RESUMO
The primary purpose of this work was to assess long-term in vitro reproducibility of metabolite levels measured using 1H MRS (proton magnetic resonance spectroscopy). The secondary purpose was to use the in vitro results for interpretation of 1H MRS in vivo spectra acquired from patients diagnosed with Canavan disease. 1H MRS measurements were performed in the period from April 2006 to September 2010. 118 short and 116 long echo spectra were acquired from a stable phantom during this period. Change-point analysis of the in vitro N-acetylaspartate levels was exploited in the computation of fT factor (ratio of the actual to the reference N-acetylaspartate level normalized by the reciprocity principle). This coefficient was utilized in the interpretation of in vivo spectra analyzed using absolute reference technique. The monitored time period was divided into six time intervals based on short echo in vitro data (seven time intervals based on long echo in vitro data) characterized by fT coefficient ranging from 0.97 to 1.09 (based on short echo data) and from 1.0 to 1.11 (based on long echo data). Application of this coefficient to interpretation of in vivo spectra confirmed increased N-acetylaspartate level in Canavan disease. Long-term monitoring of an MRS system reproducibility, allowing for absolute referencing of metabolite levels, facilitates interpretation of metabolic changes in white matter disorders.
Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Doença de Canavan/diagnóstico , Doença de Canavan/metabolismo , Diagnóstico por Computador/métodos , Espectroscopia de Prótons por Ressonância Magnética/instrumentação , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adolescente , Adulto , Algoritmos , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Técnicas In Vitro , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pesquisa Translacional Biomédica , Adulto JovemRESUMO
OBJECTIVE: This prospective multicenter intraindividual crossover study was designed to compare gadobenate dimeglumine and gadofosveset trisodium at approved doses with respect to the image quality and diagnostic performance of contrast-enhanced MR angiography (CE-MRA) in the detection of clinically relevant renal artery stenosis. SUBJECTS AND METHODS: Thirty-nine subjects (17 men, 22 women; age range, 30-86 years; mean 62 +/- 13.3 [SD] years) with known or suspected renovascular disease underwent a first CE-MRA examination with 0.1 mmol/kg gadobenate dimeglumine and a second examination 3-12 days later with 0.03 mmol/kg gadofosveset. Identical T1-weighted spoiled gradient-refocused echo coronal first-pass images were acquired for 38 of the 39 patients. For 15 of the 38 patients, additional sagittal or axial images or both were acquired with gadofosveset during the steady-state phase. Thirty-four patients underwent digital subtraction angiography, which was the reference standard. Three independent blinded readers assessed source images and maximum-intensity-projection reconstructions to detect clinically relevant (> 50%) renal artery stenosis. Diagnostic performance (sensitivity, specificity, accuracy, positive and negative predictive values) was evaluated with the McNemar and Wald tests. Matched-pair determinations of diagnostic preference were evaluated with Wilcoxon's signed rank test. Reader agreement was determined with kappa analysis, and safety was assessed. RESULTS: Comparison of first-pass images revealed superior sensitivity (75.7-86.5% vs 68.4-76.3%), specificity (92.1-98.6% vs 90.5-93.9%), accuracy (88.9-96.2% vs 85.9-90.3%), positive predictive value (70.0-94.1% vs 65.0-76.3%), and negative predictive value (94.0-96.6% vs 91.7-93.9%) with gadobenate dimeglumine. Significant superiority was noted for specificity (p < or = 0.02), accuracy (p < or = 0.005), and positive predictive value (p < or = 0.018). Steady-state images showed no benefit of gadofosveset. Reader agreement was good to excellent (gadobenate dimeglumine, kappa = 0.855; gadofosveset, kappa = 0.776). Reader preference was for gadobenate dimeglumine in 11, 17, and 13 patients and for gadofosveset in five, four, and five patients. No safety concerns were noted. CONCLUSION: Better diagnostic performance and reader preference were found for gadobenate dimeglumine than gadofosveset in first-pass renal CE-MRA.
