PTW DIAMENTOR E2, Руководство пользователя

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DIAMENTOR E2
Calibration
D651.131.00/05 en 21
−
Note down the reading M
Reference
shown on the
diagnostic dosemeter.
−
Note down the dose area product reading
shown on the DIAMENTOR E2 (DAP
Measured
).
−
Calculate the dose area product
DAP
Calc
= M
Reference
x A where A is the field size.
−
Repeat the measurement 3 times, noting down
the results.
Fluoroscopy (undercouch tube)
−
Place the measurement phantom without de-
tector on the patient couch (phantom at the bot-
tom).
−
Start fluoroscopy and determine the field size A
in the plane of the phantom by means of the
phantom depicted on the screen.
−
Turn the measurement stand and put the detec-
tor and its holder in place (phantom at the top,
detector at the bottom).
−
Start another fluoroscopy for approx.
30 seconds.
−
Note down the reading M
Reference
shown on the
diagnostic dosemeter.
−
Note down the dose area product reading
shown on the DIAMENTOR E2 (DAP
Measured
).
−
Calculate the dose area product
DAP
Calc
= M
Reference
x A where A is the field size.
−
Repeat the measurement 3 times, noting down
the results.
Fluoroscopy (overcouch tube)
−
Place the measurement stand without detector
on the patient couch (phantom at the top).
−
Start the fluoroscopy and determine the field
size in the plane of the phantom by means of
the phantom depicted on the screen.
−
Turn the measurement stand and put the detec-
tor and its holder in place (phantom at the bot-
tom, detector at the top).
−
Start another fluoroscopy for approx.
30 seconds.
−
Note down the reading M
Reference
shown on the
diagnostic dosemeter.
−
Note down the dose area product reading
shown on the DIAMENTOR E2 (DAP
Measured
).
−
Calculate the dose area product
DAP
Calc
= M
Reference
x A where A is the field size.
−
Repeat the measurement 3 times, noting down
the results.
Calculating the New Chamber Calibration Factor
−
Calculate the mean value of (dose area prod-
uct) DAP
Calc.
−
Calculate the mean value of (dose area prod-
uct) DAP
Measured.
−
Calculate the new chamber calibration factor
K
new
, using the mean values and the old cham-
ber calibration factor:
K
new
=
old
Measured
Calc
K
DAP
DAP
⋅
Saving the New Chamber Calibration Factor
Enter the new chamber calibration factor as de-
scribed in section 4.5.