Program Information
Is It Essential to QA HDR Applicators Annually in Clinic?
H Xu1*, X Yang2 , B Yi1 , (1) University of Maryland School of Medicine, Baltimore, MD, (2) Medstar RadAmerica, Baltimore, MD
Presentations
SU-E-T-528 (Sunday, July 12, 2015) 3:00 PM - 6:00 PM Room: Exhibit Hall
Purpose:There is no rigid prescription recommended for the periodic QA of HDR applicators in terms of what must be done and in what frequency. This study investigates the necessity of an annual QA program for HDR applicators, which was performed at an HDR clinic.
Methods:In this clinic, all HDR applicators and dummy sources used for HDR treatment are tested on an annual basis. 10 different types of gyn applicators were involved including CT-compatible and non-CT compatible tandem &ovoid set, interstitial tandem &ring set, cylinder set Miami set, vaginal applicator set, ring set, Fletcher Williamson set. The annually QA tests for these applicators included (1) visual inspection, (2) mechanical integrity, (3) source positioning accuracy tests using kV imaging, or a combination of (1)-(3). The source positioning accuracy tolerance was 2mm. Over 100 tests were performed on 48 and 61 pieces of applicator components in 2013 and 2014, respectively.
Results: Due to the annual QA, the degraded of applicators or dummy source were ascertained. The degradation either affected the feasibility of source delivery or introduced significant source position errors. The failure rate of the HDR applicator annual QA was 1.6% in 2013 and 2.4% in 2014. Each year, different problems on difference components were detected. The unacceptable applicator components were discarded and replaced by the new orders before affecting any patient treatment. This annual QA takes physicist half to one day to finish depending on his or her experience and expertise.
Conclusion:The annual QA tests are determined as essential in clinic and should include visual inspection, mechanical integrity and source positioning accuracy tests. It is strongly suggested to perform annual HDR applicator QA in clinic to increase the confidence to deliver a safe, accurate and appropriate HDR treatment.
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