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1.
Phys Med ; 122: 103378, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797026

RESUMO

PURPOSE: To compare the breast imaging performance of a clinical whole-body photon-counting CT (PCCT) to that of a dedicated breast CT (BCT) to determine the image quality of opportunistic breast examinations in clinical PCCT. MATERIALS AND METHODS: To quantify image quality for breast cancer applications, acquisitions of a breast phantom including representations of calcifications, fibers, and masses were performed using a clinical PCCT and a dedicated BCT. When imaging with the PCCT, the phantom was also combined with a thorax phantom to simulate realistic patient positioning, while only the breast phantom was imaged in the BCT. Images in BCT were acquired at 7.0 mGy (CTDI16cm) and using 2.6 mGy-25.0 mGy in the PCCT. Spatial resolution between the BCT and PCCT images was matched and data were reconstructed using the default methods of each system. The dose-normalized contrast-to-noise ratio (CNRD) of masses and the structural visibility of fibers and calcifications were evaluated as figures of merit for all reconstructions. RESULTS: CNRD between masses and background was 0.56 mGy-½, on average with BCT and varied between 0.39 mGy-½ to 1.46 mGy-½ with PCCT over all dose levels, phantom configurations, and reconstruction algorithms. Calcifications down to a size of 0.29 mm and fibers down to a size of 0.23 mm could be reliably identified in the images of both systems. CONCLUSIONS: Clinical PCCT provides an image quality superior to that obtained with BCT in terms of CNRD and allows for the identification of calcifications and fibers at comparable dose levels.

2.
Prenat Diagn ; 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797992

RESUMO

OBJECTIVE: We aim to provide a template structured report of fetal Magnetic Resonance Imaging in congenital diaphragmatic hernia (CDH) that was locally validated by the CDH study group in Mannheim. METHODS: A selection of 50 fetal MRIs of patients with an isolated diaphragmatic hernia and associated radiology reports from five different senior radiologists from a single center resulted in a primary structured report, which was put into practice by using dedicated software. A questionnaire survey of the interdisciplinary CDH study group Mannheim was used to adapt the report to the clinical requirements. RESULTS: There was a huge variability in how deep the free text reports go into detail. The side of the hernia was named in 94% of cases. In 58%, both the lung volume and the total lung volume were reported. A comparison with the expected lung volume was reported in 66% of cases. Additional findings, such as herniated organs, were reported in 96% of cases. Overall satisfaction with the newly established structured report was high within the CDH study group with a mean of 4.7. CONCLUSIONS: The use of the structured report of this study can optimize the interdisciplinary dialog, the standardization of report content, increase report completeness and improve quality.

3.
Radiologie (Heidelb) ; 63(4): 275-283, 2023 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-36811691

RESUMO

CLINICAL/METHODOLOGICAL ISSUE: Due to active participation of children and adolescents in school sports as well as in club sports, sporting injuries in childhood are common. Because skeletal maturity is not yet complete, injury patterns in children differ from sporting injuries in adults. Knowledge of the pathophysiologic characteristics, as well as knowledge of typical injury sequelae, is of great relevance to radiologists. This review article therefore deals with common acute and chronic sporting injuries in children. STANDARD RADIOLOGICAL METHODS: Basic diagnostic imaging comprises conventional X­ray imaging in two planes. In addition, sonography, magnetic resonance imaging (MRI) and computed tomography (CT) are used. PRACTICAL RECOMMENDATIONS: Close consultation with clinical colleagues and knowledge of childhood-specific injuries help identify sports-associated trauma sequelae.


Assuntos
Traumatismos em Atletas , Esportes , Adulto , Humanos , Criança , Adolescente , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/etiologia , Imageamento por Ressonância Magnética
4.
Anaesthesist ; 67(12): 901-906, 2018 12.
Artigo em Alemão | MEDLINE | ID: mdl-30367211

