YY/T 0642-2014 Ultrasonics—Field characterization—Test methods for the determination of thermal and mechanical indices related to medical diagnostic ultrasonic fields
YY/T 0642-2014 Ultrasonics—Field characterization—Test methods for the determination of thermal and mechanical indices related to medical diagnostic ultrasonic fields
Basic Information
Scope
This standard applies to medical diagnostic ultrasound fields.
This standard specifies:
—— Parameters related to thermal and non-thermal effects in diagnostic ultrasound fields;
—— Methods for determining irradiation parameters related to temperature rise caused by ultrasound absorption in theoretical tissue-equivalent models;
—— Methods for determining irradiation parameters applicable to specific non-thermal effects.
Note 1: In the definition of specific parameters in Chapter 3 of this standard, the International System of Units (according to Appendix I b of Part 2 of the ISO/IEC Guide, Fifth Edition) is used, such as beam area and sound intensity. In practice, it may be more convenient to use decimal multiples or fractions of these units. When using and calculating values, users must combine the decimal prefixes and units. For example, beam area can be expressed in cm2, and sound intensity can be expressed in W/cm2 or mW/cm2.
Note 2: In the following calculations, the range of MI is from 0.25 MHz to 15 MHz, and the range of TI is from 0.5 MHz to 15 MHz.
Note 3: The steady-state estimation of the thermal index is based on the sound output power required to generate a 1℃ tissue temperature rise in a homogeneous tissue that meets the "0.3 dBcm-1MHz-1 attenuation model". It may not be applicable to effective transient temperature rise caused by techniques such as radiation force imaging or the use of pulses or bursts of sufficient duration.