A variable flip angle golden-angle-ordered 3D stack-of-radial MRI technique for simultaneous proton resonant frequency shift and T1 -based thermometry.
Magn Reson Med
; 82(6): 2062-2076, 2019 12.
Article
en En
| MEDLINE
| ID: mdl-31257639
ABSTRACT
PURPOSE:
To develop and evaluate a variable-flip-angle golden-angle-ordered 3D stack-of-radial MRI technique for simultaneous proton resonance frequency shift (PRF) and T1 -based thermometry in aqueous and adipose tissues, respectively.METHODS:
The proposed technique acquires multiecho radial k-space data in segments with alternating flip angles to measure 3D temperature maps dynamically on the basis of PRF and T1 . A sliding-window k-space weighted image contrast filter is used to increase temporal resolution. PRF is measured in aqueous tissues and T1 in adipose tissues using fat/water masks. The accuracy for T1 quantification was evaluated in a reference T1 /T2 phantom. In vivo nonheating experiments were conducted in healthy subjects to evaluate the stability of PRF and T1 in the brain, prostate, and breast. The proposed technique was used to monitor high-intensity focused ultrasound (HIFU) ablation in ex vivo porcine fat/muscle tissues and compared to temperature probe readings.RESULTS:
The proposed technique achieved 3D coverage with 1.1-mm to 1.3-mm in-plane resolution and 2-s to 5-s temporal resolution. During 20 to 30 min of nonheating in vivo scans, the temporal coefficient of variation for T1 was <5% in the brain, prostate, and breast fatty tissues, while the standard deviation of relative PRF temperature change was within 3°C in aqueous tissues. During ex vivo HIFU ablation, the temperatures measured by PRF and T1 were consistent with temperature probe readings, with an absolute mean difference within 2°C.CONCLUSION:
The proposed technique achieves simultaneous PRF and T1 -based dynamic 3D MR temperature mapping in aqueous and adipose tissues. It may be used to improve MRI-guided thermal procedures.Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Procesamiento de Imagen Asistido por Computador
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Imagen por Resonancia Magnética
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Tejido Adiposo
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Imagenología Tridimensional
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Ultrasonido Enfocado de Alta Intensidad de Ablación
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Termometría
Límite:
Animals
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Female
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Humans
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Male
Idioma:
En
Año:
2019
Tipo del documento:
Article