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1.
Clin Radiol ; 71(9): 889-95, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27210245

RESUMEN

AIM: To examine the interpretive performance of digital breast tomosynthesis (DBT) as an adjunct to digital mammography (DM) compared to DM alone in a series of invasive lobular carcinomas (ILCs) and to assess whether DBT can be used to characterise ILC. MATERIALS AND METHODS: A retrospective, multi-reader study was conducted of 83 mammographic examinations of women with 107 newly diagnosed ILCs ascertained at histology. Consenting women underwent both DM and DBT acquisitions. Twelve radiologists, with varying mammography experience, interpreted DM images alone, reporting lesion location, mammographic features, and malignancy probability using the Breast Imaging-Reporting and Data System (BI-RADS) categories 1-5; they then reviewed DBT images in addition to DM, and reported the same parameters. Statistical analyses compared sensitivity, false-positive rates (FPR), and interpretive performance using the receiver operating characteristics (ROC) curve and the area under the curve (AUC), for reading with DM versus DM plus DBT. RESULTS: Multi-reader pooled ROC analysis for DM plus DBT yielded AUC=0.89 (95% confidence interval [CI]: 0.88-0.91), which was significantly higher (p<0.0001) than DM alone with AUC=0.84 (95% CI: 0.82-0.86). DBT plus DM significantly increased pooled sensitivity (85%) compared to DM alone (70%; p<0.0001). FPR did not vary significantly with the addition of DBT to DM. Interpreting with DBT (compared to DM alone) increased the correct identification of ILCs depicted as architectural distortions (84% versus 65%, respectively) or as masses (89% versus 70%), increasing interpretive performance for both experienced and less-experienced readers; larger gains in AUC were shown for less-experienced radiologists. Multifocal and/or multicentric and bilateral disease was more frequently identified on DM with DBT. CONCLUSION: Adding DBT to DM significantly improved the accuracy of mammographic interpretation for ILCs and contributed to characterising disease extent.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Carcinoma Lobular/diagnóstico por imagen , Carcinoma Lobular/patología , Mamografía/métodos , Intensificación de Imagen Radiográfica/métodos , Anciano , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Imagenología Tridimensional/métodos , Persona de Mediana Edad , Imagen Multimodal/métodos , Invasividad Neoplásica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos
2.
Radiol Med ; 118(3): 343-55, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22986693

RESUMEN

PURPOSE: The authors compared the accuracy of diffusion-weighted imaging (DWI) visual analysis (VA) vs. apparent diffusion coefficient quantification (ADC-Q) in assessing malignancy of solid focal liver lesions (FLLs). MATERIALS AND METHODS: Using a 1.5-T system, two radiologists retrospectively assessed as benign or malignant 50 solid FLLs: (a) by VA of signal intensity on DWI images at b=800 s/mm(2) and ADC map; (b) by quantifying lesion ADC. Reference standard included histology or follow-up confirmation of diagnosis by a consensus panel. Receiver operating characteristic (ROC) curve analysis was performed. RESULTS: because of 20 false-negative hepatocellular carcinomas, VA showed lower accuracy than ADC-Q (52.0% VS. 68.0%). however, stratified accuracy for metastases was higher with VA (75.0 VS. 66%). ADC and signal features of malignant and benign FLLs were found to largely overlap. CONCLUSIONS: VA performed worse than ADC-Q for hepatocellular carcinoma and better for metastases. Overall, the accuracy of both methods was limited because of the overlap in visual appearance and ADC values between solid benign and malignant FLLs.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Hepáticas/diagnóstico , Adenoma/diagnóstico , Adenoma/patología , Adulto , Anciano , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Diagnóstico Diferencial , Reacciones Falso Negativas , Femenino , Hiperplasia Nodular Focal/diagnóstico , Hiperplasia Nodular Focal/patología , Hemangioma/diagnóstico , Hemangioma/patología , Humanos , Interpretación de Imagen Asistida por Computador , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Curva ROC , Análisis de Regresión , Estudios Retrospectivos , Sensibilidad y Especificidad , Estadísticas no Paramétricas
3.
Psychol Med ; 42(2): 427-34, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21781374

