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2.
Prostate ; 75(16): 1934-40, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26356236

RESUMEN

BACKGROUND: The first evaluation of pelvic extended lymph node dissection (pLND) in oligometastatic prostate cancer (PCa) detected by (68)Ga-PSMA PET/CT. METHODS: Retrospective analysis of 35 PCa patients underwent (68)Ga-PSMA PET/CT affected by biochemical recurrence (BCR) after curative treatment (n = 23) or before primary therapy of high-risk PCa (n = 12). We performed pLND associated with pathologic imaging in 17 men with nodal oligometastatic PCa. RESULTS: Indicative lesions for PCa in PET/CT were detected in 91.4% (32 of 35) of patients. Nodal, bone, visceral (pulmonary), and within the prostate suspected disease were detected in 72% (23 of 32), 16% (5 of 32), 6% (2 of 32), and 47% (15 of 32) of patients, respectively. Median serum PSA in patients with pathological radiotracer uptake in recurrent and high-risk PCa patients was 2.9 ng/ml (range 0.18-30) and 19.5 ng/ml (range 6-90), respectively. The median number of removed lymph nodes with pLND in recurrent and high-risk PCa was 10 (range 4-17) and 12 (range 8-29) per patient and the median number of positive lymph nodes was 1 (range 1-2) and 3 (2-3) per patient, respectively. In total, two false positive and one false-negative lymph node were found. Diagnostic accuracies per nodal lesion in total of 213 removed nodes: sensitivity, 94%; specificity, 99%; positive predictive value (PPV), 89%, and negative predictive value (NPV), 99.5%. After pLND, 53% (9 of 17) of patients received androgen deprivation therapy and/or radiation therapy and hormonal therapy, while 47% (8 of 17) of patients remained free of any post-surgery therapy. Follow-up PSA remained less than 0.2 ng/ml in 82% (14 of 17) of patients. After pLND, immediate BCR (PSA never measured less than 0.2 ng/ml) in 18% (3 of 17) of patients was recorded. CONCLUSIONS: This represents the first study of pLND in the setting of nodal oligometastatic PCa detected by (68)Ga-PSMA PET/CT. The use of (68)Ga-PSMA PET/CT could be to improve the accuracy for the detection of nodal micrometastases. These promising findings need validation in larger studies.


Asunto(s)
Escisión del Ganglio Linfático , Metástasis Linfática/patología , Neoplasias de la Próstata/cirugía , Anciano , Humanos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Imagen Multimodal , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Prostatectomía , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Br J Radiol ; 87(1039): 20130727, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24827377

RESUMEN

OBJECTIVE: To calculate and evaluate absolute quantitative myocardial perfusion maps from rest first-pass perfusion MRI. METHODS: 10 patients after revascularization of myocardial infarction underwent cardiac rest first-pass perfusion MRI. Additionally, perfusion examinations were performed in 12 healthy volunteers. Quantitative myocardial perfusion maps were calculated by using a deconvolution technique, and results were compared were the findings of a sector-based quantification. RESULTS: Maps were typically calculated within 3 min per slice. For the volunteers, myocardial blood flow values of the maps were 0.51 ± 0.16 ml g(-1) per minute, whereas sector-based evaluation delivered 0.52 ± 0.15 ml g(-1) per minute. A t-test revealed no statistical difference between the two sets of values. For the patients, all perfusion defects visually detected in the dynamic perfusion series could be correctly reproduced in the maps. CONCLUSION: Calculation of quantitative perfusion maps from myocardial perfusion MRI examinations is feasible. The absolute quantitative maps provide additional information on the transmurality of perfusion defects compared with the visual evaluation of the perfusion series and offer a convenient way to present perfusion MRI findings. ADVANCES IN KNOWLEDGE: Voxelwise analysis of myocardial perfusion helps clinicians to assess the degree of tissue damage, and the resulting maps are a good tool to present findings to patients.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Imagen de Perfusión Miocárdica/métodos , Adulto , Anciano , Angiografía Coronaria/métodos , Circulación Coronaria/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología
5.
Radiologe ; 52(3): 263-6, 2012 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-22290454

