Comparison of ADC values in three different diffusion weighted MR imaging acquisitions of the liver
10.3969/j.issn.1002-1671.2015.03.029
- VernacularTitle:肝脏扩散加权成像3种呼吸方式下ADC值的比较
- Author:
Zhuo SHI
;
Feng YE
- Publication Type:Journal Article
- Keywords:
apparent diffusion coefficient;
liver;
respiratory-trigger;
breath-hold;
free-breathing
- From:
Journal of Practical Radiology
2015;(3):458-462
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare and determine the reproducibility of apparent diffusion coefficient (ADC)values of the normal liver parenchyma in respiratory-triggered,breath-hold,and free-breathing diffusion weighted magnetic resonance imaging (DWI). Methods 11 volunteers did three times of breath-hold (excitation number is 1,at the end of the expiration,thickness/gapping=5 mm/1 mm), respiratory-triggered (excitation number is 2,at the end of the expiration,thickness/gapping=5 mm/1 mm),free-breathing (excitation number is 4,thickness/gapping=5 mm/1 mm)and for a total of nine axial liver DWI,the gradient factor was 800 s/mm2 .Then they were all coronally reconstructed (thickness/gapping=8 mm/1 mm).The nonparametric test was used to compare all axial and coronally reconstructed liver ADC values;and the Bland-Altman method was used to evaluate the ADC values’repeatability in coronally reconstructed images.Results The breath-hold DWI’s mean ADC value was (1.09±0.07)×10-3 mm2/s significantly lower than the respiratory-triggered DWI(1.16± 0.09)×10-3 mm2/s and the free-breathing DWI(1.19±0.10)×10-3 mm2/s(P<0.005),the axial and coronal images’results were similar.The ADC values’average difference and scope of consistency of coronal image were (-0.09 to -0.01±0.09 to 0.48)for breath-hold DWI,(-0.04 to 0.01±0.11 to 0.17)for respiratory-triggered DWI,(-0.07 to -0.02±0.11 to 0.18)for free-breathing DWI,respectively.Conclusion The breath-hold DWI’s ADC value of normal liver parenchyma is lower than the respiratory-triggered and free-breathing DWI,and showed more poorer repeatability.It is suggested that the measurement of ADC values of the liver parenchyma should be done within the respiratory-triggered or free-breathing DWI.
