Clinical benchmarking of a commercial software for skin dose estimation in cardiac, abdominal, and neurology interventional procedures.

BACKGROUND: Radiation exposure from interventional radiology (IR) could lead to potential risk of skin injury in patients. Several dose monitoring software like radiation dose monitor (RDM) were developed to estimate the patient skin dose (PSD) distribution in IR. PURPOSE: This study benchmarked the accuracy of RDM software in estimating PSD as compared to GafChromic film baseline in-vivo measurements on patients during cardiac, abdominal, and neurology IR procedures. METHODS: The prospective study conducted in four IR departments included 81 IR procedures (25 cardiac, 31 abdominal, and 25 neurology procedures) on three angiographic systems. PSD and field geometry were measured by placing GafChromic film under the patient's back. Statistical analyses were performed to compare the software estimation and film measurement results in terms of PSD and geometric accuracy. RESULTS: Median values of measured/calculated PSD were 1140/1005, 591/655.9, and 538/409.7 mGy for neurology, cardiac, and abdominal procedures, respectively. For all angiographic systems, the median (InterQuartile Range, IQR) difference between calculated and measured PSD was -10.2% (-21.8%-5.7%) for neurology, -4.5% (-19.5%-15.5%) for cardiac, and -21.9% (-38.7%--3.6%) for abdominal IR procedures. These differences were not significant for all procedures (p > 0.05). Discrepancies increased up to -82% in lower dose regions where the measurement uncertainties are higher. Regarding the geometric accuracy, RDM correctly reproduced the skin dose map and estimated PSD area dimensions closely matched those registered on films with a median (IQR) difference of 0 cm (-1-0.8 cm). CONCLUSIONS: RDM is proved to be a useful solution for the estimation of PSD and skin dose distribution during abdominal, cardiac and neurology IR procedures despite a geometry phantom which is not specific to the latter type of IR procedures.

Benchmarking the DACS-integrated Radiation Dose Monitor® skin dose mapping software using XR-RV3 Gafchromic® films.

PURPOSE: To perform a benchmark of a new DACS-integrated patient skin dose mapping solution using on-phantom measurements with Gafchromic® films. MATERIALS AND METHODS: To calculate cumulative patient skin dose distribution with 1-cm2 resolution, a Radiation Dose Monitor (RDM, Medsquare), using the Radiation Dose Structured Report (RDSR), tabulated backscatter and mass energy absorption coefficients together with site-specific corrections for table, mattress attenuation, and air kerma calibration factor. Peak skin dose (PSD) and two-dimensional (2D) skin dose distributions calculated with RDM were compared against on-phantom measurements with XR-RV3 Gafchromic® films considering two widely used x-ray equipment. Seventeen different settings which include simple and multiple beam projections with extreme angulations (up to 75°), all available fields-of-view (FOVs 48-11 cm), additional collimation, variable table height and lateral positions, and variable phantom thickness (12, 20, and 30 cm) were involved. RESULTS: Due to a careful calibration of films using clinical beam qualities, 22.8% (k = 2) overall measurement uncertainty was achieved. Calculated and measured PSD values agreed with an average difference of 10% ± 7% and 9% ± 7% for 34 test conditions performed on Siemens Artis Zee and GEMS Innova IGS interventional systems, respectively. Finally, RDM's 2D skin dose maps closely matched those registered on XR-RV3 films considering the 1-cm2 resolution. While RDM correctly reproduced beam overlapping due to variable tube projections, FOV, table positions, etc., few challenges were identified related to conversion of rectangular fields to square areas in the RDSR and a stair-step effect visible for large tube projections (>45°). CONCLUSION: The accuracy of RDM's DACS-integrated skin dose mapping software was acceptable considering measurement uncertainties associated with Gafchromic® films.