23 results

Iron overload in a teenager with xerocytosis: the importance of nuclear magnetic resonance imaging

Reijâne Alves de Assis, Carolina Kassab, Fernanda Salles Seguro, Fernando Ferreira Costa, Paulo Augusto Achucarro Silveira, John Wood, [...]

DOI: 10.1590/S1679-45082013000400022

To report a case of iron overload secondary to xerocytosis, a rare disease in a teenager, diagnosed, by T2* magnetic resonance imaging. We report the case of a symptomatic patient with xerocytosis, a ferritin level of 350ng/mL and a significant cardiac iron overload. She was diagnosed by T2* magnetic resonance imaging and received chelation therapy Ektacytometric analysis confirmed the diagnosis of hereditary xerocytosis. Subsequent T2* magnetic resonance imaging demonstrated complete resolution of the iron overload in various organs, as a […]

High correlation between microbubble contrast-enhanced ultrasound, magnetic resonance and histopathology in the evaluation of hepatocellular carcinoma

Marcos Roberto Gomes de Queiroz, Miguel José Francisco Neto, Rodrigo Gobbo Garcia, Antonio Rahal Junior, Paolo Salvalaggio, Marcelo Buarque de Gusmão Funari

DOI: 10.1590/S1679-45082013000400017

OBJECTIVES:To evaluate the efficacy of microbubble contrast ultrasound in diagnosis of hepatocellular carcinoma and to compare its results with those of magnetic resonance and histopathology.METHODS:A total of 29 patients suffering from chronic liver diseases and awaiting liver transplants at Hospital Israelita Albert Einstein were subject to magnetic resonance, microbubble contrast ultrasound, and excision liver biopsies.RESULTS:Excellent agreement between magnetic resonance and microbubble contrast ultrasound was observed in this study. There was moderate agreement between both imaging methods and histopathology results.CONCLUSION:Microbubble contrast […]

Endometrium evaluation with high-field (3-Tesla) magnetic resonance imaging in patients submitted to uterine leiomyoma embolization

Monica Amadio Piazza Jacobs, Felipe Nasser, Eduardo Zlotnik, Marcos de Lorenzo Messina, Ronaldo Hueb Baroni

DOI: 10.1590/S1679-45082013000100011

Objective:To evaluate the endometrial alterations related to embolization of uterine arteries for the treatment of symptomatic uterine leiomyomatosis (pelvic pain and/or uterine bleeding) by means of high-field (3-Tesla) magnetic resonance.METHODS:This is a longitudinal and prospective study that included 94 patients with a clinical and imaging diagnosis of symptomatic uterine leiomyomatosis, all of them treated by embolization of the uterine arteries. The patients were submitted to evaluations by high-field magnetic resonance of the pelvis before and 6 months after the procedure. […]

Intermediate pilomyxoid astrocytoma and diencephalic syndrome: imaging findings

Olavo Kyosen Nakamura, Marco da Cunha Pinho, Vicente Odone Filho, Sergio Rosemberg

DOI: 10.1590/S1679-45082012000200020

Pilomyxoid astrocytoma, an entity described as a histological variant of pilocytic astrocytoma, is a rare primary tumor of the central nervous system. It is usually located in the hypothalamic-chiasmatic area, affecting children with a mean age of 10 months. It has a high rate of recurrence and cerebrospinal fluid dissemination, which may be present throughout the neuroaxis. Due to its topography, it may present developmental delay in childhood and diencephalic syndrome, characterized by extreme weight loss, lack of fat accumulation, […]

Intracellular labeling and quantification process by magnetic resonance imaging using iron oxide magnetic nanoparticles in rat C6 glioma cell line

Javier Bustamante Mamani, Lorena Favaro Pavon, Liza Aya Mabuchi Miyaki, Tatiana Tais Sibov, Fabiana Rossan, Paulo Henrique Silveira, [...]

