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Tracking radiation exposure of patients

Medical imaging using X-rays has been one of the most popular imaging modalities ever since the discovery of X-rays 125 years ago. With unquestionable benefits, concerns about radiation risks have frequently been raised. Computed tomography (CT) and fluoroscopic guided interventional procedures have the potential to impart higher radiation exposure to patients than radiographic examinations. Despite technological advances, there have been instances of increased doses per procedure mainly because of better diagnostic information in images. However, cumulative dose from multiple procedures is creating new concerns as effective doses >100 mSv are not uncommon. There is a need for action at all levels. Manufacturers must produce equipment that can provide a quality diagnostic image at substantially lesser dose and better implementation of optimization strategies by users. There is an urgent need for the industry to develop CT scanners with sub-mSv radiation dose, a goal that has been lingering. It appears that a new monochromatic X-ray source will lead to replacement of X-ray tubes all over the world in coming years and will lead to a drastic reduction in radiation doses. This innovation will impact all X-ray imaging and will help dose reduction. For interventional procedures, the likely employment of robotic systems in practice may drastically reduce radiation exposures to operators- but patient exposure will still remain an issue. Training needs always need to be emphasized and practiced.

To determine the effect on patient radiation exposure of the combined use of a patient dose monitoring system and real-time occupational dose monitoring during fluoroscopically guided interventions (FGIs).

Patient radiation exposure, in terms of the kerma area product (KAP; Gy ∙ cm²), was measured in period 1 with a patient dose monitoring system, and a real-time occupational dose monitoring system was additionally applied in period 2. Mean/median KAP in 19 different types of FGIs was analyzed in both periods for two experienced interventional radiologists combined as well as individually. Patient dose and occupational dose were correlated, applying Pearson and Spearman correlation coefficients.

Although FGIs were similar in numbers and types over both periods, a substantial decrease was found for period 2 in total mean ± SD/median KAP for both operators together (period 1, 47 Gy ∙ cm² ± 67/41 Gy ∙ cm²; period 2, 37 Gy ∙ cm² ± 69/34 Gy ∙ cm²) as well as for each individual operator (for all, P < .05). Overall, KAP declined considerably in 15 of 19 types of FGIs in period 2. Mean accumulated dose per intervention was 4.6 µSv, and mean dose rate was 0.24 mSv/h. There was a strong positive correlation between patient and occupational dose (r = 0.88).

Combined use of a patient dose monitoring system and a real-time occupational dose monitoring system in FGIs significantly lessens patient and operator doses.

Actualmente, existe consenso en la comunidad internacional, tanto en la necesidad como en los beneficios del registro sistemático y planificado de los indicadores de dosis a los pacientes en las exposiciones médicas con radiación ionizante, con principal interés en el registro y seguimiento de las técnicas y procedimientos que pueden implicar un mayor riesgo para los pacientes derivado del uso de la radiación. Este registro debe ser planificado con la estructura y herramientas necesarias para que se tenga en cuenta la seguridad radiológica del paciente, permitiendo al médico solicitante del estudio acceder a la información más relevante del registro, con el objeto de justificar adecuadamente la petición de los nuevos estudios a realizar. Asimismo, debería considerarse una prioridad el establecimiento de niveles de referencia diagnósticos para las distintas magnitudes que se definan en función de la modalidad y prestación a realizar, siendo de gran interés el conocimiento de esta información por el personal involucrado en la realización de los procedimientos con radiaciones ionizantes.

There is a consensus in the international community regarding both the need for and benefits of systematic registration and planning of the dosage indicators in patients exposed to ionizing radiation. The main interest is in the registration and follow-up of the techniques and procedures that can involve the greatest risk from exposure to radiation. This register should be planned to include the structure and tools necessary to take the radiological safety of the patients into account, enabling the physicians requesting the studies to access the most important information in the register so they can appropriately justify the request for additional studies. Likewise, it should be considered a priority to establish diagnostic reference levels for the different magnitudes that are defined in function of the modality and techniques used; this information is useful for the staff involved in procedures that use ionizing radiation.

Exposure to ionizing radiation is a consequence of many diagnostic and interventional cardiac procedures. Radiation exposure can result in detrimental health effects because of deterministic (eg, skin reaction) and stochastic effects (eg, cancer). However, with the levels experienced during cardiac procedures these risks can be difficult to quantify. Healthcare providers and patients might not fully appreciate radiation-related risks. Though in many cases radiation exposure cannot be avoided, a practice of minimizing exposures to levels “as low as reasonably achievable” (ALARA principle) without compromising the utility of the procedure is encouraged. The purpose of this document is to inform health care providers on the key concepts related to radiation risk from common cardiac procedures and provide specific recommendations on ensuring quality of care.

L'exposition au rayonnement ionisant est la conséquence de plusieurs actes de cardiologie diagnostique et interventionnelle. L'exposition au rayonnement peut entraîner des effets préjudiciables à la santé en raison d'effets déterministes (par ex. la réaction cutanée) et stochastiques (par ex. le cancer). Cependant, moyennant les niveaux d'intensité subis durant les actes de cardiologie, ces risques peuvent être difficiles à quantifier. Les prestataires de soins et les patients pourraient ne pas réaliser pleinement les risques liés au rayonnement. Bien que dans plusieurs cas l'exposition au rayonnement ne puisse être évitée, la pratique d'une radioprotection par une exposition à une intensité « aussi faible que raisonnablement possible » (principe ALARA : as low as reasonably achievable) ne compromettant pas l'utilité de l'acte est encouragée. Le but de ce document est d'informer les prestataires de soins sur les concepts principaux liés au risque du rayonnement provenant des actes habituels en cardiologie et de fournir des recommandations particulières pour assurer des soins de qualité.