title: A new method for measuring the speed of sound in rat liver ex vivo using an ultrasound system: correlation of sound speed with fat deposition.
abstract: The speed of sound correlates well with the fat content of the liver. Therefore, non-invasive quantification of sound speed in the liver might be of diagnostic value. Here we describe a new non-invasive method that would be clinically applicable for measurement of sound speed in the liver. Sprague-Dawley rats were divided into two groups: a control group and a fatty liver group prepared by keeping the rats on a choline-deficient diet for 6 wk. The livers were subjected to pathologic and biochemical analysis; the speed of sound through the liver tissue was measured using our proposed method and a pulser-receiver as standard. Our results indicated that use of the proposed method makes it feasible to diagnose fatty liver with good accuracy on the basis of sound speed. This approach would have considerable potential for non-invasive diagnosis of fatty liver and would be a valuable adjunct to conventional liver diagnostic procedures.
authors.affiliation: Department of Pediatrics, Jichi Medical University, Tochigi, Japan. Electronic address: h-kumagai@jichi.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Kumagai
authors.affiliation: Department of Pediatrics, Jichi Medical University, Tochigi, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Yokoyama
authors.affiliation: Imaging Technology Center, R&D Management Headquarters, Fujifilm Corporation, Tokyo, Japan.
authors.forename: Kimito
authors.initials: K
authors.lastname: Katsuyama
authors.affiliation: Imaging Technology Center, R&D Management Headquarters, Fujifilm Corporation, Tokyo, Japan.
authors.forename: Shoji
authors.initials: S
authors.lastname: Hara
authors.affiliation: Imaging Technology Center, R&D Management Headquarters, Fujifilm Corporation, Tokyo, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatrics, Jichi Medical University, Tochigi, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Yamagata
authors.affiliation: Department of Clinical Laboratory Medicine, Jichi Medical University, Tochigi, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Taniguchi
authors.affiliation: Hirota Surgical Pathology Institute, Tochigi, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Hirota
authors.affiliation: Hitachiomiya Saiseikai Hospital, Japan.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Itoh
mesh_terms: D000818:Animals; D002796:Choline Deficiency; D004195:Disease Models, Animal; D005234:Fatty Liver / Q000000981:diagnostic imaging*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography
keywords: Fatty liver; Non-invasive diagnosis; Pulser–receiver; Rat; Speed measurement; Speed of sound; Steatosis; Tissue characterization; Ultrasonics; Ultrasound