RESUMEN

A 53-year-old female patient presented with splenomegaly, uncertain lesions of the spleen, pancytopenia and suspected aortitis. Reduced strength and muscular pain but no B symptoms were also present. Alterations of the spleen had been known for a long time. Blood examination, laboratory tests and magnetic resonance imaging (MRI) confirmed an aortitis. Concerning the splenic changes neither ultrasound nor MRI could provide conclusive or even pathognomonic findings. Because of an existing pancytopenia and diagnostic obscurity, the patient underwent splenectomy. The histological diagnosis was finally concluded as multifocal littoral cell angioma.


Asunto(s)
Hemangioma/complicaciones , Hemangioma/diagnóstico , Imagen por Resonancia Magnética , Bazo/patología , Neoplasias del Bazo/complicaciones , Neoplasias del Bazo/diagnóstico , Esplenomegalia/diagnóstico , Esplenomegalia/etiología , Femenino , Humanos , Persona de Mediana Edad
6.
Cardiovasc Intervent Radiol ; 35(1): 198-202, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21431968

RESUMEN

Spontaneous rupture of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is a rare and life-threatening complication. Pathophysiologic mechanisms are not yet fully known; it is suggested that rupture is preceded by reactive tissue edema and intratumerous bleeding, leading to a rapid expansion of tumour mass with risk of extrahepatic bleeding in the case of subcapsular localisation. This case report discusses a sudden, unexpected lethal complication in a 74 year-old male patient treated with TACE using DC Bead loaded with doxorubicin (DEBDOX) in a progressive multifocal HCC.


Asunto(s)
Carcinoma Hepatocelular/terapia , Doxorrubicina/administración & dosificación , Neoplasias Hepáticas/terapia , Anciano , Angiografía , Medios de Contraste/administración & dosificación , Resultado Fatal , Humanos , Yopamidol/administración & dosificación , Yopamidol/análogos & derivados , Masculino , Microesferas , Rotura Espontánea , Tomografía Computarizada por Rayos X
7.
Magn Reson Med ; 67(1): 246-50, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21630345

RESUMEN

The response of myocardial blood flow to sympathetic stimulation with cold is modulated by endothelium-related factors. As endothelial dysfunction is an early step in patients with coronary artery disease, the aim of this study was to establish a cold pressor test (CPT) setting for quantitative analysis of myocardial perfusion in a MR scanner. First pass perfusion studies were performed in 10 healthy volunteers using a 1.5 T MR scanner with a multislice steady state free precession perfusion trueFISP sequence in prebolus technique (1 cc/4 cc gadobenate dimeglumine). MR-CPT was established using an over head ice-water bath of the left hand. First pass perfusion imaging was started after 1 min to assure an adequate stimulus followed by a second series after 15 min to evaluate the rest perfusion. After motion correction images were segmented with an adapted, automated tool, myocardial contours were determined. Perfusion was quantitatively evaluated after contamination and baseline correction by deconvolution with the arterial input function using an exponential function model as residuum. All data could be evaluated. Mean myocardial perfusion rose from 0.61 ± 0.22 cc/g/min at rest to 1.15 ± 0.34 cc/g/min under CPT. MR myocardial perfusion values show a comparable increase under CPT as published positron emission tomography data. Consequently, CPT for the presence of endothelial dysfunction is feasible in the MR environment.


Asunto(s)
Frío , Circulación Coronaria/fisiología , Ventrículos Cardíacos/anatomía & histología , Angiografía por Resonancia Magnética/métodos , Imagen de Perfusión Miocárdica/métodos , Función Ventricular Izquierda/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
8.
Rofo ; 182(8): 676-81, 2010 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-20563957