RESUMO

BACKGROUND: Whole-body computed tomography (CT) is increasingly being used as the diagnostic modality of choice in patients admitted to the resuscitation room. Beyond findings related to the suspected diagnosis it often additionally reveals incidental findings. The aim of this investigation was the evaluation of these findings in patients admitted via the emergency room after suffering potential major trauma or life-threatening medical conditions. Furthermore, the number of iatrogenic injuries as well as misplaced catheters and endotracheal tubes was investigated. METHODS: All patients admitted from 1 February 2012 to 31 January 2014 via the resuscitation area of the Mannheim University Medical Center, a tertiary care hospital and level 1 trauma center, were included in this study if they had undergone a whole-body CT scan at admission. Data from 1362 patients were collected retrospectively and 197 patients were excluded because of missing data so that the final cohort consisted of 1165 patients (1038 trauma and 127 internal neurological patients). Reports from the whole-body CT scans were screened for incidental findings. These findings were then classified as either clinically relevant or not. Furthermore, the reports were checked for iatrogenic injuries as well as misplaced catheters and endotracheal tubes. RESULTS: A total of 465 incidental findings were reported in 293 patients (25.1%) of the final cohort. In the synopsis of the radiological and clinical findings, 72 were rated as clinically relevant. In one patient two relevant incidental findings were reported and one patient presented with three incidental findings. In total, relevant incidental findings could be detected in 5.8% of the study patients (68/1165). In the discharge letters and/or the radiological report 16.2% of the incidental findings rated as clinically relevant were reported to be previously known, 66.2% were reported to be unknown and 17.6% could not be unequivocally classified as known or unknown due to missing references in the discharge letters. The group of internal neurological patients were clearly older than the trauma patients (61.6 years vs. 45.5 years). The rate of relevant incidental findings in the internal neurological group was more than twice as high as in the trauma group (11.0% vs. 5.2%); however, in the relatively young trauma group 1 in 20 patients showed an incidental finding classified as clinically relevant. In 43 (3.7%) patients a total of 46 iatrogenic injuries or misplaced catheters were reported. The most common finding was a too deeply placed endotracheal tube and five transurethral catheters placed in the emergency room were found to be blocked within the urethra. CONCLUSION: In addition to the main diagnosis, clinically relevant incidental findings were reported in nearly 25% of whole-body CT scans of patients admitted to the resuscitation room. Approximately 6% of patients had incidental findings rated as clinically relevant. In the internal neurological group of patients the rate of incidental findings was doubled compared to the trauma group; however, the latter were significantly younger. Whole-body CT was also useful for diagnosing iatrogenic injuries and misplaced catheters in approximately 4% of the study patients.


Assuntos
Doença Iatrogênica , Achados Incidentais , Ressuscitação/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Ressuscitação/estatística & dados numéricos , Estudos Retrospectivos , Centros de Traumatologia
5.
Radiologe ; 54(11): 1111-22; quiz 1123-4, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-25367313

RESUMO

Urinary tract infections are the most common infectious diseases in Germany. In most cases clarification does not rely on imaging techniques other than sonography and is made mostly based on clinical symptoms. Computed tomography (CT) and magnetic resonance imaging (MRI) can be used in selected cases to find the cause and detection or exclusion of complications, e.g. recurrent or atypical and complicated courses. The method of choice for clarification of urolithiasis is CT. Using low-dose techniques, detection or exclusion of urinary stones can be achieved with a high sensitivity and specificity as well as an acceptable level of radiation exposure. Native stone CT supplies additional fundamental information that can substantially influence further therapy planning. The diagnosis of ureteral injuries is clinically and radiologically not trivial and clarification is aided by urographic contrast media. The method of CT cystography has an important role in the diagnostics of urinary bladder injuries.


Assuntos
Cistite/diagnóstico , Diagnóstico por Imagem/métodos , Bexiga Urinária/lesões , Infecções Urinárias/diagnóstico , Sistema Urinário/lesões , Humanos , Ultrassonografia , Bexiga Urinária/diagnóstico por imagem , Sistema Urinário/diagnóstico por imagem , Urografia/métodos
6.
Radiologe ; 54(12): 1221-34; quiz 1235-6, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25425104

RESUMO

In the challenging evaluation of upper urinary tract malignancies multidetector computed tomography (CT) has become the standard imaging method. Cross sectional imaging not only allows the detection and visualization of the tumor itself but also provides nodal and metastasis staging in one examination (one-stop-shop). The majority of urothelial carcinomas are located in the urinary bladder. In this case, CT and more recently magnetic resonance imaging (MRI) can also deliver decisive information regarding TNM classification. A combination of clinical, histological, morphological and functional parameters allows both risk stratification and a targeted therapy based on the individual tumor stage.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/métodos , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Humanos , Cuidados Pós-Operatórios/métodos
7.
Radiologe ; 54(2): 160-6, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24233402

