title: Effects of fatty infiltration in human livers on the backscattered statistics of ultrasound imaging.
abstract: Ultrasound imaging has been widely applied to screen fatty liver disease. Fatty liver disease is a condition where large vacuoles of triglyceride fat accumulate in liver cells, thereby altering the arrangement of scatterers and the corresponding backscattered statistics. In this study, we used ultrasound Nakagami imaging to explore the effects of fatty infiltration in human livers on the statistical distribution of backscattered signals. A total of 107 patients volunteered to participate in the experiments. The livers were scanned using a clinical ultrasound scanner to obtain the raw backscattered signals for ultrasound B-mode and Nakagami imaging. Clinical scores of fatty liver disease for each patient were determined according to a well-accepted sonographic scoring system. The results showed that the Nakagami image can visualize the local backscattering properties of liver tissues. The Nakagami parameter increased from 0.62 ± 0.11 to 1.02 ± 0.07 as the fatty liver disease stage increased from normal to severe, indicating that the backscattered statistics vary from pre-Rayleigh to Rayleigh distributions. A significant positive correlation (correlation coefficient ρ = 0.84; probability value (p value) < 0.0001) exists between the degree of fatty infiltration and the Nakagami parameter, suggesting that ultrasound Nakagami imaging has potentials in future applications in fatty liver disease diagnosis.
authors.affiliation: Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan City, Taiwan Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.
authors.forename: Yung-Liang
authors.initials: YL
authors.lastname: Wan
authors.affiliation: Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital, Linkou, Chang Gung University, Taoyuan City, Taiwan.
authors.forename: Dar-In
authors.initials: DI
authors.lastname: Tai
authors.affiliation: Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.
authors.forename: Hsiang-Yang
authors.initials: HY
authors.lastname: Ma
authors.affiliation: Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.
authors.forename: Bing-Hao
authors.initials: BH
authors.lastname: Chiang
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Linkou, Chang Gung University, Taoyuan City, Taiwan.
authors.forename: Chin-Kuo
authors.initials: CK
authors.lastname: Chen
authors.affiliation: Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan City, Taiwan Medical Imaging Research Center, Institute for Radiological Research, Chang Gung Memorial Hospital, Linkou, Chang Gung University, Taoyuan City, Taiwan tsuiph@mail.cgu.edu.tw.
authors.forename: Po-Hsiang
authors.initials: PH
authors.lastname: Tsui
mesh_terms: D000368:Aged; D005234:Fatty Liver / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008099:Liver / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography
keywords: Ultrasound Nakagami imaging; envelope statistics; fatty liver