RESUMEN

BACKGROUND: Prior imaging studies have shown structural, functional and biochemical impairments in patients with generalized anxiety disorder (GAD), particularly in the right hemisphere. In this study we investigated, for the first time to the best of our knowledge, the white-matter microstructure organization in GAD. METHOD: A total of 12 patients with DSM-IV GAD and 15 matched healthy controls underwent a magnetic resonance imaging session of diffusion weighted imaging, exploring white-matter water molecules by the means of apparent diffusion coefficients (ADCs). Regions of interests were placed in the frontal, parietal, temporal and occipital lobes and in the splenium and genu of the corpus callosum, bilaterally. RESULTS: ADC measures were significantly greater in patients with GAD in the right splenium and right parietal cortex compared with healthy controls (p⩽0.002). No significant correlations between ADCs and age or clinical variables were found. CONCLUSIONS: We provide evidence that GAD is associated with disrupted white-matter coherence of posterior right hemisphere regions, which may partly sustain the impaired cognitive regulation of anxiety. Future diffusion imaging investigations are expected to better elucidate the communication between the parietal cortex and other right hemisphere regions in sustaining the cognitive processing of social and emotional stimuli in patients with GAD.


Asunto(s)
Trastornos de Ansiedad/patología , Cuerpo Calloso/patología , Leucoencefalopatías/patología , Lóbulo Parietal/patología , Adulto , Imagen de Difusión por Resonancia Magnética , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad
4.
Radiol Med ; 117(3): 339-53, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22434493

RESUMEN

This text discusses several aspects of doctor-patient communication in radiology, including the origins, advantages, and ethical and legal aspects. Over the last 10 years, radiologists have assumed increasing responsibilities towards patients and society. Patients, who are becoming better informed and more aware about medical issues, have a right to be given a timely diagnosis and want to receive as much information as possible from the radiologist. This has implications for several levels of everyday radiological practice, including the organisation of work, legal and ethical aspects and radiologist training. Better interaction with the patient helps to build a closer, more trusting, relationship with the result that the radiologist will be more motivated in his or her work. Until now, radiologists were not adequately trained to communicate the diagnosis directly and verbally to patients, especially when the diagnosis was unfavourable. It is important to emphasise the need for more specific and practical training in this respect, which is indispensable for future developments of the discipline.


Asunto(s)
Comunicación , Relaciones Médico-Paciente , Radiología , Humanos , Radiología/tendencias
5.
Radiol Med ; 117(7): 1097-111, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22438111

RESUMEN

PURPOSE: This study assessed whether the degree of bile-duct dilatation in liver-transplanted patients is correlated with the time from intervention and the type of underlying biliary stricture. METHODS AND MATERIALS: Fifty-seven 3D magnetic resonance cholangiograms (MRCs) performed on 42 liver-transplanted patients were retrospectively evaluated. Diameter was measured at the level of the extrahepatic bile duct (EBD), right hepatic duct (RHD), left hepatic duct (LHD), anterior and posterior right hepatic ducts (aRHD, pRHD) and left lateral and medial ducts (LLD, LMD). Data were stratified according to the type of biliary stricture (all types, anastomotic, ischaemic-like, mixed) and compared, on a per-examination basis: (a) between two groups based on time from transplantation using a 1-year threshold (nonlongitudinal analysis); (b) among 26 repeated examinations on 11 patients (longitudinal analysis); (c) among different stricture groups. RESULTS: The biliary tree was slightly dilated within 1 year from transplantation (2.9±1.3 to 6.1±3.2 mm). In general, nonlongitudinal analysis showed minimally larger duct size after 1 year (mean +1.4±0.5 mm) despite significant differences at most sites of measurement considering all types of strictures (p<0.01; Mann-Whitney U test). Longitudinal analysis showed diameter increase over time, although without statistically significant differences (p>0.01; Kruskal-Wallis test). No significant difference in bile-duct size was observed when comparing types of stricture (p>0.01; Kruskal-Wallis test). CONCLUSIONS: Biliary dilatation after liver transplantation is mild and develops slowly regardless of the underlying type of stricture, possibly in relation to graft properties. MRC has a potential role as first-line imaging modality for a reliable assessment of biliary dilatation and the presence of a stricture.


Asunto(s)
Conductos Biliares/patología , Pancreatocolangiografía por Resonancia Magnética , Trasplante de Hígado/patología , Adulto , Anciano , Constricción Patológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no Paramétricas
6.
Clin Radiol ; 66(6): 559-65, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21371696

RESUMEN

Although breast lesions are commonly detected because of their hypoechogenicity, some lesions may present with hyperechogenicity due to their histological components. Hyperechogenicity has been shown to be highly predictive of benignity; however, hyperechoic lesions can occasionally be malignant. This article reviews hyperechoic lesions of the breast, describes the underlying histological causes associated with hyperechogenicity, and the sonographic features useful for the differential diagnosis between benign and malignant hyperechoic lesions.


