Generalization of intravoxel incoherent motion model by introducing the notion of continuous pseudodiffusion variable.
Magn Reson Med
; 76(5): 1594-1603, 2016 11.
Article
en En
| MEDLINE
| ID: mdl-27747940
ABSTRACT
PURPOSE:
A generalized intravoxel incoherent motion (IVIM) model, called the GIVIM, was proposed to better account for complex perfusion present in the tissues having various vessels and flow regimes, such as the liver. THEORY ANDMETHODS:
The notions of continuous pseudodiffusion variable as well as perfusion fraction density function were introduced to describe the presence of multiple perfusion components in a voxel. The mean and standard deviation of Gaussian perfusion fraction density function were then used to define two new parameters, the mean pseudodiffusivity ( D¯) and pseudodiffusion dispersion (σ). The GIVIM model was evaluated by testing whether or not it can reflect hepatic perfusion difference caused by flow-compensated imaging sequences having different diffusion times. Also, D¯ was compared with D* in the standard IVIM model.RESULTS:
The values of both D* and D¯ decreased after flow compensation and further decreased when shortening diffusion time. D¯ exhibited reduced variance in comparison with D*. In addition, σ also showed its sensitivity to hepatic perfusion difference caused by the flow-compensated imaging sequences.CONCLUSION:
The GIVIM model has the ability to better describe multicomponent perfusion without lengthening acquisition time and knowing in advance the number and/or the variety of perfusion components. Magn Reson Med 761594-1603, 2016. © 2015 International Society for Magnetic Resonance in Medicine.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Interpretación de Imagen Asistida por Computador
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Angiografía por Resonancia Magnética
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Hígado
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Circulación Hepática
/
Modelos Biológicos
Tipo de estudio:
Diagnostic_studies
/
Evaluation_studies
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Prognostic_studies
/
Risk_factors_studies
Límite:
Humans
Idioma:
En
Revista:
Magn Reson Med
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2016
Tipo del documento:
Article
País de afiliación:
China