SG-based prospective motion gating scheme that is combined with a 3D variable-flip-angle turbo spin-echo sequence (SPACE) for detecting swallowing motion. SG signal readouts along the superior-inferior direction during each repetition time (TR) period are used to derive the projection profiles of the imaging volume. Based on cross-correlation analysis between the projection profiles and the corresponding reference profiles, swallowing motion can be detected and the motion-contaminated data will subsequently be discarded and reacquired in the next TR. The self-gated SPACE sequence was validated on eight healthy volunteers and two patients and, when compared with the conventional SPACE sequence, proved to be more resistant to swallowing motion and significantly improved image quality as well as the sharpness of carotid artery wall boundaries.

Improved black‐blood imaging using DANTE‐SPACE for simultaneous carotid and intracranial vessel wall evaluation

“…One way to mitigate pulsatile motion is the use of ECG triggering, which should not increase scan time because the TR in the current protocol is similar to a typical RR interval. Navigator (27) or self-gating (28) methods may be adopted in the future. Third, we only designed a T1w protocol in order to reduce the overall exam duration.…”

Quantitative 3D dynamic contrast‐enhanced (DCE) MR imaging of carotid vessel wall by fast T1 mapping using Multitasking

“…Abrupt movement of the subject, such as swallowing, is often inevitable during any scan that spans several minutes . Unaddressed abrupt bulk motion leads to blurring and other motion artifacts.…”

“…Abrupt movement of the subject, such as swallowing, is often inevitable during any scan that spans several minutes. 38 Unaddressed abrupt bulk motion leads to blurring and other motion artifacts. Because the carotid vessel wall is thin, it is especially sensitive to motion artifacts that worsen the partial volume effect, leading to incomplete vessel wall visualization and errors in quantification.…”

Assessment of carotid atherosclerotic disease using three-dimensional cardiovascular magnetic resonance vessel wall imaging: comparison with digital subtraction angiography

“…Recently, a three-dimensional (3D) CMR vessel wall imaging (VWI) technique based on 3D T1 weighted (T1w) Sampling Perfection with Application-optimized Contrast using different flip-angle Evolutions (SPACE) has become technically feasible and gained increasing attention for the diagnosis of atherosclerosis [22][23][24][25][26]. This technique is advantageous over conventional two-dimensional techniques, as it has sufficient BB effects, large spatial coverage, high isotropic resolution and signal-to-noise ratio (SNR), excellent scan efficiency, and remarkable cerebrospinal fluid (CSF) signal attenuation [23,24,27].…”