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residual chemicals or gases could not only result in damage to the accessories but also can
beharmful to human bodies.
You should use the legally marketed rubber latex (probe sheath) when performing trans-esophagus or
intracavitary exam, or biopsy exam. Please check the ingredient of the rubber latex on the
package before purchasing the rubber latex. Contact with natural rubber latex may cause a severe
anaphylactic reaction in persons sensitive to the natural latex protein. Refer to package labeling to check
latex content and FDA
’
s March 29,1991 Medical Alert on latex products
Do not use the footswitch in the operating room.
Only the trained physicians or sonographers can handle the biopsy needle guides under ultrasound guidance.
During the operation, the operator must observe proper needle insertion sequencing with the needle
guide in order to avoid undue discomforts, unnecessary risks or injuries to patient.
You should use the legally marketed medical ultrasound couplants. Please check the user instruction carefully
before using it, please manage and use the ultrasound couplants correctly to prevent it being polluted.
Disconnect the probe from the system after freezing an image or powering off the system.
Otherwise, the system or the probe could be damaged.
1.2 Principles of Using Acoustic Power
Perform ultrasound procedures prudently under the guidance of the ALARA (as low as reasonably
achievable) principle. Expose the patient to the lowest practical transmit power levels in the
shortest possible period to achieve a satisfactory diagnosis.
The operator should notice the effect of the heat on the patient body when the exam is performed around
the bones and the nearby soft tissues which can transform the ultrasound energy to heat energy.
Take special care to the fetal whose bones are growing.
1.2.1 Biological Safety
Diagnostic ultrasound is recognized as being safe, but the risk of biological effects exists when using it in high
exposure levels and long exposure times. Thus ultrasound should be used in a prudent manner to
provide medical benefit to the patient.
1.2.2 Mechanical and Thermal Indices
The ultrasound system displays two parts: thermal Index (TI) and Mechanical Index (MI). The MI/
TI value of the machine is real time displayed at the upper right corner, regarding how to change TI
display type, please choose: Preset → [System Preset] → [TI].
Meaning of MI/TI
Mechanical bioeffects are threshold phenomena that occur when a certain level of output is exceeded.
The threshold level varies with tissue type. The potential mechanical bioeffects varies with peak pressure
and ultrasound frequency. The higher the MI value, the greater the likelihood of mechanical bioeffects
occurring. There is no specific MI value theat means that amechanical effect is actually occurring. The MI
should be used as guide for implementing the ALARA principle.
The TI value informs the operator about the conditions that might lead to an increase in temperature at