Objective: To assess whether ADC maps obtained from high b value DWI were more valuable in preoperatively evaluating the grade, Ki-67 index and outcome of gliomas.
Methods: Sixty-three patients with gliomas, who underwent preoperative multi b value DWI at 3 T, were enrolled. The ADC1000, ADC2000 and ADC3000 maps were generated. Receiver operating characteristic analyses were conducted to determine the area under the curve (AUC) in differentiating high-grade gliomas (HGG) from low-grade gliomas (LGG). Pearson correlation coefficients (R value) were calculated to investigate the correlation between parameters with the Ki-67 proliferation index. Survival analysis was conducted by using Cox regression.
Results: The AUC of the mean ADC1000 value (0.820) was lower than that of the mean ADC2000 value (0.847) and mean ADC3000 value (0.875) in differentiating HGG from LGG. The R value of the mean ADC1000 value (-0.499) was less negative than that of the mean ADC2000 value (-0.530) and mean ADC3000 value (-0.567). The mean ADC3000 value was an independent prognosis factor for gliomas (p = 0.008), while the mean ADC1000 and ADC2000 values were not.
Conclusion: ADC maps obtained from high b value DWI might be a better imaging biomarker in the preoperative evaluation of gliomas.
Key points: • ADC 3000 maps could improve the differentiation between HGG and LGG. • The mean ADC 3000 value had a closer correlation with the Ki-67 index. • The mean ADC 3000 value was an independent prognosis factor for gliomas.
Keywords: Diffusion magnetic resonance imaging; Glioma; Ki-67 antigen; Neoplasm grading; Prognosis.