Asunto(s)
Enfermedades de la Mama/diagnóstico por imagen , Ultrasonografía Mamaria/métodos , Adulto , Anciano , Enfermedades de la Mama/clasificación , Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Sensibilidad y Especificidad
7.
Radiol Med ; 116(2): 219-29, 2011 Mar.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21311990

RESUMEN

PURPOSE: The authors evaluated the diagnostic yield of chest multidetector computed tomography (MDCT) in acute pulmonary embolism (PE) and the proportion of other clinically relevant findings in a large cohort of consecutive inpatients and patients referred from the emergency department (outpatients). MATERIALS AND METHODS: A total of 327 radiological reports of chest MDCT scans performed for suspected acute PE in 327 patients (158 men, 169 women; mean age 69 years, standard deviation 17.33 years; 233 inpatients, 94 outpatients) were retrospectively evaluated and classified into four categories: 1, positive for PE; 2, negative for PE but positive for other findings requiring specific and immediate intervention; 3, completely negative or positive for findings with a potential for significant morbidity requiring specific action on follow-up; 4, indeterminate. The distribution of findings by categories among the entire population and inpatients and outpatients separately was calculated (chi-square test, α=0.05). RESULTS: In the entire population, the diagnostic yield (i.e. proportion of cases classified as category 1) was 20.2% (66/327). Proportions of cases classified as categories 2, 3 and 4 were 27.5% (90/327), 44.3% (145/327) and 7.9% (26/327), respectively. No statistically significant difference was found between inpatients and outpatients (p=0.193). CONCLUSIONS: In patients with suspected acute PE, chest MDCT provides evidence of conditions requiring immediate and specific intervention (i.e. categories 1 and 2) in nearly 50% of cases, without differences between inpatients and outpatients.


Asunto(s)
Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Anciano , Distribución de Chi-Cuadrado , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Estadísticas no Paramétricas
8.
Radiol Med ; 116(8): 1250-66, 2011 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21744253

RESUMEN

PURPOSE: This study was performed to assess the role of magnetic resonance cholangiography (MRC) in the clinical decision-making process of referring physicians when managing liver-transplanted patients. MATERIALS AND METHODS: Over a 6-month period, 21 liver-transplanted patients with a suspected biliary complication were referred for MRC. Referring physicians were asked to prospectively state, before and after MRC, the leading diagnosis; the level of confidence (on a 0-100% scale); the most appropriate diagnostic/therapeutic plan. Data analysis assessed was the diagnostic yield of MRC; the proportion of change in the leading diagnosis; the therapeutic efficacy (i.e. proportion of change in the initial diagnostic/therapeutic plan); the diagnostic thinking efficacy (i.e., gain in diagnostic confidence). Statistical significance was assessed with the Mann-Whitney U test. MRC accuracy was also calculated. RESULTS: Data analysis showed a diagnostic yield of 85.7%; a proportion of change in leading diagnosis of 19.0%; a therapeutic efficacy of 42.8%; a diagnostic thinking efficacy for concordant and discordant leading diagnoses of 18.8% and 78.7%, respectively (p<0.01). MRC accuracy was 92.3%. CONCLUSIONS: MRC significantly increased the diagnostic confidence, irrespective of the concordance between pre- and posttest diagnoses. Moreover, MRC determined a change in patient management in a significant proportion of cases, leading to clinical benefits.


Asunto(s)
Enfermedades de los Conductos Biliares/diagnóstico , Pancreatocolangiografía por Resonancia Magnética , Trasplante de Hígado , Adulto , Anciano , Enfermedades de los Conductos Biliares/etiología , Pancreatocolangiografía por Resonancia Magnética/métodos , Femenino , Estudios de Seguimiento , Humanos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Radiol Med ; 115(2): 205-14, 2010 Mar.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-19662340

