Fluoroscopy Time of Radiologist-Monitored Modified Barium Swallow Exams in Oncology: A 3-year Single Institution Retrospective Study

Fluoroscopy time is an important metric for radiation safety, but how it is related to dysphagia severity as graded by Dynamic Grade of Swallowing Toxicity (DIGEST) criteria and other factors in oncology practice is undocumented. We evaluated the fluoroscopy time for the bolus protocol used at the originating institution of the DIGEST method and assessed the relationship between fluoroscopy time and DIGEST grade, exam indication, and additional parameters. Eleven trials, including specified VARIBAR® barium volumes, were included in the standard bolus protocol. Electronic health record (EHR) 2018–2021 databases were sampled in a retrospective STARI-guided DIGEST implementation evaluation for clinically reported DIGEST grades in the EHR and matched to fluoroscopy time. The study sample included 4,162 modified barium swallow (MBS) examinations. Using generalized linear modeling, we tested log-transformed fluoroscopy time associations with Tukey’s adjustment for multiple pairwise comparisons. MBS duration ranged from 0.16 to 11.80 min (Median 2.21, IQR 1.98). Fluoroscopy time was associated with exam indication, cancer diagnosis, setting, and DIGEST grade. Fluoroscopy times increased as the DIGEST severity grade worsened (R² = 0.45, p < .0001). MBS indication was also associated with fluoroscopy time (R² = 0.12, p < .0001), with the shortest times for baseline exams and the longest for excluding leaks (Median1.6 vs. 3.5 min). Median fluoroscopy time was shorter among endocrine and metastatic cancer patients and longer among head and neck cancer patients (2 vs. 3 min, R² = 0.02, p < .0001). Inpatient examinations were longer than outpatient (Median 3.1 vs. 2.2 min, R² = 0.02, p < .0001). The bolus protocol was clinically acceptable within ALARA standards. Clinicians should be mindful of increased fluoroscopy time and optimize exams as clinically indicated in patients with severe dysphagia, leak exclusion, and inpatient studies.