Radiation and exposure time in videofluoroscopic swallow studies: A 7-year analysis

Videofluoroscopic swallow studies (VFSSs) are considered the gold standard for evaluating dysphagia. Since the technique involves ionizing radiation, reducing the radiation dose received by pediatric patients must be a priority. This requires the establishment of appropriate diagnostic reference levels.

To evaluate and analyze the radiation dose and exposure time during VFSS in pediatric patients managed in a tertiary care center. Additionally, to determine the relationship between clinical variables and radiation exposure, and to compare the results with the European diagnostic reference levels.

We conducted a retrospective and descriptive study between 2015 and 2022. The dose-area product and fluoroscopy time were analyzed, along with clinical and epidemiological variables and their association with VFSS findings. We also compared the results to the European pediatric imaging diagnostic reference levels (PiDRL) for VFSS.

A total of 322 VFSS were analyzed. Dysphagia was present in 68.6% of cases, and was most commonly oropharyngeal (65%), with combined impairment of swallowing efficiency and safety (61.1%). Dysphagia was more frequent and severe in patients with neurological disorders. Aspiration and/or penetration events were observed in two-thirds of the patients, with approximately 80% being silent (i.e., without cough). The median dose-area product was 9.2 cGy/cm² (IQR, 5.1-15) and the median exposure time was 123 s (IQR, 85-167.3), both values below the thresholds recommended by the 2018 European guidelines and similar studies. We found a direct correlation of both radiation dose and exposure time to age, the degree of disability, the presence of dysphagia, the Bolus Residue Scale (BRS) score, and impairment of swallowing efficiency and safety.

The radiation dose and fluoroscopy time were lower than those reported in previous studies, probably due to technical improvements in the procedure. Establishing updated diagnostic reference levels for pediatric VFSS should be a priority in order to optimize radiation exposure in a population with greater radiosensitivity. This study also aims to contribute to the development of a standardized radiation protocol for pediatric VFSS to allow for more consistent and comparable data across centers.