RESUMEN

PURPOSE: Chest radiography (CXR) of immunocompromised patients has low sensitivity in the early evaluation of pulmonary abnormalities suspected to be infectious. The purpose of the study was to evaluate whether the knowledge of clinical data improves the diagnostic sensitivity of CXR in the particular setting of immunocompromised patients after hematopoietic stem cell transplantation (HSCT). MATERIALS AND METHODS: Sixty-four CXRs of immunocompromised patients with clinically suspected pneumonia were retrospectively and independently evaluated by two radiologists to assess the presence of radiological signs of pneumonia, before (first reading) and after (second reading) the knowledge of clinical data. A chest computed tomography (CT) performed within 3 days was assumed as the standard of reference. For each reading, sensitivity of both radiologists was calculated. RESULTS: Readers showed a sensitivity of 39% and 58.5% for the first reading, and 43.9% and 41.5% for the second reading, respectively. For both readers, these values were not significantly different from those obtained at first reading (McNemar's test, p>0.05). Interobserver agreement at second reading was fair (Cohen test, k=0.33). CONCLUSIONS: The sensitivity of CXR is too low to consider it a stand-alone technique for the evaluation of immunocompromised patients after HSCT with suspected pneumonia, even if the radiologist knows detailed clinical data. For these patients, an early chest CT evaluation is therefore recommended.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Huésped Inmunocomprometido , Neumonía/diagnóstico por imagen , Radiografía Torácica/métodos , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
10.
Maturitas ; 53(1): 59-64, 2006 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-15939560

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the effects of different types of hormone replacement therapy (HRT) on mammographic density. MATERIALS AND METHODS: In a prospective 1-year study, 103 postmenopausal women were randomized to receive tibolone 2.5 mg/die, continuous conjugated equine estrogens 0.625 mg/die plus medroxyprogesterone acetate (MPA) 5mg/die or placebo. Mammograms were performed at baseline and after 12 months of treatment. Mammographic density was quantified according to the Wolfe classification. RESULTS: After 12 months of HRT 16 of the 35 patients (45.1%) receiving continuous combined hormonal therapy showed an increase of breast density change in the Wolfe classification. After treatment with tibolone, an up grading in breast density, according to Wolfe's classification, was found in 2 of the 43 patients (2.3%). No changes were recorded in the 25 patients of the control group. The difference between the group treated with continuous combined hormonal therapy and the control group was highly significant (p<0.001). The difference in breast density between patients in treatment with tibolone and the control group was not statistically significant (p=0.34). DISCUSSION: Continuous combination HRT may be more commonly associated with an increase of mammography density than tibolone treatment.


Asunto(s)
Mama/efectos de los fármacos , Moduladores de los Receptores de Estrógeno/farmacología , Terapia de Reemplazo de Estrógeno/métodos , Estrógenos/farmacología , Mamografía , Acetato de Medroxiprogesterona/farmacología , Norpregnenos/farmacología , Mama/anatomía & histología , Neoplasias de la Mama/diagnóstico por imagen , Moduladores de los Receptores de Estrógeno/administración & dosificación , Estrógenos/administración & dosificación , Estrógenos Conjugados (USP)/administración & dosificación , Estrógenos Conjugados (USP)/farmacología , Femenino , Estudios de Seguimiento , Humanos , Acetato de Medroxiprogesterona/administración & dosificación , Persona de Mediana Edad , Norpregnenos/administración & dosificación , Posmenopausia , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento
11.
Phys Med ; 31(1): 1-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25455442

RESUMEN

PURPOSE: To derive Normal Tissue Complication Probability (NTCP) models for severe patterns of early radiological radiation-induced lung injury (RRLI) in patients treated with radiotherapy (RT) for lung tumors. Second, derive threshold doses and optimal doses for prediction of RRLI to be used in differential diagnosis of tumor recurrence from RRLI during follow-up. METHODS AND MATERIALS: Lyman-EUD (LEUD), Logit-EUD (LogEUD), relative seriality (RS) and critical volume (CV) NTCP models, with DVH corrected for fraction size, were used to model the presence of severe early RRLI in follow-up CTs. The models parameters, including α/ß, were determined by fitting data from forty-five patients treated with IMRT for lung cancer. Models were assessed using Akaike information criterion (AIC) and area under receiver operating characteristic curve (AUC). Threshold doses for risk of RRLI and doses corresponding to the optimal point of the receiver operating characteristic (ROC) curve were determined. RESULTS: The α/ßs obtained with different models were 2.7-3.2 Gy. The thresholds and optimal doses curves were EUDs of 3.2-7.8 Gy and 15.2-18.1 Gy with LEUD, LogEUD and RS models, and µd of 0.013 and 0.071 with the CV model. NTCP models had AUCs significantly higher than 0.5. Occurrence and severity of RRLI were correlated with patients' values of EUD and µd. CONCLUSIONS: The models and dose levels derived can be used in differential diagnosis of tumor recurrence from RRLI in patients treated with RT. Cross validation is needed to prove prediction performance of the model outside the dataset from which it was derived.