RESUMO

BACKGROUND: The survey results of a previous study showed that galactography is now rarely used in Germany and newer methods are applied. The evidential value of galactography should be established and opposed to the evidential value of ultrasound (US) and magnetic resonance mammography (MRM). MATERIALS AND METHODS: A search was carried out in PubMed and Cochrane involving studies written in English or German. The level of evidence was measured according to the Oxford Centre for Evidence-based Medicine. RESULTS: A total of 19 studies were included, 14 with results on galactography, 10 on US and 5 on MRM. Almost all studies were retrospective with an evidence assigned to level 3b or lower. The results on the diagnostic values showed a very wide range. Because of very variable numbers of cases and consideration of various pathologies, the studies are only comparable to a limited extent. CONCLUSION: Galactography, US and MRM all show a weak level of evidence and no superiority of a particular method can be derived. Therefore, galactography can no longer be considered as a mandatory standard in modern multimodal imaging of the breast. Recommendations for the diagnostic work-up of pathological nipple discharge have to be included in current guidelines and must consider these facts.


Assuntos
Doenças Mamárias/diagnóstico , Glândulas Mamárias Humanas/patologia , Mamografia/métodos , Imagem Multimodal/métodos , Mamilos/patologia , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Radiologe ; 2013 Nov 15.
Artigo em Alemão | MEDLINE | ID: mdl-24233401

RESUMO

PURPOSE: Galactography has been used in cases of pathological discharge for decades. Meanwhile other methods, such as high-resolution ultrasound (US) and magnetic resonance mammography (MRM) have been established for modern multimodal breast imaging. A survey among certified German breast care centers aimed to investigate to what extent galactography is currently used and whether newer techniques in multimodal imaging are preferred. MATERIALS AND METHODS: An anonymous online survey was carried out nationwide and open to 342 radiology units in certified German breast care centers. RESULTS: A total of 177 units (52 %) participated in the survey of which 13 % generally do not provide galactography, 33 % conduct a maximum of 5 galactographies per year, 24 % conduct 6-10, 18 % 11-20, 8 % 21-50 and 5 % 51-100. Of the participants 53 % give first priority to US and prefer galactography to MRM in stepwise diagnosis and 32 % prefer MRM to galactography. Only 4 % use galactography initially. CONCLUSION: Currently galactography is no longer a mandatory standard and newer methods are preferred. The evidential value of galactography in comparison to other techniques should be established on the basis of the literature. The second part of this paper will deal with this question.

9.
Rofo ; 185(8): 726-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23900940

RESUMO

PURPOSE: To prospectively investigate the predictive value of a zero calcium score (CS) value as well as age- and sex-adjusted low-end CS percentiles for the presence of significant coronary artery stenosis in stable patients with suspected coronary artery disease (CAD). MATERIALS AND METHODS: In total, 87 consecutive stable patients with suspected CAD were prospectively enrolled in this study (33 women; 66 ± 10 years). All patients underwent non-enhanced CT for calcium scoring (CSCT) and contrast-enhanced coronary CT angiography (cCTA). Invasive coronary angiography (ICA) served as the reference standard in all patients. Diagnostic performance for the presence of significant stenosis (≥ 50% diameter) was calculated separately for CS in comparison to cCTA and ICA. RESULTS: ICA identified significant stenosis in 56/87 patients (64%). The mean CS was 571 ± 599. On a per patient based analysis, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for patients with a zero CS were 98.5%, 18.2%, 78.0% and 80.0%, respectively, compared to cCTA and 100%, 16.1%, 68.3% and 100%, respectively, compared to ICA. Low-end age- and sex-adjusted percentiles derived from asymptomatic Caucasian populations showed results comparable to a CS of zero. CONCLUSION: The prevalence of significant coronary artery stenosis is low in stable patients with suspected CAD and a CS of zero but also in patients below certain low-end age- and sex-adjusted percentile ranks. Thus, CS should be used as a gatekeeper prior to further diagnostic procedures in these patients. A CS value below certain age- and sex-adjusted percentile ranks seems to be of identical diagnostic value to a CS of zero in stable patients.


