Hologic Fluoroscan InSight FD Mini C-arm, Руководство пользователя

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InSight FD Mini C-arm User Guide
Radiation Safety
2 MAN-04858 Revision 006
2 Radiation Safety
Improper imaging procedures or the failure to observe radiation safety
and technique factor recommendations could result in increased
exposure. It is the operator's responsibility to observe all safety
procedures and to keep radiation exposures As Low As Reasonably
Achievable (ALARA) and to comply with all national, state and local
regulatory requirements.
Hologic recommends that all members of the operating staff wear a
radiation monitoring device. This is usually a film badge or TLD
(thermoluminescent dosimetry) dosimeter which will record any
radiation dose over a specific period of time. The physician should wear a
ring badge to record any exposure to his/her hands.
2.1 General
A fluoroscopic device emits a continuous beam of X-rays in order to view
an object in real-time.
Primary radiation is present in the space between the X-ray source and the
detector screen. The operator should never place his/her own hands in the
beam.
Secondary radiation or X-ray scatter is caused by X-rays that do not fully
penetrate the object placed in the primary beam. X-ray scatter has
considerably less energy than the primary beam and is absorbed by other
objects in the immediate area. The amount of scatter depends upon the
power setting used, the density and proximity of the body part to the
beam, and the length of exposure time.
2.2 Radiation Dose and Dose Rate
Radiation received by each kilogram of a patient’s body is called dose .
Dose rate refers to the dose received per unit time.
Distance from the X-ray source reduces dose to both the patient and the
operator. For example, at maximum output the dose is 2.6 mGy/minute at
the image receptor and 45 mGy/minute at the Tube Housing exit port, or
17 times greater than what? . This higher value is known as the maximum
Entrance Exposure Rate (EER).
Scattered radiation decreases with the square of the distance in exactly the
same way as noted previously for X-rays in the primary beam. However,
as the dose rate is much less, scatter is usually expressed in mR/hour
(1 mR = 0.01 mGy).
Dose and scatter data for the InSight FD system is available from Hologic
upon request.