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1.
ESMO Open ; 9(1): 102219, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38194881

RESUMO

BACKGROUND: Despite the prognostic relevance of cachexia in pancreatic cancer, individual body composition has not been routinely integrated into treatment planning. In this multicenter study, we investigated the prognostic value of sarcopenia and myosteatosis automatically extracted from routine computed tomography (CT) scans of patients with advanced pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: We retrospectively analyzed clinical imaging data of 601 patients from three German cancer centers. We applied a deep learning approach to assess sarcopenia by the abdominal muscle-to-bone ratio (MBR) and myosteatosis by the ratio of abdominal inter- and intramuscular fat to muscle volume. In the pooled cohort, univariable and multivariable analyses were carried out to analyze the association between body composition markers and overall survival (OS). We analyzed the relationship between body composition markers and laboratory values during the first year of therapy in a subgroup using linear regression analysis adjusted for age, sex, and American Joint Committee on Cancer (AJCC) stage. RESULTS: Deep learning-derived MBR [hazard ratio (HR) 0.60, 95% confidence interval (CI) 0.47-0.77, P < 0.005] and myosteatosis (HR 3.73, 95% CI 1.66-8.39, P < 0.005) were significantly associated with OS in univariable analysis. In multivariable analysis, MBR (P = 0.019) and myosteatosis (P = 0.02) were associated with OS independent of age, sex, and AJCC stage. In a subgroup, MBR and myosteatosis were associated with albumin and C-reactive protein levels after initiation of therapy. Additionally, MBR was also associated with hemoglobin and total protein levels. CONCLUSIONS: Our work demonstrates that deep learning can be applied across cancer centers to automatically assess sarcopenia and myosteatosis from routine CT scans. We highlight the prognostic role of our proposed markers and show a strong relationship with protein levels, inflammation, and anemia. In clinical practice, automated body composition analysis holds the potential to further personalize cancer treatment.


Assuntos
Aprendizado Profundo , Neoplasias Pancreáticas , Sarcopenia , Humanos , Prognóstico , Sarcopenia/complicações , Músculo Esquelético/patologia , Estudos Retrospectivos , Composição Corporal , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/patologia
2.
Int J Med Sci ; 18(13): 2905-2909, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220317

RESUMO

Objective: To investigate the association of a wide QRS-T angle on the surface ECG and late gadolinium enhancement on contrast-enhanced cardiovascular magnetic (CMR) imaging in patients with clinically suspected myocarditis. Background: Diagnosis and risk stratification in patients with suspected myocarditis is particularly challenging due to a great spectrum of clinical presentations. Late gadolinium enhancement (LGE) visualizes myocardial necrosis and fibrosis in patients with biopsy-proven myocarditis. The presence or absence of late gadolinium enhancements in these patients is prognostically meaningful. The QRS-T angle from the surface ECG, on the other hand, may serve as a simple and easily available risk marker in suspected myocarditis. Methods: We enrolled 97 consecutive patients that were referred to CMR imaging for a clinical suspicion of myocarditis. All patients obtained a standardized digital 12-lead ECG for the calculation of the QRS-T angle and underwent contrast-enhanced CMR imaging. Patients were divided into two groups according to the absence or presence of LGE on CMR. Results: 78 of 97 patients with suspected myocarditis had LGE on CMR. Patients with LGE had wider QRS-T angles as compared to the patient group without LGE (53.95-47.5 vs. 26.2-21.2; p<0.001). The sensivity, specificity, negative predictive value and positive predictive value for a QRS-T angle above 90 degrees for LGE positive myocarditis were 16.5%, 100%, 24.7%, and 100%, respectively. Conclusion: A wide QRS-T angle of 90 degrees or more is linked to myocardial fibrosis or necrosis (late gadolinium enhancement) in patients with suspected myocarditis.


