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Portal Image Rejection Rates in Cross Coverage Situations

R McGurk*, G Tracton, Dept of Radiation Oncology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC


(Tuesday, 7/31/2018) 9:30 AM - 10:00 AM

Room: Exhibit Hall | Forum 9

Purpose: Record and verify (R&V) systems commonly employed in radiation oncology offer a wealth of data that can be accessed to answer a variety of clinically interesting questions. In our clinic, patients receive initial and weekly port films to verify positioning and beam shape. Physicians must review and approve these images for treatment to start and progress. In many cases, the patient's primary physician is not available to review, necessitating another physician to provide cross-coverage. We investigate whether this situation produces different rates of image approval. In addition, treatment site, reviewing physician and length of treatment were also studied to see if these had an influence on rejection rates.

Methods: The clinical MOSAIQ R&V database was queried to extract data from all patients undergoing radiation therapy at the North Carolina Cancer Hospital in calendar years 2013 & 2014. Specifically, all patients that had port films taken during this time were extracted, cleaned, and had their treatment site identified. Image rejection rates as a function of cross-coverage, treatment site, reviewing physician, and length of treatment were calculated. A total of 13,191 images were available for analysis.

Results: Rejection rates were 6.6% and 6.5% for images reviewed by the primary and cross-covering physician, respectively. Rejection rates were lowest for head (4.6%) and highest for spine (8.4%). Physician rejection-rates varied from 1.1% up to 18.1%. As treatment progressed, there was an observed trend with increasing rejection rates from 6% for a second port film encounter up to 10% for the tenth port film encounter.

Conclusion: This was a proof of concept for an internal quality-improvement project undertaken in our clinic. It indicates that port film rejection rates are not influenced by a cross-coverage situation but instead appear to vary more with specific site and reviewing physician, with a possible trend with treatment duration.


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