RESUMO
BACKGROUND AND PURPOSE: Although Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) has been introduced as an alternative to conventional voxel-based morphometry, there are scant data available regarding the optimal image-processing settings. The aim of this study was to optimize image-processing and ROI settings for the diagnosis of Alzheimer disease using DARTEL. MATERIALS AND METHODS: Between May 2002 and August 2014, we selected 158 patients with Alzheimer disease and 198 age-matched healthy subjects; 158 healthy subjects served as the control group against the patients with Alzheimer disease, and the remaining 40 served as the healthy data base. Structural MR images were obtained in all the participants and were processed using DARTEL-based voxel-based morphometry with a variety of settings. These included modulated or nonmodulated, nonsmoothed or smoothed settings with a 4-, 8-, 12-, 16-, or 20-mm kernel size. A z score was calculated for each ROI, and univariate and multivariate logistic regression analyses were performed to determine the optimal ROI settings for each dataset. The optimal settings were defined as those demonstrating the highest χ2 test statistics in the multivariate logistic regression analyses. Finally, using the optimal settings, we obtained receiver operating characteristic curves. The models were verified using 10-fold cross-validation. RESULTS: The optimal settings were obtained using the hippocampus and precuneus as ROIs without modulation and smoothing. The average area under the curve was 0.845 (95% confidence interval, 0.788-0.902). CONCLUSIONS: We recommend using the precuneus and hippocampus as ROIs without modulation and smoothing for DARTEL-based voxel-based morphometry as a tool for diagnosing Alzheimer disease.
Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Doença de Alzheimer/patologia , Encéfalo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROCAssuntos
Oxirredutases do Álcool/genética , Encefalopatias Metabólicas Congênitas/tratamento farmacológico , Encefalopatias Metabólicas/tratamento farmacológico , Cromossomos Humanos Par 14/genética , Predisposição Genética para Doença/genética , Lisina/metabolismo , Adulto , Fatores Etários , Oxirredutases do Álcool/urina , Encéfalo/enzimologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/fisiopatologia , Carnitina/uso terapêutico , Feminino , Flavina-Adenina Dinucleotídeo/uso terapêutico , Marcadores Genéticos/genética , Homozigoto , Humanos , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/genética , Deficiência Intelectual/fisiopatologia , Imageamento por Ressonância Magnética , Transtornos dos Movimentos/tratamento farmacológico , Transtornos dos Movimentos/genética , Transtornos dos Movimentos/fisiopatologia , Resultado do TratamentoRESUMO
Anti-muscle-specific receptor tyrosine kinase (MuSK) antibody-positive myasthenia gravis (MG) patients show various responses to conventional immunosuppressive treatment and some patients are resistant to these therapies. We report a 50-year-old Japanese man with anti-MuSK antibody-positive MG, who showed no or poor response to various therapies, including plasmapheresis, corticosteroid, and tacrolimus. The patient was then treated with intravenous immunoglobulin (IVIG), and showed a good response that persisted over 20 months. The outcome of this case suggests that IVIG treatment may be an effective therapeutic option for anti-MuSK antibody-positive MG, with a potentially long-term effect.