Sonoscape SSI-5500, Руководство пользователя

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SSI-6000/SSI-5800/SSI-5500/SSI-5500BW
Digital Color Doppler Ultrasound System
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.
Examples 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 pro-
duction 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 neg-
ative 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.
1.4.2 Understanding the MI/TI Display
Track-3 follows the Output Display Standard for systems which include fetal Doppler
applications. 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
≤
50mW/cm2, and MI
≤
0.23. Track-3
gives the user the freedom to increase the output acoustic power for a specific
exam, and still limit output acoustic power within the global maximum de-rated
Ispta
≤
720 mW/cm2 under an Output Display Standard.
For any diagnostic ultrasonic systems, Track-3 provides an Output Indices Display
Standard. The diagnostic ultrasound systems and its operator’s manual contain the
information regarding an ALARA (As Low As Reasonably Achievable) education
program for the clinical end-user and the acoustic output indices, MI and TI.
The MI describes the likelihood of cavitation, and the TI offers the predicted maxi-
mum temperature rise in tissue as a result of the diagnostic examination.
In general, a temperature increase of 2.5oC must be present consistently at one
spot for 2 hours to cause fetal abnormalities. Avoiding a local temperature rise
above 1oC should ensure that no thermally induced biologic effect occurs.
P/N: 4701-0061-01B
1-6