TY - JOUR
T1 - Noise Suppression for Ultrasound Attenuation Coefficient Estimation Based on Spectrum Normalization
AU - Gong, Ping
AU - Song, Pengfei
AU - Huang, Chengwu
AU - Lok, U. Wai
AU - Tang, Shanshan
AU - Zhou, Chenyun
AU - Yang, Lulu
AU - Watt, Kymberly D.
AU - Callstrom, Matthew
AU - Chen, Shigao
N1 - Publisher Copyright:
© 1986-2012 IEEE.
PY - 2021/8
Y1 - 2021/8
N2 - Ultrasound attenuation coefficient estimation (ACE) has great diagnostic potential for fatty liver detection and assessment. In a previous study, we proposed a reference phantom-free ACE method, called reference frequency method (RFM), which does not require a calibrated phantom for normalization. The power of each frequency component can be normalized by the power of an adjacent frequency component in the spectrum to cancel system-dependent effects such as focusing and time gain compensation (TGC). RFM demonstrated accurate ACE in both phantom and in in-vivo liver studies. However, our study also showed that the robustness and penetration of RFM were affected by noise in the ACE signals. Here we propose a noise suppression (NS) and a signal-to-noise ratio (SNR) quality control method to reduce the influence of noise on ACE-RFM performance. The proposed methods were tested in harmonic ACE because harmonic imaging is a more frequently used mode than fundamental imaging for abdominal applications. After applying the NS and SNR control methods, the noise-induced bias for attenuation estimation in harmonic ACE was effectively reduced, leading to significantly improved effective penetration depth. The proposed methods directly measure the noise spectrum of the ultrasound system, which can also be adapted to other spectrum-based ACE methods, such as the reference phantom method and the spectra shift method.
AB - Ultrasound attenuation coefficient estimation (ACE) has great diagnostic potential for fatty liver detection and assessment. In a previous study, we proposed a reference phantom-free ACE method, called reference frequency method (RFM), which does not require a calibrated phantom for normalization. The power of each frequency component can be normalized by the power of an adjacent frequency component in the spectrum to cancel system-dependent effects such as focusing and time gain compensation (TGC). RFM demonstrated accurate ACE in both phantom and in in-vivo liver studies. However, our study also showed that the robustness and penetration of RFM were affected by noise in the ACE signals. Here we propose a noise suppression (NS) and a signal-to-noise ratio (SNR) quality control method to reduce the influence of noise on ACE-RFM performance. The proposed methods were tested in harmonic ACE because harmonic imaging is a more frequently used mode than fundamental imaging for abdominal applications. After applying the NS and SNR control methods, the noise-induced bias for attenuation estimation in harmonic ACE was effectively reduced, leading to significantly improved effective penetration depth. The proposed methods directly measure the noise spectrum of the ultrasound system, which can also be adapted to other spectrum-based ACE methods, such as the reference phantom method and the spectra shift method.
KW - Effective penetration depth improvement
KW - frequency power spectra decay
KW - noise suppression (NS)
KW - ultrasound attenuation coefficient estimation (ACE)
UR - http://www.scopus.com/inward/record.url?scp=85104641257&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85104641257&partnerID=8YFLogxK
U2 - 10.1109/TUFFC.2021.3074293
DO - 10.1109/TUFFC.2021.3074293
M3 - Article
C2 - 33877970
AN - SCOPUS:85104641257
SN - 0885-3010
VL - 68
SP - 2667
EP - 2674
JO - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
IS - 8
M1 - 9408614
ER -