Two novel applications of ultrasonic waves to tissue characterization are described in this proposal: 1) In the first, high frequency acoustic waves scatter off in vitro biological cells in suspension as they are individually convected through the focal zones of confocally positioned transducer. When scattering data are combined with data on the cell volume, obtained from an in-line, electrozone sensing element, one can in principle deduce the volume, compressibility, and density of each cell, and thus determining information on the distribution of properties for a heterogeneous cell population. This mechanical characterization of cell properties may offer new dimensions by which to detect and/or assess disease state or pathologies, and may be adaptable to cell sorting or usable in conjunction with laser cell flow cytometry apparatus for more complete cell characterization. 2) In the second application, new, precise experimental data on the nonlinear parameter of materials now offer the possibility of determining the composition of tissues. Initial tests of a new theoretical methodology suggest that percentages of water, protein, and fat in tissue samples can be determined from ultrasonic measurements. In performing precise ultrasonic measurements and testing (and, where appropriate, modifying) the theory, points of contact will be sought with a) the extensive data base on the acoustic absorption in tissues, protein solutions, and lipid suspensions and b) the recent results of those groups seeking to use the nonlinear acoustic property as an imaging parameter. In the latter case, if spatial information obtained from imaging could be combined with the tissue composition methodology, in vivo spatial information on tissue composition might be possible. The proposed work points in the direction of this important goal.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM030419-08
Application #
3278187
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1982-05-01
Project End
1991-08-31
Budget Start
1989-09-01
Budget End
1990-08-31
Support Year
8
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Yale University
Department
Type
Schools of Arts and Sciences
DUNS #
082359691
City
New Haven
State
CT
Country
United States
Zip Code
06520
Chen, X; Apfel, R E (1997) Radiation force on a spherical object in the field of a focused cylindrical transducer. J Acoust Soc Am 101:2443-7
Chen, X; Apfel, R E (1996) Radiation force on a spherical object in an axisymmetric wave field and its application to the calibration of high-frequency transducers. J Acoust Soc Am 99:713-24
Everbach, E C; Apfel, R E (1995) An interferometric technique for B/A measurement. J Acoust Soc Am 98:3428-38
Jiang, P; Apfel, R E (1994) Method for determining the reliable prediction(s) of compositions of tissue phantoms. Ultrasound Med Biol 20:791-802
Jiang, P; Everbach, E C; Apfel, R E (1991) Applications of mixture laws for predicting the compositions of tissue phantoms. Ultrasound Med Biol 17:829-38
Roy, R A; Apfel, R E (1990) Mechanical characterization of microparticles by scattered ultrasound. J Acoust Soc Am 87:2332-41
Roos, M S (1988) A technique for the study of acoustic scattering from microparticles. J Acoust Soc Am 83:770-6
Roos, M S; Apfel, R E; Wardlaw, S C (1988) Application of 30-MHz acoustic scattering to the study of human red blood cells. J Acoust Soc Am 83:1639-44
Zhu, Z M; Apfel, R E (1985) Shape oscillations of microparticles on an optical microscope stage. J Acoust Soc Am 78:1796-8