Diagnosis of peritoneal metastases with abdominal malignancies: Role of ADC measurement on diffusion weighted MRI

Objective: The purpose of our study was to evaluate the utility of the apparent diffusion coefficient (ADC) value measurement in the diagnosis of peritoneal metastases on diffusion weighted magnetic resonance imaging. Materials and Methods: Diffusion weighted imaging with conven- tional magnetic resonance imaging sequences was performed on twenty consecutive oncology patients (group I) with peritoneal me- tastases. The ADC values of the metastases, the peritoneal fat around the metastases (group I) and the peritoneal fat in patients with no malignancy (group II) at b(0-100), b(0-600), and (b 0-1000) s/mm²gra- dients were measured and compared. Results: The apparent diffusion coefficient values of three gradients in peritoneal metastases (2.27±0.4; 1.67±0.7 and 1.09±0.4×10^-3 mm²/s at b 100, 600 and 1000 gradients, respectively) were significantly lower than the ADC values of the peritoneal fat around metastases (3.07±0.4; 2.07±0.4; 1.33±0.3×10^-3 mm²/s at b 100, 600 and 1000 gra- dients, respectively) (p<0.05). There was no significant difference be- tween the ADC values of peritoneal fat in the patients of group I and group II at the 3 diffusion gradients (p>0.05). Conclusion: The measurement of ADC values may be used as a com- plementary diagnostic method in differentiating peritoneal metasta- ses from peritoneal fat on Diffusion Weighted MRI (DWMRI DWMRI).