Siemens SOMATOM Manual page 448

Specials
Radiation exposure to patients
• CARE Vision applies continuous exposure at moder-
ate mA levels.
• Due to the potentially long scan times and the lim-
ited scan volume, the dose for certain slices may
increase to levels significantly higher than those
known from standard CT applications.
• The patient's exposure levels is usually estimated by
CTDIvol.
• This unit is designed to give the average dose in the
scanned volume.
• Before starting the scan, the dose rate (CTDIvol in
mGy per second) is displayed on the monitor.
• During the CARE Vision scan, the accumulated dose
(CTDI vol) reflecting the patient exposure is dis-
played on the monitor. The display scale ranges from
zero to 3000 mGy.
• If the table is shifted during the examination, the
accumulated dose will be distributed to different
slices and will be lower than indicated by the display.
• When a new scan is loaded, the dose display starts
again from zero.
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