Diffusion-weighted magnetic resonance imaging using different b-value combinations for the evaluation of treatment results after volumetric MR-guided high-intensity focused ultrasound ablation of uterine fibroids.
Eur Radiol
; 24(9): 2118-27, 2014 Sep.
Article
em En
| MEDLINE
| ID: mdl-24962829
ABSTRACT
OBJECTIVES:
To assess the value of diffusion-weighted magnetic resonance imaging (DWI) and apparent diffusion coefficient (ADC) mapping using different b-value combinations for treatment evaluation after magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) of uterine fibroids.METHODS:
Fifty-six patients with 67 uterine fibroids were treated with volumetric MR-HIFU. Pre-treatment and post-treatment images were obtained using contrast-enhanced T1-weighted MRI (CE-T1WI) and DWI using b = 0, 200, 400, 600, 800 s/mm(2). ADC maps were generated using subsets of b-values to investigate the effects of tissue ablation on water diffusion and perfusion in fibroids treated with MR-HIFU. Four combinations of b-values were used (1) all b-values; (2) b = 0, 200 s/mm(2); (3) b = 400, 600, 800 s/mm(2); and (4) b = 0, 800 s/mm(2).RESULTS:
Using the lowest b-values (0 and 200 s/mm(2)), the mean ADC value in the ablated tissue reduced significantly (p < 0.001) compared with baseline. Calculating the ADC value with the highest b-values (400, 600, 800 s/mm(2)), the ADC increased significantly (p < 0.001) post-treatment. ADC maps calculated with the lowest b-values resulted in the best visual agreement of non-perfused fibroid tissue detected on CE images. Other b-value combinations and normal myometrium showed no difference in ADC after MR-HIFU treatment.CONCLUSIONS:
A decrease in contrast agent uptake within the ablated region on CE-T1WI was correlated to a significantly decreased ADC when b = 0 and 200 s/mm(2) were used. KEY POINTS DWI could be useful for treatment evaluation after MR-HIFU of uterine fibroids. The ADC in fibroid tissue is influenced by the choice of b- values. Low b-values seem the best choice to emphasise perfusion effects after MR-HIFU.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Uterinas
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Interpretação de Imagem Assistida por Computador
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Cirurgia Assistida por Computador
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Imagem de Difusão por Ressonância Magnética
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Ablação por Ultrassom Focalizado de Alta Intensidade
/
Leiomioma
Tipo de estudo:
Prognostic_studies
Limite:
Adult
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Female
/
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article