Your browser doesn't support javascript.
loading
Twice-refocused stimulated echo diffusion imaging: Measuring diffusion time dependence at constant T1 weighting.
Martin, Jan; Endt, Sebastian; Wetscherek, Andreas; Kuder, Tristan Anselm; Doerfler, Arnd; Uder, Michael; Hensel, Bernhard; Laun, Frederik Bernd.
Afiliación
  • Martin J; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
  • Endt S; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
  • Wetscherek A; Department of Computer Science, Technical University of Munich, Garching, Germany.
  • Kuder TA; Joint Department of Physics, The Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, London, United Kingdom.
  • Doerfler A; Department Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany.
  • Uder M; Institute of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
  • Hensel B; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
  • Laun FB; Center for Medical Physics and Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Magn Reson Med ; 83(5): 1741-1749, 2020 05.
Article en En | MEDLINE | ID: mdl-31657868
PURPOSE: Diffusion times longer than 50 ms are typically probed with stimulated-echo sequences. Varying the diffusion time in stimulated-echo sequences affects the T1 weighting of subcompartments, complicating the analysis of diffusion time dependence. Although inversion recovery preparation could be used to change the T1 weighting, it cannot ensure equal T1 weighting at arbitrary mixing times. In this article, a sequence that ensures constant T1 weighting over a wide range of diffusion times is presented. METHODS: The proposed sequence features 2 independent longitudinal storage periods: TM1 and TM2 . Diffusion encoding is performed during TM1 , effectively coupling the diffusion time and TM1 . Equal T1 weighting at arbitrary diffusion times is realized by keeping the total mixing time TM1 + TM2 constant. The sequence was compared with conventional stimulated-echo measurements of diffusion in a 2-compartment phantom consisting of distilled water and paraffinum perliquidum. Additionally, in vivo DTI of the brain was carried out for 8 healthy volunteers with diffusion times ranging from 50 to 500 ms. RESULTS: Diffusion time dependence of the axial and radial diffusivity was detected in the brain. Both sequences resulted in almost identical diffusivities in white matter. In regions containing partial volumes of gray and white matter, a dependency on T1 weighting was observed. CONCLUSION: In accordance with previous studies, little variance of T1 values appeared to be present in healthy white matter. However, this is likely different in diseased tissue. Here, the proposed sequence can be effective in differentiating between diffusion time dependence and T1 weighting effects.
Asunto(s)
Palabras clave
Texto completo
Añadir a Mi BVS
Imprimir
XML
PubMed Links
Buscar en Google

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Asunto principal: Teofilina / Sustancia Blanca Límite: Humans Idioma: En Revista: Magn Reson Med Asunto de la revista: DIAGNOSTICO POR IMAGEM Año: 2020 Tipo del documento: Article País de afiliación: Alemania Pais de publicación: Estados Unidos
Texto completo
Añadir a Mi BVS
Imprimir
XML
PubMed Links
Buscar en Google

Texto completo: 1 Colección: 01-internacional Base de datos: MEDLINE Asunto principal: Teofilina / Sustancia Blanca Límite: Humans Idioma: En Revista: Magn Reson Med Asunto de la revista: DIAGNOSTICO POR IMAGEM Año: 2020 Tipo del documento: Article País de afiliación: Alemania Pais de publicación: Estados Unidos