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1.
Molecules ; 25(20)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33086589

RESUMO

Single photon emission computed tomography (SPECT) has been employed to detect Parkinson's disease (PD). However, analysis of the SPECT PD images was mostly based on the region of interest (ROI) approach. Due to limited size of the ROI, especially in the multi-stage classification of PD, this study utilizes deep learning methods to establish a multiple stages classification model of PD. In the retrospective study, the 99mTc-TRODAT-1 was used for brain SPECT imaging. A total of 202 cases were collected, and five slices were selected for analysis from each subject. The total number of images was thus 1010. According to the Hoehn and Yahr Scale standards, all the cases were divided into healthy, early, middle, late four stages, and HYS I~V six stages. Deep learning is compared with five convolutional neural networks (CNNs). The input images included grayscale and pseudo color of two types. The training and validation sets were 70% and 30%. The accuracy, recall, precision, F-score, and Kappa values were used to evaluate the models' performance. The best accuracy of the models based on grayscale and color images in four and six stages were 0.83 (AlexNet), 0.85 (VGG), 0.78 (DenseNet) and 0.78 (DenseNet).


Assuntos
Encéfalo/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Doença de Parkinson/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Encéfalo/fisiopatologia , Corpo Estriado/fisiopatologia , Aprendizado Profundo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Doença de Parkinson/classificação , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Estudos Retrospectivos , Tecnécio/uso terapêutico
2.
Sensors (Basel) ; 19(7)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30978990

RESUMO

The neuroimaging techniques such as dopaminergic imaging using Single Photon Emission Computed Tomography (SPECT) with 99mTc-TRODAT-1 have been employed to detect the stages of Parkinson's disease (PD). In this retrospective study, a total of 202 99mTc-TRODAT-1 SPECT imaging were collected. All of the PD patient cases were separated into mild (HYS Stage 1 to Stage 3) and severe (HYS Stage 4 and Stage 5) PD, according to the Hoehn and Yahr Scale (HYS) standard. A three-dimensional method was used to estimate six features of activity distribution and striatal activity volume in the images. These features were skewness, kurtosis, Cyhelsky's skewness coefficient, Pearson's median skewness, dopamine transporter activity volume, and dopamine transporter activity maximum. Finally, the data were modeled using logistic regression (LR) and support vector machine (SVM) for PD classification. The results showed that SVM classifier method produced a higher accuracy than LR. The sensitivity, specificity, PPV, NPV, accuracy, and AUC with SVM method were 0.82, 1.00, 0.84, 0.67, 0.83, and 0.85, respectively. Additionally, the Kappa value was shown to reach 0.68. This claimed that the SVM-based model could provide further reference for PD stage classification in medical diagnosis. In the future, more healthy cases will be expected to clarify the false positive rate in this classification model.


Assuntos
Corpo Estriado/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Máquina de Vetores de Suporte , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Dopamina/química , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/química , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio/administração & dosagem , Doença de Parkinson/classificação , Doença de Parkinson/diagnóstico , Doença de Parkinson/patologia , Estudos Retrospectivos , Tropanos/administração & dosagem
3.
J Xray Sci Technol ; 23(2): 243-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25882734

RESUMO

Positron emission tomography (PET) had been utilized to image gene therapy, estimate tumor growth, detect neural function of the brain, and diagnose disease. However, sinogram noise always results inaccurate PET images. The factorial design of experiment (DOE), a statistical method, was applied to investigate, correct and estimate the fraction of scattering of 2D sinogram in PET. The DOE was included as factors of angle views and scatter media with two levels designed. The PET sinogram after scattering correction was then reconstructed by filtered back projection (FBP). Both Ge-68 uniform phantom and Jaszczak anthropomorphic torso phantom were applied to exam the performance of presented scattering correction algorithm. The signal-to-noise ratio (SNR), standard deviation (STD) of background, and full width at half maximum (FWHM), and uniformity test were applied to validate the performance of presented method. The proposed method provides a narrower FWHM, smaller STD of the background, higher SNR and better uniformity than those of original protocols. This method should be tested for accuracy and feasibility with three-dimensional phantoms or real animal studies and consideration effects of cross-talk between slices in future work.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Humanos , Modelos Biológicos , Imagens de Fantasmas
4.
Case Rep Hematol ; 2013: 351292, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24198983

RESUMO

Up to 40% of patients with advanced Hodgkin lymphoma (HL) become refractory or relapsed after current standard chemotherapy, among which primary refractory HL confers a particularly poor outcome. With intensive salvage chemotherapy and autologous stem cell transplantation, the long-term remission rate for these patients was only 30%, but more selective treatments with higher therapeutic index are needed. We report the experience of using a new anti-CD30 immunotoxin, brentuximab vedotin, in salvage treatment of a 30-year-old woman with primary refractory Hodgkin lymphoma. The patient presented with SVC syndrome due to the bulky mediastinal tumor and was confirmed to have classical Hodgkin lymphoma, nodular sclerosis type, stage IIIA. The tumor responded to induction chemotherapy transiently, but local progression was noted during subsequent cycles of treatment. Salvage radiotherapy to the mediastinal tumor, obtained no remission but was followed by rapid in-field progression and then lung metastasis. She declined stem cell transplantation and received salvage brentuximab vedotin (BV) therapy, which induced dramatic shrinkage of tumor without significant side effects. Serial followup of PET/CT imaging confirmed a rapid and continuous complete remission for 12 months. Although durability of the remission needs further observation, this case illustrates the excellent efficacy of brentuximab vedotin in primary refractory Hodgkin lymphoma.

5.
Int J Cardiovasc Imaging ; 29(5): 1039-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23515948

RESUMO

This study examines the utilization patterns of myocardial perfusion imaging (MPI) and cardiac catheterization (CC) under Taiwan's national health insurance program. This study used the longitudinal health insurance database with 1,000,000 people were randomly selected from the national health insurance research database. This study obtained data from these patients with coronary artery disease (CAD) and comparison with the utilization of MPI or CC between 2005 and 2009. The incidence of CAD did not significantly change, while the prevalence of CAD, utilization of MPI, and the utilization of CC for the CAD patients increased annually. There were the most CAD patients in Northern Taiwan (43.5%), followed by Southern, Central, and Eastern Taiwan. The utilizations of both of MPI (12.7 per 100 CAD patients) and CC (10.6 per 100 CAD patients) were most frequent in Northern Taiwan followed by Southern, Central, and Eastern Taiwan. However, the MPI/CC ratio was 1.20 in Northern Taiwan, followed by Southern, Central, and Eastern Taiwan (0.88, 0.64, and 0.52, respectively, P = 0.0008). The use of MPI was higher than CC only in Northern Taiwan. MPI may be underutilized to serve the role of gatekeeper for CC in the other regions.


Assuntos
Cateterismo Cardíaco/estatística & dados numéricos , Doença da Artéria Coronariana/diagnóstico , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Programas Nacionais de Saúde , Compostos Radiofarmacêuticos , Cobertura Universal do Seguro de Saúde , Cateterismo Cardíaco/tendências , Doença da Artéria Coronariana/epidemiologia , Bases de Dados Factuais , Humanos , Incidência , Modelos Lineares , Imagem de Perfusão do Miocárdio/tendências , Programas Nacionais de Saúde/tendências , Padrões de Prática Médica/tendências , Prevalência , Taiwan/epidemiologia , Fatores de Tempo , Cobertura Universal do Seguro de Saúde/tendências
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