Artifact reduction of susceptibility-weighted imaging using a short-echo phase mask

Ishimori, Yoshiyuki; Monma, Masahiko; Kohno, Yoshihiro

doi:10.3109/02841850903147061

Cited by 7 publications

(5 citation statements)

References 19 publications

(36 reference statements)

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“…On the other hand, since veins have very low signal while arteries still have high signal (provided competent flow rephasing) in SWI processed images, multiplying with the SWI processed magnitude mask may also help suppress the veins in the LS results , and we have also tested this method using the same data we collected (results not shown). For large arteries, masking with SWI images also yielded very high artery‐tissue contrast and negative vein‐tissue contrast.…”

Section: Discussionmentioning

confidence: 99%

Noncontrast‐enhanced magnetic resonance angiography and venography imaging with enhanced angiography

et al. 2013

Magnetic Resonance Imaging

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Section: Discussionmentioning

confidence: 99%

Noncontrast‐enhanced magnetic resonance angiography and venography imaging with enhanced angiography

et al. 2013

Magnetic Resonance Imaging

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“…ESWAN post-processing: All original ESWAN images were sent to Functool 9.4.05a software (GE Healthcare) of Advantage Workstation 4.4 (Sun Microsystems, Santa Clara, CA, USA) for image post-processing. First, image denoising was performed for all original images (the filtration range was expanded to the external edge of the skull), high-pass filtering (64 × 64) was done to eliminate phase distortion caused by field non-homogeneity [ 32 ], and paired phase images and magnetic moment images were obtained after completing calculations and used to determine localization. One slice in the middle, or one slice higher or lower of the bilateral basal ganglia was selected to draw the ROIs, including the caudate nucleus (CA), globus pallidus (GP), putamen (PU), and thalamus (TH) ( Figure 2 ).…”

Section: Methodsmentioning

confidence: 99%

Correlation of iron deposition and change of gliocyte metabolism in the basal ganglia region evaluated using magnetic resonance imaging techniques: an in vivo study

Liu¹,

Wang²

2016

aoms

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IntroductionWe assessed the correlation between iron deposition and the change of gliocyte metabolism in healthy subjects’ basal ganglia region, by using 3D-enhanced susceptibility weighted angiography (ESWAN) and proton magnetic resonance spectroscopy (1H-MRS).Material and methodsSeventy-seven healthy volunteers (39 female and 38 male subjects; age range: 24–82 years old) were enrolled in the experiment including ESWAN and proton MRS sequences, consent for which was provided by themselves or their guardians. For each subject, the mean phase value gained by ESWAN was used to evaluate the iron deposition; choline/creatine (Cho/Cr) and mI/Cr ratios gained by 1H-MRS were used to evaluate gliocyte metabolism in the basal ganglia region of both sides. The paired t test was used to test the difference between the two sides of the basal ganglia region. Linear regression was performed to evaluate the relation between mean phase value and age. Pearson's correlation coefficient was calculated to analyze the relationship between the result of ESWAN and 1H-MRS.ResultsThere was no difference between the two sides of the basal ganglia region in the mean phase value and Cho/Cr. But in mI/Cr the mean phase value of each nucleus in bilateral basal ganglia decreased with increasing age. There are 16 r-values between the mean phase value and Cho/Cr and mI/Cr in bilateral basal ganglia region. And each of all p-values is less than 0.001 (p < 0.001).ConclusionsIron deposition in the bilateral basal ganglia is associated with the change of gliocyte metabolism with increasing age. Iron deposition in each nucleus of the basal ganglia region changes with age.

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“…Magnitude images reflect the overall MR signal, and their corresponding phase image contains information about field inhomogeneity, differences in local precession frequencies, and motion [ 141 ]. Phase images were largely discarded before the implementation of SWI as they require complex unwrapping, referring to the extraction of their original numerical range, which is constrained in the outputted image to [−π, +π] [ 142 ]. However, phase can be used to visualize information that would otherwise be barely visible in magnitude images.…”

Section: Sequence Types and Contrastsmentioning

confidence: 99%

“…Small structures result in field variations with high spatial frequencies, which can be used to enhance contrast by applying a high pass filter. The resulting SWI image is the product of multiplying the phase mask with the magnitude image [ 142 , 143 , 144 ]. It remains somewhat controversial to what extent SWI signal increases from 1.5 T to 3 T MRI.…”

Section: Sequence Types and Contrastsmentioning

confidence: 99%

Methodological Considerations for Neuroimaging in Deep Brain Stimulation of the Subthalamic Nucleus in Parkinson’s Disease Patients

Isaacs

Keuken

Alkemade

et al. 2020

JCM

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Deep brain stimulation (DBS) of the subthalamic nucleus is a neurosurgical intervention for Parkinson’s disease patients who no longer appropriately respond to drug treatments. A small fraction of patients will fail to respond to DBS, develop psychiatric and cognitive side-effects, or incur surgery-related complications such as infections and hemorrhagic events. In these cases, DBS may require recalibration, reimplantation, or removal. These negative responses to treatment can partly be attributed to suboptimal pre-operative planning procedures via direct targeting through low-field and low-resolution magnetic resonance imaging (MRI). One solution for increasing the success and efficacy of DBS is to optimize preoperative planning procedures via sophisticated neuroimaging techniques such as high-resolution MRI and higher field strengths to improve visualization of DBS targets and vasculature. We discuss targeting approaches, MRI acquisition, parameters, and post-acquisition analyses. Additionally, we highlight a number of approaches including the use of ultra-high field (UHF) MRI to overcome limitations of standard settings. There is a trade-off between spatial resolution, motion artifacts, and acquisition time, which could potentially be dissolved through the use of UHF-MRI. Image registration, correction, and post-processing techniques may require combined expertise of traditional radiologists, clinicians, and fundamental researchers. The optimization of pre-operative planning with MRI can therefore be best achieved through direct collaboration between researchers and clinicians.

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Artifact reduction of susceptibility-weighted imaging using a short-echo phase mask

Abstract: Use of a short-echo phase mask in SWI is useful for reducing artifacts.

Cited by 7 publications

References 19 publications

Noncontrast‐enhanced magnetic resonance angiography and venography imaging with enhanced angiography

Noncontrast‐enhanced magnetic resonance angiography and venography imaging with enhanced angiography

Correlation of iron deposition and change of gliocyte metabolism in the basal ganglia region evaluated using magnetic resonance imaging techniques: an in vivo study

Methodological Considerations for Neuroimaging in Deep Brain Stimulation of the Subthalamic Nucleus in Parkinson’s Disease Patients

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