Asunto(s)
Lesión Pulmonar Aguda/etiología , Neoplasias Pulmonares/radioterapia , Modelos Estadísticos , Traumatismos por Radiación/etiología , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Riesgo , Seguridad
12.
Cancer Lett ; 133(2): 223-9, 1998 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-10072173

RESUMEN

Multiple prognostic indicators, namely histological grade and immunostaining for estrogen (ER) and progesterone receptors (PgR), MIB 1, bc1-2, and p53, were retrospectively determined on preoperative core biopsies from 75 patients with pT 1 breast carcinoma. The association of the preoperatively evaluated factors with those on the corresponding resected tumors (i.e. nodal status, histological grade, presence or absence of vascular invasion and necrosis) was assessed. In univariate analysis, histological grade on resected tumors was significantly associated with histological grade on core biopsy, p53 expression, MIB1 immunostaining. An inverse association was found between postoperative histologic grade and ER, PgR, and bc1-2. Necrosis was significantly associated with grade, p53, MIB1, and inversely with ER, PgR, and bc1-2. Nodal involvement and vascular invasion were significantly associated with MIB1. In multivariate analysis, histological grade and ER were the only independent core biopsy variables associated with postoperative histological grade and necrosis, respectively. This study showed that image-guided core biopsy is a suitable method that can be used to reveal some characteristics of the tumor biology in a preoperative stage.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma/metabolismo , Carcinoma/patología , Anciano , Biopsia/métodos , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Estudios Retrospectivos , Proteína p53 Supresora de Tumor/análisis
13.
Cancer Lett ; 146(2): 181-8, 1999 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-10656624

RESUMEN

The aim of this study was to evaluate the diagnostic accuracy of large core breast biopsy with the use of the perforated compression grid (PCG) in a series of 106 consecutive mammographically detected breast lesions. The PCG consists in a fenestrated paddle that replaces the usual mammographic compressor. Each hole in the grid is marked by letters and numbers in order to obtain the coordinates of the area to biopsy. By analysing the two orthogonal projections, the depth of the lesion in the breast is calculated. With the breast positioned in the PCG, a skin incision is made. After calculations about the depth of needle insertion, the tip of the needle is inserted proximally to the target area. In such a way, taking into consideration the total running of the needle (23 mm), a correct sampling is assured, and multiple needle passes are performed. Sensitivity was of 90.62 and 90.90%, specificity was of 100 and 95.45% and positive predictive value was of 100 and 90.90% by excluding and including suspicious diagnoses, respectively, for each computation. In conclusion, the study indicated that image-guided core biopsy performed by the approach of PCG is a cost-effective, simple and accurate technique for the diagnosis of breast lesions, and it could be proposed as a low-cost alternative where the stereotactic equipment is not available.


Asunto(s)
Biopsia con Aguja/métodos , Mama/patología , Mamografía , Adulto , Anciano , Anciano de 80 o más Años , Análisis Costo-Beneficio , Reacciones Falso Negativas , Femenino , Humanos , Persona de Mediana Edad
14.
Br J Radiol ; 51(607): 484-93, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-667518

RESUMEN

Tomography of the right upper quadrant after the rapid intravenous infusion of a high dose of contrast medium is a valuable method of investigation of hepato-biliary disease. Gall-bladder wall opacification may be normal, but if the wall is thicker than 2 mm and if irregular, it indicates inflammatory or calculous disease. Gall-bladder area greater than 35 cm2 indicates bile duct obstruction. This also causes the ducts to appear as lucent bands within the opacified liver parenchyma. Secondary deposits in the liver may also become visible. Various patterns of these findings are described which suggest specific biliary abnormalities.


Asunto(s)
Sistema Biliar/diagnóstico por imagen , Colecistografía , Colestasis/diagnóstico por imagen , Adulto , Anciano , Colangiografía , Femenino , Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía por Rayos X
15.
Br J Radiol ; 50(595): 483-8, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-871598

RESUMEN

The value of a high dose infusion technique using urographic contrast medium followed by tomography was studied in 44 patients with liver disease. The method was found to be of value in showing cysts, abscesses and cystic disease of the liver. Large tumours, primary and secondary, can also be demonstrated. Normal bile ducts are not visible, but become apparent when they are dilated.