Assuntos
Gadolínio , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos , Obstrução da Artéria Renal/diagnóstico , Artéria Renal/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Estudos Cross-Over , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To prospectively determine diagnostic performance and safety of contrast material-enhanced (CE) magnetic resonance (MR) angiography with 0.1 mmol per kilogram of body weight gadobenate dimeglumine for depiction of significant steno-occlusive disease (> or =51% stenosis) of renal arteries, with digital subtraction angiography (DSA) as reference standard. MATERIALS AND METHODS: This multicenter study was approved by local institutional review boards; all patients provided written informed consent. Patient enrollment and examination at centers in the United States complied with HIPAA. Two hundred ninety-three patients (154 men, 139 women; mean age, 61.0 years) with severe hypertension (82.2%), progressive renal failure (11.3%), and suspected renal artery stenosis (6.5%) underwent CE MR angiography with three-dimensional spoiled gradient-echo sequences after administration of 0.1 mmol/kg gadobenate dimeglumine at 2 mL/sec. Anteroposterior and oblique DSA was performed in 268 (91.5%) patients. Three independent blinded reviewers evaluated CE MR angiographic images. Sensitivity, specificity, and accuracy of CE MR angiography for detection of significant steno-occlusive disease (> or =51% vessel lumen narrowing) were determined at segment (main renal artery) and patient levels. Positive and negative predictive values and positive and negative likelihood ratios were determined. Interobserver agreement was analyzed with generalized kappa statistics. A safety evaluation (clinical examination, electrocardiogram, blood and urine analysis, monitoring for adverse events) was performed. RESULTS: Of 268 patients, 178 who were evaluated with MR angiography and DSA had significant steno-occlusive disease of renal arteries at DSA. Sensitivity, specificity, and accuracy of CE MR angiography for detection of 51% or greater stenosis or occlusion were 60.1%-84.1%, 89.4%-94.7%, and 80.4%-86.9%, respectively, at segment level. Similar values were obtained for predictive values and for patient-level analyses. Few CE MR angiographic examinations (1.9%-2.8%) were technically inadequate. Interobserver agreement for detection of significant steno-occlusive disease was good (79.9% agreement; kappa = 0.69). No safety concerns were noted. CONCLUSION: CE MR angiography performed with 0.1 mmol/kg gadobenate dimeglumine, compared with DSA, is safe and provides good sensitivity, specificity, and accuracy for detection of significant renal artery steno-occlusive disease.
Assuntos
Angiografia Digital , Meios de Contraste , Angiografia por Ressonância Magnética , Meglumina/análogos & derivados , Compostos Organometálicos , Obstrução da Artéria Renal/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Artéria Renal/diagnóstico por imagem , Artéria Renal/patologia , Obstrução da Artéria Renal/diagnóstico por imagem , Sensibilidade e EspecificidadeRESUMO
CT perfusion is a new diagnostic method which enables imaging of the hemodynamics of tissues and organs. Until now most of the publications have been focused on the use of this technique to assess acute stroke. The aim of the presented work is to show the role of CT perfusion in the diagnosis of cerebral gliomas. These tumors are characterized by intensive vascularity which results in an increased blood volume (CBV), blood flow (CBF) and permeability surface (PS) values in perfusion CT examination. A correlation has been reported between perfusion parameters and the histopathological tumor grade. CT perfusion provides morphological and functional information which is useful in the diagnosis, planning treatment strategies and monitoring of the therapeutic effect in cerebral gliomas.
Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/fisiopatologia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Glioma/diagnóstico , Glioma/fisiopatologia , Tomografia Computadorizada por Raios X , Volume Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Hemodinâmica/fisiologia , HumanosAssuntos
Cardiomiopatia Dilatada/diagnóstico , Imageamento por Ressonância Magnética , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/terapia , Cardiomiopatia Hipertrófica/diagnóstico , Diagnóstico Diferencial , Cardiopatias Congênitas/diagnóstico , Hemossiderose/complicações , Hemossiderose/diagnóstico , Humanos , Miocardite/diagnósticoRESUMO
BACKGROUND: In virtual colonoscopy (VC) we are capable to assess all organs located between a diaphragm and pelvic bottom. This report provides a breakdown of extracolonic pathological findings in VC performed in standard indications. MATERIAL/METHODS: We reviewed 71 consecutive VC (29 men and 42 women) performed using double-slice scanner General Electric High Speed NX/I Pro. Pathological findings were presented in a tabular form illustrated by sample images. RESULTS: Extracolonic findings were found in 53 cases (74.6%), and were equally frequent in subgroups with pathological colon and free from colon lesions. Renal cysts occurred most often. In 15 cases the extracolonic pathologies were clinically important, most of them tumors. CONCLUSIONS: VC is found to be a very useful tool in the detection and evaluation of extracolonic pathologies.
