Amide proton transfer imaging in grading tumors of the neuroepithelial tissue

Abstract

Objective To investigate the role of the amide proton transfer (APT) MR sequence in grading tumors of the neuroepithelial tissue,and its application in identifying the different components of the tumors.Methods 33 patients (18 male,15 female,age was from 18 to 71 with mean age of 46 years) were investigated and confirmed to be tumors of neuroepithelial tissue (glioma) by postoperative pathology,in whom 3T MRI with T2-weighted,FLAIR,pre-and post-contrast T1-weighted and APT sequences were performed.For each patient,APT signal intensities of each regions of interest (ROI) was defined and used for grading.Comparisons of APT signal intensities of high grade were done among tumor core,peritumoral edema and the contralateral normal-appearing white matter (CNAWM) and the APT signal intensities of tumor core were also compared between high and low grade glioma.Results 33 patients included 10 grade Ⅱ tumors,11 grade Ⅲ tumors,and 12 grade Ⅳ tumors.The average APT signal intensities were significantly higher in the tumor cores both in high and low grade than the peritumoral edema (P ＜ 0.05)and the contralateral normal-appearing white matter (P ＜ 0.01).Moreover,the APT signal intensities of the tumor cores of high-grade brain tumors were significantly higher than those of low-grade (P ＜ 0.01).Conclusions Amide proton transfer contrast can differentiate the tumor core from peritumoral edema,and combined with routine MRI is of clinical application value in grading of glioma. Key words: Magnetic resonance imaging; Amide proton transfer; Neoplasms, neuroepithelial; Pathology