RÉSUMÉ
Objective To evaluate the feasibility and accuracy of virtual navigation contrast enhanced sonography in accurately location of small liver tumors which cannot be detected by conventional sonography during microwave ablation therapy. Methods Twenty-three patients with 28 small liver tumors,which could not be detected by conventional sonography but CT/MRI,underwent microwave ablation with virtual navigation contrast enhanced sonography from January 2015 to March 2017 at Nanfang Hospital. After fusion of images from both sonography and CT/MRI,small liver tumors were ablated under the real-time monitoring of navigated sonography. Virtual navigation contrast enhanced sonography was also utilized to evaluate the efficacy of ablation after the ablation.All patients underwent CT/MRI examination at one month post-ablation to evaluate the efficacy of ablation. Results Virtual navigation system successfully provided image fusion for all patients and all lesions(image fusion efficacy was 100%). All patients underwent virtual navigation contrast enhanced sonography monitored microwave ablation.Only one patient received extra ablation since a small proportion of residual tumor checked after the initial ablation. No severe complications occurred in the present study. One-month after ablation,all patients showed complete ablation by further CT/MRI examinations.Conclusion Virtual navigation sonography can precisely target small liver tumors which are undetected by conventional sonography.Evaluation of lesions and ablation efficacy can be performed with the help of virtual navigation contrast enhanced sonography during the ablation period,which have shown satisfactory clinical efficacy.