Assuntos
Colonografia Tomográfica Computadorizada/métodos , Achados Incidentais , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças do Colo/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Feminino , Humanos , Doenças Renais Císticas/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Adulto JovemRESUMO
BACKGROUND: Magnetic resonance (MR) has become the most important imaging method in the diagnosis of intracranial tumours. However, conventional MR protocol often fails to obtain all morphological details which are necessary for precise planning of the treatment. Therefore, there are attempts of introducing other MR techniques, to gain new information concerning tumour morphology. One such technique is FLAIR sequence. In previous papers we presented the value of plain FLAIR in patients with intracranial tumours. The aim of the present study was evaluation of contrast enhanced FLAIR (CE FLAIR) in assessment of intracranial tumours. MATERIAL/METHODS: MR examinations, including conventional T1 (pre-and postcontrast) and T2 images, as well as plain and contrast-enhanced FLAIR sequences were performed in 27 patients with intracranial tumours. In all patients the degree and localization of contrast enhancement in post-contrast T1-weighted sequence (CE T1w) and CE FLAIR images have been compared. RESULTS: Contrast enhancement of the tumour in both CE T1-w and CE FLAIR sequences was found in 18 patients. In 5 patients the enhancement was visible only on T1-weighted images, while in 2 cases only on FLAIR images. Among 18 patients, who demonstrated enhancement both in T1-weighted and FLAIR sequences, in 9 cases the effect of enhancement was better on T1-weighted images, in 7-CE FLAIR gave superior results, and in 2 patients - both methods were equivalent. In the whole material in 9 cases CE-FLAIR was superior in 14-inferior and in 4-equal to CE-T1-w. Among 9 cases in which CE- FLAIR was superior, in 7 patients the enhancement concerned the border of the tumour or postoperative cave. CONCLUSIONS: Contrast-enhanced FLAIR has limited value in assessment of intracranial tumours and should be used as a supplementary technique if there are difficulties in evaluation of tumour morphology in other sequences.
Assuntos
Neoplasias Encefálicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Astrocitoma/diagnóstico , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Criança , Meios de Contraste , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Meningioma/patologia , Pessoa de Meia-Idade , Adulto JovemRESUMO
For over 2 years, we have had access to latest generation apparatus and software for planning and stereotactic treatment as well as for x-rays treatment. Until now, we have carried out over 100 procedures. These included 52 stereotactic biopsies of neoplasms, some of them located within the structures of the posterior fossa. In this report, we have discussed the possibilities and effectiveness of diagnosis and treatment of tumours located in different structures, including posterior cave. In the study, we used stereotactic methods. We have described biopsies of the following tumours: cerebellar hemisphere tumour (diagnosed as "metastatic atypic planoepitheliale carcinoma" in a patient with coexisting orbit lymphoma), a bifocal lesion (located in cerebellar hemisphere and cerebellar peduncle, diagnosed as pilocytic astrocytoma of WHO malignancy grade II/III), and lesion (located in the pons, diagnosed as pilocytic astrocytoma WHO grade II).
Assuntos
Neoplasias Infratentoriais/diagnóstico , Neoplasias Infratentoriais/cirurgia , Técnicas Estereotáxicas , Adulto , Idoso , Biópsia , Braquiterapia , Humanos , Imuno-Histoquímica , Neoplasias Infratentoriais/radioterapia , Pessoa de Meia-Idade , RadiocirurgiaRESUMO
Myositis Ossificans Progressiva (MOP) is a rare hereditary condition with ectopic ossifying. This case report demonstrates clinical picture of MOP and possibilities of diagnosis.
Assuntos
Miosite Ossificante/diagnóstico , Adolescente , Feminino , Humanos , Radiografia Torácica , Tomografia Computadorizada por Raios XRESUMO
Myositis ossificans progressiva (MOP) is a rare hereditary connective tissue disorder. Skeletal abnormalities and progressive ectopic ossifications are features of this condition. Diagnosis is often delayed because of heterogenous picture of MOP. Treatment is unknown, so MOP leads to prolonged disability.
Assuntos
Miosite Ossificante , Diagnóstico Diferencial , Humanos , Miosite Ossificante/diagnóstico , Miosite Ossificante/terapiaRESUMO
The aim of project is to build a European network, which will integrate the research capabilities of a group of research institutes and university departments to provide an infrastructure for the highest quality research in psychiatric disorders, particularly in schizophrenia and schizoaffective disturbances. This network will integrate original computer expert advisory system called "Saba" with modern brain imaging techniques and neurophysiological methods, which allows for the delineation of specific subtypes and particular episodes of mental disorders and their neural bases will be studied by state-of-the art (high tech) imaging techniques. This approach will lead to new investigatory, diagnostic and therapeutic techniques. Together the members of this network will comprise an unmatched critical mass of human and other resources aimed at fundamental and applied research into a group of disorders, which impose a huge burden on social and material capital. The relationships and mutual responsibilities between neuroscience and the society it serves will be addressed specifically. Top brain research is performed at several locations in Europe. In particular, in the area of linking classical psychiatric and psychological assessment methods and the newest brain imaging techniques in mental disorders, major progress can only be made when various research groups join their efforts. Large-scale studies using different databases are critically required, which demands standardization of the description of mental disorders and of the applied techniques and methods of analysis. Imaging techniques, including functional MRI (fMRI), Evoked Potentials (EPs), brain mapping, and the computer gathered information will be shared, standardized and further developed within the network. Developing new information technology tools for simulation, visualization and data-mining will be required to enable effective search for links between mental disorders and brain characteristics (function, structure) in very large scale data-sets acquired and stored in various research facilities.