Asunto(s)
Hepatopatías/diagnóstico por imagen , Tomografía por Rayos X , Medios de Contraste/administración & dosificación , Humanos , Neoplasias Hepáticas/diagnóstico por imagen
16.
Br J Radiol ; 63(753): 680-90, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2205327

RESUMEN

In recent years some structures or features such as the "inter-renuncular septum", the "echogenic triangle" and the "echogenic line" have been described to support the concept of a kidney resulting from the fusion of two masses or renunculi. To clarify this concept and to understand the meaning of the above echographic features better, the authors have examined prospectively by sonography the kidneys of 50 children, 200 adults with a single collecting system, 25 adults with a duplicated collecting system and 32 cadavers. Furthermore, to help explain the sonographic features, we have examined 32 cadaver kidneys with sonography and 10 cadaver kidneys with magnetic resonance imaging (MRI). The sonographic, MRI and anatomical correlations have shown that the "echogenic triangle" and the "echogenic line" are not renuncular residuals, but simply an extension of the hilar fat visible when the renal sinus is rather deep. The intermediate cortical mass is not a septum dividing the kidney into an upper and lower renunculus, but a column of parenchymal tissue crossing the renal sinus, which, from an anatomical point of view, is an accessory renal lobe. The presence of two renunculi, suggested in a previous study with cortical nephrotomography, has not been confirmed.


Asunto(s)
Riñón/anatomía & histología , Ultrasonografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estudios Prospectivos
17.
Br J Radiol ; 53(631): 662-7, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7426888

RESUMEN

Ultrasonography was used to evaluate 18 proven cases of carcinoma of the gall-bladder and a prospective diagnosis was correctly achieved in 88.8%. The ultrasonographic findings may be classified into primary and associated. The diagnostic role of ultrasonography is considered and a flow-chart of further investigations is suggested. The diagnostic limits for early detection are underlined.


Asunto(s)
Neoplasias de la Vesícula Biliar/diagnóstico , Ultrasonografía , Anciano , Colestasis Intrahepática/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
Br J Radiol ; 55(656): 558-61, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7116085

RESUMEN

Eleven cases of pancreatic cystadenocarcinoma were studied with respect to the differential diagnosis from that of pancreatic pseudocysts, using diagnostic ultrasound as the initial investigative technique. Most of the cases presented an ultrasonic picture that correlated well with the gross pathology, but this correlation was not reliable enough to be considered characteristic in differentiating such masses from pseudocysts. The authors divide the cystadenocarcinomas of the pancreas into four echographic classes. In all but one of the classes, diagnostic ultrasound was insufficient by itself to render an accurate diagnosis. In such cases other techniques, i.e. CT, tissue biopsy, and especially angiography, were required for a reliable diagnosis.


Asunto(s)
Cistadenocarcinoma/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Ultrasonografía , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Seudoquiste Pancreático/diagnóstico
19.
Eur J Radiol ; 27 Suppl 2: S141-8, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9652514

