Chison SonoEye P2, Руководство пользователя

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Digital Color Doppler Palm Ultrasound System
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this equipment could result in increased electromagnetic emissions or decreased electromagnetic immunity
of this equipment and result in improper operation.
2.5 Biological Safety
This product, as with all diagnostic ultrasound equipment, should be used only for valid reasons and should
be used both for the shortest period of time and at the lowest power settings necessary (ALARA - As Low As
Reasonably Achievable) to produce diagnostically acceptable images. The AIUM offers the following
guidelines:
Clinical Safety Quoted from AIUM
Approved March 26, 1997
Diagnostic ultrasound has been in use since the late 1950s. Given its known benefits
and recognized efficacy for medical diagnosis, including use during human pregnancy,
the American Institute of Ultrasound in Medicine herein addresses the clinical safety of
such use:
There are no confirmed biological effects on patients or instrument operators caused by
exposures from present diagnostic ultrasound instruments. Although the possibility
exists that such biological effects may be identified in the future, current data indicate
that the benefits to patients of the prudent use of diagnostic ultrasound outweigh the
risks, if any that may be present.
Heating :
Elevating tissue temperature during obstetrical examinations creates medical concerns. At the
embryo development stage, the rise in temperature and the length of time exposed to heat combine to
determine potential detrimental effects. Exercise caution particularly during Doppler/Color exams. The
Thermal Index (TI) provides a statistical estimate of the potential temperature elevation (in centigrade) of
tissue temperature. Three forms of TI are available: Soft Tissue Thermal Index ( TIS ), Bone Thermal Index
( TIB ).
Soft Tissue Thermal Index (TIS) . Used when imaging soft tissue only, it provides an estimate of potential
temperature increase in soft tissue.
Bone Thermal Index (TIB). Used when bone is near the focus of the image as in the third trimester OB
examination, it provides an estimate of potential temperature increase in the bone or adjacent soft tissue.
Cavitation:
Cavitation may occur when sound passes through an area that contains a cavity, such as a
gas bubble or air pocket (in the lung or intestine, for example). During the process of cavitation, the sound
wave may cause the bubble to contract or resonate. This oscillation may cause the bubbles to explode and
damage the tissue. The Mechanical Index (MI) has been created to help users accurately evaluate the