Patients' radiation dose during videofluoroscopic swallowing studies according to underlying characteristics.

The videofluoroscopy swallowing study (VFSS) is regarded as the gold standard in diagnosing and assessing swallowing disorders. The goal of this study was to evaluate patients' radiation dose during a VFSS and to determine the influence of patients' underlying characteristics on radiation exposure risk. A total of 295 patients who underwent VFSS were included in this study. The fluoroscopy machine was equipped with a dose area product (DAP). The mean screening time was 4.82 ± 1.80 min and the mean DAP was 9.62 ± 5.01 Gy cm(2). The mean effective dose was 1.23 ± 0.64 mSv. Screening time and DAP had a positive correlation (r = 0.76, P < 0.0001). The cerebrovascular accident (CVA) group showed higher screening time and DAP than the nasopharyngeal cancer (NPC) group with statistical significance. Patients' BMI and DAP had a positive correlation (r = 0.28, P < 0.0001), and height, weight, and body surface area (BSA) also showed positive correlations with DAP. Radiation dose during VFSS is much lower than that of a routine chest CT, and it would take more than 40 VFSSs annually to exceed the annual radiation exposure dose limit according to the mean effective radiation exposure dose of this study. As it is difficult to exceed the annual dose limit, we assume that VFSS is relatively safe in terms of its radiation exposure risk.