User manual

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3. Expose the phantom/film to the chosen radiotherapy treatment plan and note the
time. Remove the application film from the phantom. Keep it where it is not
exposed to light.
4. Choose a calibration film strip from the same production lot as the application
film. Place it in the phantom with the center of the strip close to the center of the
exposure area. Fix the film with adhesive tape and place phantom material above
the film as required.
5. Expose the strip to a known dose between 10% and 30% greater than the
highest dose expected on the application film. One way is to expose a 10 cm x
10 cm open field, but the choice is up to the user with the goal of creating a large
area of uniform exposure on the film. The time window within which the
calibration strip and application film are exposed is related to the speed with
which the dose measurement and comparison to plan can be completed. Your
efficiency increases by minimizing the time window. If the exposures are t min.
apart, film scanning can be done 4t min. later, or any time thereafter. An
explanation is given in the Appendix C. Remove the calibration film from the
phantom. Keep it where it is not exposed to light.
6. Turn on the scanner, connect a computer and open FilmQA
™
Pro. From the
drop-down menu (Fig. 1) under “Case Object Management” select “Open Case
Object from File”. Go to the folder containing the file with the relevant fixed
calibration object , e.g. XXXXXXX.CaseObj, and open the file (assuming the
primary calibration has been done for the production lot of film using FilmQA
™
Pro and the data have been saved as a Calibration Object).