Combined value of susceptibility-weighted and perfusion-weighted imaging in assessing WHO grade for brain astrocytomas

Purpose To assess the value of combining susceptibility-weighted imaging (SWI) and dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion-weighted MRI (PWI) in assessing World Health Organization (WHO) grade for brain astrocytoma. Materials and Methods A total of 94 patients with pathologically confirmed astrocytomas underwent SWI and DSC scans. The evaluation included intratumoral susceptibility signal intensity (ITSS) and relative cerebral blood volume (rCBV) max. The receiver operating characteristic curve (ROC) was used to assess the efficacy of combining two sequences in astrocytoma grading. Results ITSS within astrocytomas showed significant correlations with rCBV max (r = 0.72; P < 0.01) and with tumor grades (r = 0.92; P < 0.01), and there was also a significant correlation between rCBV and tumor grade (r = 0.77; P < 0.001). The area under the ROC, SWI, PWI, SWI, and PWI, in differentiation of the grades II and III astrocytomas were 0.995, 0.942, and 1.000, respectively; identifying grades III and IV were 0.773, 0.919, and 0.978, respectively; and identifying high and low-grade astrocytomas were 0.999, 0.992, 1.000, respectively. Conclusion ITSS was useful for assessing the WHO tumor grade in this cohort of patients with astrocytoma. The combination of SWI and PWI may improve the diagnostic accuracy of astrocytoma grading. J. Magn. Reson. Imaging 2014;39:1569–1574. © 2013 Wiley Periodicals, Inc.