Ultrasonic Characterization of Whole Cells and Isolated Nuclei

Taggart, Linda R.; Baddour, Ralph E.; Giles, Anoja; Czarnota, Gregory J.; Kolios, Michael C.

doi:10.1016/j.ultrasmedbio.2006.07.037

« Previous Next »Ultrasound in Medicine and Biology
Volume 33, Issue 3 , Pages 389-401, March 2007

Ultrasonic Characterization of Whole Cells and Isolated Nuclei

Linda R. Taggart
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Ontario Cancer Institute/Princess Margaret Hospital, University Health Network, Toronto, ON, Canada
Ralph E. Baddour
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
Anoja Giles
- Ontario Cancer Institute/Princess Margaret Hospital, University Health Network, Toronto, ON, Canada
Gregory J. Czarnota
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada
- Department of Physics, Ryerson University, Toronto, ON, Canada
- Department of Radiation Oncology, Toronto Sunnybrook Regional Cancer Centre, Toronto, ON, Canada
Michael C. Kolios
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Department of Physics, Ryerson University, Toronto, ON, Canada
- Address correspondence to: Dr. Michael C. Kolios, Ryerson University, Department of Physics, 350 Victoria Street, Toronto, Ontario, Canada, M5B-2K3. http://www.physics.ryerson.ca

Received 17 August 2005; received in revised form 22 July 2006; accepted 27 July 2006. published online 27 January 2007.

Abstract

High frequency ultrasound imaging (20 to 60 MHz) is increasingly being used in small animal imaging, molecular imaging and for the detection of structural changes during cell and tissue death. Ultrasonic tissue characterization techniques were used to measure the speed of sound, attenuation coefficient and integrated backscatter coefficient for (a) acute myeloid leukemia cells and corresponding isolated nuclei, (b) human epithelial kidney cells and corresponding isolated nuclei, (c) multinucleated human epithelial kidney cells and d) human breast cancer cells. The speed of sound for cells varied from 1522 to 1535 m/s, while values for nuclei were lower, ranging from 1493 to 1514 m/s. The attenuation coefficient slopes ranged from 0.0798 to 0.1073 dB mm⁻¹ MHz⁻¹ for cells and 0.0408 to 0.0530 dB mm⁻¹ MHz⁻¹ for nuclei. Integrated backscatter coefficient values for cells and isolated nuclei showed much greater variation and increased from 1.71 × 10⁻⁴ Sr⁻¹ mm⁻¹ for the smallest nuclei to 26.47 × 10⁻⁴ Sr⁻¹ mm⁻¹ for the cells with the largest nuclei. The findings suggest that integrated backscatter coefficient values, but not attenuation or speed of sound, are correlated with the size of the nuclei. (E-mail: mkolios@ryerson.ca)

Key Words: High-frequency ultrasound, Ultrasonic tissue characterization, Isolated nuclei