Room: Exhibit Hall | Forum 8
Purpose: To (1) quantify organ absorbed doses received by patients undergoing Peripherally Inserted Central Catheter (PICC) and Transjugular Intrahepatic Portosystemic Shunt (TIPS) interventional procedures, and (2) assess the sensitivity of dose to radiation field shape and explicit field positioning using Monte Carlo radiation transport and a library of morphometrically-unique computational human phantoms.
Methods: A website was created allowing a physician to map each irradiation event to a computational phantom matched based on height, weight, age, and gender. With this interface, a physician was able to provide the field dimensions as well as explicitly mapping each radiation event to a location on the computational phantom. Additionally, for each procedure, the radiation dose structure report (RDSR) was utilized to pull information for each exposure. Within the RDSR for each exposure, parameters were pulled such as field area, tube voltage, table position, and dose area product (DAP). This information combined with the localization information provided in the website were used to create a Monte Carlo simulation of the procedure where organ doses were tallied along with a simulated DAP allowing for the reporting of both organ absorbed dose and procedure-cumulative effective dose. Along with explicitly modeling every field, two parameters were modified to assess dose sensitivity. First, a square field was assumed as only field area is provided in the RDSR. Second, only one image was used to localize simulation and the procedure and subsequent exposures were modeled by implicitly shifting source based on changes in table position specified in the RDSR.
Results: Organ and effective doses were computed for 24 patients undergoing PICC and TIPS procedures with the number of exposures ranging from 4-360.
Conclusion: This study presents a method to assess radiation dose for interventional procedures in a scalable and accurate manner allowing accurate dose tracking metrics on an organ level.