Assuntos
Calcinose/diagnóstico por imagem , Cateterismo Cardíaco/métodos , Técnicas de Imagem de Sincronização Cardíaca/métodos , Meios de Contraste/administração & dosagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Iopamidol/análogos & derivados , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Sensibilidade e Especificidade , Fatores Sexuais
11.
Radiologe ; 52(3): 207-12, 2012 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-22274657

RESUMO

CLINICAL ISSUE: The introduction of image-guided radiotherapy (IGRT) has changed the workflow in radiation oncology more dramatically than any other innovation in the last decades. STANDARD TREATMENT: Imaging for treatment planning before the initiation of the radiotherapy series does not take alterations in patient anatomy and organ movement into account. TREATMENT INNOVATIONS: The principle of IGRT is the temporal and spatial connection of imaging in the treatment position immediately before radiation treatment. DIAGNOSTIC ASSESSMENT: The actual position and the target position are compared using cone-beam computed tomography (CT) or stereotactic ultrasound. PERFORMANCE: The IGRT procedure allows a reduction of the safety margins and dose to normal tissue without an increase in risk of local recurrence. ACHIEVEMENTS: In the future the linear treatment chain in radiation oncology will be developed based on the closed-loop feedback principle. PRACTICAL RECOMMENDATIONS: The IGRT procedure is increasingly being used especially for high precision radiotherapy, e.g. for prostate or brain tumors.


Assuntos
Imageamento Tridimensional/tendências , Padrões de Prática Médica/tendências , Radiocirurgia/tendências , Radioterapia Guiada por Imagem/tendências , Humanos
12.
Rofo ; 183(12): 1130-7, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-22068844

RESUMO

PURPOSE: The German Society of Senology (step-3 guidelines for the early recognition of breast cancer in Germany) recommends whole-body staging including chest X-ray, ultrasound of the liver and bone scintigraphy before systemic therapy in patients with breast cancer. The performance of these three examinations is time-consuming and involves radiation exposure. Whole-body MR imaging (WB-MRI) allows staging in a single examination without radiation exposure. The purpose of this study was to compare the diagnostic accuracy of WB-MRI with staging according to the guidelines. MATERIALS AND METHODS: During 04/07 and 06/09, the initial staging in 51 patients (56 ± 12 yrs) with breast cancer (24 patients with lymph node metastases) was performed according to the S 3-guidelines. Additionally, all patients underwent contrast-enhanced WB-MRI (1.5-Tesla-Magnetom Avanto, Siemens, Erlangen). The findings of the different modalities were compared after correlation of the lesions by follow-up. The detection of suspicious findings and the accuracy of prediction of malignancy of the detected lesions were evaluated. RESULTS: Overall, 14 metastases were detected in 4 of 51 patients after completion of the follow-up. By means of WB-MRI, all 14 metastases could be detected, while just 4 of these metastases were identified by the conventional methods. CONCLUSION: The detection of distant metastases has an important impact on patient management. In this study WB-MRI in breast cancer staging has shown promising results in regard to possible clinical implementation as a matter of routine staging.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Adenocarcinoma/diagnóstico , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Carcinoma Lobular/diagnóstico , Progressão da Doença , Feminino , Alemanha , Fidelidade a Diretrizes , Humanos , Metástase Linfática/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Sensibilidade e Especificidade
13.
Sportverletz Sportschaden ; 22(3): 146-52, 2008 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-18814056

RESUMO

INTRODUCTION: The goal of this work was to assess the accuracy of the MR-Arthrografie in the evaluation of over head athletes injuries in comparison with athroscopy. MATERIAL AND METHODS: In 29 patients (middle age: 30 years, 21 male, 8 female, age 16 - 53 years) with persistent pain after conservative therapy an Arthro-MRI with intraarticular application of gadolinum was performed prior to arthroscopic surgery. The MRI was retrospectivly analysed of three examiners independently from one another. The result were compared to the results of the Arthroscopy. Interrater Reliability was calculated by using of Cohens Kappa. RESULTS: The MR-Arthrography could demonstrate 8 of 9 (88.9 %) partial tears of he rotator cuff. All SLAP (Superiores Labrum from Anterior to Posterior) Lesions as well as all bankart type Lesions were recognized through the MR-Arthrography. However, dependent upon the experience of the examiner in a span between 33.3 % (fellow radiologist) and 93.3 % (consultant radiologist). We found a high agreement between consultant radiologist and shoulder surgeon with Kappa of 0.79 for rotator cuff tear-, 0.86 for Bankart- and 0.82 for SLAP-Läsionen.