RESUMEN

PURPOSE: The aim of this study was to perform high-resolution functional MR imaging using accelerated density-weighted real-time acquisition (DE) and a combination of compressed sensing (CO) and parallel imaging for image reconstruction. MATERIALS AND METHODS: Measurements were performed on a 3 T whole-body system equipped with a dedicated 32-channel body array coil. A one-dimensional density-weighted spin warp technique was used, i. e. non-equidistant phase encoding steps were acquired. The two acceleration techniques, compressed sensing and parallel imaging, were performed subsequently. From a complete Cartesian k-space, a four-fold uniformly undersampled k-space was created. In addition, each undersampled time frame was further undersampled by an additional acceleration factor of 2.1 using an individual density-weighted undersampling pattern for each time frame. Simulations were performed using data of a conventional human in-vivo cine examination and in-vivo measurements of the human heart were carried out employing an adapted real-time sequence. RESULTS: High-quality DECO real-time images using parallel acquisition of the function of the human heart could be acquired. An acceleration factor of 8.4 could be achieved making it possible to maintain the high spatial and temporal resolution without significant noise enhancement. CONCLUSION: DECO parallel imaging facilitates high acceleration factors, which allows real-time MR acquisition of the heart dynamics and function with an image quality comparable to that conventionally achieved with clinically established triggered cine imaging.


Asunto(s)
Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Cinemagnética/métodos , Contracción Miocárdica/fisiología , Algoritmos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Artefactos , Inteligencia Artificial , Diástole/fisiología , Disnea/etiología , Disnea/fisiopatología , Diseño de Equipo , Humanos , Aumento de la Imagen/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Imagen por Resonancia Cinemagnética/instrumentación , Sensibilidad y Especificidad , Programas Informáticos , Sístole/fisiología
9.
Dtsch Med Wochenschr ; 134(19): 985-8, 2009 May.
Artículo en Alemán | MEDLINE | ID: mdl-19401964

RESUMEN

HISTORY AND ADMISSION FINDINGS: A 53-year-old man with jaundice was referred with suspected cholangiocarcinoma of the porta hepatis. He was found to be in a reduced general and nutritional condition. Cholinesterase was decreased, total bilirubin, GOT, GPT and alkaline phosphatase were increased. INVESTIGATIONS: Abdominal contrast-enhanced computed tomography revealed a centrally located and contrast-enhancing mass at the proximal common hepatic duct. Metastases were not detectable. Endoscopic retrograde cholangiography showed a stenosis of the proximal common hepatic duct. An additional magnetic resonance tomography with cholangio-pancreatography confirmed the centrally located tumor as well as the stenosis of the common hepatic duct. DIAGNOSIS, TREATMENT AND COURSE: The diagnostic tests were suggestive of a stage IV cholangiocarcinoma of the porta hepatis (Klatskin's tumor). The origin was subsequently proven histologically. There was no evidence of intra- or extrahepatic metastases. An interventional embolization of the right portal vein was performed preoperatively to stimulate the growth of the left hepatic lobe. But before surgery could take place a percutaneous transhepatic cholangiography and biliary drainage had to be done followed by an extended right-sided hemihepatectomy. During a 12 month follow-up no recurrence was observed. CONCLUSION: Klatskin's tumor is rare and requires interdisciplinary collaboration. Recent developments in diagnostic, interventional and surgical methods result in a better prognosis.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/terapia , Conducto Hepático Común , Tumor de Klatskin/diagnóstico , Tumor de Klatskin/terapia , Angiografía de Substracción Digital , Colangiopancreatografia Retrógrada Endoscópica , Diagnóstico Diferencial , Drenaje , Embolización Terapéutica , Hepatectomía , Conducto Hepático Común/diagnóstico por imagen , Conducto Hepático Común/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vena Porta , Radiografía Intervencional , Stents , Tomografía Computarizada por Rayos X
11.
Respir Med ; 102(5): 790-2, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18207720

RESUMEN

Report of an incidental chest X-ray finding of a large vessel dilation at the root of the ascending aorta in a 65-year-old female patient while pre-operative routine diagnostic. Due to prior allergic reaction to iodine contrast agent, non-invasive imaging was performed with magnetic resonance imaging (MRI), where the rare finding of a large aneurysm of the left pulmonary artery was diagnosed. Initial considerations of a surgical intervention were turned down as no clinical symptoms or risk factors were apparent.


