Room: ePoster Forums
Purpose: Due to the increasing use of small animal irradiation machines, there is also an increasing need for guidelines on quality assurance (QA) on such machines. Today, there are some suggestions for simple QA programs, for specific phantoms, and for image quality. The purpose of this work is to present a proposal of a comprehensive and efficient overall quality assurance program on a Small Animal Radiation Research Platform, SARRP (Xstrahl Ltd., Camberley, UK).
Methods: Our QA program accounts for: dosimetry, geometric alignement/accuracy, image quality, treatment planning, and overall accuracy. To effectively cover these aspects we integrated and simplified various checks and procedures in terms of setup and time. For our checks we used a set of phantoms, chambers and other accessories.
Results: On a monthly basis absolute dosimetry should be done. We suggest to perform the following tests on a quarterly basis: pseudo-HVL (half value layer) for treat and image beam, long-time irradiations (20 minutes), isocenter and laser check, and robotics motion check (translation distance / arc). A six months interval is appropriate for a scan of an imaging phantom, light field versus irradiation field check with film (including field size and homogeneity), constancy checks of the treatment planning system (dose calculation for a single field and for an arc), and a test of overall alignment (for example the so-called sandwich test done during regular preventive maintenance). Once a year an arc test for dose and rotation time and an overall end-to-end test should be performed. If equipped with different kinds of collimators (fixed, variable), the relevant checks have to be performed separately for these.
Conclusion: With this comprehensive QA program we think all relevant aspects of the SARRP are addressed. While repeating the checks in the suggested frequency the effort is acceptable.