Isocenter Calibration; Calibrating The Isocenter Position - Brainlab EXACTRAC INFRARED MONITORING Clinical User Manual

4.3

Isocenter Calibration

4.3.1

Calibrating the Isocenter Position

General Isocenter calibration aligns the couch top with the linac isocenter, directly influencing the accuracy
Information of the ExacTrac system.
The determination of the linac's isocenter position is an important and mandatory calibration. This
position is the basis for all ExacTrac calculations. All distances are displayed relative to this point.
By using the isocenter calibration phantom, the point of origin is set with the help of the wall lasers.
From this point, the system knows exactly the geometric alignment of the linac and the patient couch
in relation to the infrared camera system. Thus, it is possible to position patients for treatment with
the highest precision.
Safety Notes Make sure that all markers are screwed onto the ET Isocenter Phantom without a gap between
marker and socket of marker pin.
Clinical User Guide Rev. 1.1, ExacTrac Infrared Monitoring Ver. 1.0
The isocenter position must be verified or calibrated at least once a day. So that the
camera is sufficiently warmed up, ensure that the camera system has been running
for at least 60 minutes before use.
Verify before use that the marker spheres are securely tightened and that the attach-
ment pins are not bent.
Handle the isocenter phantom with care. Accurate calibration cannot be guaranteed if
the phantom or the attached marker spheres are damaged. The marker spheres must
be exchanged at least once a year and immediately if damage occurs.
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