Computed tomography: current Brazilian scenario

n recent years, computed tomography (CT) has become increasingly important in diagnostic radiology worldwide. The introduction of dual-energy CT and photon-counting computed tomography (PCCT) in clinical use has further expanded diagnostic possibilities with improved image quality without increasing patient dose. Iterative algorithms and deep learning reconstructions also enhance image quality by reducing noise. Efforts to optimize CT procedures are still necessary, as per findings by UNSCEAR 2020. Despite accounting for only 10% of all examinations, CT scans contribute the highest percentage (62.6%) to the overall collective dose. The estimated annual number of CT scans is about 400 million, with an 80% increase in frequency and a 70% increase in collective dose. Currently, Brazil has not established diagnostic reference levels. The limited number of studies conducted in the country does not accurately reflect the situation. Organization websites such as the Unique Public Health System (DATASUS), the National Register of Health Establishments (CNES), and the National Supplementary Health Agency (a private health system) provide official information about CT procedures, including updated data on the number of CT equipment available and the annual number of procedures performed. It is evident from the distribution of CT equipment and population percentages in each region that this imaging modality is concentrated primarily in the Midwest and Southern regions region. The publication of GM/MS ordinance law no.1631/GM on October 1, 2015, established that at least one CT scanner should be available in the public healthcare system for every 100,000 inhabitants or 75 kilometers. According to UNSCEAR 2020, developed countries have a quarter of the world's population and have, on average, 1,332 CT for 1000 inhabitants. Underdeveloped and developing countries have the most significant part of the population, 27% and 49%, respectively. The CTs performed in the first were 20 procedures per 1000 inhabitants and the latter 332, showing the disparity caused by the lack of resources. According to the data from OECD reports, Brazil lags in healthcare investment compared to other countries in US dollars per capita. Being suppressed by countries like Argentina, the United States, and Turkey as of the last report. The high frequency of CT procedures requires implementing patient dose assessment and optimization programs. This article uses the national health system database to evaluate the distribution of CT scanners and the frequency of CT procedures in Brazil from 2016 to 2020. (author)