Comparison of ADC Values Obtained in 2D and 3D for Differentiation between Healthy Brain Tissues, Glioblastoma and Meningioma

Abstract

Diffusion-Weighted Imaging (DWI) has been used to study various neurological diseases, such as stroke, dementia and brain tumors. The DWI contrast is based on random microscopic motion of water protons, which can be altered by pathological process. From DWI is obtained the ADC (Apparent Diffusion Coefficient) map, which is a representation of the magnitude of water diffusion of a given ROI (Region of Interest). The aim of this study was to compare ADC mean values calculated in 2D and 3D for differentiation between healthy brain tissues, glioblastoma and meningioma. For patients, the 2D mean ADC values were calculated in a ROI covering the tumor, in the transversal slice more representative of lesion. Also, the 3D mean ADC values were obtained using a 3D ROI over the three slices more representatives of lesions. For glioblastoma, the 2D and 3D mean ADC values obtained were ((2.6 ± 0.96) × 10^− 4 mm²/s) and ((2.83 ± 0.8) × 10^− 4 mm²/s), respectively. For meningioma, these values were (4.88 ± 1.36) × 10^− 4 mm²/s) and (5.37 ± 0.76) × 10^− 4 mm²/s), respectively. For controls, mean 2D ADC values ((8.99 ± 1.09) × 10^− 4 mm²/s) were obtained in a ROI covering white and gray matter of brain, in a unique slice of volume. For these subjects, the 3D mean ADC values ((9.27 ± 0.61) × 10^− 4 mm²/s) were calculated for 10 different ROIs located where the tumors were present in the patients. In 2D or 3D, the analysis of variance of ADC values obtained for the group of patients and controls resulted in p-value < 0.05, pointing to distinction between these three groups. Bonferroni test did not confirm distinction between meningioma and healthy tissue for 3D ADC values.