Assuntos
Coração/diagnóstico por imagem , Miocardite/diagnóstico , Miocárdio/patologia , Adulto , Idoso , Biópsia , Meios de Contraste/administração & dosagem , Eletrocardiografia , Feminino , Fibrose , Gadolínio/administração & dosagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Necrose/diagnóstico , Necrose/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco
3.
Int J Med Sci ; 17(15): 2264-2268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922190

RESUMO

Background: The QRS-T angle from the surface EKG is a promising prognostic marker in patients with coronary artery disease. Cardiovascular magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) offers high resolution imaging of myocardial damage. We investigated the association of the QRS-T angle and the extent of myocardial damage as assessed by LGE in patients with acute ST-segment myocardial infarction (STEMI) Methods: 169 patients with STEMI obtained a standardized digital 12-lead EKG on admission for the calculation of the QRS-T angle and underwent CMR imaging for analysis of infarct size by LGE within the first week. Patients were divided into groups: (1) abnormal QRS-T angle ≥ 90 degree and (2) QRS-T angle < 90 degree. Results: Patients with a QRS-T angle of 90 degree or more had larger infarcts (36.5±12.4 vs. 13.3±9.5; p<0.001) and lower ejection fraction (42.9±12.1% vs. 50.6±10.6%; p<0.001). Conclusion: The extent of myocardial damage as measured by the gold standard LGE is associated with a larger QRS-T angle calculated from the surface EKG.


Assuntos
Eletrocardiografia , Imageamento por Ressonância Magnética , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Idoso , Meios de Contraste/administração & dosagem , Feminino , Gadolínio/administração & dosagem , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
4.
Magn Reson Med ; 80(1): 239-247, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29194732

RESUMO

PURPOSE: A prerequisite for cardiac MR (CMR) imaging is adequate synchronization of image acquisition with the cardiac cycle. Electrocardiogram triggering may be hampered by electromagnetic interferences at high field strength. The purpose of this work is to evaluate the feasibility of Doppler ultrasound triggering for CMR image synchronization at 7T ultra-high-field MRI. METHODS: A custom-built Doppler ultrasound (DUS) trigger device was developed. Magnetic resonance compatibility was evaluated using E- and H-field probes and flip angle maps prior to the study. Cardiac MR was performed at 7T in 13 healthy subjects using DUS and pulse oximetry for triggering. For validation of the trigger signal, the electrocardiogram, pulse, and DUS signals were compared outside of the MR room. Breath-hold cine fast low-angle-shot sequences were acquired in short-axis and four-chamber view. Image quality was assessed by two senior radiologists and by measurement of endocardial blurring. RESULTS: The maximal change in E- and H-field distributions with and without transducer was 5%. No interferences were observed between DUS and MRI in the B1 maps and during CMR imaging. Validation of the DUS trigger signal resulted in a high correlation to the electrocardiographic signal of r = 0.99. Analysis of image and trigger quality revealed no significant differences. CONCLUSION: Doppler ultrasound was applied as a new trigger method in CMR at 7T. The transmission line and transducer were locally approved as 7T MR conditional, and were successfully tested for image synchronization at 7T. In the future, this method needs to be evaluated in a larger patient population. Magn Reson Med 80:239-247, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Assuntos
Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ultrassonografia Doppler , Adulto , Artefatos , Eletrocardiografia , Radiação Eletromagnética , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Testes de Função Cardíaca , Humanos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Masculino , Imagem Multimodal/métodos , Reprodutibilidade dos Testes , Adulto Jovem
5.
J Nucl Cardiol ; 24(3): 980-988, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-26993494

RESUMO

OBJECTIVE: Assessment of increased glucose uptake in inflammatory or malignant myocardial disease using PET/MRI relies on uptake suppression in normal myocardium. We evaluated the efficacy of a ≥24 hours high-fat, low-carbohydrate, and protein-permitted diet (HFLCPP) in combination with unfractionated heparin for suppression of "physiologic" myocardial glucose uptake. METHODS: PET/MRI was successfully performed in 89 patients. HFLCPP was started ≥24 hours prior to PET/MRI. All patients received i.v. injection of unfractionated heparin (50 IU·kg-1) 15 minutes prior to FDG administration. Left ventricular FDG uptake was visually evaluated by two readers. Diffuse myocardial uptake exceeding liver uptake, isolated uptake in the lateral wall, or diffuse uptake in the entire circumference of the heart base were defined as failed suppression. Homogeneous myocardial uptake below liver uptake with/without focal uptake was defined as successful suppression. RESULTS: Success rate was 84%. Suppression was unsuccessful in 14 patients. No significant influence of gender (P = .40) or age (P = .21) was found. However, insufficient suppression was more common in patients younger than 45 years (20% vs 7%). PET/MR imaging completion rate was >97%. CONCLUSION: A HFLCPP diet in combination with unfractionated heparin was successfully implemented for cardiac PET/MRI and resulted in a sufficient suppression of myocardial FDG uptake in 84% of patients.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Dieta com Restrição de Carboidratos/métodos , Proteínas Alimentares/administração & dosagem , Fluordesoxiglucose F18/farmacocinética , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Miocárdio/metabolismo , Adulto , Jejum , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Eur Radiol ; 26(11): 4072-4079, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26943131