RESUMEN

INTRODUCTION: Transcranial color Doppler sonography permits the accurate assessment of intracranial arteries. The latest Doppler units, using the color and power techniques, can show even very small flow volumes (1 x 1 mm). Low frequency (2-2.5 MHz) and very focused transducers are used in transcranial color Doppler. The skull is a very strong barrier for ultrasounds, which requires the use of some acoustic windows like some thin portions of the skull bone or some natural skull foramina. The use of echocontrast agents in color Doppler seems to increase the applications of transcranial studies. OBJECTIVE: (1) To report on transcranial color Doppler technique and findings. (2) To assess the role of contrast agents in the visualization of intracranial vessels. (3) To define the main indications of this technique. MATERIAL AND METHODS: The temporal, the orbital and the suboccipital are the main acoustic windows used for transcranial color Doppler studies. We use phased-array transducers (2-2.5 MHz) and, preferrably, the echocontrast agent. We examined 15 patients with severe internal carotid artery stenoses after the infusion of Levovist (Schering AG, Berlin, Germany) suspension (8 ml at 300 mg Galactose/ml, infused at 0.5 ml/s). RESULTS: Levovist infusion permitted to depict the main intracranial vessels in all cases. The middle and the anterior cerebral arteries are shown through the temporal window. The former is the main cerebral artery, it is the easiest to identify and presents the highest peak systolic velocity. The orbital window can be used to visualize the ophthalmic artery and the internal carotid artery siphon, while the vertebral and the basilar arteries are demonstrated through the suboccipital window. DISCUSSION: We report the most important findings and discuss the main indications of transcranial color Doppler studies. In addition to flow presence and direction, the main indices of arterial flow can be measured thanks to contrast agent administration, namely the peak systolic velocity, the end diastolic velocity, the resistance index and the pulsatility index. A morphological assessment of the Willis circle can also be carried out with color and power Doppler. Functional studies can be performed to assess the residual autoregulatory function of the cerebral circle in the patients with internal carotid artery stenosis or occlusion. The development of intracranial collateral circles can also be studied in these patients. Moreover, the M1 segment of the middle cerebral artery and the internal carotid artery siphon can be demonstrated directly. Transcranial color Doppler is also a useful tool to detect vasospasm after subarachnoid hemorrhage and to monitor blood flow velocity in the middle cerebral artery during carotid endarterectomy. The assessment of blood supply to arteriovenous malformations and to intracranial neoplasms is another application. CONCLUSION: With reference to internal carotid stenoses, the main applications of transcranial color Doppler are the study of intracranial vessels, of intracranial arterial stenosis, of arteriovenous malformations and of Willis circle aneurysms, as well as the monitoring of blood flow velocity during carotid endarterectomy. Echocontrast agents play an important role in the visualization of intracranial vessels.


Asunto(s)
Encéfalo/irrigación sanguínea , Medios de Contraste/administración & dosificación , Polisacáridos/administración & dosificación , Ultrasonografía Doppler Transcraneal , Arteriopatías Oclusivas/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Estenosis Carotídea/diagnóstico por imagen , Humanos , Valores de Referencia , Sensibilidad y Especificidad , Hemorragia Subaracnoidea/diagnóstico por imagen , Ultrasonografía Doppler en Color
20.
Eur J Radiol ; 27 Suppl 2: S224-8, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9652526

RESUMEN

Both color Doppler sonography and magnetic resonance are imaging techniques which do not use ionizing radiations, but despite this common feature there remain many differences between them. Thus, color Doppler sonography is a cost-effective technique using mechanical waves and providing real-time images while magnetic resonance imaging is much more expensive, uses magnetic fields and radiofrequency energy and provides static images. The former method is very sensitive in detecting focal liver lesions > 1 cm, but its specificity in characterization is not as good, not even with the color Doppler technique. The main differences between color Doppler sonography, with and/or without echocontrast agents, and contrast-enhanced (Gadolinium chelates) dynamic magnetic resonance imaging in focal liver lesions can be summarized as follows: (1) magnetic resonance imaging depicts tumor vascularization only after paramagnetic contrast media injection. Enhanced images completely depend upon the contrast agent and cannot be achieved without it. In contrast, color Doppler signal is not modified by the contrast agent, it just becomes stronger. (2) Contrast-enhanced magnetic resonance signal (as well as contrast-enhanced computed tomography signal) provides more pieces of information than color Doppler signal about the flow characteristics of liver nodules--i.e. it shows not only blood flow (hyper-/hypovascular nodule), but also the interstitial spread of the agent and its wash-out. For example, hepatocellular carcinoma and focal nodular hyperplasia have similar perfusion while agent spread and wash-out decrease very quickly in the former and more slowly in the latter, except for the low decrease of the central scar. (3) Color Doppler technology improvements, higher sensitivity to slow flows and better signal/noise ratio reduce the applications of contrast-enhanced sonography in focal liver lesions because the agents modify only sensitivity and not the imaging in slow flow studies. (4) The higher cost of contrast studies is justified only in selected cases, namely treatment follow-up in the lesions with rich pretreatment vascularization. Finally, the higher cost of contrast magnetic resonance studies is justified to increase sensitivity and especially to allow lesion characterization.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Medios de Contraste , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética , Ultrasonografía Doppler en Color , Carcinoma Hepatocelular/diagnóstico , Medios de Contraste/administración & dosificación , Gadolinio , Humanos , Neoplasias Hepáticas/diagnóstico , Sensibilidad y Especificidad
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