Interobserver and intraobserver variability in determining breast density according to the fifth edition of the BI-RADS® Atlas. / Estudio de la variabilidad inter- e intraobservador en la determinación de la densidad mamaria según la 5.a edición del Atlas BI-RADS®.

OBJECTIVE: To determine the level of agreement within and between observers in the categorization of breast density on mammograms in a group of professionals using the fifth edition of the American College of Radiology's BI-RADS® Atlas and to analyze the concordance between experts' categorization and automatic categorization by commercial software on digital mammograms. METHODS: Six radiologists categorized breast density on 451 mammograms on two occasions one month apart. We calculated the linear weighted kappa coefficients for inter- and intra-observer agreement for the group of radiologists and between the commercial software and the majority report. We analyzed the results for the four categories of breast density and for dichotomous classification as dense versus not dense. RESULTS: The interobserver agreement among radiologists and the majority report was between moderate and nearly perfect for the analysis by category (κ=0.64 to 0.84) and for the dichotomous classification (κ=0.63 to 0.84). The intraobserver agreement was between substantial and nearly perfect (κ=0.68 to 0.85 for 4 categories and k=0.70 to 0.87 for the dichotomous classification). The agreement between the majority report and the commercial software was moderate both for the four categories (κ=0.43) and for the dichotomous classification (κ=0.51). CONCLUSION: Agreement on breast density within and between radiologists using the criteria established in the fifth edition of the BI-RADS® Atlas was between moderate and nearly perfect. The level of agreement between the specialists and the commercial software was moderate.

Embolia pulmonar grasa: Presentación de un caso / Pulmonary fat embolism. Case report

La embolia grasa (EG) es una obstrucción de los vasos sanguíneos por glóbulos de grasa. Ha sido descrita en la circulación pulmonar con una gran variedad de asociaciones, pero las más comunes e importantes se dan con fracturas de huesos largos y daño de tejido blando debido a traumatismo grave. Por su parte, el síndrome de embolia grasa (SEG) es una manifestación poco frecuente, aunque grave, del fenómeno de embolia grasa, que se caracteriza clínicamente por la tríada disnea, petequias y confusión mental. La razón de la discrepancia entre la presencia de embolia grasa y el desarrollo del síndrome no es clara. Presentamos el caso de un hombre de 41 años que, inmediatamente después del trauma, presentó en la tomografía computada (TC) inicial defectos de llenado de atenuación grasa dentro de las arterias pulmonares. Estos fueron interpretados como múltiples embolias grasas macroscópicas. Los valores de atenuación de la tomografía computada multidetector (TCMD) de las embolias pulmonares deben examinarse cuidadosamente en el contexto de un traumatismo agudo o después de procedimientos ortopédicos, debido a la complicación rara pero potencialmente fatal del SEG. En los centros de trauma, la TCMD es una herramienta esencial para hacer el diagnóstico de la embolia grasa macroscópica, así como también para descartar otras causas de hipoxia, como la embolia pulmonar trombótica. La reconstrucción de cortes finos debe utilizarse para la evaluación detallada de la vasculatura pulmonar.

Fat embolism (FE) may be defined as the blockage of blood vessels by fat globules. Pulmonary fat embolisms are reported to be associated with a wide variety of conditions, with the most common and important ones being with long bone fractures and soft tissue damage due to severe trauma. Fat embolism syndrome (FES) is a rare but serious manifestation of the fat embolism phenomenon, characterized clinically by a triad of dyspnea, petechiae, and mental confusión. The discrepancy between the presence of a fat embolism and the development of fat embolism syndrome is unclear. The case is presented of a 41 year-old mate who, on the initial trauma CT sean, presented with filling defeets of fat attenuation within the pulmonary arteries. Those were interpreted as múltiple macroscopic fat emboli. The CT attenuation valúes of pulmonary embolism should be carefully examined in the setting of acute trauma or after orthopedic procedures, as the rare but potentially fatal complicaron of FES may result. In trauma centers, multidetectorcomputed tomography is an essential tool to make the diagnosis of macroscopic fat embolism, and to exelude other causes of hypoxia, such as thrombotic pulmonary embolism. These reconstructions should be used for detailed evaluation of the pulmonary vasculature.