Sound Velocity Estimation and Beamform Correction by Simultaneous Multimodality Imaging with Ultrasound and Magnetic Resonance
- Resource Type
- Authors
- Shimpei Arai; Ken Inagaki; Kengo Namekawa; Iwaki Akiyama
- Source
- Applied Sciences, Vol 8, Iss 11, p 2133 (2018)
Applied Sciences
Volume 8
Issue 11
- Subject
- Beamforming
Scanner
subcutaneous fat layer
01 natural sciences
lcsh:Technology
Imaging phantom
030218 nuclear medicine & medical imaging
beamforming
MR-visible fiducial marker
lcsh:Chemistry
03 medical and health sciences
0302 clinical medicine
0103 physical sciences
medicine
signal-to-noise ratio (SNR)
General Materials Science
010301 acoustics
Instrumentation
Image resolution
spatial resolution
lcsh:QH301-705.5
Fluid Flow and Transfer Processes
Physics
medicine.diagnostic_test
business.industry
lcsh:T
Process Chemistry and Technology
Ultrasound
General Engineering
Magnetic resonance imaging
lcsh:QC1-999
Computer Science Applications
Cross section (geometry)
thyroid imaging
lcsh:Biology (General)
lcsh:QD1-999
lcsh:TA1-2040
1-3 piezocomposite material
business
Fiducial marker
lcsh:Engineering (General). Civil engineering (General)
lcsh:Physics
Biomedical engineering
MRI
- Language
- English
- ISSN
- 2076-3417
Since the sound velocity for medical ultrasound imaging is usually set at 1540 m/s, the ultrasound imaging of a patient with a thick layer of subcutaneous fat is degraded due to variations in the sound velocity. This study proposes a method of compensating for image degradation to correct beamforming. This method uses the sound velocity distribution measured in simultaneous ultrasound (US) and magnetic resonance (MR) imaging. Experiments involving simultaneous imaging of an abdominal phantom and a human neck were conducted to evaluate the feasibility of the proposed method using ultrasound imaging equipment and a 1.5 T MRI scanner. MR-visible fiducial markers were attached to an ultrasound probe that was developed for use in an MRI gantry. The sound velocity distribution was calculated based on the MRI cross section, which was estimated as a corresponding cross section of US imaging using the location of fiducial markers in MRI coordinates. The results of the abdominal phantom and neck imaging indicated that the estimated values of sound velocity distribution allowed beamform correction that yielded compensated images. The feasibility of the proposed method was then evaluated in terms of quantitative improvements in the spatial resolution and signal-to-noise ratio.