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Obituary | Edwin L. Carstensen | 1919-2016
Edwin L. Carstensen, Acousti- cal Society of America Fellow, Helmholtz-Rayleigh Interdisci- plinary Silver Medal recipient, and member of the National Academy of Engineering, died at his home in Rochester, NY, on June 24, 2016.
Born and raised in Oakdale, NE, Ed attended Nebraska State Teachers College from 1938 to 1941. His interest in music and physics led him in 1941 to the Case School of Applied Science for graduate studies. He worked under Robert S. Shankland, but when World War II intervened, in 1942 Ed followed Shankland to the Under- water Sound Reference Laboratory (USRL) in Orlando, FL. His pioneering work on sound propagation through bubbly water (Carstensen and Foldy, 1947) stood him in good stead years later when he encountered bubbles in blood and began
studies of cavitation in tissue.
Switching from underwater sound, in 1948 Ed began PhD studies in biophysics at University of Pennsylvania, Phila- delphia. Herman Schwan became his mentor. Schwan intro- duced Ed to tissue biophysics, particularly electromagnetic properties of tissue, and Ed threw acoustics into the mix. The result was another pioneering study on ultrasound absorp- tion in blood, focusing on the role of relaxation (Carstensen and Schwan, 1959). Ed finished his PhD degree in physics in 1955 and spent five years at the Army Biological Laboratory, Fort Detrick, MD, where he worked on the dielectric proper- ties of bacteria. In 1961, Ed joined the faculty of the newly formed Department of Electrical Engineering at the Univer- sity of Rochester (UR), Rochester, NY, where he remained for the rest of his career.
Although his interest in electromagnetic effects in biology continued, in the late 1960s, Ed made a seminal return to acoustics. Using diagnostic ultrasound, Ed’s colleague Ray Gramiak (UR Medical Center) observed strong ultrasound echoes accompanying injection of a radiopaque dye into the heart. Ed and his student Fred Kremkau investigated and de- termined that tiny bubbles produced by the injection caused the echoes (Kremkau et al., 1970). Thus was born ultra-
sound contrast science. A whole slew of influential studies in biomedical acoustics ensued, for example, the discovery of nonlinear acoustics being responsible for the mysterious effects in biomedical ultrasound experiments (Carstensen et al., 1980); the use of intense ultrasound to produce thermal lesions in tumors (a forerunner of high-intensity focused ul- trasound); the effects of ultrasound on the lungs (Child et al., 1990), blood, heart, reproductive organs, kidney, and plants; lithotripsy; and bubblelike lung resonance produced by au- diofrequency sound. Much of the research occurred after Ed formally retired as professor emeritus in 1990. Indeed, he continued productive research for the rest of his life. Shear strain in tissue, his passion during his last decade, was the subject of his last paper (Carstensen et al., 2016), a fit vale- dictory to a life spent uncovering the mysteries of nature.
Ed married Pam McDonald in 1947. Their children, Rich- ard, Allen, Laura, Dee, and Christina, seven grandchildren, and two great-grandchildren survive him.
Selected Articles by Edwin L. Carstensen
Carstensen, E. L., and Foldy, L. L. (1947). Propagation of sound through a liquid containing bubbles. The Journal of the Acoustical Society of America 19, 481-501.
Carstensen, E. L., and Schwan, H. P. (1959). Acoustic properties of hemoglo- bin solutions. The Journal of the Acoustical Society of America 31, 305-311.
Carstensen, E. L., Law, W. K., McKay, N. D., and Muir, T. G. (1980). Dem- onstration of nonlinear acoustical effects at biomedical frequencies and intensities. Ultrasound in Medicine and Biology 6, 359-368.
Carstensen, E. L., Parker, K. J., Dalecki, D., and Hocking, D. C. (2016). Bio- logical effects of low-frequency shear strain: Physical descriptors. Ultra- sound in Medicine and Biology 42, 1-15.
Child, S. Z., Hartman, C. L., Schery, L. A., and Carstensen, E. L. (1990). Lung damage from exposure to pulsed ultrasound. Ultrasound in Medicine and Biology 16, 817-825.
Kremkau, F. W., Gramiak, R., Carstensen, E. L., Shah, P. M., and Kramer, D. H. (1970). Ultrasonic detection of cavitation at catheter tips. American Journal of Roentgenology, Radium Therapy and Nuclear Medicine 110, 177- 183.
Written by:
David T. Blackstock, Email: dtb@austin.utexas.edu
University of Texas at Austin
Kevin J. Parker, Email: kevin.parker@rochester.edu Diane Dalecki, Email: dalecki@bme.rochester.edu
University of Rochester
Winter 2016 | Acoustics Today | 63