Table of Contents
Advertisement
Related Guidance
For more information about ultrasonic bioeffects and related topics, see the following:
"Bioeffects and Safety of Diagnostic Ultrasound." AIUM Report, January 28, 1993.
•
"American Institute of Ultrasound in Medicine Bioeffects Consensus Report."
•
Journal of Ultrasound in Medicine, Vol. 27, Issue 4, April 2008.
Acoustic Output Measurement Standard for Diagnostic Ultrasound Equipment.
•
(AIUM, NEMA, 2004)
Third Edition of the AIUM Medical Ultrasound Safety brochure, 2014. (A copy of
•
this document is provided with each system.)
Information for Manufacturers Seeking Marketing Clearance of Diagnostic
•
Ultrasound Systems and Transducers. FDA, September 2008.
Standard for Real‑Time Display of Thermal and Mechanical Acoustic Output
•
Indices on Diagnostic Ultrasound Equipment. (AIUM, NEMA, 2004)
WFUMB. "Symposium on Safety of Ultrasound in Medicine: Conclusions and
•
Recommendations on Thermal and Non‑Thermal Mechanisms for Biological
Effects of Ultrasound." Ultrasound in Medicine and Biology, 1998: Vol. 24,
Supplement 1.
Acoustics
The system limits patient contact temperature to 43°C (109°F), and acoustic output
values to their respective U.S. Food and Drug Administration limits. A power-protection
circuit protects against over-current conditions. If the power monitor protection circuit
senses an over-current condition, then the drive voltage to the transducer is shut off
immediately, preventing overheating of the transducer surface and limiting acoustic
output. Validation of the power protection circuit is done under normal system
operation.
Acoustic Output and Measurement
Since the initial use of diagnostic ultrasound, the possible human bioeffects from
ultrasound exposure have been studied by various scientific and medical institutions.
corresponding pulse repetition frequency and maximum intensity
point. In combined or simultaneous modes, the TI is the sum of the
contribution from the modes enabled, and the displayed MI is the
largest of the MI values associated with each mode and focal zone
enabled. The system will return to the previously selected state if a
mode is turned off and then reselected.
Transducer: Each transducer type has unique specifications for contact
•
area, beam shape, and center frequency. Defaults are initialized when
you select a transducer. Factory defaults vary with transducer,
application, and selected mode. Defaults have been chosen below the
Intended use.
Documents
P34
Advertisement
Table of Contents
