Low-dose hepatic computed tomography perfusion imaging and its preliminary study

Computed tomography perfusion imaging (CTPI) is a rapid and non-invasive functional imaging method that reflects hemodynamic changes of liver diseases. However, its large radiation dosage limits its clinical application. We aimed to evaluate the feasibility of low-dose CTPI in normal liver and its preliminary application in hepatocellular carcinoma (HCC).

CTPI was performed in 34 healthy volunteers randomly divided into three groups with different applications of tube current, including a conventional dose group, a median-dose group and a low-dose group. The perfusion parameters of each group were compared and a low-dose CTPI was performed in 13 patients with HCC.

Relatively satisfying images and perfusion parameters of liver CTPI were acquired with the different tube currents. There were no significant differences between the parameters of the three groups (P>0.05). The effective dosage of conventional, median and low-dose liver CTPI were 19.62 mSv, 12.61 mSv, and 7.01 mSv, respectively. The radiation dosage of low-dose liver CTPI was reduced to 64.27% compared with that of the conventional group. The hepatic blood flow, hepatic blood volume and hepatic perfusion index of HCC were higher than background liver parenchyma and normal liver.

Low-dose liver CTPI obtained similar perfusion parameters result to that of the conventional-dose, whereas the radiation dosage was reduced by 2/3. Low-dose liver CTPI can reflect the hemodynamic change of HCC. Low-dose liver CTPI has potential clinical value for diagnosis and differential diagnosis of liver diseases.