Diffusional kurtosis imaging value for assessment of liver cancer and tumoral cell invasion of peritumoral zone

Abstract

Objective Study the apply of diffusional kurtosis imaging(DKI) value to assess liver cancer and tumoral cell invasion of peritumoral liver zone. Methods This research belonging to prospective study which included 24 patients with liver cancer and confirmed by clinical history and imaging features (liver cancer group) , 10 healthy volunteers as control group. The liver cancer group underwent MRI plain and contrast enhanced scan, and DKI examination, while control group underwent MRI plain scan and DKI scan. The signal features of liver parenchyma and liver cancer lesion could be observed from the routine MRI and DKI. Fractional anisotropy (FA), mean diffusion (MD), axial diffusivity (Da), radial diffusivity (Dr), fractional anisotropy kurtosis (Fak), mean kurtosis (MK), kurtosis anisotropy (Ka) and radial kurtosis (Kr) value of four groups, the distant liver parenchyma(far away from the tumor>2 cm), peritumoral liver parenchyma(the distance ≤2 cm around the tumor) and liver cancer were recorded. The differences of DKI parameters were evaluated using one-way analysis of variance (ANOVA). Results The signal of liver cancer in MR plain scan showed mild long T1 and mild long T2 signal, fast in and fast out enhanced feature of the neoplasms could be observed from the enhanced MRI and signal of liver cancer would not lower in DKI with b value up to top. The difference of DKI parameters including FA, MD, Da, Dr and Ka value had statistical significance in these four groups excepted for MK and Kr value. MD, Da and Dr value of normal parenchyma were higher than that of peritumoral parenchyma and liver cancer,while the Ka value was reverse. The differences of MD, Da, Dr and Ka value only had no statistical significance between the distant liver parenchyma and peritumoral liver parenchyma(P>0.05),and the differences of them had statistical significance among the rest group(P<0.05). Conclusion The DKI quantitative parameters can reflect the differences of different tissue, meaning that they can provide molecular imaging information for evaluating liver cancer and peritumoral zone. Key words: Liver neoplasms; Magnetic resonance imaging; Comparative study