Assuntos
Artrografia/métodos , Artroscopia/métodos , Traumatismos em Atletas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Luxação do Ombro/diagnóstico , Lesões do Ombro , Articulação do Ombro/patologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Z Gastroenterol ; 46(1): 58-68, 2008 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-18188818

RESUMO

The diagnosis of and therapy for cholangiocarcinomas still remains an interdisciplinary challenge. For diagnostic and therapeutic purposes intra- and extrahepatic cholangiocarcinomas need to be distinguished. Multiple imaging tools such as sonography, multidetector computer tomography, magnetic resonance tomography as well as endoscopic ultrasound and endoscopic retrograde cholangiography for the diagnosis and localisation of these tumours are available. To date, surgical resection is the only curative treatment. At the time of diagnosis, most of the tumours are advanced. Therefore, only a small percentage of patients are suitable for curative surgery. Infiltration of the portal vein no longer constitutes a contraindication for surgery. Liver transplantation is not a reasonable option for intrahepatic cholangiocarcinomas but may be of advantage for perihilar Klatskin tumours. Severe cholangitis is the main cause of death of patients with obstructive cholangiocarcinomas. Drainage of the biliary tree system or surgery with construction of a biliary-digestive anastomosis is often necessary. If possible, a photodynamic therapy (PDT) should be performed in addition to biliary drainage. PDT has been shown to facilitate biliary drainage and to improve survival. The value of radiologist-assisted interventional procedures as well as percutaneous ablation and radiochemotherapy is not well established. In addition, so far, there is no standardised chemotherapy in a palliative situation established but there is some evidence for a benefit of gemcitabine-based chemotherapy. For the best care and treatment of patients with cholangiocarcinomas an interdisciplinary approach is required and to achieve progress in the therapy patients should be included in prospective clinical trials to test new approaches.


Assuntos
Neoplasias dos Ductos Biliares , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma , Ducto Hepático Comum , Tumor de Klatskin , Algoritmos , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/mortalidade , Colangiocarcinoma/cirurgia , Colangiopancreatografia Retrógrada Endoscópica , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Drenagem , Endossonografia , Humanos , Tumor de Klatskin/diagnóstico , Tumor de Klatskin/cirurgia , Transplante de Fígado , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Gencitabina
15.
Rofo ; 178(10): 1014-21, 2006 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-17021980

RESUMO

PURPOSE: In congenital heart disease, the exact determination of the right ventricular function is of high importance for therapeutic and especially surgical planning. The aim of this study was to correlate the parameters of the right ventricular function in MRI and 3D echocardiography to determine the agreement of both modalities. MATERIALS AND METHODS: In 18 patients suffering from congenital heart disease, 3D echocardiography was performed using a Philips Sonos 7500 system. In MRI short axis slices with a 4-mm distance were acquired using an SSFP sequence on a Siemens Sonata or Symphony System. Volumetry for both modalities was performed on an external workstation (Tomtec) using the EchoView software. RESULTS: Enddiastolic and endsystolic volumes showed a highly significant correlation with coefficients of 0.996 and 0.990, respectively. In echocardiography there was a systematic slight underestimation of enddiastolic volumes and overestimation of endsystolic volumes. The Wilcoxon test did not show significant differences between the volumes and ejection fractions assessed by both modalities. CONCLUSION: There is an excellent correlation in the quantification of right ventricular volumes in MRI and 3D echocardiography, which allows a comparison of acquired volumes in clinical follow-up.