RESUMO

OBJECTIVES: To assess the impact of the scout view orientation on radiation exposure and image quality in thoracoabdominal CT, when automated tube voltage selection (ATVS) and automated tube current modulation (ATCM) are used in combination with scan planning on a single scout view. METHODS: Fifty patients underwent two thoracoabdominal CT examinations, one planned on an anteroposterior scout view, one planned on a lateral scout view. Both examinations included contrast-enhanced imaging of chest (CH) and abdomen (AB) and non-contrast-enhanced imaging of the liver (LI). For all examinations the same imaging protocol was used on the same dual-source CT scanner. The radiation exposure was recorded and objective as well as visual image quality was assessed for all examinations. RESULTS: The median dose-length product was significantly lower in scans planned on a lateral scout view (CH: 179 vs. 218 mGy*cm, LI: 148 vs. 178 mGy*cm, AB: 324 vs. 370 mGy*cm, p < 0.0001). Objective image quality was marginal lower in scans planned on a lateral scout view, whereas the visual image quality was rated as equal. CONCLUSION: At the tested radiation doses, the orientation of the scout view has a significant impact on the radiation exposure but no clinically relevant impact on the image quality. KEY POINTS: • The scout view orientation has a significant impact on the radiation exposure. • The scout view orientation has no clinically relevant impact on image quality. • A lateral scout view should be preferred with regard to radiation exposure.


Assuntos
Doses de Radiação , Exposição à Radiação/estatística & dados numéricos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Abdome/diagnóstico por imagem , Feminino , Humanos , Fígado , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal/normas , Radiografia Torácica/normas , Reprodutibilidade dos Testes , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas
8.
Rofo ; 186(2): 166-72, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24081784

RESUMO

PURPOSE: To assess the diagnostic accuracy of T2 mapping for the detection of myocardial edema in acute myocardial infarction (AMI), and to compare this diagnostic accuracy with that of the current standard for myocardial edema imaging, which is T2w dark-blood TSE imaging. MATERIALS AND METHODS: 29 patients with AMI were examined at 1.5 T. For the visualization of myocardial edema, T2 maps, calculated from three T2w SSFP images, and T2w dark-blood TSE images were acquired in standard short- and long-axis views. Cine SSFP images were acquired for the analysis of left ventricular (LV) function and late gadolinium enhancement images (LGE) for the visualization of myocardial necrosis. The T2 maps as well as the T2w dark-blood TSE images were evaluated twice independently from the cine SSFP and LGE images. The presence or absence of myocardial edema was rated visually for each LV segment. As the standard of reference, the infarct zone was defined based on the cine SSFP and the LGE images. RESULTS: In this segment-based analysis, T2 mapping showed a sensitivity of 82 % and a specificity of 94 % for the detection of edema in the infarct zone. T2w dark-blood TSE imaging revealed a sensitivity of 50 % and a specificity of 98 %. T2 mapping showed a higher intra-rater agreement compared to T2w dark-blood TSE imaging (κ: 0.87 vs. 0.76). CONCLUSIONS: T2 mapping allows for the visualization of myocardial edema in AMI with a high sensitivity and specificity, and features better diagnostic accuracy in terms of a higher sensitivity compared to T2w dark-blood TSE imaging. Citation Format: • Naßenstein K, Nensa F, Schlosser T et al. Cardiac MRI: T2-Mapping Versus T2-Weighted Dark-Blood TSE Imaging for Myocardial Edema Visualization in Acute Myocardial Infarction. Fortschr Röntgenstr 2014; 186: 166 - 172.


Assuntos
Edema Cardíaco/etiologia , Edema Cardíaco/patologia , Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Doença Aguda , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Herz ; 39(7): 828-31, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-23978942

RESUMO

Although it is well known from pathological studies that intramyocardial fat deposition frequently occurs after left ventricular myocardial infarction, a left ventricular fat deposition is rarely diagnosed in the clinical routine. We report the case of extensive fat deposition in the left ventricular myocardium which was detected by routine cardiac magnetic resonance imaging.