Asunto(s)
Aneurisma/diagnóstico , Imagen Eco-Planar , Angiografía por Resonancia Magnética , Arteria Pulmonar , Anciano , Femenino , Humanos , Hallazgos Incidentales
12.
Rofo ; 179(9): 932-7, 2007 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-17705115

RESUMEN

PURPOSE: Cardiomyopathy is a rare but life-threatening disease in children and adolescents. Recent studies reported morphological, functional or metabolic alterations of the heart. We discuss a combined MR imaging and (31)P MR spectroscopy (MRS) protocol allowing the analysis of interdependencies between these parameters. Since normal values of cardiac MR parameters in this age group are not available, we included studies of age-matched healthy adolescents. MATERIALS AND METHODS: 2D-CINE was used to assess left ventricular (LV) parameters. Additional 3D-Chemical Shift Imaging (3D-CSI) and Spectral Localization with Optimal Pointspread Function (SLOOP) reconstruction allowed quantification of the cardiac energy metabolism. Patients (n = 4; all male; age 16.8 +/- 2.9 years) were included on the basis of an echocardiographic diagnosis of possible cardiomyopathy. The same protocol was applied to healthy young volunteers (n = 4; 1 female, 3 male; age 15.5 +/- 0.6 years). RESULTS: The patients had a significantly higher LV mass index compared to the control group (147 +/- 41 g/m (2) versus 97 +/- 16 g/m2; p = 0.04). The other LV parameters (including LV EF with 59 +/- 22 % versus 67 +/- 10 %) showed no significant differences. The phosphocreatine to adenosine triphosphate ratio (PCr/ATP-ratio) of the patients was reduced to 1.71 +/- 0.40 versus 2.44 +/- 0.30 (p = 0.01), combined with a tendency towards decreased PCr concentrations of 9.1 +/- 2.5 versus 7.9 +/- 1.0 mmol/kg. CONCLUSION: The combination of (31)P MR spectroscopy and MR imaging allows quantitative determination of morphologic, functional and metabolic alterations in adolescents with suspected cardiomyopathy in one examination procedure. The reduction of energy metabolism combined with unaltered global function may indicate a primary role of metabolism in the pathogenesis of cardiomyopathies in adolescents.


Asunto(s)
Cardiomiopatías/diagnóstico , Imagen Eco-Planar/métodos , Imagen por Resonancia Cinemagnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Adolescente , Adulto , Factores de Edad , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/etiología , Cardiomiopatías/metabolismo , Cardiomiopatías/fisiopatología , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Hipertrófica/diagnóstico , Interpretación Estadística de Datos , Diagnóstico Diferencial , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Masculino , Volumen Sistólico
13.
Rofo ; 179(9): 938-44, 2007 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-17705116

RESUMEN

PURPOSE: To evaluate the variability of coronary calcium scores depending on the image reconstruction interval using a 64-slice CT scanner. MATERIALS AND METHODS: 30 patients (18 male, 12 female; mean age 57 +/- 9 yrs; mean heart rate 66 +/- 10 bpm) underwent coronary calcium scoring using a 64-slice CT scanner (Somatom Sensation 64, Siemens Medical Solutions, Erlangen) and a standardized scanning protocol. Oral beta-blockers were administered to 12 patients with a baseline heart rate > 70 bpm. Images were reconstructed in 10 % increments from 10 - 100 % of the RR interval. Two blinded experienced observers independently calculated Agatston (AS), calcium mass (MS) and volume scores (VS) for every reconstructed image series. The results were compared to similar studies for 16-slice CT scanners. RESULTS: The mean values and mean coefficients of variation among all patients were as follows: AS, 397 +/- 829, 109 % MS, 88 +/- 225, 154 % VS, 335 +/- 669, 100 %. Regarding the reconstruction intervals, the mean coefficients of variation were as follows: 107 % (AS), 97 % (VS), 116 % (MS). No specific image reconstruction interval with statistically significant lower variability for each score could be identified. High inter-observer agreement was achieved (K = 0.98). With statistical significance (p < 0.05) 10/30 patients (pts) were able to be allocated to more than one risk group (RG): 6 pts = 2 RG; 3 pts = 3 RG; 1 pts = 4 RG. The scores for 5/30 patients were zero for at least one reconstruction interval, but further reconstructions revealed calcifications. The number of patients assignable to different risk groups was significantly lower compared to published data using a 16-slice scanner (p < 0.05). CONCLUSION: Coronary calcium scores determined using a 64-slice scanner display a wide range of variability depending on the image reconstruction interval as already described for 16-slice CT scanners. However, compared to previous studies, our data indicate that this vendor's generation of scanners reduces the influence of score variations on the risk stratification.