Assuntos
Ecocardiografia Tridimensional/métodos , Cardiopatias Congênitas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Disfunção Ventricular Direita/diagnóstico , Adolescente , Criança , Feminino , Cardiopatias Congênitas/complicações , Humanos , Lactente , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto , Disfunção Ventricular Direita/etiologia
16.
Neurobiol Aging ; 27(8): 1051-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16169126

RESUMO

Clinical utility of magnetic resonance imaging (MRI) for the diagnosis and assessment of neurodegenerative diseases may depend upon the reliability of MRI measurements, especially when applied within a multicenter context. In the present study, we assessed the reliability of MRI through a phantom test at a total of eleven clinics. Performance and entry criteria were defined liberally in order to support generalizability of the results. For manual hippocampal volumetry, automatic segmentation of brain compartments and voxel-based morphometry, multicenter variability was assessed on the basis of MRIs of a single subject scanned at ten of the eleven sites. In addition, cranial MRI scans obtained from 73 patients with Alzheimer's disease (AD) and 76 patients with mild cognitive impairment were collected at subset of six centers to assess differences in grey matter volume. Results show that nine out of eleven centers tested met the reliability criteria of the phantom test, where two centers showed aberrations in spatial resolution, slice thickness and slice position. The coefficient of variation was 3.55% for hippocampus volumetry, 5.02% for grey matter, 4.87% for white matter and 4.66% for cerebrospinal fluid (CSF). The coefficient of variation was 12.81% (S.D.=9.06) for the voxel intensities within grey matter and 8.19% (S.D.=6.9) within white matter. Power analysis for the detection of a difference in the volumes of grey matter between AD and MCI patients across centers (d=0.42) showed that the total sample size needed is N=180. In conclusion, despite minimal inclusion criteria, the reliability of MRI across centers was relatively good.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Transtornos Cognitivos/diagnóstico , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Alemanha , Humanos , Masculino , Países Baixos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Radiologe ; 44(2): 146-51, 2004 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-14991133

RESUMO

PURPOSE: The aim of the study was to compare the diagnostic accuracy in imaging viability of the myocardium with a multislice inversions recovery 2D single shot TrueFISP sequence and an established inversion recovery TurboFlash sequence. MATERIAL AND METHODS: Twelve patients with myocardial infarction were examined at a 1.5 tesla MR system (Sonata, Siemens, Medical Systems) 10 min after application of a single dose multihance (0,1 mmol/kg body weight) with a 2D multislice technique (inversion recovery single shot TrueFISP), that allows to image the entire short axis during one breathhold and a 2D single slice technique (inversion recovery TurboFlash), that requires one breathhold per slice. Signal intensity was determined in normal myocardium, in the infarcted myocardium and in the left ventricle. The contrast/noise ratio of normal and infarcted myocardium was determined. The areas of hyperintense infarction were compared for both sequence techniques. RESULTS: The multislice single shot 2D IR-TrueFisp sequence has a lower contrast/noise ratio than the IR-TurboFlash sequence (mean values 6.9 vs. 12.5) for viable and non viable myocardium. The assessment of the volume of the infarction is possible with excellent correlation of both techniques (r=0.97, p <0.036). In addition, an assessment of the transmural extent of the infarction is possible with identical spatial resolution. CONCLUSION: The inversions recovery 2D single shot TrueFisp technique allows for accurate detection of the infarction, for accurate determination of the area of the infarction and for assessment of the transmural extent of the infarction with high spatial resolution.


Assuntos
Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Meglumina/análogos & derivados , Contração Miocárdica/fisiologia , Infarto do Miocárdio/diagnóstico , Miocárdio/patologia , Sobrevivência de Tecidos/fisiologia , Adulto , Idoso , Artefatos , Meios de Contraste/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Compostos Organometálicos , Músculos Papilares/patologia , Sensibilidade e Especificidade , Disfunção Ventricular/diagnóstico , Disfunção Ventricular/fisiopatologia
18.
Radiologe ; 42(11): 909-15, 2002 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-12458444

