High-Resolution Magnetic Resonance Imaging Using Compressed Sensing for Intracranial and Extracranial Arteries: Comparison with Conventional Parallel Imaging

Abstract

Objective To compare conventional sensitivity encoding (SENSE) to compressed sensing plus SENSE (CS) for high-resolution magnetic resonance imaging (HR-MRI) of intracranial and extracranial arteries. Materials and Methods HR-MRI was performed in 14 healthy volunteers. Three-dimensional T1-weighted imaging (T1WI) and proton density-weighted imaging (PD) were acquired using CS or SENSE under the same total acceleration factors (AF t )-5.5, 6.8, and 9.7 for T1WI and 3.2, 4.0, and 5.8 for PD-to achieve reduced scanning times in comparison with the original imaging sequence (SENSE T1WI, AF t 3.5; SENSE PD, AF t 2.0) using the 3-tesla system. Two neuroradiologists measured signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and used visual scoring systems to assess image quality. Acceptable imaging was defined as a visual score ≥ 2. Repeated measures analysis of variance and Cochran's Q test were performed. Results CS yielded better image quality and vessel delineation than SENSE in T1WI with AF t of 5.5, 6.8, and 9.7, and in PD with AF t of 5.8 ( p < 0.05). CS T1WI with AF t of 5.5 and CS PD with AF t of 3.2 and 4.0 did not differ significantly from original imaging ( p > 0.05). SNR and CNR in CS were higher than they were in SENSE, but lower than they were in the original images ( p < 0.05). CS yielded higher proportions of acceptable imaging than SENSE (CS T1WI with AF t of 6.8 and PD with AF t of 5.8; p < 0.0167). Conclusion CS is superior to SENSE, and may be a reliable acceleration method for vessel HR-MRI using AF t of 5.5 for T1WI, and 3.2 and 4.0 for PD.

Contrast-Enhanced High-Resolution Intracranial Vessel Wall MRI with Compressed Sensing: Comparison with Conventional T1 Volumetric Isotropic Turbo Spin Echo Acquisition Sequence

“…CS also provided robust and repeatable results with an acceleration factor of 1.5 (15). Further, CS with an acceleration factor of 3-5 applied to intracranial VW-MRIs yielded higher or comparable image quality to marked time reductions (13,14). Here, we used an extra reduction factor of 1.5 in VISTA-CS, which did not significantly affect image quality.…”

“…Several prior studies reported that CS achieved substantial scan time reduction while providing similar or superior SNR, CNR, VW delineation, and image quality in intracranial VW-MRIs (13,14). Those studies enrolled mostly healthy volunteers; therefore, validation in large patient cohorts was necessary to use CS in clinical practice.…”

“…Most previous studies of VW-MRIs adopted CS in order to reduce scan acquisition time. CS reduced the scan time without significantly sacrificing image quality in both intra- and extracranial VW-MRIs ( 12 13 14 ), while also providing robust and reproducible images ( 15 ). Most of the study subjects, however, were healthy volunteers and the clinical usefulness of CS in intracranial VW-MRIs must be validated in a large patient cohort.…”

Deep-learning-based image quality enhancement of compressed sensing magnetic resonance imaging of vessel wall: comparison of self-supervised and unsupervised approaches

“…The research was performed in accordance with relevant guidelines and regulations. The study population and image acquisitions were as previously described 9 .…”

“…However, loss of image quality, as compared with a fully sampled MRI, is unavoidable. A previous study 9 reported that CS HRPD MR images with high acceleration factors yields unacceptable imaging for radiological reading. As low-quality vessel wall imaging hampers accurate diagnosis 9 – 11 , improving the image quality of CS HRPD MR images would be beneficial for accurate radiological reading and diagnosis.…”