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1.
Mol Imaging Radionucl Ther ; 21(2): 56-62, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23486848

RESUMO

OBJECTIVE: The aim of this study was to demonstrate the functional compensation that occurs in kidneys which accompany a partner with total or partial loss of renal functioning mass, using camera-based Tc 99m MAG3 clearance technique. MATERIAL AND METHODS: Eighty five patients (43M, 42F, age: 44.8±12.6, range: 18-77 years) with normal serum creatinine levels and normal (

2.
Eur J Nucl Med Mol Imaging ; 37(11): 2070-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20585773

RESUMO

PURPOSE: Quantification of myocardial perfusion scintigraphy is frequently performed to assist physicians in detecting coronary artery disease (CAD). Software packages provide automated quantification of perfusion data. We aimed to compare the three commonly used software packages, Emory Cardiac Toolbox (ECT v2 and ECT v3), 4D-MSPECT (4DM v2 and 4DM v4) and Quantitative Perfusion SPECT (QPS v3 and QPS v4). METHODS: We selected 283 patients who had a myocardial perfusion scintigraphy with (201)Tl followed by coronary angiography within 3 months. Summed stress score (SSS), summed difference score (SDS), total stress defect extent (TDE) and regional stress defect extent values were obtained from programs. A ≥70% stenosis in coronary arteries and their major branches was considered positive for CAD. A subgroup of patients was used to form an institutional normal database for QPS and 4DM. Receiver-operating characteristic (ROC) analysis to detect CAD was performed. RESULTS: Mean SSS ± SD (vendor) for ECT v3, QPS v4 and 4DM v4 were 9.2 ± 7.1, 10.1 ± 6.8 and 5.5 ± 6.1, respectively. Area under the curve (AUC) values of SSS ROC analysis were 0.738 ± 0.031 for QPS v3, 0.755 ± 0.030 for QPS v4, 0.758 ± 0.030 for ECT v2, 0.778 ± 0.029 for ECT v3 and 0.771 ± 0.030 for 4DM v4. The AUC values for TDE were 0.755 ± 0.030 for QPS v4, 0.769 ± 0.030 for ECT v3 and 0.775 ± 0.029 for 4DM v4. The differences were not significant for both SSS and TDE. Differences of AUC between regional stress defect extent values of programs and AUC of SSS between institutional and vendor normal databases were not significant. CONCLUSION: The diagnostic performances of programs to detect CAD are similar. However, there are differences in the magnitudes of the quantitative values produced by the programs.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Imagem de Perfusão do Miocárdio/métodos , Software , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Estresse Fisiológico/efeitos dos fármacos , Tomografia Computadorizada de Emissão de Fóton Único
3.
J Nucl Cardiol ; 17(3): 405-13, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20204564

RESUMO

BACKGROUND: The purpose of this study is to develop and analyze an open-source artificial intelligence program built on artificial neural networks that can participate in and support the decision making of nuclear medicine physicians in detecting coronary artery disease from myocardial perfusion SPECT (MPS). METHODS AND RESULTS: Two hundred and forty-three patients, who had MPS and coronary angiography within three months, were selected to train neural networks. Six nuclear medicine residents, one experienced nuclear medicine physician, and neural networks evaluated images of 65 patients for presence of coronary artery stenosis. Area under the curve (AUC) of receiver operating characteristics analysis for networks and expert was .74 and .84, respectively. The AUC of the other physicians ranged from .67 to .80. There were no significant differences between expert, neural networks, and standard quantitative values, summed stress score and total stress defect extent. CONCLUSIONS: The open-source neural networks developed in this study may provide a framework for further testing, development, and integration of artificial intelligence into nuclear cardiology environment.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Redes Neurais de Computação , Tomografia Computadorizada de Emissão de Fóton Único , Inteligência Artificial , Angiografia Coronária , Teste de Esforço , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio
4.
Turk Psikiyatri Derg ; 20(4): 346-56, 2009.
Artigo em Turco | MEDLINE | ID: mdl-20013426

RESUMO

OBJECTIVE: Functional changes in the brains of autistic children due to risperidone treatment and theirs relationship to the symptom clusters are yet unknown. In this autistic disorder case series we aimed to comparatively evaluate the clinical findings before and after risperidone treatment, and regional cerebral blood flow (rCBF) findings with 99mTc-hexamethylpropyleneamine oxime (HMPAO) brain SPECT. METHOD: Eleven autistic patients (age range: 6-7 years; 4 girls, 7 boys) received risperidone therapy (1.5-2.5 mg d(-1)) and were followed-up for 3 months. All the patients underwent neurologic examinations, psychometric examinations, and SPECT imaging, both at the start of risperidone treatment and 3 months after the treatment started. Clinical observations, and the observations of parents and teachers were recorded. These results were compared with cerebral perfusion indices obtained from SPECT data. RESULTS: After 3 months of treatment changes in rCBF were observed in various regions and to varying degrees. We observed relationships between clinical symptoms and pre-therapy rCBF findings, and between clinical improvement and rCBF changes. CONCLUSION: Findings in the present case series are the first to demonstrate a relationship between clinical improvement and regional perfusion patterns after risperidone treatment. We think that these findings may contribute to the understanding of the neurofunctional mechanisms and hypothetical models of autism.


