MediSono P11 EXP, User Manual

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P11 EXP
Portable Digital Color Doppler Ultrasound System
1-7
MI>0.3 There is a possibility of minor damage to neonatal lung or
intestine. If such exposure is necessary, reduce the exposure time
as much as possible.
MI>0.7 There is a risk of cavitation if an ultrasound contrast agent
containing gas micro-spheres is being used. There is a theoretical
risk of cavitation without the presence of ultrasound contrast
agents. The risk increases with MI values above this threshold.
TI>0.7 The overa l exposure time of an embryo or fetus should be
restricted in accordance with Table 1.1 below as a reference.
TI Maximum exposure time (minutes)
0.7 60
1.0 30
1.5 15
2.0 4
2.5 1
Table 1.1:
Maximum recommended exposure times for an embryo or fetus
11. Non-diagnostic use of ultrasound equipment is not generally recommended. Ex-
amples of non-diagnostic uses of ultrasound equipment include repeated scans for
operator training, equipment demonstration using normal subjects, and the production
of souvenir pictures or videos of a fetus.
For equipment of which the safety indices are displayed over their full range of values,
the TI should always be less than 0.5 and the MI should always be less than 0.3.
Avoid frequent repeated exposure of any subject.
Scans in the first trimester of pregnancy should not be carried out for the sole purpose
of producing souvenir videos or photographs, nor should their production involve
increasing the exposure levels or extending the scan times beyond those needed for
clinical purposes.
12. Diagnostic ultrasound has the potential for both false positive and false negative
results. Misdiagnosis is far more dangerous than any effect that might result from the
ultrasound exposure. Therefore, diagnostic ultrasound should be performed only by
those with sufficient training and education.
1.6.1.1 Temperature Display for Transducers Intended for Internal Use
For transducers intended for internal applications, for example the intracavitary or trans-
esophageal transducers, the transducer tip temperature is displayed on the screen. Refer
to Figure 1.1 for the location of the temperature display. To protect the patient against the
harm of excessive temperature, the system automatically turns off the transducer when the
temperature of the transducer reaches a threshold temperature, which is adjustable and
has a maximum value of 43
◦
C
.
1.6.2 Understanding the MI/TI Display
Track-3 follows the Output Display Standard for systems which include fetal Doppler appli-
cations. The acoustic output will not be evaluated on an application-specific basis, but the
global maximum de-rated Ispta must be
≤
720 mW/cm2 and either the global maximum MI
must be
≤
1.9 or the global maximum de-rated Isppa must be
≤
190 W/cm2. An exception
is for ophthalmic use, in which case the TI=max (TIS_as, TIC) is not to exceed 1.0; Ispta.3