The role of late-phase pulse inversion harmonic imaging in the detection of occult hepatic metastases

Percutaneous radiofrequency ablation guided by contrast-enhanced ultrasound in treatment of metastatic hepatocellular carcinoma after liver transplantation

This study evaluated the advantages and applications of contrast-enhanced ultrasound (CEUS)-supported percutaneous radiofrequency ablation (RFA) in the treatment of metastatic hepatocellular carcinoma after liver transplantation, based on clinical details. CEUS-supported percutaneous RFA was adopted to treat 12 patients with hepatic metastatic carcinomas after liver transplantation. The diameters of the metastatic carcinomas varied from 1 cm to 5 cm, and the foci were discovered after 3 months to 12 months. Each focus was diagnosed and localised by CEUS for RFA once or twice. Curative effects were evaluated by CEUS or contrast-enhanced CT after the treatment. The re-examination results at 2 weeks post-treatment showed that the foci of 11 patients were ablated completely, whereas one patient with the largest focus required retreatment by RFA because of a partial residue. No local recurrence was found one month later in the re-examination. CEUS-supported percutaneous RFA in the treatment of hepatic metastatic carcinoma after liver transplantation has the advantages of accurate localisation, good efficacy, easy operation, and minimal invasion without any complications. Therefore, it can be recommended as the preferred therapy for hepatic metastatic carcinoma after liver transplantation.

Role of sonography for implantation and sequential evaluation of a VX2 rabbit liver tumor model

OBJECTIVE

We investigated the role of sonography in the implantation process of a VX2 rabbit liver tumor model and sequential evaluation.

METHODS

Fifty rabbits were divided into 2 groups. Animals in group I underwent surgical implantation, whereas those in group II received percutaneous sonographically guided implantation. At 7, 14, 21, and 28 days after implantation, respectively, 5 rabbits in each group were examined with conventional, color Doppler (CD), contrast-enhanced (CE) pulse inversion harmonic (PIH), and CE CD sonography. Pathologic examination was performed with hematoxylin-eosin, nicotinamide adenine dinucleotide phosphate-diaphorase, and succinic dehydrogenase stains.

RESULTS

Twenty-one rabbits with tumors survived in group I, and 22 with tumors survived in group II. The mean duration of implantation +/- SD in group II was 16.9 +/- 3.4 minutes, whereas that in group I was 21.5 +/- 4.1 minutes (P < .05). The tumor volume measured by conventional sonography increased from 0.28 +/- 0.14 cm(3) at 7 days to 16.49 +/- 5.50 cm(3) at 28 days in group I and from 0.31 +/- 0.19 to 19.79 +/- 4.70 cm(3) in group II, whereas no significant difference existed between the groups. On CD, CE PIH, and CE CD sonography, most tumors were hypervascular before 14 days and after 14 days had peripheral vessels and central hypovascular areas, which were shown as necrotic areas by pathologic examination.

CONCLUSIONS

Sonographically guided implantation achieved a good success rate with convenient inoculation performance. Conventional gray scale, CD, CE PIH, and CE CD sonography were useful in sequential evaluation of tumor growth and characteristic vascularity.

Radiofrequency ablation of hepatocellular carcinoma: value of virtual CT sonography with magnetic navigation

OBJECTIVE

Virtual CT sonography with magnetic navigation yields cross-sectional images of CT volume data that correspond to the angle of the transducer in the magnetic field in real time. The purpose of this study was to evaluate the efficiency and feasibility of virtual CT sonography for radiofrequency ablation of hypervascular hepatocellular carcinoma poorly defined on B-mode sonography.

MATERIALS AND METHODS

One hundred one patients enrolled in the study were separated into two groups. Fifty-one patients with 65 hepatocellular carcinomas underwent prospective virtual CT sonography as guidance for radiofrequency ablation. Fifty patients with 63 hepatocellular carcinomas managed with B-mode sonographic guidance were retrospectively selected under the same conditions as the virtual CT sonography group to act as a historical control group.

RESULTS

In the virtual CT sonography group, technically successful ablation was achieved in a single session in 92% (47/51) of the patients and in two sessions in 8% (4/51). In the B-mode sonography group, technical success was achieved in a single session in 72% (36/50) of the patients, in two sessions in 24% (12/50), and in three sessions in 4% (2/50). Treatment analysis showed that the technical success rate after a single treatment session was significantly (p = 0.017) higher for the virtual CT sonography group. The number of treatment sessions was significantly (p = 0.021) lower for the virtual CT sonography group (mean, 1.1 +/- 0.1 vs 1.3 +/- 0.3 sessions).

CONCLUSION

Virtual CT sonographically assisted radiofrequency ablation is an efficient treatment of patients with hepatocellular carcinoma that is poorly defined on B-mode sonography.