Assuntos
Tecido Adiposo/patologia , Ventrículos do Coração/patologia , Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologia , Adiposidade , Idoso de 80 Anos ou mais , Humanos , Masculino
10.
Rofo ; 183(10): 933-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21863535

RESUMO

PURPOSE: An increased normalized gadolinium accumulation (NGA) in the myocardium during early washout has been used for the diagnosis of acute myocarditis (AM). Due to the fact that the pharmacokinetics of contrast agents are complex, time-related changes in NGA after contrast injection are likely. Because knowledge about time-related changes of NGA may improve the diagnostic accuracy of MR, our study aimed to estimate the time course of NGA after contrast injection in patients as well as in healthy volunteers. MATERIALS AND METHODS: An ECG-triggered inversion recovery SSFP sequence with incrementally increasing inversion times was repetitively acquired over the 15 minutes after injection of 0.2 Gd-DTPA per kg body weight in a 4-chamber view in 15 patients with AM and 20 volunteers. The T 1relaxation times and the longitudinal relaxation rates (R1) of the myocardium and skeletal musculature were calculated for each point in time after contrast injection. The time course of NGA was estimated based on the linear relationship between R1 and tissue Gd concentration. RESULTS: NGA decreased over time in the form of a negative power function in patients with AM and in healthy controls. NGA in AM tended to be higher than in controls (p > 0.05). CONCLUSION: NGA rapidly changes after contrast injection, which must be considered when measuring NGA. Although we observed a trend towards higher NGA values in patients with AM with a maximum difference one minute after contrast injection, NGA did not allow us to differentiate patients with AM from healthy volunteers, because the observed differences did not reach a level of significance.


Assuntos
Meios de Contraste/farmacocinética , Gadolínio DTPA/farmacocinética , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Miocardite/diagnóstico , Doença Aguda , Adulto , Técnicas de Imagem de Sincronização Cardíaca , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Contração Miocárdica/fisiologia , Miocárdio/patologia , Valores de Referência , Sensibilidade e Especificidade
11.
Rofo ; 183(3): 233-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21080303

RESUMO

PURPOSE: To evaluate the impact of the reconstruction interval on coronary calcium score and cardiac risk stratification using dual-source computed tomography (DSCT). MATERIALS AND METHODS: DSCT coronary calcium scoring was performed in 61 consecutive patients, and five data sets per patient were reconstructed within diastole (50 - 70 % of the R-R interval). The Agatston score, volumetric score and the relative variability were assessed for all reconstructions. To assess the individual cardiovascular risk, patients were assigned to risk groups based on age and gender-matched percentile ranks. RESULTS: The mean Agatston score was 184.8 ± 377.9 (relative variability 47 % ± 52 %). The mean volumetric score was 164.4 ± 310.1 (relative variability 49 % ± 58 %). There was a negative correlation between the total Agatston score and the relative variability (r = -0.37; p < 0.01). Depending on the reconstruction interval used, 18 predominantly young patients were assigned to more than one risk group. CONCLUSION: Despite the increased temporal resolution of DSCT examinations, the Agatston and volumetric scores depend on the reconstruction time within the cardiac cycle. The fact that the greatest relative variability for both the Agatston score and the volumetric score was found in young patients with small amounts of coronary calcium may result in different treatment strategies for young patients depending on the reconstruction used. Therefore, more accurate risk stratification may require the analysis of multiple reconstruction intervals.


Assuntos
Calcinose/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Diástole/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade
12.
Rofo ; 182(9): 780-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20563959

RESUMO

PURPOSE: Guide-point modeling (GPM) enables reliable and time-efficient assessment of left ventricular (LV) volumes when using sequences that allow acquisition of short- and long-axis scans within a single breath-hold. Slice misalignment may influence GPM analysis of standard multi-breath-hold images due to image acquisition in different breath-holds. Thus, our study aimed to assess if such an approach allows for reliable volumetric calculations in the clinical routine. MATERIALS AND METHODS: 52 patients were examined on a 1.5 T scanner with multi-breath-hold acquisitions on the standard short- and long-axis using an SSFP (TR 3 ms, TE 1.5 ms, FA 60 degrees ) sequence and a TPAT accelerated SSFP (TR 4.6 msec, TE 1.1msec, FA 60 degrees , acceleration factor 3) sequence that covered the LV in 3 short- and 2 long-axis slices within a single breath-hold. For both datasets GPM was used to assess LV volumes. In addition, LV parameters were calculated by applying the summation of slices (SoS) approach (standard of reference) with the short-axis views of the multi-breath-hold dataset. RESULTS: The post-processing times were shorter with both GPM approaches (both, p < 0.001). No significant difference between the 3 methods for the calculation of the ejection fraction was observed. However, end-diastolic, end-systolic and stroke volumes yielded higher results than the standard of reference if the GPM technique was employed. Excellent correlations were observed for all volumetric parameters derived from both GPM evaluations (all r > 0.97). CONCLUSION: Cine short- and long-axis images that had been acquired in different breath-holds can be reliably evaluated by the GPM approach.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Respiração , Volume Sistólico/fisiologia , Tomografia Computadorizada por Raios X/métodos , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Simulação por Computador , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Software , Adulto Jovem
14.
Rofo ; 181(7): 669-74, 2009 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-19353485

