Quantitative evaluation of early stage blood flow change status after radiofrequency ablation based on multi-slice spiral CT whole-liver perfusion imaging on small hepatocellular carcinoma

Abstract

Objective: To investigate the blood flow change status in early stage tumor-related areas of hepatocellular carcinoma and its clinical significance after radiofrequency ablation using multi-slice spiral CT whole-liver perfusion imaging technology. Methods: 21 cases of primary liver cancer that underwent CT-guided radiofrequency ablation were included. CT perfusion scans were divided into four groups according to the time points of CT scans (before surgery, immediately after surgery and 1 and 3 month after surgery), and then blood perfusion parameters of the corresponding areas of the tumor were measured. Statistical analysis was performed using two independent samples of non-parametric Wilcoxon rank-sum test. The differences of blood perfusion parameters between tumor or ablation lesion and background liver parenchyma, paratumor tissue or inflammatory response zone were compared before, immediately and 1 and 3 months after surgery, respectively. Results: (1) The hepatic arterial perfusion (HAP) and hepatic arterial perfusion index (HPI) of cancerous liver tumors and background liver parenchyma was significantly increased (P < 0.01). The total liver perfusion (TLP) was higher than the background liver parenchyma (P = 0.01 < 0.05). The time to peak (TTP) was significantly lower than background liver parenchyma (P < 0.01); (2) The perfusion parameters of HAP, PVP and TLP were lower than the background liver parenchyma in the complete ablation lesions immediately after radiofrequency ablation and 1 and 3 months after surgery, and the difference was statistically significant (P < 0.05); (3) The inflammatory response zone of ablation lesions of HAP, HPI, and TLP were gradually decreased with the extended postoperative time and TTP was gradually increased, while PVP did not change significantly; (4) HAP, HPI, and TTP were compared between the tumor and the tumor inflammatory response zone immediately after surgery, and 1 and 3 months after surgery, and the difference was statistically significant (P < 0.01). However, there was no statistically significant difference between PVP and TLP (P > 0.05). Conclusion: CT whole-liver perfusion imaging can precisely evaluate the early stage blood flow change status in peritumor and tumors before and after radiofrequency ablation and then objectively evaluate tumor's blood supply and therapeutic effect on hepatocellular carcinoma.