TY - JOUR
T1 - Superthreshold behavior and threshold estimation of ultrasound-induced lung hemorrhage in adult mice and rats
AU - Zachary, James F.
AU - Sempsrott, Jason M.
AU - Frizzell, Leon A.
AU - Simpson, Douglas G.
AU - O'Brien, William D.
N1 - Funding Information:
Manuscript received March 17, 2000; accepted September 21, 2000. This work was supported by NIH Grant HL58218 awarded to W. D. O’Brien, Jr. and J. F. Zachary and NSF Grant DMS-0073044 awarded to D. G. Simpson. J. F. Zachary is with the Department of Veterinary Pathobiology, University of Illinois, Urbana, IL 61802 (e-mail: [email protected]). J. M. Sempsrott, L. A. Frizzell, and W. D. O’Brien, Jr. are with the Bioacoustics Research Laboratory, Department of Electrical and Computer Engineering, University of Illinois, Urbana, IL 61801. D. G. Simpson is with the Department of Statistics, University of Illinois, Champaign, IL 61820.
PY - 2001/3
Y1 - 2001/3
N2 - Threshold estimates and superthreshold behaviors for ultrasound-induced lung hemorrhage were investigated as a function of species (adult mice and rats) and ultrasound frequency (2.8 and 5.6 MHz). A total of 151 6-to-7-week-old female ICR mice and 160 10-to-11-week-old female Sprague-Dawley rats were randomly divided into two ultrasonic frequency groups, and further randomly divided into seven or eight ultrasonic peak rarefactional pressure groups. Each group consisted of about 10 animals. Animals were exposed to pulsed ultrasound at either 2.8-MHz center frequency (1-kHz PRF, 1.42-μs pulse duration) or 5.6-MHz center frequency (1-kHz PRF, 1.17-μs pulse duration) for a duration of 10 seconds. The in situ (at the pleural surface) peak rarefactional pressure levels ranged between 2.5 and 10.5 MPa for mice and between 2.3 and 11.3 MPa for rats. The mechanical index (MI) ranged between 1.4 and 6.3 at 2.8 MHz for mice and between 1.1 and 3.1 at 5.6 MHz for rats. The lesion surface area and depth were measured for each animal as well as the percentage of animals with lesions per group. The characteristics of the lesions produced in mice and rats were similar to those described in previous studies by our research group and others, suggesting a common pathogenesis in the initiation and propagation of the lesions at the gross and microscopic levels. The percentage of animals with lesions showed no statistical differences between species or between ultrasound frequencies. These findings suggest that mice and rats are similar in sensitivity to ultrasound-induced lung damage and that the occurrence of lung damage is independent of frequency. Lesion depth and surface area also showed no statistically significant differences between ultrasound frequencies for mice and rats. However, there was a significant difference between species for lesion area and a suggestive difference between species for lesion depth. The superthreshold behavior of lesion area and depth showed that rat lung had more damage than mouse lung, and the threshold estimates showed a weak, or lack of, frequency dependency, suggesting that the MI is not consistent with the observed findings.
AB - Threshold estimates and superthreshold behaviors for ultrasound-induced lung hemorrhage were investigated as a function of species (adult mice and rats) and ultrasound frequency (2.8 and 5.6 MHz). A total of 151 6-to-7-week-old female ICR mice and 160 10-to-11-week-old female Sprague-Dawley rats were randomly divided into two ultrasonic frequency groups, and further randomly divided into seven or eight ultrasonic peak rarefactional pressure groups. Each group consisted of about 10 animals. Animals were exposed to pulsed ultrasound at either 2.8-MHz center frequency (1-kHz PRF, 1.42-μs pulse duration) or 5.6-MHz center frequency (1-kHz PRF, 1.17-μs pulse duration) for a duration of 10 seconds. The in situ (at the pleural surface) peak rarefactional pressure levels ranged between 2.5 and 10.5 MPa for mice and between 2.3 and 11.3 MPa for rats. The mechanical index (MI) ranged between 1.4 and 6.3 at 2.8 MHz for mice and between 1.1 and 3.1 at 5.6 MHz for rats. The lesion surface area and depth were measured for each animal as well as the percentage of animals with lesions per group. The characteristics of the lesions produced in mice and rats were similar to those described in previous studies by our research group and others, suggesting a common pathogenesis in the initiation and propagation of the lesions at the gross and microscopic levels. The percentage of animals with lesions showed no statistical differences between species or between ultrasound frequencies. These findings suggest that mice and rats are similar in sensitivity to ultrasound-induced lung damage and that the occurrence of lung damage is independent of frequency. Lesion depth and surface area also showed no statistically significant differences between ultrasound frequencies for mice and rats. However, there was a significant difference between species for lesion area and a suggestive difference between species for lesion depth. The superthreshold behavior of lesion area and depth showed that rat lung had more damage than mouse lung, and the threshold estimates showed a weak, or lack of, frequency dependency, suggesting that the MI is not consistent with the observed findings.
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U2 - 10.1109/58.911741
DO - 10.1109/58.911741
M3 - Article
C2 - 11370372
AN - SCOPUS:0035263395
SN - 0885-3010
VL - 48
SP - 581
EP - 592
JO - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
IS - 2
ER -