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1.
Radiologe ; 54(8): 783-91, 2014 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-25085594

RESUMO

Tumors of neuroepithelial tissue represent the largest group of pediatric brain tumors by far and has therefore been divided into several discrete tumor subtypes each corresponding to a specific component of the neuropil. The neuropil contains several subtypes of glial cells, including astrocytes, oligodendrocytes, ependymal cells and modified ependymal cells that form the choroid plexus. This review discusses the imaging aspects of the most common pediatric tumors of neuroepithelial tissue.


Assuntos
Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Neuroepiteliomatosas/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
2.
Nuklearmedizin ; 49(6): 225-33; quiz N60-1, 2010.
Artigo em Alemão | MEDLINE | ID: mdl-20617279

RESUMO

The purpose of these guidelines is to offer the nuclear medicine and the appropriate interdisciplinary team a framework for performing and reporting positron emission tomography (PET) and the combination with computed tomography (PET/CT) in children with malignant diseases mainly using the radiopharmaceutical 18F-fluorodeoxy-glucose (FDG). These guidelines are based on the recent guidelines of the Paediatric Committee of the European Association of Nuclear Medicine (EANM) (57) and have been translated and adapted to the current conditions in Germany. The adaptation of CT-parameters using PET/CT in children is covered in a more detailed way than in the EANM guideline taking into account that in Germany already a good portion of PET examinations is performed using an integrated PET/CT-scanner. Furthermore, a CT-scan without adoption of the CT acquisition parameters would result in a not tolerably high radiation exposition of the child. There are excellent guidelines for FDG PET and PET/CT in oncology published by the German Society of Nuclear Medicine (Deutsche Gesellschaft für Nuklearmedizin, DGN) (42) and EANM (4). These guidelines aim at providing additional information on issues particularly relevant to PET and PET/CT imaging in children. These guidelines should be taken in the context of local and national current standards of quality and rules.


Assuntos
Fluordesoxiglucose F18 , Neoplasias/diagnóstico por imagem , Peso Corporal , Criança , Alemanha , Humanos , Pediatria/métodos , Pediatria/normas , Tomografia por Emissão de Pósitrons , Guias de Prática Clínica como Assunto , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
3.
Nuklearmedizin ; 49(4): 129-37, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20514387

RESUMO

AIM: This study had three major objectives: 1.) to record the number of concordant (both in PET and CT) pathological lesions in different body regions/organs, 2.) to evaluate the image quality and 3.) to determine both, the quantity and the quality of artefacts in whole body FDG PET/CT scans. PATIENTS, METHODS: Routine whole body scans of 353 patients referred to FDG-PET/CT exams at 4 university hospitals were employed. All potentially malignant lesions in 13 different body regions/organs were classified as either concordant or suspicious in FDG-PET or CT only. In the latter case the diagnostic relevance of this disparity was judged. The image quality in PET and CT was rated as a whole and separately in 5 different body regions. Furthermore we investigated the frequency and site of artefacts caused by metal implants and oral or intravenous contrast media as well as the subjective co-registration quality (in 4 body regions) and the diagnostic impact of such artefacts or misalignment. In addition, the readers rated the diagnostic gain of adding the information from the other tomographic method. RESULTS: In total 1941 lesions (5.5 per patient) were identified, 1094 (56%) out of which were concordant. 602 (71%) out of the 847 remaining lesions were detected only with CT, 245 (29%) were only PET-positive. As expected, CT particularly depicted the majority of lesions in the lungs and abdominal organs. However, the diagnostic relevance was greater with PET-only positive lesions. Most of the PET/CT scans were performed with full diagnostic CT including administration of oral and intravenous contrast media (> 80%). The image quality in PET and CT was rated excellent. Artefacts occurred in more than 60% of the scans and were mainly due to (dental) metal implants and contrast agent. Nevertheless there was almost no impact on diagnostic confidence if reading of the non attenuation corrected PET was included. The co-registration quality in general was also rated as excellent. Misalignment mostly occurred due to patient motion and breathing and led to diagnostic challenges in about 4% of all exams. The diagnostic gain of adding PET to a CT investigation was rated higher than vice versa. CONCLUSIONS: As the image quality in both PET and CT was more than satisfying, CT-artefacts almost never led to diagnostic uncertainties and serious misalignment rarely occurred, PET/CT can be considered as suitable for routine use and may replace single PET- and CT-scans. However, additional reading of the non attenuation corrected PET is mandatory to assure best possible diagnostic confidence in PET. Since approximately half of all lesions found in PET/CT were not concordant, at least in a setting with a diagnostic CT the exams need to be reported by both a nuclear medicine physician and a radiologist in consensus.


