Some examples where the MI and TI, respectively, are more or less important are shown in
the following table according to
Particular requirements for the basic safety and essential
performance of ultrasonic medical diagnostic and monitoring equipment, IEC 60601-2-37.
According to the American Institute of Ultrasound in Medicine (AIUM) the MI value should be
below 1.4 in case of scanning on tissues containing gas bodies (e.g. lung). The corresponding
MI value displayed on the Voluson™ console is 0.9. This difference in the MI values is due to
the effects of probe to probe variation as well as the calculation accuracy of the displayed MI
value. Therefore, in case of scanning on tissues containing gas bodies the settings should be
chosen so that the MI value displayed on the Voluson™ console is ≤0.9. The displayed MI
value can be controlled by adjusting the U/S power accordingly.
Note
For lung presets the MI can reach a maximum of 0.9 only.
Predefined modes/settings that fulfill the recommendations of the American Institute of
Ultrasound in Medicine (AIUM) are indicated by the display of the following lung-symbol:
. Once these predefined modes/settings are changed, the lung-symbol disappears – and
the suitability of the modes/settings has to be maintained manually by the user.
Of greater importance
Of less importance
MI –
Mechanical
Index
With contrast agents
In the absence of gas bodies, i.e. most tissue
scanning
Cardiac scanning (lung exposure)
Abdominal scanning (bowel gas)
TI – Thermal
Indices
1st trimester scanning
Fetal skull and spine
Neonatal head
Patient with fever
Poorly perfused tissue
Scanning near ribs or bone: TIb
Well perfused tissue, i.e. liver, spleen
Cardiac scanning
Vascular scanning
2.10.5 Reporting Tables
Acoustic output reporting tables according to the below cited standards are provided in the
Advanced Acoustic Output References
.
Particular requirements for the basic safety and essential performance of ultrasonic medical
diagnostic and monitoring equipment, IEC 60601-2-37 .
Information for Manufacturers Seeking Marketing Clearance of Diagnostic Ultrasound Systems
and transducers, FDA Guidance.
Ultrasonics - Field characterization - Test methods for the determination of thermal and
mechanical indices related to medical diagnostic ultrasonic fields, IEC 62359
Safety
2-20
Voluson™ SWIFT / Voluson SWIFT+ Instructions For Use
5831612-100 Revision 4
Содержание Voluson Swift
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