The application study of multi-b value diffusion weighted imaging in preoperative histological grading of supratentorial glioma
10.3969/j.issn.1002-1671.2016.02.001
- VernacularTitle:多b值DWI对术前幕上胶质瘤分级的应用研究
- Author:
Xinguan YANG
;
Yufang HU
;
Guangjun LIU
;
Qinghua ZHANG
;
Weijia QIU
- Publication Type:Journal Article
- Keywords:
glioma;
magnetic resonance imaging
- From:
Journal of Practical Radiology
2016;(2):169-173
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the optimal b value of diffusion-weighted imaging (DWI)in predicting the grade of cerebral gliomas.Methods 38 patients with pathologically-proved brain gliomas (24 high-grade gliomas and 14 low-grade ones)were studied retrospectively.All patients received conventional MRI and DWI examination with three different b values (1 000 s/mm2 ,2 000 s/mm2 and 3 000 s /mm2 ).The signal features of the tumor on DWI with three different b values were evaluated and compared.The minimum ADC values of the tumors were calculated and compared between each other.Through drawing the ROC curve of different b values, the best diagnostic threshold was found.The sensitivity and specificity in predicting the grade of brain gliomas were assessed using Chi-square test.Results On DWI with b value of 3 000 s/mm2 ,91.6% (22/24)of high-grade tumors showed hyper-intensity, while 85.7%(12/14)of low-grade tumors presented hypo-intensity signals.Regarding hyper-intensity signals as diagnostic criterion for high-grade tumors,the sensitivity and specificity were 91.6% and 100% respectively.When the b value was similar,the minimum ADC value of high-grade glioma was significantly lower than that of low-grade glioma,and statistically significant differences in differentiating high-grade glioma from low-grade glioma existed among three b values (P <0.05).When the ADC 3 000 value<0.74×10 -3 mm2/s was regarded as a standard for the identification of high-grade and low-grade glioma,the sensitivity and specificity were 100% and 87.3%respectively.Conclusion DWI with high b value is more useful than standard moderate b value in preoperative grading the gliomas.When DWI with b value of 3 000 s/mm2 is used,the minimum ADC value will provide quantitative indicators in preoperatively precisely predicting grading glioma.
