M. Alvarez et al.: Radioprotection 2025, 60( 1), 28 – 36 29 Fig 1. Example of a report provided by the equipment. Quantities such as kV, Air Kerma, KAP, number of exposures, exposure time and date of examination are made available in the form of an image.
tion
is more flexible than that of nationalDRLs( Semghouli et al., 2024). Therefore, it is essential to create methodologies for collecting dosimetric quantities that allow the calculation of Typical Dose and the determination of LDRLs.
In the case of Interventional Radiology procedures, the Air Kerma( or input Kerma at the interventional reference point) or Kerma-Area Product( KAP) quantities are commonly provided by the angiography equipment. This methodology, however, requires mobility and time from the institution’ s team of medical physicists. It is therefore necessary to create innovative methodologies that allow the collection of this information quickly and on a large scale. In the evaluated institution, the ArtisZee Ceiling ®( Siemens Healthineers, Germany) angiographic equipment, is used in hemodynamic procedures.
Another interest is the estimation of the biological risk to which the patient population is exposed during invasive procedures. The PCXMC 2.0 software is a Monte Carlo simulation software that receives dosimetric parameters( air Kerma or KAP) as input to calculate the history of x-ray photons and allows customization regarding the projection used, additional filtration, focus-detector distance, skin focus, irradiated region, among others( Tapiovaara and Siiskonen 2008) and provides the calculation of Effective Dose( E) according to ICRP 103 weighting factors. In this way, once the dosimetric value for the evaluated procedure is known, the estimated value for that patient and procedure can be calculated. Thus, the objective of this work was, based on data collection using a semiautomatic software, to determine LDRLs for the main hemodynamic procedures of a large hospital, compare with typical values from other institutions and use the LDRLs as input in PCXMC 2.0 Monte Carlo simulation software for E estimation.
2 Methods
The study was carried out in a large Brazilian hospital, which has a dedicated hemodynamics sector with a monoplane Artis Zee ®( Siemens Healthineers, Germany) C-arm. At the end of each procedure, this equipment provides a report in the form of an image containing, in addition to information regarding the type of procedure in the Digital Imaging and Communications in Medicine( DICOM) header, technique used, KAP and nominal Air Kerma, the number of exposures in cine mode and the total exposure time. Unfortunately, information regarding dosimetry is stored in the DICOM image and not in the DICOM reader, which makes it difficult the access to this information in an automatic way. As in Radiation Dose Management Systems( RDMS) when the DICOM dosimetric data is not available the RDMS analyses the screenshot dose report by Optical Character Recognition( OCR)( Riccardi et al., 2018; Loose et al., 2021) This way, we developed a software to extract these information’ s using OCR technology( TulioGSMarques, 2024). This software receives as input the final report of the procedure in DICOM format, as shown in Figure 1.
The software then converts the DICOM file into a PNG file, in which it reads the pixel arrangement and associates it into letters and numbers, extracting the information about Air Kerma( K) in the equipment’ s reference point, Kerma-Area product( KAP) in the equipment’ s reference point, number of exposures in cineangiography mode( N), and procedure time( T). The software received all performed procedures on the C-arm equipment of a large hospital performed from January 2021 to September 2023. The workflow of the authoring software for data collection is illustrated on Figure 2.