RESUMO

PURPOSE: Microvascular obstruction (MO) and the extent of infarction are important prognostic factors in acute myocardial infarction. Our study aimed to investigate the effect of the time interval between contrast administration and image acquisition on the quantification of microvascular obstruction and myocardial infarction. MATERIALS AND METHODS: 50 consecutive patients with acute myocardial infarction (40 male, mean age 58.1 +/- 11.7 years) treated by percutaneous coronary revascularization resulting in a grade 3 flow according to the thrombolysis in myocardial infarction flow classification were examined on a 1.5 T MR scanner within the first 5 days after infarction. 2, 5, 10, and 20 minutes after I.V. administration of 0.2 mmol/kg per kg body weight of Gadodiamid (Omniscan), GE Healthcare Buchler, Germany), a single shot IR-SSFP sequence (TR 2.4 ms, TE 1.08 ms, TI 180 - 280 ms, FA 50 degrees) covering the entire left ventricle was acquired. Areas of MO and myocardial infarction were measured for all times after contrast injection (p. i.). RESULTS: MO was detected in 32 of 50 patients two minutes p. i., while 23 patients showed evidence of MO (p = 0.002) 20 min. p. i. In all patients with MO, the extent of MO decreased over time (7.4 +/- 9.0 % of the LV myocardium 2 min. p. i. vs. 2.4 +/- 4.6 % 20 min. p. i. p < 0.0001). The area of myocardial infarction increased from 13.9 +/- 13.5 % 2 min. p. i. to 18.6 +/- 14.2 % 10 min. p. i. (p < 0.0001), and then remained unchanged (18.7 +/- 14.3 % at 20 min. p = 0.57). CONCLUSION: Our study shows that the time delay between contrast media injection and image acquisition has a significant impact on the delimitable extent of MO and infarct size.


Assuntos
Angiografia Coronária/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos , Microcirculação , Infarto do Miocárdio/diagnóstico , Fenômeno de não Refluxo/diagnóstico , Adulto , Idoso , Angioplastia Coronária com Balão , Meios de Contraste/administração & dosagem , Meios de Contraste/farmacocinética , Feminino , Gadolínio DTPA/farmacocinética , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miocárdio/patologia , Terapia Trombolítica , Resultado do Tratamento
15.
Acta Radiol ; 50(4): 406-11, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19308763

RESUMO

BACKGROUND: Several studies have demonstrated that the administration of contrast agents is advantageous in magnetic resonance coronary angiography (MRCA). PURPOSE: To compare a non-contrast-enhanced steady-state free-precession (SSFP) with a contrast-enhanced inversion recovery spoiled gradient-echo (IR-GE) sequence using two different contrast agents for MRCA. MATERIAL AND METHODS: Eight healthy volunteers were examined on a 1.5T MR scanner. For non-contrast-enhanced MRCA, a breath-hold three-dimensional (3D) SSFP sequence (repetition/echo time [TR/TE] 3.9/1.7 ms, flip angle [FA] 65 degrees) was used. Contrast-enhanced MRCA was performed repetitively in two imaging sessions over 30 min after injection of 0.2 mmol/kg body weight gadobenate dimeglumine (Gd-BOPTA) or gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) using a breath-hold 3D IR-GE sequence (TR/TE 4.1/1.7 ms, FA 15 degrees). The signal-to-noise ratios (SNR) of the coronary arteries, as well as the contrast-to-noise ratios (CNR) between coronary arteries and perivascular tissue, were calculated for all images. Blood T (1) values were repetitively estimated over 30 min using an SSFP sequence with incrementally increasing inversion times (TR/TE 2.4/1.0 ms, FA 50 degrees). RESULTS: Gd-BOPTA-enhanced images showed significantly (P<0.05) higher SNR and CNR compared to Gd-DTPA-enhanced images for all times after contrast injection (SNR: 1 min post injection [PI] 26.4+/-4.2 vs. 16.2+/-3.1; CNR: 1 min PI 21.4+/-3.7 vs. 13.2+/-2.6). Compared to the SSFP images, the Gd-BOPTA-enhanced images showed higher CNR values for all times after injection (1 min PI 21.4+/-3.7 vs. 13.8+/-5.5; P<0.05), whereas the Gd-DTPA-enhanced images did not (1 min PI 13.2+/-2.6 vs. 13.8+/-5.5; P>0.05). Blood T (1) estimates were not significantly different for either agent 1 min after administration (P>0.05), but they were significantly lower for Gd-BOPTA (P<0.05) from 7 to 25 min after injection. CONCLUSION: Compared to non-contrast-enhanced SSFP images, only Gd-BOPTA-enhanced images show a significantly improved contrast between the coronary arteries and the surrounding tissue.


