Abstract

Introduction: To evaluate the effect of increasing portal flow due to food intake on the parameters of Intravoxel Incoherent Motion (IVIM) and T2^* relaxation time in healthy liver.

Materials and methods: The subjects consisted of 15 healthy volunteers. We used a 1.5 T MRI system. All subjects received MRI three times as follows: after overnight fasting but before food intake, at 30 min, and at 4 h after food intake. MRI was repeated at a greater than 1 week interval. All subjects had 800 kcal of Calorie Mate. The echoplanar diffusion-weighted imaging was performed under free breathing and 10 b-values (0, 10, 20, 30, 50, 80, 100, 200, 400, 800 s/mm²) were obtained. T2^*-weighted imaging with multi-echo gradient-echo sequence was performed with Siemens MapIt software under breath-holding. The portal flow measurement was performed with phase contrast sequence. The parameters of IVIM including ADC, DC, D^*, and PF were calculated and T2^* relaxation time was obtained using MapIt.

Results: The portal blood flow increased significantly 30 min after food intake (P<0.0001). The ADC, DC, D^*, PF and T2^* values after overnight fasting, at 30 min, and at 4 h after food intake showed no significant differences after food intake.

Conclusion: Increasing portal venous flow after food intake does not affect IVIM parameters and T2^* of liver parenchyma in healthy volunteers.

Keywords: Liver; Intravoxel incoherent motion; Food intake; Diffusion weighted imaging