DOI: 10.1590/S1679-45082012000200016

Objective:To assess intracellular labeling and quantification by magnetic resonance imaging using iron oxide magnetic nanoparticles coated with biocompatible materials in rat C6 glioma cells in vitro. These methods will provide direction for future trials of tumor induction in vivo as well as possible magnetic hyperthermia applications.METHODS:Aminosilane, dextran, polyvinyl alcohol, and starch-coated magnetic nanoparticles were used in the qualitative assessment of C6 cell labeling via light microscopy. The influence of the transfection agent poly-L-lysine on cellular uptake was examined. The quantification […]

Computerized brain tumor segmentation in magnetic resonance imaging

Maryana de Carvalho Alegro, Edson Amaro Junior, Rosei de Deus Lopes

DOI: 10.1590/S1679-45082012000200008

Objective:To propose an automatic brain tumor segmentation system.METHODS:The system used texture characteristics as its main source of information for segmentation.RESULTS:The mean correct match was 94% of correspondence between the segmented areas and ground truth.CONCLUSION:Final results showed that the proposed system was able to find and delimit tumor areas without requiring any user interaction.

In vivo magnetic resonance imaging tracking of C6 glioma cells labeled with superparamagnetic iron oxide nanoparticles

Javier Bustamante Mamani, Jackeline Moraes Malheiros, Ellison Fernando Cardoso, Alberto Tannús, Paulo Henrique Silveira, Lionel Fernel Gamarra

DOI: 10.1590/S1679-45082012000200009

Objective:The aim of the current study was to monitor the migration of superparamagnetic iron oxide nanoparticle (SPION)-labeled C6 cells, which were used to induce glioblastoma tumor growth in an animal model, over time using magnetic resonance imaging (MRI), with the goal of aiding in tumor prognosis and therapy.METHODS:Two groups of male Wistar rats were used for the tumor induction model. In the first group (n=3), the tumors were induced via the injection of SPION-labeled C6 cells. In the second group […]

Seeking tools for image fusion between computed tomography, structural and functional magnetic resonance methods for applications in neurosurgery

Liana Guerra Sanches da Rocha, Edson Amaro Junior

DOI: 10.1590/S1679-45082012000200007

Objective:To evaluate tools for the fusion of images generated by tomography and structural and functional magnetic resonance imaging.METHODS:Magnetic resonance and functional magnetic resonance imaging were performed while a volunteer who had previously undergone cranial tomography performed motor and somatosensory tasks in a 3-Tesla scanner. Image data were analyzed with different programs, and the results were compared.RESULTS:We constructed a flow chart of computational processes that allowed measurement of the spatial congruence between the methods. There was no single computational tool that […]

Manganese-enhanced magnetic resonance imaging in the acute phase of the pilocarpine-induced model of epilepsy

Jackeline Moraes Malheiros, Beatriz Monteiro Longo, Alberto Tannús, Luciene Covolan

DOI: 10.1590/S1679-45082012000200023

Magnetic resonance images are useful in the study of experimental models of temporal lobe epilepsy. The manganese-enhanced MRI (MEMRI) technique is of interest since it combines the effects caused by manganese on the increased contrast in activated cell populations, when competing with calcium in synaptic transmission. Thus, the purpose of this study was to investigate the temporal evolution of the contrast related to manganese in the acute phase of temporal lobe epilepsy induced by systemic pilocarpine and compare it to […]

Tumor growth analysis by magnetic resonance imaging of the C6 glioblastoma model with prospects for the assessment of magnetohyperthermia therapy

André César da Silva, Francisco Romero Cabral, Javier Bustamante Mamani, Jackeline Moraes Malheiros, Roberson Saraiva Polli, Alberto Tannus, [...]

DOI: 10.1590/S1679-45082012000100004

Objective:The objective was to establish a pattern of tumor growth of the C6 model of glioblastoma multiform in Wistar rats via magnetic resonance imaging (MRI) for the subsequent verification of tumor volume reduction due to magnetic hyperthermia therapy.METHODS:Young male Wistar rats weighing between 250 and 300 g were used for the C6 model. After the rates were anesthetized (55 mg/kg ketamine and 11 mg/kg xylazine), C6 lineage tumorigenic cells suspended in culture medium (10(5) cells in 10 µl) were stereotaxically […]

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