Assuntos
Artefatos , Tomografia por Emissão de Pósitrons/métodos , Próteses e Implantes , Tomografia Computadorizada por Raios X/métodos , Implantes Dentários , Fluordesoxiglucose F18 , Humanos , Movimento , Especificidade de Órgãos , Tomografia por Emissão de Pósitrons/normas , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/normas
4.
Rofo ; 181(10): 962-9, 2009 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-19517343

RESUMO

PURPOSE: To determine regional and global left ventricular (LV) functional parameters and to perform segmental wall thickness (SWT) and motion (WM) analysis of dual-source CT (DSCT) with optimized temporal resolution versus MRI. MATERIALS AND METHODS: 30 patients with known or suspected CAD, non-obstructive HCM, DCM, ARVCM, Fallot Tetralogy, cardiac sarcoidosis and cardiac metastasis underwent DSCT and MRI. The DSCT and MR images were evaluated: end-systolic (ESV), end-diastolic LV (EDV) volumes, stroke volume (SV), ejection fraction (EF), and myocardial mass (MM) as well as LV wall thickening and segmental WM applying the AHA model were obtained and statistically analyzed. RESULTS: The mean LV-EDV (r = 0.96) and ESV (r = 0.98) as well as LV-EF (r = 0.97), SV (r = 0.83), and MM (r = 0.95) correlated well. Bland Altman analysis revealed little systematic underestimation of LV-EF (-1.1 +/- 7.8 %), EDV (-0.3 +/- 18.2 ml), SV (-1.3 +/- 16.7 ml) and little overestimation of ESV (1.1 +/- 7.8 ml) and MM (12.8 +/- 14.4 g) determined by DSCT. Systolic reconstruction time points correlated well (DSCT 32.2 +/- 6.7 vs. MRI 35.6 +/- 4.4 % RR-interval). The LV wall thickness obtained by DSCT and MRI showed close correlation in all segments (Ø diff 0.42 +/- 1 mm). In 413 segments (89 %) WM abnormalities were equally rated, whereas DSCT tended to underestimate the degree of wall motion impairment. CONCLUSION: DSCT with optimized temporal resolution enables regional and global LV function analysis as well as segmental WM analysis in good correlation with MRI. However, the degree of WM impairment is slightly underestimated by DSCT.


Assuntos
Cardiopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada Espiral/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Volume Cardíaco/fisiologia , Diástole/fisiologia , Feminino , Cardiopatias/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Volume Sistólico/fisiologia , Sístole/fisiologia , Disfunção Ventricular Esquerda/etiologia
5.
Rofo ; 181(7): 683-90, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19241327

RESUMO

PURPOSE: Determination of an adequate scan delay for routine abdominal 64-slice CT examinations with body weight-adapted contrast application. MATERIALS AND METHODS: 57 patients underwent abdominal CT with a 64-slice scanner. The contrast material was adapted to patient body weight. All patients were randomized into five groups with varying scan delay and scan direction (group 1: delay 65 sec; group 2: 75 sec; group 3: 85 sec, craniocaudal; group 4: 85 sec, caudocranial; group 5: 95 sec). Two blinded radiologists evaluated the image quality. CT values (HU) were obtained in different segments of the aorta, inferior vena cava, iliac veins, portal vein, hepatic veins and liver, spleen and pancreas. Statistical analysis was performed using the independent sample t-test and ANOVA test. RESULTS: The diagnostic acceptability of protocols 3 and 4 were rated equally good and significantly/substantially superior to protocol 1 (p = 0.004/0.008) and protocol 5, respectively. Contrast enhancement in the aorta and portal vein peaked at 65 sec. Contrast enhancement in the hepatic and iliac veins peaked at 85 sec independently of the scan direction but was substantially lower at 75 sec. Liver parenchyma enhancement was lowest at 95 sec. CONCLUSION: This data suggests an optimal scan delay for routine abdominal 64-slice CT of 85 sec regardless of scan direction.


