PURPOSE

The purpose of this study is to identify the role of diffusionweighted magnetic resonance imaging (DW-MRI) in the classification of liver hydatid cysts (HCs) and their differentiation from simple cysts and liver abscesses.

MATERIALS AND METHODS

Twenty-two patients that were sent to our department with preliminary diagnoses of HCs or abscess were included in the study. Thirty lesions were evaluated. MRI included T1-weighted fast gradient echo, T2-weighted half-Fourier acquisition single-shot turbo spin echo, and DW single-shot echo planar pulse sequencing (b, 0, 50, and 1000 s/mm2). The apparent diffusion coefficient (ADC) values (mm2/s) of the HCs, abscesses, and simple cysts were calculated.

RESULTS

No statistically significant difference was found between the ADC values of type 1 and 3 (P > 0.05) HCs and of simple cysts and type 1 HCs (P > 0.05). The ADC values of abscesses were significantly lower than those of type 1 and type 3 HCs, and simple cysts. No statistically significant difference was found between the ADC values of abscesses and type 4 HCs (P > 0.05). Type 4 lesions exhibited significantly lower ADC values in comparison to type 1 and 3 HCs.

CONCLUSION

DW-MRI helps differentiate type 4 lesions from other cysts and can distinguish abscesses from hydatid cysts other than type 4 as well as from simple cysts. Type 1 HCs cannot be differentiated from simple cysts using ADC values alone, and type 4 lesions are indistinguishable from abscesses.

Keywords: liver, echinococcosis , magnetic resonance imaging , diffusion-weighted MRI