RESUMEN
PURPOSE: To evaluate the diagnostic value of radial reformatting of axial multislice CT (MS-CT) data sets in the presumptive diagnosis of pulmonary embolism. MATERIALS AND METHODS: In 126 cases with the presumptive diagnosis of an acute pulmonary embolism, 4- and 8-slice axial MS-CT data sets were radially reformatted. The pulmonary vessels were evaluated by five experienced radiologists who determined the number of thrombi at the level of the segmental and subsegmental arteries. A pulmonary artery was considered as thrombosed if it showed at least one unambiguous filling defect on two consecutive sections. It was determined whether the artery was uniformly opacified without filling defects, contained thrombotic material or was completely occluded by a blood clot. Pulmonary vessels that could not be evaluated because of moving artifacts or inadequate opacification were classified as negative. Finally, all experts gave a subjective estimate concerning the simplicity of the diagnosis for both reconstructions. RESULTS: The diagnosis of thromboembolism at a subsegmental level was significantly different for axial sections and radial reconstruction: at 4-slice CT, 77 subsegmental thromboembolisms were found in axial sections vs. 98.6 in radial reconstructions; at 8-slice CT, 23.6 in axial sections vs. 31.2 in radial reconstructions; and using the combined evaluation, 103.2 in axial sections vs. 130.6 in radial reconstructions, with a significance of p = 0.043. The five judges did not find any significant differences in the number of the blood clots in each pulmonary segment. Concerning the simplicity of the diagnosis, the subjective judgment classified the radial reconstructions as better in 49.7 % and the axial sections as better in 22 %. The radial reconstructions of the 4-slice CT were classified as better in 45.7 % vs. 25 % and the 8-slice CT as better in 66 % vs. 16 %. CONCLUSION: Using radial multiplanar reformatting of the MS-CT data sets improves significantly the recognition of subsegmental pulmonary embolism.
Asunto(s)
Procesamiento de Imagen Asistido por Computador , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Artefactos , Medios de Contraste , Interpretación Estadística de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Sensibilidad y Especificidad , Tromboembolia/diagnóstico por imagen , Trombosis/diagnóstico por imagenRESUMEN
After withdrawal of daily treatment with haloperidole (2 mg/kg s.c.) and apomorphine (10 mg/kg s.c.) for 21 days, respectively, and clomipramine (15 mg/kg s.c.) for 28 days, a decrease of morphine analgesia is observed. The findings are interpreted as a sensitivity change of the transmission systems involved in the action mechanism of the antinocifensive morphine effect. Morphine lethality remains unaffected by the synaptic efficiency of the transmission systems investigated.