Assuntos
Neoplasias Abdominais/diagnóstico por imagem , Neoplasias Abdominais/patologia , Peso Corporal , Meios de Contraste/administração & dosagem , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Iopamidol/análogos & derivados , Tomografia Computadorizada Espiral/métodos , Neoplasias Abdominais/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Aortografia , Artéria Celíaca/diagnóstico por imagem , Artéria Celíaca/patologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/patologia , Humanos , Injeções Intravenosas , Iopamidol/administração & dosagem , Iopamidol/farmacocinética , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Veia Porta/diagnóstico por imagem , Veia Porta/patologia , Baço/diagnóstico por imagem , Baço/patologia , Fatores de Tempo , Adulto Jovem
6.
Rofo ; 181(1): 67-73, 2009 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-18975251

RESUMO

PURPOSE: To assess the accuracy of liver lesion measurement using automated measurement and segmentation software depending on the vascularization level. MATERIALS AND METHODS: Arterial and portal venous phase multislice CT (MSCT) was performed for 58 patients. 94 liver lesions were evaluated and classified according to vascularity (hypervascular: 13 hepatocellular carcinomas, 20 hemangiomas; hypovascular: 31 metastases, 3 lymphomas, 4 abscesses; liquid: 23 cysts). The RECIST diameter and volume were obtained using automated measurement and segmentation software and compared to corresponding measurements derived visually by two experienced radiologists as a reference standard. Statistical analysis was performed using the Wilcoxon test and concordance correlation coefficients. RESULTS: Automated measurements revealed no significant difference between the arterial and portal venous phase in hypovascular (mean RECIST diameter: 31.4 vs. 30.2 mm; p = 0.65; kappa = 0.875) and liquid lesions (20.4 vs. 20.1 mm; p = 0.1; kappa = 0.996). The RECIST diameter and volume of hypervascular lesions were significantly underestimated in the portal venous phase as compared to the arterial phase (30.3 vs. 26.9 mm, p = 0.007, kappa = 0.834; 10.7 vs. 7.9 ml, p = 0.0045, kappa = 0.752). Automated measurements for hypovascular and liquid lesions in the arterial and portal venous phase were concordant to the reference standard. Hypervascular lesion measurements were in line with the reference standard for the arterial phase (30.3 vs. 32.2 mm, p = 0.66, kappa = 0.754), but revealed a significant difference for the portal venous phase (26.9 vs. 32.1 mm; p = 0.041; kappa = 0.606). CONCLUSION: Automated measurement and segmentation software provides accurate and reliable determination of the RECIST diameter and volume in hypovascular and liquid liver lesions. Hypervascular lesions are prone to be underestimated with regard to size in the portal venous phase and therefore should preferentially be segmented in the arterial phase.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/diagnóstico por imagem , Cistos/diagnóstico por imagem , Hemangioma/irrigação sanguínea , Hemangioma/diagnóstico por imagem , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Abscesso Hepático/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Software , Tomografia Computadorizada de Feixe Cônico Espiral/métodos , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Diagnóstico Diferencial , Feminino , Artéria Hepática/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade
9.
Eur J Nucl Med Mol Imaging ; 35(8): 1581-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18536914

RESUMO

OBJECTIVE: The purpose of these guidelines is to offer to the nuclear medicine team a framework that could prove helpful in daily practice. These guidelines contain information related to the indications, acquisition, processing and interpretation of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in paediatric oncology. The Oncology Committee of the European Association of Nuclear Medicine (EANM) has published excellent procedure guidelines on tumour imaging with (18)F-FDG PET (Bombardieri et al., Eur J Nucl Med Mol Imaging 30:BP115-24, 2003). These guidelines, published by the EANM Paediatric Committee, do not intend to compete with the existing guidelines, but rather aim at providing additional information on issues particularly relevant to PET imaging of children with cancer. CONCLUSION: The guidelines summarize the views of the Paediatric Committee of the European Association of Nuclear Medicine. They should be taken in the context of "good practice" of nuclear medicine and of any national rules, which may apply to nuclear medicine examinations. The recommendations of these guidelines cannot be applied to all patients in all practice settings. The guidelines should not be deemed inclusive of all proper procedures or exclusive of other procedures reasonably directed to obtaining the same results.


