Diffusion-weighted imaging of primary brain lymphomas: Effect of ADC value and signal intensity of T2-weighted imaging

The purpose of this study was to determine whether apparent diffusion coefficient (ADC) value and T2 signal intensity (SI) in primary brain lymphomas affect their SI on diffusion-weighted images (DWI). On DWI of 16 brain lesions of 16 patients, 9 (56.2%) were hyperintense (grade-3), 4 (25%) partially hyperintense (grade-2) and 3 (18.8%) isointense (grade-1). The mean ADC value of grade-3 lesions was significantly lower than of grade-1 lesions (p = 0.028). The grade-1 lesions had ADC values of more than 0.8 and contrast-to-noise ratios of less than 18 on T2-weighted images. Their ADC value and T2 signal intensity affect their SI on DWI.