Intravoxel Incoherent Motion Diffusion-Weighted Imaging and 3D-ASL to Assess the Value of Ki-67 Labeling Index and Grade in Glioma

Abstract

Objective. To determine the proportion of intravoxel incoherent motion diffusion-weighted images (IVIM-DWI) and three-dimensional arterial circulation markers (3D-ASL) in Ki-67 labeling index (Ki-67 LI) and glioma grading. Methods. According to the classification of diseases of the central nervous system dealt with by WHO in 2007, patients with stage II glioma were classified as low (n=20) and patients with stages III-IV were divided into higher levels (n=22). Prior to surgery, brain MRI, IVIM-DWI, and 3D-ASL were performed in all patients, and the actual water molecular diffusion coefficient (D), microcirculation coefficient (D∗), blood flow fraction (f), and cerebral blood flow (CBF) were measured. A rank sum (Mann-Whitney U test) was used to compare the four upper and lower level Ki-67 LI measurements. Spearman's method is used to identify the relationship between 4 groups of quantification and Ki-67 LI. Reciprocal grafting (ROC) curves were used to measure the diagnosis of four groups of glioma grading defects. Results. There were significant differences in D, D∗, f, and CBF between the solid region of the tumor and the normal white matter contralateral to it (P<0.05). The significant differences of rD, rD∗, rf, and rCBF were shown between patients with low-grade glioma and high-grade glioma (P<0.05). Ki-67 LI was found to have negative correlation with rD (r=00.693, P<0.001) and rf (r=00.539, P<0.001), but similarly correlated with rCBF (r=0.665, P<0.001) in patients with glioma. Recipient efficacy for predicting advanced and secondary glioma from rD, rf, rD∗, rCBF, and Ki-67 LI raises AUCs of 0.819, 0.747, 0.719, 0.836, and 0.907, respectively. Conclusion. IVIM-DWI has good application value for preoperative grading of glioma.