Assuntos
Encéfalo/fisiopatologia , Conhecimentos, Atitudes e Prática em Saúde , Esquizofrenia/diagnóstico , Esquizofrenia/prevenção & controle , Europa (Continente) , Potenciais Evocados Auditivos , Potenciais Evocados Visuais , Humanos , Processamento de Imagem Assistida por Computador , Cooperação Internacional , Imageamento por Ressonância Magnética , Serviços de Saúde Mental/organização & administração , Testes Neuropsicológicos/normas , Neurociências/métodos , Polônia , Avaliação de Programas e Projetos de Saúde , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Sociedades Médicas/normasRESUMO
WHO has classified depression disturbances--due to widespread existence and serious medical consequences and resulting social and economic effects--as a priority health problem in all the developed countries. The significance of the depression disturbances is fully comparable to such illnesses as heart diseases, cancer and HIV infection. The research made in the USA (NIMH programmer) shows that first contact doctors are not able to detect depression in relation to 50-70% of the people ill with it. Also the research made in other countries shows that a doctor properly identifies only one out of four persons with clear indications of depression. The wrong choice of the antidepressant drug may result in inefficient therapy and in growing risk of suicide. In 1993 the analysis of 50 best selling medicines in the EU made by two Italian pharmacologists showed that in France and Italy in over 45% of the cases the medicines with doubtful efficiency are applied. The aim of our project is to build a European network, which will integrate the research capabilities of a group of research institutes and university departments to provide an infrastructure for creation of the computer advisory system for diagnostics of affective disorders. This network will integrate our original computer expert advisory system called "Salomon" with modem brain imaging techniques and neurophysiological methods, which allows for the delineation of specific subtypes and particular episodes of mental disorders and their neural bases will be studied by state-of-the art (high tech) imaging techniques. This approach will lead to new investigatory, diagnostic and therapeutic techniques.
Assuntos
Transtorno Depressivo/diagnóstico , Transtorno Depressivo/terapia , Sistemas Inteligentes , Prevenção Primária/normas , Antidepressivos/normas , Mapeamento Encefálico , Transtorno Depressivo/prevenção & controle , Diagnóstico por Computador , Diagnóstico Diferencial , Europa (Continente) , Medicina Baseada em Evidências , Humanos , Cooperação Internacional , Imageamento por Ressonância Magnética , Programas de Rastreamento/métodos , Testes Neuropsicológicos , Polônia , Atenção Primária à Saúde/normas , Avaliação de Programas e Projetos de Saúde , Psicometria , Garantia da Qualidade dos Cuidados de Saúde , Estados UnidosRESUMO
The paper presents new ways of visualizing internal structures of the large intestine. Use of spiral computed tomography (CT) or magnetic resonance imaging (MRI) combined with appropriate software leads to imaging that can be compared with colonoscopy or double contrast enema. The authors discuss patients' preparation, methods for CT and MRI variants, indications, advantages and costs.
Assuntos
Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Colonografia Tomográfica Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Tomografia Computadorizada Espiral/métodos , Neoplasias do Colo/prevenção & controle , Pólipos do Colo/prevenção & controle , Colonografia Tomográfica Computadorizada/economia , Colonoscopia/métodos , Humanos , Processamento de Imagem Assistida por Computador/economia , Imageamento Tridimensional/economia , Polônia , Valores de Referência , Sensibilidade e Especificidade , Tomografia Computadorizada Espiral/economiaRESUMO
Background. MRIs were obtained from 24 patients with suspicion of small pelvis pathology, with no indication of hip joint pathology.
Results and Conclusions. Based on the normal descriptive and topographical anatomy of the hip joint and its vicinity, the authors identified on the MRIs the main bony, muscular, vascular and nervous structures comprising and surrounding the hip joint. A clinical division of the muscles surrounding the hip joints is proposed.