Navegando por Palavras-chave "imagem por ressonância magnética"
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- ItemSomente MetadadadosAspectos de imagem dos sarcomas primários da mama: revisão da literatura e série de casos(Universidade Federal de São Paulo (UNIFESP), 2016-12-21) Alves, Aldo Maurici Araujo [UNIFESP]; Mello, Giselle Guedes Netto de Mello [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: To review the imaging aspects of primary breast sarcomas (PMS). Methods: a qualitative observational study through a series of case reports and literature revision. Cases of PMS were collected with histopathological confirmation And accessible imaging (mammography, ultrasound or magnetic resonance imaging), From two university hospitals and a private service. The literature review was Performed through the search of indexed works in the MEDLINE database. Results: 10 cases were found within the selection criteria, and their respective Findings were presented and discussed together with the literature. Conclusion: there is significant overlap between the mammographic findings, And magnetic resonance imaging of mammary carcinomas and sarcomas. However, a rapidly growing circumscribed mass without calcifications in the Mammography, without axillary lymph node involvement, complex-appearing solid-cystic On ultrasound and magnetic resonance imaging may suggest a PMS.
- ItemAcesso aberto (Open Access)Contribuição do índice de intensidade de sinal na sequência t1 desvio químico associado à espectroscopia por ressonância magnética no diagnóstico dos adenomas adrenais(Universidade Federal de São Paulo (UNIFESP), 2016-12-15) Dalavia, Claudio Carvalho [UNIFESP]; Ajzen, Sergio Aron [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE. To investigate the advantages of using modified signal intensity measurements on chemical shift imaging alone or correlate with proton spectroscopy in the differential diagnosis of adrenal adenomas. SUBJECTS AND METHODS. 97 patients (69 adenomas, 8 carcinomas, 14 pheochromocytomas, 4 metastasis, 1 myelolipoma and 1 granulomatous lesion) underwent chemical shift imaging and spectroscopy. Signal intensity index was calculated as [(signal intensity on in-phase image ? signal intensity on out-of-phase image) / (signal intensity on in-phase image)] × 100%. The averages of three minimum, mean, and maximum signal intensity values measured on three consecutive images, in the smaller lesions if not possible we use one or two images, with the region of interest covering one-half to two-thirds of the mass. All indexes were compared with spectroscopy metabolite ratios (lactate/creatine, glutamine-glutamate/creatine, choline/creatine, choline/lipid, 4.0?4.3 ppm/creatine, and lipid/creatine) for each type of adrenal mass. RESULTS. All signal intensity measurements and spectroscopy metabolite ratios were significant to the differentiation between adenomas and no adenomas, except Lip/Cr and Cho/Lip. Was not possible to apply the spectroscopy in 37,75% of the cases. CONCLUSION. The signal intensity index and spectroscopy metabolite ratios increased the accuracy of the differential diagnosis of adrenal adenomas.
- ItemAcesso aberto (Open Access)Espectroscopia por ressonância magnética de prótons em epilepsia mioclônica juvenil sugere o comprometimento de uma rede neuronal específica(Liga Brasileira de Epilepsia (LBE), 2008-09-01) Lin, Katia [UNIFESP]; Carrete Junior, Henrique [UNIFESP]; Lin, Jaime [UNIFESP]; Peruchi, M.m. [UNIFESP]; Araujo Filho, Gerardo Maria de [UNIFESP]; Pascalicchio, T.f. [UNIFESP]; Guaranha, Mirian Salvadori Bittar [UNIFESP]; Guilhoto, Laura Maria de Figueiredo Ferreira [UNIFESP]; Yacubian, Elza Márcia Targas [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVES: The neuroanatomical basis and the neurochemical abnormalities that underlay juvenile myoclonic epilepsy (JME) are not fully defined. While the thalamus plays a central role in synchronization of widespread regions of the cerebral cortex during a seizure, emerging evidence suggests that all cortical neurons may not be homogeneously involved. The purpose of this study was to investigate the cerebral metabolic differences between patients with JME and normal controls. METHODS: All patients had a JME diagnosis based on seizure history and semiology, EEG recording, normal magnetic resonance neuroimaging (MRI) and video-EEG. Forty JME patients (JME-P) were submitted to 1.5 T MRI proton spectroscopy (1H-MRS), multi-voxel with PRESS sequence (TR/TE = 1500/30 ms) over the following locations: prefrontal cortex (PC), frontal cortex (FC), thalamus, basal nuclei, posterior cingulate gyrus (PCG), insular, parietal and occipital cortices. We determined ratios for integral values of N-acetyl aspartate (NAA) and glutamine-glutamate (GLX) over creatine-phosphocreatine (Cr). The control group (CTL) consisted of 20 age and sex-matched healthy volunteers. RESULTS: Group analysis demonstrated a tendency for lower NAA/Cr ratio of JME-P compared to CTL predominantly on FC, PC, thalamus and occipital cortex. When compared to CTL, JME-P had a statistically significant difference in GLX/Cr on FC, PC, insula, basal nuclei, PCG and on thalamus. When evaluating the relationship among the various components of this epileptic network among JME-P, the strongest correlation occurred between thalamus and PC. Also, we found a significant negative correlation between NAA/Cr and duration of epilepsy. CONCLUSION: Reductions in NAA may represent loss or injury of neurons and/or axons, as well as metabolic dysfunction while glutamate is considered to be an excitatory neurotransmitter in the brain which is involved in the pathogenesis of epileptogenic seizures.
