[Application of susceptibility weighted imaging in revealing intratumoral blood products and grading gliomas].
OBJECTIVE
Susceptibility weighted imaging (SWI) is a novel imaging method that utilizes the magnetic susceptibility differences between tissues. The purpose of our study was to evaluate the application of SWI for revealing inratumoral blood products and diagnosing high-grade gliomas.


METHODS
Conventional MR sequences and SWI were performed in 32 patients, 10 low-grade gliomas (1 grade I and 9 grade II) and 22 high-grade gliomas (8 grade III and 14 grade IV). The ability of SWI for detecting inratumral blood products was analyzed and compared with conventional MR sequences. Logistic regression and Receiver operating characteristic (ROC) curve analysis were used to evaluate the diagnostic value of SWI for high-grade gliomas.


RESULTS
SWI was sensitive for showing intrtumoral blood products (P=0.00) and depicted much more micro bleeds. No statistical difference was found in detection rate of blood products between low-grade and high-grade group. According to the result of logistic regression, the frequency of blood products and the diameter of maximum blood products were significant determinants of high-grade gliomas. The result of ROC analysis indicated that with an optimal cut-off point (0.67), the sensitivity, specificity, positive predictive value and negative predictive value for diagnosing high-grade gliomas with blood products detected by SWI were 81.8%, 80.0%, 90.0%, and 66.6%, respectively.


CONCLUSIONS
SWI can accurately detect blood products with superlative contrast. With a high-grade gliomas risk estimation model based on two variables, satisfied sensitivity, specificity, PPV and NPV were obtained. Thus, SWI could be a useful adjunct sequence in glioma grading.
Département de Radiologie, Deuxième Hôpital Affilié à la Faculté de Médecine de Chongqing, Chongqing, Chine. zhaojiannnong@gmail.com
W
W
Zhang
J
J
Zhao
D
D
Guo
W
W
Zhong
J
J
Shu
Y
Y
Luo
D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000175:diagnosis / Q000473:pathology; D001798:Blood Proteins / Q000032:analysis*; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D005909:Glioblastoma / Q000175:diagnosis / Q000473:pathology; D005910:Glioma / Q000175:diagnosis* / Q000473:pathology; D006470:Hemorrhage / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D055815:Young Adult
D001798:Blood Proteins