Organ and Detriment-Weighted Dose Estimates within a Large Study on Fluoroscopically Guided Interventional Procedures Performed In the United States
Abstract
Purpose
A multi-institution study is underway to characterize the organ doses received by adult patients undergoing ten common types of fluoroscopically guided interventional (FGI) procedures in the United States. Unlike diagnostic procedures, FGI are not standardized. Patient radiation doses depend on anatomic, lesion, and operator-specific factors. The study will provide an advisory data set that may serve as a reference for typical patient doses. Initial dosimetry efforts within this study focused on transarterial hepatic chemoembolization procedures.
Methods
Radiation dose structured reports (RDSR) were collected from three hospital systems for 276 transarterial hepatic chemoembolization exams. For RDSRs with sufficient exposure parameters, Monte Carlo simulations of the irradiation conditions were generated for each recorded x-ray exposure event. Patient anatomy was modeled using height- and weight-matched computational phantoms from the National Cancer Institute adult phantom library. Absorbed dose estimates were calculated for 31 organs, along with detriment-weighted dose (i.e., the effective dose concept applied to a non-reference male or female).
Results
Of the 276 collected RDSR, 187 RDSR contained sufficient exposure data for dosimetry. Overall, the transarterial hepatic chemoembolization procedure category yielded a median detriment-weighted dose estimate of approximately 40 mSv (range: 2 – 151 mSv). The kidneys demonstrated the highest organ-specific absorbed dose with a median estimate of approximately 200 mGy (range: 15 - 890 mGy).
Conclusion
Organ absorbed and detriment-weighted dose estimates can vary substantially within a given FGI procedure type. By incorporating examination-specific exposure conditions from the RDSR, our dose reconstruction methods enable future studies on the variability of dose estimates by procedure type and the factors associated with higher organ doses. Future work will explore the methods and associated uncertainties for missing exposure variable imputation for those RDSR that were not included in this phase of the study’s dosimetry.