[Usefulness of short inversion time inversion recovery-low B diffusion weighted imaging after pouring in gadolinium- ethoxybenzyl-diethylene-triaminepentaacetic acid].

Diffusion weighted imaging (DWI) using a low b value for examination of the body is not common, so we examined its usefulness. Phantom experiments were performed in which I changed the length of the echo time (TE), with and without short inversion time inversion recovery (STIR). The signal intensity of each phantom was reduced by using a longer TE or by combination with STIR, but contrast was improved. We noted a similar pattern in clinical cases, and concluded that the results of the phantom study and clinical cases indicated the potential usefulness of TE with moderate STIR. Low-b DWI using appropriate imaging parameters gave better results than high-b DWI followed by visual assessment. The T1 value of normal liver cells is shortened by incorporating gadolinium-ethoxybenzyl-diethylene-triaminepentaacetic acid (Gd-EOB-DTPA). Normal liver cells are close to the null point in STIR-low-b DWI under these conditions. The signal-to-noise ratio (SNR) of normal liver cells thus decreases, unlike that for tumors containing no normal liver cells, giving improved contrast. At high SNRs, the use of low-b DWI provides several advantages: the anatomical location structure is easy to identify, and there is less left lateral division of liver signal degradation. We thus conclude STIR-low-b DWI after injection of Gd-EOB-DTPA to be a useful technique.