Assuntos
Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/fisiopatologia , Circulação Cerebrovascular/fisiologia , Risperidona/uso terapêutico , Antipsicóticos/uso terapêutico , Transtorno Autístico/diagnóstico por imagem , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/efeitos da radiação , Criança , Corpo Caloso/irrigação sanguínea , Feminino , Seguimentos , Humanos , Masculino , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Fluxo Sanguíneo Regional/efeitos da radiação , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único
5.
Clin Nucl Med ; 33(5): 365-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18431160

RESUMO

A 49-year-old man presented with a left nasal cavity mass, biopsy of which revealed extranodal NK/T cell lymphoma. A PET-CT scan showed increased F-18 FDG uptake in the nasal mass, anterior mediastinal lymph nodes, and multiple subcutaneous nodular deposits in the chest wall, gluteal region, and right femoral areas. The patient achieved complete remission with salvage l-asparaginase therapy after failing first-line standard anthracycline-based chemotherapy. PET-CT was very useful in detecting subcutaneous nodules consistent with widespread dissemination. There is limited literature data on the use of the PET scan in the diagnosis and staging of extranodal nasal NK/T-cell lymphomas. Our case highlights the important role of F-18 FDG PET in the staging of these patients.


Assuntos
Fluordesoxiglucose F18 , Linfoma Extranodal de Células T-NK/diagnóstico por imagem , Neoplasias Nasais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos
6.
J Child Neurol ; 19(5): 387-90, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15224712

RESUMO

Group A streptococcal infections cause a wide range of neuropsychiatric disorders, such as Sydenham's chorea, tics, obsessive-compulsive disorders, and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). Structural (computed tomography and magnetic resonance imaging) and functional (positron emission tomography, single-photon emission computed tomography) imaging studies in patients with Sydenham's chorea have suggested reversible striatal abnormalities. The objective of this study was to investigate the cerebral perfusion patterns of the subcortical structures by using hexamethylpropylenamine oxime single-photon emission computed tomography (HMPAO-SPECT) in seven cases of Sydenham's chorea and two cases of streptococcal tic disorder. HMPAO-SPECT studies revealed a hyperperfusion pattern in two and a hypoperfusion pattern in five of the chorea patients and in two patients with tic disorder. The results are discussed in relation to the duration and severity of the symptoms and the response to therapy. Functional imaging findings can be variable in Sydenham's chorea, and hyperperfusion of the striatum and thalamus could be an indicator of the response to therapy and the severity of symptoms. However, the number of cases so far investigated by either SPECT or positron emission tomography is still too limited to draw any firm conclusions.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Coreia/diagnóstico , Infecções Estreptocócicas/complicações , Streptococcus pyogenes , Transtornos de Tique/diagnóstico , Adolescente , Encéfalo/fisiopatologia , Circulação Cerebrovascular , Criança , Coreia/etiologia , Coreia/fisiopatologia , Feminino , Humanos , Masculino , Cintilografia , Transtornos de Tique/etiologia , Transtornos de Tique/fisiopatologia
7.
Pediatr Int ; 46(6): 711-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15660872

RESUMO

BACKGROUND: The diagnosis of brain death is based on both clinical and laboratory findings. However, diagnosis of brain death is still contentious and reliable tests are required. Early recognition and declaration of the diagnosis is the main goal, which is important for discontinuation of life support and organ donation for transplantation. In order to achieve this goal, competent diagnostic procedures should be performed. In this paper the authors review the diagnosis of brain death in eight children from different age groups, with an emphasis on factors concerning the reliability, use and appropriate application time of Tc-99m-HMPAO single photon emission computed tomography (SPECT) in early diagnosis in infants and newborns. METHODS: Eight patients who fulfilled the clinical criteria of brain death underwent Tc-99m HMPAO SPECT and electroencephalogram (EEG) monitoring. RESULTS: All patients had electrocerebral silence on EEG recordings. Six patients showed lack of perfusion in cerebrum in their first SPECT, however, newborns needed a second image for a confirmed diagnosis. CONCLUSION: In infants, SPECT has a high reliability for confirmed diagnosis of brain death; however, in newborns the application time is important for an accurate diagnosis.


Assuntos
Morte Encefálica/diagnóstico por imagem , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único , Morte Encefálica/diagnóstico , Criança , Pré-Escolar , Eletroencefalografia/métodos , Feminino , Humanos , Recém-Nascido , Masculino , Estudos de Amostragem , Sensibilidade e Especificidade
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