Esaote MyLabX75VET, Начало работы

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A D D I T I O N A L I N F O R M A T I O N O N S A F E T Y
MyLab
- G E T T I N G S T A R T E D 2 - 14
Color Doppler should not be utilized except for clearly defined clinical
reasons which provide additional diagnostic or prognostic information.
Women Health
Gynecology - Transvaginal
Examination should be performed with more cautions because heating of the
transducer has the potential to produce additional heat to adjacent tissue.
The ALARA principle should be observed when adjusting controls that affect
the acoustic output and transducer dwell times should be considered.
Gynecology - Shear Wave Elastography
When acoustic radiation force impulses are used, significant temperature rises
may occur, especially, if bones lie in the beam.
Transducer self-heating increases with high number of pulse sequences and
scan duration.
It may not be appropriate or valid to apply the current TI models in the SWE,
since TI is a steady state estimates while the SWE is generated by the ultra-
fast repetitive of short-duration focused acoustic pulses. So far, no specific
risk indicator has been developed, thus the duration of the SWE should be
kept as less as possible to reduce the thermal stress to the targeted tissue.
Fetal
Acoustic output from diagnostic ultrasound devices is sufficient to cause
temperature elevations in fetal tissue. In general, temperature elevations
become progressively greater from B-mode to color Doppler to spectral
Doppler applications.
For identical exposure conditions, the temperature rise near bone increases
with ossification development throughout gestation.
Although, in general, an adverse fetal outcome is possible at any time during
gestation, most severe and detectable effects of thermal exposure in animals
have been observed during the period of organogenesis.
For identical exposure conditions, the potential for thermal bioeffects
increases with the dwell time during examination. Ultrasound exposures that
elevate fetal temperature by 4°C above normal for 5 minutes or more have
the potential to induce severe developmental defects.