ABSTRACT

To detect apparent diffusion coefficient (ADC) values in normal abdominal organs using non-breath-hold high b-value diffusion-weighted magnetic resonance imaging (DW-MRI) with a parallel imaging technique.

A total of 50 patients with normal abdominal MRI findings were retrospectively enrolled. DW-MRI was performed with b-factors of 0, 500, and 1000 s/mm2. Mean ADC measurements were calculated.

There were statistically significant differences (P < 0.001) between the ADC values of four liver segments (left lobe lateral segment: 1.77 ± 0.21 x10-3 mm2/s, left lobe medial segment: 1.59 ± 0.21 x 10-3 mm2/s, right lobe anterior segment: 1.46 ± 0.18 x 10-3 mm2/ s, right lobe posterior segment: 1.34 ± 0.20 x 10-3 mm2/s). The ADC value for the left lobe lateral segment was significantly higher than the values for the other segments. The calculated ADC values for cortex and medulla of kidney were 2.08 ± 0.22 x 10-3 mm2/ s, 1.94 ± 0.18 x 10-3 mm2/s, respectively; (P < 0.001), for pancreas tail 1.59 ± 0.38 x 10-3 mm2/s, for pancreas body 1.68 ± 0.26 x 10-3 mm2/s, pancreas head 1.65 ± 0.29 x 10-3 mm2/s, stomach wall 1.84 ± 0.22 x 10-3 mm2/s, and spleen 1.28 ± 0.38 x 10-3 mm2/s.

Knowledge of ADC values for normal abdominal organs will be required during quantitative evaluation of DW-MR images in diseases in accordance with the technique used. We believe that further studies investigating the effect of diseases on normal ADC values are necessary and would be helpful in quantitative DWI.

Keywords: diffusion magnetic resonance imaging• abdomen