Assuntos
Meios de Contraste , Angiografia Coronária , Gadolínio DTPA , Angiografia por Ressonância Magnética , Meglumina/análogos & derivados , Compostos Organometálicos , Adulto , Gadolínio , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino
16.
Rofo ; 181(5): 472-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19241322

RESUMO

PURPOSE: To assess the prevalence and pattern of myocardial late gadolinium enhancement (LGE) and its functional impact on patients with left ventricular hypertrophy caused by aortic valve stenosis. MATERIALS AND METHODS: Cardiac magnetic resonance imaging of 40 patients (17 female, 23 male, mean age: 76.6 +/- 22.5 years) with known aortic valve stenosis (mean aortic valve area: 89.8 +/- 19.2 mm(2)) and without coronary artery disease was performed at 1.5 T using steady-state free precession sequences for aortic valve planimetry and for the assessment of left ventricular (LV) volumes and mass. Ten to 15 minutes after injection of 0.2 mmol Gd-DTPA per kilogram body weight, inversion-recovery prepared spoiled gradient echo images were acquired in standard long and short axis views to detect areas of LGE. RESULTS: LGE was observed in 32.5 % (13/40) of our patients. LGE was mainly located in the basal septal and inferior LV segments, and showed a non-ischemic pattern with sparing of the subendocardial region. Patients with LGE showed lower LV ejection fractions (55.5 +/- 13.8 % vs. 69.1 +/- 10.7 %, p = 0.0014), higher LV end-systolic volumes (59.8 +/- 33.3 ml vs. 36.6 +/- 16.0 ml, p = 0.0048), and LV masses (211.0 +/- 13.8 vs. 157.9 +/- 37.5 g, p = 0.0002) compared to patients without LGE. CONCLUSION: LGE is frequent in patients with hypertrophic left ventricles due to aortic valve stenosis and is associated with worse LV function.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Meios de Contraste/administração & dosagem , Gadolínio DTPA , Hipertrofia Ventricular Esquerda/diagnóstico , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Volume Cardíaco/fisiologia , Endocárdio/patologia , Endocárdio/fisiopatologia , Fibrose Endomiocárdica/diagnóstico , Feminino , Implante de Prótese de Valva Cardíaca , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/cirurgia , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Prognóstico , Volume Sistólico/fisiologia , Função Ventricular Esquerda , Adulto Jovem
17.
Rofo ; 180(12): 1054-60, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19009498

RESUMO

PURPOSE: Our study aimed to assess the prevalence and pattern of late gadolinium enhancement (LGE) as an in vivo correlate of myocardial fibrosis in cardiac asymptomatic patients with systemic sclerosis (SSc). MATERIALS AND METHODS: Cardiac magnetic resonance imaging was successfully performed in 34 patients (30 female, 4 male, mean age of 54 +/- 14 years) with proven SSc and in controls with matching age, sex and cardiovascular risk factors. All examinations were performed on a 1.5 T MR system (Avanto, Siemens, Germany). 2D inversion recovery spoiled gradient echo images (TR 8.0 msec, TE 4.0 msec, TI 180 - 240 msec, FA 20 degrees, slice thickness 8 mm, in-plane resolution 1.2 x 1.2 mm (2)) were acquired 10 to 15 min after injection of 0.2 mmol Gd-DTPA per kg body weight to detect myocardial LGE. RESULTS: Poorly defined, patchy as well as well-defined focal areas of LGE were detected predominantly in the mid-myocardial layer of the basal left ventricular segments in 5 of 34 (15 %) SSc patients. A focal area of LGE was observed within the apical septum in one control (3 %, p > 0.05). LGE was observed in a total of 15 segments of the SSc patients and in 1 segment of the controls (p < 0.005). CONCLUSION: Our results revealed a significantly higher number of LGE positive segments in patients with SSc compared to matched controls, and demonstrate the ability of contrast-enhanced MRI to detect myocardial fibrosis, the hallmark of scleroderma heart disease, in-vivo.


