Administered radiopharmaceutical activities in diagnostic nuclear medicine and reference level (DRL) for Brazilian country

Abstract

Since discovery of X-ray in 1895, ionizing radiation has been extensively used by the society, specially in the scientific and medical area. The number of radiological and nuclear medicine procedures have increased in about 10%/year and 5%/year, respectively; where this increment is associated to the introduction of PET/CT technology in clinical routine. When increasing the number of these medical procedures, the radiation exposure and radiological risk have even increased to patients, health professionals, and to the environment. Thus, it is necessary to maintain the control of these medical procedures and reduce the radiation exposure to a minimum as possible without interfering in the accuracy of diagnostic imaging. One useful tool for controlling and reducing the radiation exposure in this field is to establish a guide called "diagnostic reference level (DRL)" and to implement standard nuclear medicine procedures according to the International Commission on Radiation Protection (ICRP) and International Atomic Energy Agency (IAEA) recommendations. The DRL has the primary aim of controlling radiation doses and optimizing the medical procedures, but it even permits to evaluate the types of nuclear medicine procedures and the amount of radioisotopes activities that have been undertaken in a geographical area, this aiming to establish the most appropriate amount of radioisotope activity to be administered to patients according to the technique and equipment used for patient imaging, and to provide corrective actions when reference activity level is exceeded without clinical justification. By applying the DRL, it is possible to reduce the radiation exposure to health professionals and to the environment, thus by diminishing the number of medical imaging, administered radioisotope activities or the potential of contamination from these radioactive substances.Nonetheless, the DRL guide does not exist for nuclear medicine in Brazilian country, and this permitting to create a scenary propitious for undertaking non-standardized nuclear medicine procedures, losing the control of radiation exposure over patients and increasing the radiological risks in this medical practice. Thus, the primary aim of this scientific project is to do a screening in Brazilian country looking for providing representative data, such as the level of administered radioisotope activities, nuclear medicine equipments and techniques adopted in this territory, to develop a local DRL and furnishing data for radiological risk controlling. (AU)