RESUMO

To evaluate the weakly protein interacting MR contrast agent MultiHance((R)) and the one-molar agent Gadovist((R)) for cerebral perfusion MR imaging, a randomized intraindividual study was conducted in 12 healthy male volunteers. Perfusion-MRI was performed with single and double dose of each contrast agent on a 1.5T MR system using a gradient-echo EPI sequence. The imaging parameters, slice positioning and contrast media application were standardized. For the quantitative assessment rCBV and rCBF measurements of gray and white matter were performed. Additionally, the percentage of signal drop and the full width half maximum (FWHM) of ROI signal time curves were quantified. In a qualitative analysis the image quality of the rCBV and rCBF maps were assessed. Single dosage of the used new contrast agents was sufficient to achieve high quality perfusion maps. The susceptibility effect, described by percentage of signal loss (Gadovist((R)): 29.4% vs. MultiHance((R)): 28.3%) and the FWHM (Gadovist((R)): 6.4 s vs. Multihance((R)): 7.0 s) were not different between the agents for single dose. The one molar MR contrast agent Gadovist((R)) has no advantages over MultiHance((R)), a MR contrast agent with a higher relaxivity in perfusion MRI. Both agents allow the calculation of high quality perfusion maps at a dosage of 0.1 mmol/kg bw with physiologic absolute values for regional CBV and CBF. The susceptibility effect is comparable for both agents and stronger than with conventional MR contrast media.


Assuntos
Encéfalo/irrigação sanguínea , Meios de Contraste , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Humanos , Masculino , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Sensibilidade e Especificidade , Método Simples-Cego
19.
Radiologe ; 39(2): 151-60, 1999 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-10093841

RESUMO

This study demonstrates the value of a fast fluid-attenuated inversion-recovery (FLAIR) technique in the assessment of cerebral gliomas and metastases. Thirty-five patients with cerebral gliomas and 12 patients with a total of 39 cerebral metastases were examined by T2/proton density-weighted fast spin echo, fast FLAIR with and without contrast medium and contrast-enhanced T1-weighted spin echo using identical slice parameters. The images were evaluated using quantitative and qualitative criteria. Quantitative criteria were tumor-to-background and tumor-to-cerebrospinal fluid contrast and contrast-to-noise. The qualitative evaluation was performed as a multireader analysis concerning lesion detection, lesion delineation and image artifacts. In the qualitative evaluation, all readers found fast FLAIR to be superior to fast spin echo in the exact delineation of cerebral tumors (P < 0.001) and the delineation of enhancing and non-enhancing tumor parts. Fast FLAIR was superior in the delineation of cortically located and small lesions but was limited in lesions adjacent to the ventricles. Fast FLAIR provided significantly better tumor-to-CSF contrast and tumor-to-CSF contrast-to-noise (P < 0.001). The tumor-to-background contrast and tumor-to-background contrast-to-noise of the fast FLAIR images were lower than that of T2-weighted spin-echo images but were significantly increased after the application of contrast medium. FLAIR images had a more image artifacts, but these influenced the image interpretation in only two patients. Signal hyperintensities at the ventricular border were present in 92% of the patients. These are common findings in fast FLAIR and should be included in image interpretation.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Magnetoencefalografia , Neoplasias Encefálicas/cirurgia , Meios de Contraste , Feminino , Glioma/secundário , Glioma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino
20.
Rofo ; 169(5): 499-504, 1998 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-9849600

RESUMO

PURPOSE: Purpose of this study is to compare functional MRI parameters with histomorphological markers of tumor microvessel density (MVD) and permeability (vascular endothelial growth factor) and to determine the ultimate value of both approaches by correlation with disease outcome in patients with primary cancer of the uterine cervix. METHOD: Pharmacokinetic parameters were calculated from contrast-enhanced dynamic MR imaging series in 37 patients with biopsy-proven primary cervical cancer. On the operative whole mount specimens, histomorphological markers of tumor angiogenesis (MVD, VEGF) were compared with the MRI-derived parameters. For MRI and histomorphological data, Kaplan-Meier survival curves were calculated and compared using logrank statistics. RESULTS: Significant (p < 0.05-0.01) associations were found between MVD and dynamic MRI parameters. No significant relationships were observed between VEGF expression and dynamic MRI parameters. Disease outcome was better assessed with dynamic MRI parameters than with the histomorphological approach. CONCLUSIONS: It is concluded that 1) the pathophysiological basis for the amplitude A in dynamic MRI is MVD but not VEGF expression; and 2) a functional, dynamic MRI approach may be more suited to assess angiogenic activity in terms of patient survival than current histomorphological-based markers of tumor angiogenesis.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/diagnóstico , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/patologia , Adulto , Análise de Variância , Biomarcadores , Biópsia , Capilares/patologia , Fatores de Crescimento Endotelial/análise , Fator VIII/análise , Feminino , Seguimentos , Humanos , Linfocinas/análise , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Prognóstico , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/cirurgia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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