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Improving Patient Setup Through the Reduction of IGRT Rejections for HN Patients

N Yu1*, D LaHurd1, M Tom 1, E Murray1 , N Joshi1 , N Woody 1, S Koyfman1 , P Xia1 , (1) Cleveland Clinic, Cleveland, OH


(Sunday, 7/14/2019)  

Room: ePoster Forums

Purpose: Daily CBCT verification for HN cancer improves the precision of treatment setup while reducing planning margins for normal tissue protection. The review of daily CBCT for conventional fractionation treatments is typically retrospective, prior to next treatment, therefore, IGRT physician review rejection rate (IGRT_RRR) may indicate the quality of patient setup. In this work, we report a process at our institution to control and reduce IGRT_RRR for HN patients.

Methods: In our department, physicians are required to review daily CBCT on the day of acquisition and a report of rejected CBCTs is sent to therapist and physics teams daily. In particular, from Oct. 2016, a dosimetrist, who is specialized in HN planning participated in the patient setup next day if the CBCT was rejected in previous day. We compared the IGRT_RRR since since the establishment of the joint patient setup. Student T test was used for statistical analysis.

Results: The percentage of images reviewed on the day of acquisition maintained at greater than 99.8% in the last 3 years. About 50% of all CBCT rejections were from the HN patients. In the first six months following the initiation of joint setup with IGRT_RRR (10/2016 - 3/2017), 39 of the 3749 CBCTs reviewed for HN patients were rejected. In the last six months (9/2018-2/2019), 21 of the 4413 CBCTs for HN patients were rejected. The IGRT_RRR were significantly reduced (p=0.015).

Conclusion: Timely review of CBCTs allows timely feedback to the therapist group to improve patient setup. Joint patient setup for misaligned patients improves the communication of physicians and therapists. Reviewing CBCT rejection reasons allows for an opportunity to discover trends pertaining to CBCT alignment procedures. Through thorough review we can discover teaching opportunities for common CBCT misalignments and drive improvement.


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