Spin-echo micro-MRI of trabecular bone using improved 3D fast large-angle spin-echo (FLASE).
Magn Reson Med
; 61(5): 1114-21, 2009 May.
Article
en En
| MEDLINE
| ID: mdl-19215044
ABSTRACT
Fast large-angle spin echo (FLASE) is a common pulse sequence designed for quantitative imaging of trabecular bone (TB) microarchitecture. However, imperfections in the nonselective phase-reversal pulse render it prone to stimulated echo artifacts. The problem is further exacerbated at isotropic resolution. Here, a substantially improved RF-spoiled FLASE sequence (sp-FLASE) is described and its performance is illustrated with data at 1.5T and 3T. Additional enhancements include navigator echoes for translational motion sensing applied in a slice parallel to the imaging slab. Whereas recent work suggests the use of fully-balanced FLASE (b-FLASE) to be advantageous from a signal-to-noise ratio (SNR) point of view, evidence is provided here that the greater robustness of sp-FLASE may outweigh the benefits of the minor SNR gain of b-FLASE for the target application of TB imaging in the distal extremities, sites of exclusively fatty marrow. Results are supported by a theoretical Bloch equation analysis and the pulse sequence dependence of the effective T(2) of triglyceride protons. Last, sp-FLASE images are shown to provide detailed and reproducible visual depiction of trabecular networks in three dimensions at both anisotropic (137 x 137 x 410 microm(3)) and isotropic (160 x 160 x 160 microm(3)) resolutions in the human distal tibia in vivo.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica
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Tibia
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Algoritmos
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Interpretación de Imagen Asistida por Computador
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Aumento de la Imagen
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Imagen Eco-Planar
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Imagenología Tridimensional
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Magn Reson Med
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos