SU‐F‐I‐74: Dose Evaluation Based On Monte Carlo Simulation of Three‐Dimensional Rotational Angiography During Hepatic Transarterial Chemoembolization Procedures

Abstract

Purpose:This study was aimed to investigate the dose with patient performing three‐dimensional (3D) angiography imaging during hepatic transarterial chemoembolization (TACE) procedures.Methods:Organ doses and effective doses calculations were retrospectively performed in 88 patients (61 males and 27 females with averaged age of 65.4±12.6 years old) referred for hepatic TACE on a digital flat‐panel angiography system (Bransist safire; Shimadzu) using software (PCXMC; Helsinki, Finland) based on Monte Carlo technique. Patient information (weight and height) and projection data were also used as parameters for dose calculations. Doses were evaluated of the 26 organs in 43 projections at 5° intervals from RAO 120° to LAO 95°. 3D rotational angiography images were acquired three times (before and after contrast, as well as after chemoembolization) using the same exposure techniques (100 kV, 360 mA and 5 ms pulse width) for each patient. Effective doses and dose conversion factors (CFs) were also calculated from the Monte Carlo data.Results:Upper abdominal organs, especially for the dorsal organs, showed the higher dose. Kidney received the highest dose (45.67 mGy) during the whole 3D procedure. Averaged DAP for 88 patients was 394.67±10.85 dGycm2. Averaged effective dose during the 3D procedure were 11.33 mSv. Significant inverse linear relationship was found between effective dose and patient weight (R2 =0.90). Averaged DAP‐to‐effective dose CF were 0.027 mSvdGy−1cm−2 in our study and tend to be decreased as patient weight increased (R2=0.92).Conclusion:Effective dose for the three acquisitions in the 3D rotational angiography of TACE is comparable to the effective dose for one series in the abdominal CT. By utilizing the conversion factors, the DAPs may be useful for estimating the effective dose during 3D abdominal angiographic imaging in the future.