title: Characterization of lamina propria and vocal muscle in human vocal fold tissue by ultrasound Nakagami imaging.
abstract: OBJECTIVE
  A number of ultrasound techniques have been applied to identify the biomechanical properties of the vocal folds. These conventional ultrasound methods, however, are not capable of visually mapping the concentration of collagen and elastic fibers in the vocal folds in the form of a parametric image. This study proposes to use a statistical parameter, the Nakagami factor estimated from the statistical distribution of the ultrasonic signals backscattered from tissues, as a means for parametric imaging of the biomechanical properties of the vocal folds.
  
  
  METHODS
  The ultrasonic backscattered signals were acquired from four larynges (eight vocal folds) obtained from individuals without vocal fold pathology for constructing the Nakagami images. The textures of the Nakagami image in the lamina propria (LP) and the vocal muscle (VM) were observed and compared. The average and standard deviation of the Nakagami parameter for the LP and the VM were also calculated.
  
  
  RESULTS
  The results showed that the Nakagami parameter of the LP is larger than that of the VM. Moreover, the LP and the VM have different shading features in the Nakagami images. It was found that the Nakagami parameter may depend on the concentration of collagen and elastic fibers, demonstrating that the Nakagami imaging may allow visual differentiation between the LP and the VM in the vocal folds.
  
  
  CONCLUSIONS
  Current preliminary results suggested that the high-frequency Nakagami imaging may allow real-time visual characterization of the vocal fold tissues in clinical routine examinations.
authors.affiliation: Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan. tsuiph@mail.cgu.edu.tw
authors.forename: Po-Hsiang
authors.initials: PH
authors.lastname: Tsui
authors.forename: Chih-Chung
authors.initials: CC
authors.lastname: Huang
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Seth H
authors.initials: SH
authors.lastname: Dailey
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D006801:Humans; D007821:Laryngeal Muscles / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000000981:diagnostic imaging*; D014463:Ultrasonography; D014827:Vocal Cords / Q000166:cytology / Q000000981:diagnostic imaging*