Title :
Transcranial shear-mode ultrasound imaging Characterization of Point Spread Function and assessment of excitation techniques
Author :
Yousefi, Ali ; Hynynen, Kullervo
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Toronto, Toronto, ON
Abstract :
This study presents work on an imaging technique that utilizes shear-wave propagation through the skull. The pulse-echo point spread functions (PSF) were obtained by imaging a point scatterer behind ex vivo human craniums at 1 MHz. Brightness images of the target obtained with either shear-mode or conventional longitudinal-mode transmission in the bone were assessed to quantify distortions to the PSF. The signal-to-noise ratio (SNR) limitations introduced by severe attenuation of shear-waves in the skull were overcome with frequency modulated (FM) coded excitations.
Keywords :
bioacoustics; biomechanics; biomedical ultrasonics; bone; brain; optical transfer function; orthopaedics; ultrasonic propagation; PSF; bone; ex vivo human craniums; excitation techniques; frequency 1 MHz; point scatterer; pulse-echo point spread function; shear-wave attenuation; shear-wave propagation; signal-to-noise ratio; skull; transcranial shear-mode ultrasound imaging; Attenuation; Bones; Brightness; Cranium; Frequency modulation; Humans; Scattering; Signal to noise ratio; Skull; Ultrasonic imaging; Brain; Diagnosis; Imaging; Shear waves;
Conference_Titel :
Ultrasonics Symposium, 2008. IUS 2008. IEEE
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-2428-3
Electronic_ISBN :
978-1-4244-2480-1
DOI :
10.1109/ULTSYM.2008.0329