- ItemAcesso aberto (Open Access)Estudo de artrodese lombar minimamente invasiva lateral transpsoas: análise de parâmetros radiológicos, afundamento do espaçador intersomático e suas correspondências clínicas(Universidade Federal de São Paulo (UNIFESP), 2016-06-28) Marchi, Luis Henrique Larcher [UNIFESP]; Abdala, Nitamar [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)To investigate the event of sinking of the intersomatic spacer in lumbar fusion procedures by the XLIF method without the use of transpedicular screw supplementation. Methods: In the investigation of time of onset, clinical significance and protective factors, we used a retrospective analysis of a first cohort: 74 cases treated with XLIF. The cases were divided into two groups according to the spacer that was used 18mm and 22mm. Radiological and clinical parameters were evaluated up to one year postoperatively. In lateral radiographs we used a gradation of sinking of the spacer (degree 0-III). In a second cohort, we investigated risk factors and selected cases with low predisposition to sink. We used a case-control study with 86 cases divided by the outcomes: sinking grade II / III or grade 0 / I. Demographic, pathological and surgical data were analyzed. A score of factors correlated with sinking was tested. Results: In the first study, we found that sags of more advanced degrees were found in the 18mm group (p = 0.01). The event was detected at the point six weeks after surgery and did not progress significantly. The occurrence of more advanced degrees was correlated with transient low back pain at the six-week point. At the last point of analysis, we observed that in the 22mm group, 14% of the cases had grade II / III dip as opposed to 30% in the 18mm group. In the second study, the following risk factors were correlated with sinking group II / III: spondylolisthesis (92% vs 21%, p <0.001); Scoliosis (33% vs 12%, p = 0.033); Female (75% vs 42%, p = 0.007); Age (57.3 vs 67.7, p <0.001). These factors were used in a score (from 0-4) to assess the risk of each case. Scores ?2 were predictors of sinking with 92% sensitivity and 72% specificity. Conclusions: The occurrence of sinking is precocious, it should be carefully evaluated at the beginning of the follow-up because it reflects clinically and in loss of surgical correction. The use of wider spacers may decrease the occurrence. In addition, in the selection of eligible cases using predictive sinking factors found the probability of favorable evolution is 98%.
- ItemAcesso aberto (Open Access)Localização radioguiada de lesões mamárias impalpáveis orientada por ressonância magnética e pesquisa simultânea de linfonodo sentinela(Universidade Federal de São Paulo (UNIFESP), 2015-12-31) Docema, Marcos Fernando de Lima [UNIFESP]; Nazario, Afonso Celso Pinto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Background: Radio-guided occult lesion localization is a valid technique for the diagnosis of suspicious non-palpable lesions. Here we determine the feasibility of pre-operative localization of occult suspect non-palpable breast lesions using radio-guided occult lesion localization, as well as for identifying the sentinel lymph node. Methods: This is a descriptive study of data collected retrospectively. Pre-operative mapping of 34 breast lesions in 25 patients suspected of being malignant was performed using conventional imaging methods with a magnetic resonance imaging-guided radiopharmaceutical injection. Results: The mean time required to perform the localization was 25 minutes. After resection of the lesions using a gamma probe, malignancy was confirmed in fifteen patients (60.0%), with nine invasive ductal carcinomas, two invasive lobular carcinomas, and four in situ ductal carcinomas The resection was confirmed by the complete removal of the radioactive material. The pathologic results and images were concordant in all but two cases, which were submitted for new magnetic resonance imaging examinations and surgery that confirmed the malignancies. Of the 15 patients with confirmed malignancies, 10 had sentinel lymph node resection. Of these, eight were negative for metastasis, one had micro metastasis and one had confirmed metastasis. Three patients had full axillary node dissection, with metastasis found in only one. No side effects were observed with magnetic resonance-guided radiopharmaceutical injection. Conclusions: The sentinel node occult lesion localization technique is a simple, reproducible and effective alternative approach to occult lesions compared to other methods, such as mammotomy and the hook-wire localization technique, for mapping suspect breast lesions and identifying lymph node metastasis.
