Application of fusion imaging in intraoperative instant curative effect evaluation of thermal ablation for primary liver cancer

Abstract

Objective To evaluate the application value of fusion imaging in intraoperative instant curative effect evaluation of thermal ablation for primary liver cancer (liver cancer). Methods Forty-six patients with liver cancer (71 lesions in total) undergoing ultrasound-guided thermal ablation in the Third Affiliated Hospital of Sun Yat-sen University between December 2014 and March 2015 were recruited in this prospective study. Forty-two patients were males and 4 were females, aged between 36 and 82 years with a median age of 54 years. The informed consents of all patients were obtained and the local ethical committee approval was received. After thermal ablation, clinical efficacy was preferentially assessed by contrast-enhanced ultrasound (CEUS)-computed tomography (CT)/magnetic resonance imaging (MRI) fusion imaging technique for all liver cancer lesions. If the fusion imaging was not successfully performed, simple CEUS was utilized for evaluation. According to the evaluation methods, the patients were divided into the fusion imaging group and CEUS group. The lesion size, supplementary and complete ablation rates in two groups were observed. The lesion diameter between two groups was compared using Z test and the ratio was compared using Chi-square test or Fisher's exact probability test. Results Fusion imaging was utilized for instant curative effect evaluation in 25 patients with 31 lesions, and simple CEUS was used for evaluation in 26 cases with 40 lesions. In the fusion imaging group, 58% (18/31) of the lesions were ≥20 mm in diameter, significantly higher compared with 30% (12/40) in the CEUS group (χ2=5.638, P<0.05). The supplementary ablation rate in the fusion imaging group was 52% (16/31), significantly higher than 22%(9/40) in the CEUS group (χ2=6.489, P<0.05). The complete ablation rate was 100% (31/31) in the fusion imaging group and 95%(38/40) in the CEUS group , and no significant difference was observed (P=0.501). Conclusions Both fusion imaging and simple CEUS are important methods for intraoperative instant curative effect evaluation. Fusion imaging has higher accuracy for the relatively large lesions and help to enhance the complete ablation rate. Key words: Ultrasonography; Carcinoma, hepatocellular; Ablation techniques; Comparative effectiveness research