RESUMEN
We report the radiologic findings from three cases of solitary plasmacytoma (SP) of the sacrum. Common findings included lytic changes on computed tomography (CT) and relatively low signal intensity on T2-weighted magnetic resonance (MR) images, with intense enhancement after contrast administration. All cases showed infiltrating and slightly expansive growth, but the sacral structure was generally maintained. These radiologic findings may be of utility when generating a differential diagnosis of a solitary sacral tumor.
Asunto(s)
Plasmacitoma/diagnóstico , Sacro , Neoplasias de la Columna Vertebral/diagnóstico , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Plasmacitoma/diagnóstico por imagen , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
PURPOSE: To compare the use of multislice continuous arterial spin labeling (CASL) and CO(2) positron emission tomography (PET) to assess CBF in patients with chronic occlusive cerebrovascular disease for the validation of quantitative CASL perfusion in an altered hemodynamic state. MATERIALS AND METHODS: Eleven patients with occlusive carotid artery disease were studied with CASL and conventional MRI. Cerebral blood flow (CBF) was also measured with O(15)-labeled CO(2) gas using a whole-body PET scanner. The average values within region of interests (ROIs) drawn on coregistered CASL and PET images were used for the linear regression analysis and to assess the effect of transit time on the quantification using CASL. RESULT: In all patients there was a significant correlation between the CBF values from CASL and PET (r = 0.71 +/- 0.07, P < 0.001). The slope of regression lines varied widely among patients (0.54-1.77). Longer transit times were estimated in four of 11 patients in the hypoperfusion region. CONCLUSION: Quantification of CBF using CASL is feasible and reasonable, even when employed in a routine clinical setting. However, the long transit time may lead to underestimation of the affected side in occlusive cerebrovascular disease.
Asunto(s)
Isquemia Encefálica/diagnóstico , Estenosis Carotídea/diagnóstico , Trastornos Cerebrovasculares/diagnóstico , Imagen de Difusión por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador , Anciano , Análisis de los Gases de la Sangre , Circulación Cerebrovascular , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Probabilidad , Estudios Prospectivos , Valores de Referencia , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Resistencia VascularRESUMEN
RATIONALE AND OBJECTIVE: To evaluate the vascularity and vascular leakage of well-enhanced gliomas by double-echo dynamic magnetic resonance (MR) imaging. MATERIALS AND METHODS: Eight patients with glioblastoma multiforme (GBM) and two patients with juvenile pilocytic astrocytoma (JPA) were studied. Double-echo dynamic MR imaging was utilized to separate the T2* shortening effect and the T1 shortening effect. The former was represented by the vascularity index, and the latter was represented by the leakage index. These indexes were compared with histopathologic data. RESULTS: The mean vascularity index of the GBM was higher than that of the JPA (mean +/- SD, 3.48 +/- 1.57 [GBM] versus 0.51 +/- 0.29 [JPA]), and the mean leakage index of the JPA was higher than that of the GBM (1.35 +/- 0.87 [JPA] versus 0.27 +/- 0.15 [GBM]). Abundant vascularity was noted in the tight interstitial space in the pathologic specimen of GBM. Conversely, sparse vasculature was observed in the wide interstitial space in the pathologic specimen of JPA. CONCLUSION: This method may enable better characterization of grade in well-enhanced glioma by providing the information on the vascularity and leakage indexes.