Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Eur J Radiol ; 155: 110493, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36027759

RESUMO

PURPOSE: We tested a novel multi-parametric (mp) whole body (WB)-MRI evaluation algorithm for medullary lesions in comparison to positron emission tomography (PET) radiotracers 18F-fluorodeoxyglucose (18F-FDG) and 11C-methionine (11C-MET). METHODS AND MATERIALS: This retrospective single-center study included 44 MM patients, who received both 18F-FDG-PET and WB-MRI within ten days. MRI classified focal lesions as vital when showing 1) significant diffusion-restriction, 2) a fat fraction (FF) less than 20 % and 3) homogenous hypointensity on T2-weighted images. On a lesion-by-lesion level the findings were compared to 18F-FDG PET by using a 5-point scoring system (analogous to the Deauville score [DS]). In 24/44 (55 %) patients additional comparison to 11C-MET PET was available. RESULTS: Among two radiologists, an excellent inter-observer reliability for mpWB-MRI in a total of 84 medullary lesions was observed (ICC = 1, k = 1, p <.01). 16/17 (94.1 %) MRI-classified vital lesions had a DS of 4 or 5 on either 18F-FDG-PET or 11C-MET-PET. MRI-rated non-vital lesions correlated with PET-based DS ≤ 3. When results of mpWB-MRI were compared to 18F-FDG, a fair inter-observer agreement was recorded (ICC = 0.52, k = 0.53, p <.01), while for 11C-MET, an excellent concordance rate was achieved (ICC = 0.81, k = 0.79, p <.01). CONCLUSION: The proposed mpWB-MRI interpretation algorithm allowed to assess tumor activity of myeloma lesions with high inter-observer reproducibility. We observed a substantial concordance between the mpWB-MRI classification of lesions and PET assessment based on a semi-automatically calculated 5-point scoring system analogous to the Deauville scores.


Assuntos
Fluordesoxiglucose F18 , Mieloma Múltiplo , Humanos , Imageamento por Ressonância Magnética/métodos , Metionina , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Racemetionina , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
2.
Acad Radiol ; 29(1): e1-e8, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139155

RESUMO

RATIONALE AND OBJECTIVES: Our study compared sensitivity, specificity, and accuracy of whole-body diffusion-weighted imaging (WB-DWI) using a b-value of 2000 s/mm2 with that of the commonly used b-value of 800 s/mm2 for depiction of active tumor sites in patients with plasma cell diseases. We introduced an ultrahigh b-value to reduce interfering signals from benign and post-therapeutic inactive lesions by suppressing T2-shine-through effects. MATERIALS AND METHODS: The prospective single-center study included patients when they went through a whole-body MRI (WB-MRI) staging or response evaluation procedure. The apparent diffusion coefficient (ADC) and morphologic appearance served as reference for classifying focal lesions on WB-DWI as vital or post-therapeutic. Additionally, we compared our classification with patients' serological markers of disease activity. RESULTS: One hundred participants (65 ± 10 years, 58 men) underwent WB-DWI between June and October 2019. The detection rate of vital focal lesions was similar for both b-values with a sensitivity of 0.99 using b = 800 s/mm2 and 0.98 using b = 2000 s/mm2. By contrast, specificity and accuracy were 0.09 and 0.71 when using a b-value of 800 s/mm2, and 0.96 and 0.98 when using a b-value of 2000 s/mm2, respectively. The difference in specificity and accuracy was statistically significant (p < 0.001). CONCLUSION: Using a b-value of 2000 s/mm2 significantly improved the specificity of lesion detection with WB-DWI as compared to the commonly used b-value of 800 s/mm2. The high b-value significantly reduced signal intensities of post-therapeutic or benign lesions and provided a significantly more accurate representation of active tumor load.


Assuntos
Paraproteinemias , Imagem Corporal Total , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
3.
J Occup Health Psychol ; 19(1): 18-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24447218

RESUMO

This study examined how achievement goals interact with autonomy to explain mastery of a challenging career transition. In a sample of women who were returning from maternity leave, we examined how autonomy interacted with achievement goals to explain two types of outcomes: effective functioning (i.e., self-rated work adjustment, coworker-rated work adjustment, and coworker-rated learning competence) and well-being at work (i.e., positive affect and life satisfaction). In a longitudinal design (249 employees), we found that achievement goals and autonomy had direct effects on successful return to work. Moreover, maladaptive motivational states hindered the effective use of workplace resources: Autonomy moderated the consequences associated with performance-prove and -avoidance goals. Among those who adopted performance-prove goals, autonomy improved work adjustment and learning. However, women who adopted performance-avoidance goals experienced a trade-off between effective functioning and well-being, when equipped with high autonomy.


Assuntos
Logro , Mobilidade Ocupacional , Objetivos , Satisfação no Emprego , Licença Parental , Autonomia Profissional , Competência Profissional , Meio Social , Adaptação Psicológica , Adulto , Feminino , Humanos , Individualidade , Estudos Longitudinais , Motivação , Adulto Jovem
4.
J Appl Psychol ; 94(2): 353-70, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19271795

RESUMO

This meta-analysis explores agreement in self- and supervisory ratings of job performance (k = 128 independent samples). It suggests a 3-stage model of the rating process and reviews the empirical evidence for the relevance of each of these 3 stages to an understanding of agreement in ratings. The proposed 3-stage model serves as the guiding rationale for the examination of an extensive set of variables that moderate rater agreement. Results are reported for 2 indicators of rater agreement (correlational and mean-level agreement). Self-supervisor ratings yielded an overall correlation of .22 (rho = .34; k = 115; n = 37,752). Position characteristics and the use of nonjudgmental performance indicators were the main moderators. Leniency in self-ratings is indicated by higher mean levels of self-ratings compared with supervisory ratings. Within Western samples, performance self-ratings showed leniency (d = 0.32, Delta = .49; k = 89; n = 35,417) dependent on contextual features, scale format, and scale content.


Assuntos
Avaliação de Desempenho Profissional/estatística & dados numéricos , Autoimagem , Comunicação , Sinais (Psicologia) , Humanos , Modelos Estatísticos , Variações Dependentes do Observador , Objetivos Organizacionais , Gestão de Recursos Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA