TY - GEN
T1 - Optimizing frequency and pulse shape for ultrasound current source density imaging
AU - Qin, Yexian
AU - Wang, Zhaohui
AU - Ingram, Pier
AU - Li, Qian
AU - Witte, Russell S.
PY - 2011
Y1 - 2011
N2 - Electric field mapping is commonly used to identify irregular conduction pathways in the heart (e.g., arrhythmia) and brain (e.g., epilepsy). A new technique, ultrasound current source density imaging (UCSDI) based on the acoustoelectric (AE) effect, provides an alternative method for current activity mapping in four-dimension with high resolution. The ultrasound transducer frequency and pulse shape significantly affect the sensitivity and spatial resolution of UCSDI. In this paper, we analyze the tradeoff between spatial resolution and sensitivity in UCSDI from two aspects: (1) ultrasound transducer frequency and (2) coded excitation pulses. For frequency dependence, we imaged an electric dipole using ultrasound transducers with different center frequencies (1 MHz and 2.25 MHz) and compared the sensitivity and resolution. For coded excitation, we measured AE signals with chirp excitation at 1 MHz and demonstrated improved sensitivity for chirps (3.5 μV/mA at 1 MHz) compared with square pulse excitation (1.6 μV/mA). Pulse compression was also applied to preserve spatial resolution, demonstrating enhanced detection while preserving spatial resolution.
AB - Electric field mapping is commonly used to identify irregular conduction pathways in the heart (e.g., arrhythmia) and brain (e.g., epilepsy). A new technique, ultrasound current source density imaging (UCSDI) based on the acoustoelectric (AE) effect, provides an alternative method for current activity mapping in four-dimension with high resolution. The ultrasound transducer frequency and pulse shape significantly affect the sensitivity and spatial resolution of UCSDI. In this paper, we analyze the tradeoff between spatial resolution and sensitivity in UCSDI from two aspects: (1) ultrasound transducer frequency and (2) coded excitation pulses. For frequency dependence, we imaged an electric dipole using ultrasound transducers with different center frequencies (1 MHz and 2.25 MHz) and compared the sensitivity and resolution. For coded excitation, we measured AE signals with chirp excitation at 1 MHz and demonstrated improved sensitivity for chirps (3.5 μV/mA at 1 MHz) compared with square pulse excitation (1.6 μV/mA). Pulse compression was also applied to preserve spatial resolution, demonstrating enhanced detection while preserving spatial resolution.
KW - ECG
KW - acoustoelectric
KW - cardiac arrhythmia mapping
KW - coded excitation chirps
UR - http://www.scopus.com/inward/record.url?scp=84869037791&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84869037791&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2011.0530
DO - 10.1109/ULTSYM.2011.0530
M3 - Conference contribution
AN - SCOPUS:84869037791
SN - 9781457712531
T3 - IEEE International Ultrasonics Symposium, IUS
SP - 2138
EP - 2141
BT - 2011 IEEE International Ultrasonics Symposium, IUS 2011
T2 - 2011 IEEE International Ultrasonics Symposium, IUS 2011
Y2 - 18 October 2011 through 21 October 2011
ER -