Assuntos
Meios de Contraste , Fibrose Endomiocárdica/diagnóstico , Gadolínio DTPA , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Escleroderma Sistêmico/diagnóstico , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Fibrose Endomiocárdica/epidemiologia , Feminino , Septos Cardíacos/patologia , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/epidemiologia , Escleroderma Sistêmico/epidemiologia
18.
Acta Radiol ; 48(10): 1101-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17963088

RESUMO

BACKGROUND: Identification of primary tumor in patients with cervical lymph node metastasis of unknown primary (MUO) has a great impact on therapy approach and potentially on patient prognosis. PURPOSE: To assess the diagnostic accuracy of combined positron emission tomography(PET)/computer tomography (CT) for primary tumor detection in cervical metastases of unknown origin compared to PET, CT, and PET+CT side-by-side evaluation. MATERIAL AND METHODS: 39 consecutive patients (eight women, 31 men; mean age 59.9 ± 11.2 years) with MUO were enrolled in this study. PET/CT images were obtained 1 hour after injection of 350 MBq of fluorodeoxyglucose. Oral and intravenous contrast agents were administered in all patients to ensure diagnostic CT data. Fused PET/CT data were evaluated for primary tumor detection. Diagnostic accuracy was calculated and compared with CT alone, PET alone, and side-by-side PET+CT evaluation.Statistical analysis of differences in diagnostic performance between the different imaging procedures was based on the McNemar test. RESULTS: Fused PET/CT depicted the primary tumor in 11 of 39 (28%) patients. In 28(72%) patients, the primary tumor remained occult. CT revealed the primary in five(13%), PET alone in 10 (26%), and side-by-side evaluation of PET+CT in 10 (26%) of 39 patients. Statistical analysis showed no significant differences between the imaging modalities. CONCLUSION: PET, side-by-side PET+CT, and PET/CT revealed similar detection rates for primary tumors in cervical MUO patients. Therefore, cervical metastases of an unknown primary may be assessed with either of these imaging modalities. Detection rates with CT were substantially lower. Thus, inclusion of functional data for assessment of cervical MUO patients must be recommended.


Assuntos
Metástase Linfática/diagnóstico por imagem , Neoplasias Primárias Desconhecidas/diagnóstico por imagem , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço , Neoplasias Primárias Desconhecidas/patologia , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
19.
Eur J Med Res ; 12(5): 185-90, 2007 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-17513188

RESUMO

OBJECTIVE: To characterize cardiac abnormalities in HIV+ patients with increased serum B-type natiuretic peptide (BNP) by contrast-enhanced cardiac magnetic resonance imaging (MRI). DESIGN: Non-blinded prospective consecutive cohort evaluation. METHODS: More than 400 HIV+ patients were screened for potential BNP alterations. 16 met the inclusion criteria of elevated BNP levels and 12 patients could finally be enrolled. MRI analysis comprised function, oedema and late enhancement sequences. RESULTS: Patients exhibited a median serum BNP level of 249 pg/ml. Based on MRI, diagnosis of left ventricular hypertrophy (n = 3), myocarditis (n = 2), chronic myocardial infarction (n = 2), dilated cardiomyopathy (n=1) and right ventricular failure (n = 1) was made. CONCLUSIONS: Although no specific MR pattern was found, MR allowed characterization of the underlying cardiac pathologies in 82% of HIV+ patients with elevated BNP levels.


Assuntos
Infecções por HIV/complicações , Cardiopatias/diagnóstico , Cardiopatias/virologia , Peptídeo Natriurético Encefálico/sangue , Infecções por HIV/sangue , Cardiopatias/sangue , Humanos , Imageamento por Ressonância Magnética , Intensificação de Imagem Radiográfica
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