Asunto(s)
Calcinosis/diagnóstico por imagen , Enfermedad Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Administración Oral , Antagonistas Adrenérgicos beta/administración & dosificación , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Calcio/metabolismo , Enfermedad Coronaria/metabolismo , Interpretación Estadística de Datos , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
14.
Rofo ; 179(9): 945-52, 2007 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-17705117

RESUMEN

PURPOSE: MR stress perfusion imaging of the heart allows the quantification of myocardial perfusion and the evaluation of myocardial perfusion reserve (MPR) and the ratio of subendocardial to subepicardial perfusion at rest and under adenosine stress. The aim of this study was to evaluate a high-resolution GRAPPA sequence for quantitative MR first pass perfusion imaging in healthy volunteers. MATERIALS AND METHODS: First pass stress and rest perfusion studies were performed on 10 healthy volunteers using a 1.5 T MR scanner with a multislice SR-TrueFISP first pass perfusion sequence with a GRAPPA algorithm (acceleration factor 3) in prebolus technique and an image resolution of 1.8 x 1.8 mm. For the comparison group, we examined 12 different healthy volunteers with a standard first pass perfusion SR-TrueFISP sequence using a resolution of 2.7 x 3.3 mm. Myocardial contours were manually delineated followed by an automatic division of the myocardium into two rings with an equal thickness for the subendo- and subepicardial layer. Eight sectors per slice were evaluated using contamination and baseline correction. RESULTS: Using the GRAPPA sequence, the ratio of subendo- to subepimyocardial perfusion was 1.18 +/- 0.32 for the examination at rest. Under pharmacologically induced stress, the ratio was 1.08 +/- 0.27. For the standard sequence the ratio was 1.15 +/- 0.28 at rest and 1.11 +/- 0.33 under stress. For the high resolution sequence higher mean values for the subendo- to subepimyocardial ratio were obtained with comparable standard deviations. The difference between the sequences was not significant. CONCLUSION: The evaluation of subendomyocardial and subepimyocardial perfusion is feasible with a high-resolution first pass perfusion sequence. The use of a higher resolution to avoid systematic error leads to increased image noise. However, no relevant reduction in the quantitative perfusion values under stress and at rest was able to be depicted.


Asunto(s)
Circulación Coronaria/fisiología , Imagen por Resonancia Magnética/métodos , Adenosina/administración & dosificación , Adenosina/farmacología , Adulto , Algoritmos , Medios de Contraste , Circulación Coronaria/efectos de los fármacos , Electrocardiografía , Estudios de Factibilidad , Femenino , Frecuencia Cardíaca , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Descanso , Estrés Fisiológico/inducido químicamente , Estrés Fisiológico/fisiopatología , Vasodilatadores/administración & dosificación , Vasodilatadores/farmacología
15.
J Pharm Sci ; 68(5): 657-8, 1979 May.
Artículo en Inglés | MEDLINE | ID: mdl-219198

RESUMEN

A differential pulse polarographic procedure was developed for the assay of dimercaptosuccinic acid and tin(II), components of a commercially available pharmaceutical kit for kidney scintigraphy. The method is quantitative and qualitative for both the chelated and unchelated forms of dimercaptosuccinic acid and tin(II) in a mixture of the two.


Asunto(s)
Succímero/análisis , Compuestos de Sulfhidrilo/análisis , Estaño/análisis , Quelantes , Riñón/diagnóstico por imagen , Métodos , Polarografía , Cintigrafía
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