Usefulness of US-CT 3D dual imaging for the planning and monitoring of hepatocellular carcinoma treatment using HIFU.

Purpose: We evaluated the safety and usefulness of high-intensity focused ultrasound (HIFU) assisted by ultrasound-computed tomography three-dimensional (US-CT 3D) dual imaging for the treatment of hepatocellular carcinoma (HCC).

Materials And Methods: HIFU ablation was performed in 13 patients with small HCC (≤3 lesions, ≤3 cm in diameter). The HIFU system (Chongqing Haifu Tech) was used under ultrasound guidance. By transferring the sagittal or axial plane of the 3D US and the CT volume data into the ZioM900, multiplanar reconstruction images were displayed in a manner resembling conventional monitor US to assist the HIFU treatment.

Results: Overall, 69% (9/13) of the patients in whom good visualization using B-mode sonography could not be obtained because of the influence of multi-reflections, rib shadows, and unclear tumor margins were successfully treated under the guidance of US-CT 3D dual imaging. In 5 of the 13 patients, multi-reflections were responsible for the poor visualization. In 2 cases, the tumor was poorly visualized because of a rib shadow. In one case, the margin of the tumor was too unclear to be detected using ultrasography. The 3D US images obtained as part of the US-CT 3D dual imaging had a high resolution and were useful for examining the area of HCC invasion and for determining the extent of the ablation area. The CT images, which are not influenced by bone shadows or multi-reflections, were useful for detecting the tumors and for visualizing the presence of the intestines in the sonication zone. HIFU treatments were successfully performed in all the patients with the assistance of US-CT 3D dual imaging.

Conclusion: US-CT 3D dual imaging is useful for HIFU treatment for HCC, compensating for the occasionally poor visualization provided by US monitor.