The effect of susceptibility of Gadolinium contrast media on diffusion weighted image and the apparent diffusion coefficient

Purpose: The development of parallel MRI has resulted in the frequent use of diffusion-weighted imaging (DWI) in clinical medicine, and it usually involves the use of contrast medium. However, the gadolinium (Gd) contrast medium may have some effect on DWI and the apparent diffusion coefficient (ADC). The present study was performed to determine whether the magnetic susceptibility of contrast medium alters the DWI signal and the value of ADC in some imaging techniques. Materials and Methods: Non-fat suppression DWI, STIR combination and CHESS combination DWI were performed to examine 10 phantoms with Gd-DTPA dissolved at concentrations from 0.0005 to 0.1 mmol in physiological saline as contrast medium. The average pixel value and ADC of each method were determined. Results: ADC showed no differences between before and after treatment with contrast medium for all imaging techniques with Gd considered to be distributed over the whole tumour. The signal intensity did not change on non-fat suppression or CHESS combination DWI but deteriorated on STIR. Therefore, ADC was not influenced by the magnetic susceptibility of contrast medium. In addition, it was suggested that the ability of tumour detection may be reduced if STIR is used as fat suppression.