Assuntos
Fluordesoxiglucose F18 , Oncologia/normas , Neoplasias/diagnóstico , Pediatria/normas , Tomografia por Emissão de Pósitrons/normas , Tomografia Computadorizada por Raios X/normas , Criança , Europa (Continente) , Humanos , Compostos Radiofarmacêuticos
10.
Nuklearmedizin ; 47(1): 30-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18278210

RESUMO

AIM: This study evaluated a MDCT protocol for contrast-enhanced 16-channel PET-CT with regard to scan range and duration of a whole-body (18)F-FDG PET-CT examination, the occurrence of contrast-material induced artefacts and quantitative assessment of CT attenuation. PATIENTS, METHODS: 205 patients (51.9+/-12.4 years) with different malignant tumours underwent whole-body PET-CT; the study protocol had been approved by the institutional review board. Contrast-enhanced MDCT (16 x 1.5 mm; 120 ml Iomeprol 3 ml/s, 50 ml saline chaser bolus, scan delay 70 s; oral contrast) was also used for attenuation correction. From MDCT data mean scan range and duration, occurrence of contrast media-induced artefacts, and mean CT densities of jugular (jv) and subclavian (scv), superior (vcs) and inferior (vci) caval, portal (pv), and bilateral external iliac veins, pulmonary (ap) and iliac arteries, descending thoracic and abdominal aorta, all cardiac chambers, as well as both liver lobes, spleen, adrenal glands and kidneys were determined. RESULTS: Attenuation corrected PET images were free of contrast media-related image artefacts. Homogeneous contrast enhancement was found in the mediastinal veins (right/left jv 171+/-34/171+/-35, scv 127+/-50/127+/-40, vcs 153+/-36 HU) and arteries (e.g. ap 145+/-26/151+/-26). Cardiac chambers, abdominal vessels (e.g. vci 138+/-24, pv 159+/-25 HU), and parenchymal organs revealed sufficient and homogenous contrast-enhancement in all cases. No beam-hardening artefacts occurred in the neighbourhood of the subclavian veins. CONCLUSION: The chosen whole-body (18)F-FDG 16-slice PET-CT protocol allowed for craniocaudal CT scanning with high vessel and parenchymal contrast revealing no IV contrast-media induced artefacts in attenuation-corrected PET data sets.


Assuntos
Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Imagem Corporal Total/métodos , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Linfoma não Hodgkin/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
12.
Eur Radiol ; 17(11): 2941-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17929026

RESUMO

The purpose of this study was to compare sensitivity for detection of pulmonary nodules in MDCT scans and reading time of radiologists when using CAD as the second reader (SR) respectively concurrent reader (CR). Four radiologists analyzed 50 chest MDCT scans chosen from clinical routine two times and marked all detected pulmonary nodules: first with CAD as CR (display of CAD results immediately in the reading session) and later (median 14 weeks) with CAD as SR (display of CAD markers after completion of first reading without CAD). A Siemens LungCAD prototype was used. Sensitivities for detection of nodules and reading times were recorded. Sensitivity of reading with CAD as SR was significantly higher than reading without CAD (p < 0.001) and CAD as CR (p < 0.001). For nodule size of 1.75 mm or above no significant sensitivity difference between CAD as CR and reading without CAD was observed; e.g., for nodules above 4 mm sensitivity was 68% without CAD, 68% with CAD as CR (p = 0.45) and 75% with CAD as SR (p < 0.001). Reading time was significantly shorter for CR (274 s) compared to reading without CAD (294 s; p = 0.04) and SR (337 s; p < 0.001). In our study CAD could either speed up reading of chest CT cases for pulmonary nodules without relevant loss of sensitivity when used as CR, or it increased sensitivity at the cost of longer reading times when used as SR.


