By Topic

Transmission of Ultrasound Through Living Human Thorax

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
H. D. Crawford ; Medico-Technological Res. Dept., St. Barnabas Hospital, Minneapolis, Minn. ; J. J. Wild ; P. I. Wolf ; J. S. Fink

Experiments are described demonstrating the passage of one-mc/sec continuous wave ultrasound through the heart and lungs at power levels of 100 mw/cm2 at the transducer terminals (a total of 1.25 watts). When the sound was directed through the region of the heart, the ultrasound was modulated by the moving intra-thoracic structures in synchronism with the heart beat. The records obtained were modified both by exercise and by amyl nitrite administered to the subject, but remained synchronous with the heart rate. Modulation of the ultrasound did not occur in two warm corpses. Sonic energy at the levels used to traverse the thorax did not affect a simultaneously recorded electrocardiogram. No deleterious effects have been observed on a subject whose heart was irradiated at 1 watt/cm2 and 3 watts/cm2 (totals of 12.5 and 37.5 watts, respectively) applied to transducer terminals at intervals over a period of one year (Appendix I). When continuous wave ultrasound was directed through a lung field clear of the heart, it was found that the attenuation varied 50 db between full inspiration and a lung emptying of 3400 cubic cm (0 db = full inspiration). In addition to direct transmission, sound is scattered throughout the thorax. The mechanics of the ultrasonic phenomena are described.

Published in:

IRE Transactions on Medical Electronics  (Volume:ME-6 ,  Issue: 3 )