Diagnostic reference levels and median doses for common clinical indications of CT: findings from an international registry

Abstract

Ob jectives The European Society of Radiology identified 10 common indications for computed tomography (CT) as part of the European Study on Clinical Diagnostic Reference Levels (DRLs, EUCLID), to help standardize radiation doses. The objective of this study is to generate DRLs and median doses for these indications using data from the UCSF CT International Dose Registry. Methods Standardized data on 3.7 million CTs in adults were collected between 2016 and 2019 from 161 institutions across seven countries (United States of America (US), Switzerland, Netherlands, Germany, UK, Israel, Japan). DRLs (75th percentile) and median doses for volumetric CT-dose index (CTDIvol) and dose-length product (DLP) were assessed for each EUCLID category (chronic sinusitis, stroke, cervical spine trauma, coronary calcium scoring, lung cancer, pulmonary embolism, coronary CT angiography, hepatocellular carcinoma (HCC), colic/abdominal pain, appendicitis), and US radiation doses were compared with European. Results The number of CT scans within EUCLID categories ranged from 8,933 (HCC) to over 1.2 million (stroke). There was greater variation in dose between categories than within categories (p < .001), and doses were significantly different between categories within anatomic areas. DRLs and median doses were assessed for all categories. DRLs were higher in the US for 9 of the 10 indications (except chronic sinusitis) than in Europe but with a significantly higher sample size in the US. Conclusions DRLs for CTDIvol and DLP for EUCLID clinical indications from diverse organizations were established and can contribute to dose optimization. These values were usually significantly higher in the US than in Europe. Key Points • Registry data were used to create benchmarks for 10 common indications for CT identified by the European Society of Radiology. • Observed US radiation doses were higher than European for 9 of 10 indications (except chronic sinusitis). • The presented diagnostic reference levels and median doses highlight potentially unnecessary variation in radiation dose.

Typical Diagnostic Reference Levels of Common Indications for Computed Tomography Scans Among Adult Patients in Uganda: a Cross-sectional Study

“…In this study, IB-DRLs for common indications of CT examinations among adults were developed as typical DRLs set at the 50 th percentile of the pooled distribution of dose data from 12% (3/25) of the CT scanners in Uganda, a low-income country. The common CT scan indications were similar to those in a study within Ghana and in Europe (10,21).…”

“…In the abdomen, a higher-than-expected number of scan sequences were used for UC contrary to a single noncontrast sequence which is usually adequate as calculi provide high contrast to visualize them easily (4,27). Many postcontrast scan sequences were used in UC and ABPL mainly due to absence of standardized scan protocols optimized for these indications and these ndings differed from other studies that used one noncontrast scan sequence for UC and one postcontrast scan sequence for ABDPL in Ghana, France and Europe (10,20,21).…”

Dosis de radiación en tomografía computarizada: observación en tres hospitales de la Región de Valparaíso, Chile

“…El propósito aquí no es establecer un modelo explicativo de dosis, sino más bien obtener una descripción de las dosis resultantes en pacientes y subrayar algunas pistas por las cuales podría ajustarse más la dosis final a paciente. Como se ha señalado 10,11,16 , no solo las características técnicas de las máquinas impactan en la dosis final, sino también las decisiones de implementación de los protocolos. Si bien en la dosis final a paciente impactan múltiples factores de manera no trivial, se destaca aquí la relevancia del número de serie incluido en el examen y del factor de exposición utilizado (mAs).…”

“…Se encuentra en particular el uso de sistemas de control automático de intensidad de la corriente del tubo 7 , o de métodos de reconstrucción iterativos que permiten disminuir significativamente la dosis a paciente 8,9 . Las discusiones siguen activas en el ámbito internacional para acordar los diferentes niveles de referencia de dosis observados en los países 10 , según indicaciones clínicas 11 , y sobre cómo seguir optimizando la dosis de radiación en la TC 2 . En esta línea de trabajo, una cuestión esencial es poder tener datos y saber qué pasa en forma concreta en nuestra realidad local.…”

Diagnostic reference level quantities for adult chest and abdomen-pelvis CT examinations: correlation with organ doses

“…A complete guidance for the DRL practical application is presented in the ICRP 135 [5]. This publication emphasizes that the DRLs must adopt measurable quantities in order to assess and compare doses for particular types of examinations among different facilities and can be used as a tool to optimize medical exposures [6][7][8].…”