2020/03/15 by Gianmarco Pinton, Pinton, Gianmarco
Engineering · Medicine · #FOS: Physical sciences #Medical Physics (physics.med-ph) #Microwave Imaging and Scattering Analysis #Photoacoustic and Ultrasonic Imaging #Ultrasonics and Acoustic Wave Propagation #Ultrasound Imaging and Elastography #Ultrasound and Hyperthermia Applications
paper · pdf · doi:10.48550/arxiv.2003.06927
openalex publication_date 2020/03/15 · openalex created_date 2022/07/26 · openalex updated_date 2026/07/28
Fullwave simulations are applied to an intercostal imaging scenario to\ndetermine the sources of fundamental and harmonic image degradation with\nrespect to aberration and reverberation. These simulations are based on Part I\nof this two part paper, which established the Fullwave simulation methods to\ngenerate realistic ultrasound images based directly on the first principles of\nwave propagation in the human body. The ultasound images are generated based on\nthe first principles of propagation and reflection and they describe interplay\nbetween distributed aberration and reverberation clutter. Three imaging\nscenarios that would not be realizable in vivo are investigated in silico.\nFirst, the ribs were completely removed and replaced with fat. Then, the ribs\nwere maintained in their anatomically correct configuration to yield a\nreference image. Finally the ribs were placed closer together in elevation. The\npropagation based B-mode images show that of these three scenarios the second,\nanatomically correct configuration, has the best contrast-to-noise ratio. This\nis due to two competing effects. First the ribs effectively apodize the\nfundamental and harmonic beams by 3-5 dB. This effect alone would predict an\nimprovement in image quality. However, the B-mode image quality, measured by\nthe contrast-to-noise ratio degrades by 8%. To explain these changes, it is\nshown that a second effect, multiple reverberation, must be taken into account.\nA point spread function analysis shows that when the ribs are placed closer\ntogether they generate significantly more reverberation clutter (by 2.4 to 2.9\ndB), degrading the image quality even though the beamplot has lower sidelobes.\nIn this intercostal imaging scenario the effects of the ribs on beam shape and\nreverberation are therefore in competition in terms of image quality and there\nis an optimal acoustic window that balances them out.\n