Assuntos
Inteligência Artificial , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Análise e Desempenho de Tarefas , Tomografia Computadorizada por Raios X/métodos , Reações Falso-Positivas , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Tomografia Computadorizada por Raios X/instrumentação
14.
Eur Radiol ; 16(5): 1131-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16450084

RESUMO

For optimal image fusion between CT and F-18-FDG-PET, the acquisition of CT images is performed in mild expiratory suspension, which might compromise the detection of lung metastases. This study aimed at evaluating the influence of expiration on the detection of solitary pulmonary nodules (SPN) and at assessing if additional inspiratory low-dose CT (I-LDCT) of the chest can improve the detection of potential lung metastases performing whole-body 16-channel PET-CT. Sixty-six patients with malignant tumors underwent PET-CT: contrast-enhanced CT was acquired during mild expiration and was used for fusion with PET images; additionally, chest I-LDCT was performed at deep inspiration. Two radiologists reported all SPN detected at I-LDCT and the expiratory CT scan independently. Overall, 53% of 128 SPN (mean: 3.8+/-0.2 mm) were detected at both respiratory states: 51 SPN only at I-LDCT, and 9 nodules only at expiratory CT. Of the SPN, 117/128 were classified as certain; 45 of those were additionally detected at I-LDCT, and 6 nodules at expiratory CT. A 100% detection rate was reached in SPN >4 mm at I-LDCT versus >8 mm at expiratory CT (all P<0.001). Additional I-LDCT of the chest significantly improves the detection of SPN at whole-body F-18-FDG-PET-CT and thus is recommended as part of the standard protocol for oncological patients.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Imagem Corporal Total , Adulto , Idoso , Meios de Contraste/administração & dosagem , Expiração , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Inalação , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Doses de Radiação , Nódulo Pulmonar Solitário/patologia , Tórax/diagnóstico por imagem
15.
Eur Radiol ; 16(7): 1614-20, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16369826

RESUMO

The fusion of computed tomography (CT) and positron emission tomography (PET) may improve diagnostic accuracy, but is limited by different breathing protocols. This study aimed at quantifying respiration-induced alignment errors. PET-CT was acquired in 24 patients. Contrast-enhanced whole-body CT was obtained in a single breath hold in the expiratory state of a normal breathing cycle. An inspiratory low-dose CT of the thorax was acquired in the same session, and comparison of the two CT scans was used to assess the potential mismatch of PET and CT fusion. The largest craniocaudal expansion was found in the area of the diaphragm. A considerable sagittal expansion was found in the anterior parts of the lungs. Central tracheo-bronchial structures were displaced during inspiration mainly in the anterior and caudal directions. The craniocaudal shift of central structures showed a linear correlation with the diaphragmatic expansion, whereas the sagittal shift correlated with the sagittal pleural expansion. There was, however, no correlation between craniocaudal and sagittal respiratory motion. Alignment errors are most severe in the base of the lung, but central structures are affected, too. Understanding of the main vectors of respiratory motion may help in image interpretation when PET and CT are acquired separately.


Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/fisiopatologia , Movimento , Tomografia por Emissão de Pósitrons/métodos , Mecânica Respiratória , Tórax/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatística como Assunto , Técnica de Subtração
17.
Rofo ; 173(4): 373-8, 2001 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-11367849

RESUMO

PURPOSE: To evaluate the image quality and radiation exposure of different spiral CT scanning parameters for routine staging examination of the abdomen in oncologic patients using a multi-slice CT scanner. METHODS/MATERIALS: Examination of 40 patients in 4 groups on a multi-slice CT scanner (Somatom VolumeZoom, Siemens AG, Forchheim). Functional detector width (4 x 2.5, 4 x 5 mm) and pitch (table feed in relation to collimated slice width) were varied (3 and 5). Tube voltage (120 kV), effective tube current (160 mAs), slice-thickness (6 mm), increment (4 mm), kernel (B 30), and contrast injection parameters were kept constant. Axial images were assessed by three radiologists regarding delineation of anatomic structures, artifacts, and overall image quality. RESULTS: Significantly reduced image quality especially due to artifacts was observed using a 5 mm detector configuration with a pitch of 5 (scan time 9 sec). Image quality was rated best for a 2.5 mm detector configuration with a pitch of 3 and a scan time of 28 sec. The effective dose was independent of the pitch. However, the mean effective dose was 9% higher using the smaller detector configuration (9.9 mSv vs 10.9 mSv). CONCLUSIONS: For routine staging CT of the abdomen use of a 4 x 2.5 mm detector configuration with a pitch between 3 and 5 is recommended. A 4 x 5 mm detector configuration using overlapping data acquisition can also be recommended, but additional thin slice reformations are not possible.