- ItemSomente MetadadadosMagnetofecção mediada por nanopartículas de óxido de ferro em tumores de glioblastoma para posterior aplicação terapêutica da magneto hipertermia: estudos in vitro e in vivo(Universidade Federal de São Paulo (UNIFESP), 2015-12-18) Aguiar, Marina Fontes de Paula [UNIFESP]; Contreras, Lionel Fernel Gamarra Contreras [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: Elucidate the in vitro and in vivo magnetofection process in glioblastoma tumors induced by C6 cells, with future perspective for therapeutic application of magneto hyperthermia. Therefore, superparamagnetic iron oxide nanoparticles conjugated with fluorescent Rhodamine-B molecules were used along with an external magnetic field for active tumor targeting. Methods: For magnetofection process, a resistive electromagnet capable of generating a variable magnetic field and pole geometry able to create a magnetic field gradient, was built. Previous in vitro tests with 50 nm hydrodynamic size NOFRhod were made to verify the transport and specific local accumulation. For in vivo targeting, the magnetic field of the poles was adjusted to 0 T (control) or 1,3 T (experimental value) and the nanoparticles were administrated by three different routes: tumor local, tail vein or carotid artery. Results: At first, we demonstrated that nanoparticles in this study are stable in DMEM culture medium and when dispersed in saline or PBS at a concentration of 50 µgFe/mL. The cell labeling analysis by prussian blue and fluorescent microscopy showed that NOF-Rhod are efficient for this purpose in all used concentrations (1, 10, 30 e 50 ug/mL), being enhanced by external magnetic field application. Besides that, cytotoxicity assay showed that cell death caused by these nanoparticles was barely evident. The volumetry study by MRI and histology demonstrated that in all used concentrations the tumor growth was evident and proportional both according to the day and the C6 cell concentration (104 , 105 ou 106 ). The in vitro tests showed that nanoparticle aggregation was efficient in all magnetic field gradients used. Moreover, the oblique steel pole addition created a punctual nanoparticle accumulation in one hose?s side, being this artifice selected for subsequent in vivo studies. The MRI monitoring was effective for NOF-Rhod identification in tumor region after local administration, showed an important signal reduction. The MRI sensibility, moreover, was not able to detect NOF-Rhod in tumor region after tail vein or carotid administration, further studies for these administration parameters are required. The in vivo magnetofection process analysis by histology, however, demonstrated more sensibility than MRI, evidencing iron concentration in tumor after the three NOFRhod administration routes. Furthermore, targeting intravenous administration with an external magnetic field was capable to increasing nanoparticle accumulation in tumor region. Conclusion: Taken together, our in vitro and in vivo results showed the NOF-Rhod magnetic targeting efficience, being this strategy a promisse tool for further applications of magneto hyperthermia technique.
- ItemSomente MetadadadosPrevalência de cistos pancreáticos incidentais à ressonância magnética de 3 tesla(Universidade Federal de São Paulo (UNIFESP), 2014-02-26) Oliveira, Patricia Bedesco de [UNIFESP]; Goldman, Suzan Menasce Goldman [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objetivos: determinar a prevalência de cistos pancreáticos detectados incidentalmente na ressonância magnética do abdome e correlacionar com a faixa etária e o gênero do paciente. Métodos: análise retrospectiva de 2.678 laudos de pacientes que fizeram ressonância magnética do abdome entre janeiro de 2012 e junho de 2013. Foram excluídos os pacientes com antecedente de doença ou cirurgia pancreática, avaliando-se a presença de cistos pancreáticos nos 2.583 pacientes restantes. Esse resultado foi correlacionado com dados demográficos dos pacientes (sexo e idade). Resultados: cistos pancreáticos incidentais estavam presentes em 9,3% (239/2.583) dos pacientes. A prevalência de cistos de pâncreas aumentou com a idade (p<0,0001). Não houve diferença estatisticamente significante entre pacientes do gênero masculino e feminino com relação à prevalência (p=0,588). Conclusões: a prevalência de cistos pancreáticos incidentais detectados à ressonância magnética é de 9,3% e aumenta com a idade. Não está relacionada com o gênero do paciente.
- ItemAcesso aberto (Open Access)Ressonância magnética na mielopatia associada ao HTLV-I: Leucoencefalopatia e atrofia medular(Academia Brasileira de Neurologia - ABNEURO, 1997-01-01) Ferraz, Ana Claudia; Gabbai, Alberto Alain [UNIFESP]; Abdala, Nitamar [UNIFESP]; Nogueira, Roberto Gomes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Cerebral white matter lesions and spinal cord atrophy have been frequently reported in patients with HTLV-I associated myelopathy (HAM). The exact frequency and the clinical relevance of these findings still remain to be elucidated. Twenty-nine patients with HAM were studied by magnetic resonance imaging of the brain and spine. Cerebral white matter lesions equal or over 3 mm in diameter were considered abnormal. The spinal cord size was evaluated using an index we have called spinal cord index. The radiological findings were correlated to the clinical features of the myelopathy. Cerebral white matter lesions occurred in 52% of the patients, and spinal cord atrophy in 74%. There was no significant correlation between these abnormalities and the clinical features studied. These findings suggest that the resonance imaging is a useful method for detection of cerebral and spinal cord abnormalities in HAM patients. The absence of correlation between cerebral white matter lesions and either patient age or risk factors for cardiovascular disease suggests a possible association between the leukoencephalopathy and the infection.