Assuntos
Neoplasias Abdominais/diagnóstico por imagem , Radiografia Abdominal , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Rofo ; 173(3): 211-7, 2001 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-11293862

RESUMO

PURPOSE: To evaluate left ventricular (LV) myocardial function in ten patients with coronary artery disease (CAD) preoperatively and 6 months after coronary bypass grafting (CABG) by cardiac MRI. MATERIAL AND METHODS: Ten patients (mean 65.2 +/- 5.9 years) with angiographically proven CAD and an indication for elective CABG underwent prospective evaluation of global LV function and regional wall motion by Cine-MRI at rest using a multiphase FLASH-2D sequence following regions of interest (ROI)-defined diagnostics of regional myocardial wall motion by means of levocardiography. Within the ROIs a total of 613 LV myocardial segments were analyzed preceding and following surgical revascularization. Results were compared with the data of 10 healthy volunteers. RESULTS: Preoperatively, patients showed reduced stroke volume and ejection fraction compared with volunteers (p < 0.01). Enddiastolic wall thickness (EDWT) and systolic wall thickening (SWT) were significantly lower in the patients (p < 0.01). Based on preoperative levocardiography ROI-defined myocardial segments showed a significantly lower preoperative EDWT in areas with wall motion abnormalities (7.4 +/- 2.5 mm; p < 0.01) than in normal myocardium (9.2 +/- 2.1 mm). Ejection fraction (p < 0.05), endsystolic wall thickness, and SWT (p < 0.01) improved significantly after bypass surgery. On ROI-defined analysis myocardial segments with impaired preoperative wall motion (n = 243) showed a significant increase of EDWT, ESWT and SWT (p < 0.01). CONCLUSION: In patients with CAD, cardiac MRI enables the non-invasive determination of postinfarctional LV remodeling with an increased EDWT of myocardial segments with normal regional wall motion and of the improvement in global and regional myocardial function following coronary bypass surgery.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/fisiopatologia , Doença das Coronárias/cirurgia , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda , Idoso , Angiografia Coronária , Ponte de Artéria Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Miocárdio Atordoado/diagnóstico , Período Pós-Operatório , Estudos Prospectivos , Volume Sistólico , Fatores de Tempo
19.
Eur Radiol ; 11(2): 273-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11218027

RESUMO

A case of an intraspinal growing desmoplastic fibroma of the thoracic spine (T9-T11) is reported. Desmoplastic fibroma is a rare tumor of connective tissue that shows a locally infiltrative and destructive growth. An affection of the thoracic spine is an extremely rare manifestation. Preoperative CT documents the extent of osseous destruction and tumor associated cortical erosion. In central tumor areas an inhomogeneous, intermediate to low signal is demonstrated by MRI using T1- and T2-weighted spin-echo and turbo-spin-echo sequences. Contrast-enhanced MRI shows marked enhancement in peripheral areas depicting the extraosseous and intramedullary extension.


Assuntos
Imagem Ecoplanar , Fibroma Desmoplásico/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Vértebras Torácicas , Tomografia Computadorizada por Raios X , Adolescente , Biópsia , Diagnóstico Diferencial , Feminino , Fibroma Desmoplásico/cirurgia , Fíbula/transplante , Humanos , Fusão Vertebral/métodos , Neoplasias da Coluna Vertebral/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia
20.
J Comput Assist Tomogr ; 24(5): 688-90, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11045686

RESUMO

We report a case of a 43-year-old male patient with an atypical nonobstructive hypertrophic cardiomyopathy and a calcified left ventricular thrombus, and present results of multislice computed tomography (MSCT) using retrospective electrocardiograph gating, which is a new modality in cardiac imaging. Obtaining virtually motion-free images with a temporal resolution of 250 ms in an optimized heart scan MSCT allows functional imaging with evaluation of impaired systolic and diastolic left ventricular wall motion.


Assuntos
Calcinose/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Calcinose/complicações , Cardiomiopatia Hipertrófica/complicações , Cardiopatias/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Trombose/complicações
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