Purpose: To evaluate the clinical safety and efficacy of percutaneous radiofrequency ablation (RFA) using multitined expandable electrodes under magnetic resonance imaging (MRI) guidance in the treatment of small hepatocellular carcinomas (HCCs) in the hepatic dome. Materials and methods: The data of 49 patients with 50 HCC lesions in the hepatic dome who underwent MRI-guided RFA from April 2010 to January 2018 were retrospectively analyzed. Planning, targeting, and controlling were performed under MR-guidance during the procedure. The complications after RFA were observed. Follow-up MRI was performed to evaluate the curative effect. The local progression-free survival, recurrence-free survival, and overall survival rates were calculated using the Kaplan-Meier survival curve. Results: The procedures were successfully accomplished in all patients without major complications. The mean follow-up time was 36.9 ± 25.8 months (range, 3–99 months). Technical success was 100% after one RFA session with MRI assessment after 1 month. Local tumor progression was observed in one patient (2%) with the lesion located in the hepatic dome at 4 months on a subsequent follow-up MRI. The progression-free survival time was 25.0 ± 22.7 months (median, 17.0 months). The 1-,3-, and 5-year local tumor progression-free survival rates were all 98.0%. The 1-,3-, and 5-year recurrence-free survival rates were 68.1%, 39.9%, and 28.5%, respectively, and the estimated overall survival rates were 93.7%, 76.3%, and 54.3%, respectively. Conclusion: Planning, targeting, and controlling of RFA were well supported by MRI with acceptable time. MRI-guided RFA for small HCCs in the hepatic dome is safe and effective with fewer RF sessions.

Purpose: To evaluate the feasibility and therapeutic efficacy of 1.5-T MRI-guided and monitored microwave ablation in patients with hepatic malignant tumors. Materials and Methods: This retrospective study was approved by the ethics committee of the First Affiliated Hospital of Fujian Medical University. Thirty-five patients (32 men, three women) with 48 lesions (maximum diameter < 3 cm) underwent microwave ablation under the guidance and monitoring of a 1.5-T MRI. The MRI-compatible microwave generator was appended with a magnetic shield case, and the cable was combined with a choke coil for shielding the Larmor processing frequency. The average age of the patients was 56.51 ± 11.36 years (31–77 years). Twenty-eight patients (37 lesions) displayed hepatocellular carcinoma and seven patients (11 lesions) had metastatic liver carcinoma. The mean maximum tumor diameter was 12.31 ± 4.72 mm (range 5.0–25.7 mm). Results: MRI scans were performed simultaneously without electromagnetic interference during ablation. The average maximum diameter of the hypointense zone of the last monitored T2WI sequence, hypointense zone of post-procedure T2WI sequence, and hyperintense zone of post-procedure T1WI were 28.82 ± 7.58 mm, 29.79 ± 7.91 mm, and 28.28 ± 8.37 mm, respectively, with no observed statistical difference (F = 0.434, p = .649). The technical success rate was 100%. The average follow-up duration was 11.43 ± 5.29 (4–33) months. The technique efficacy rate was 100%. Conclusion: MRI-guided and monitored microwave ablation of hepatic malignant tumors is feasible and potentially safe and effective.

To investigate the feasibility and efficacy of liver-specific magnetic resonance imaging (MRI) with gadolinium-containing contrast agent guidance for microwave ablation (MWA) of recurrent small hep...

Objectives: This study aimed to investigate the technical methods and safety of artificial pneumothorax and artificial hydrothorax in the treatment of lung cancer adjacent to vital organs by CT-guided microwave ablation.Subjects and Methods: Three of the six patients were men and three were women, with a mean age of 66.0 years (range 47–78 years). There patients had primary pulmonary adenocarcinoma, one had lung metastasis from liver cancer, one had lung metastasis from colon cancer, and one had lung metastasis from bladder cancer. There were four patients with a single lesion, one with two lesions, and one with three lesions. The nine lesions had a mean diameter of 1.1 cm (range 0.4–1.9). In three patients, the lung cancer was adjacent to the heart, and in the remaining three, it was close to the superior mediastinum. Six patients were diagnosed with lung cancers or lung metastases and received radical treatment with microwave ablation (MWA) assisted by artificial pneumothorax and artificial hydrothorax in our hospital. Postoperative complications were observed and recorded; follow-up was followed to evaluate the therapeutic effect.Results: The artificial pneumothorax and artificial hydrothorax were successfully created in all six patients. A suitable path for ablation needle insertion was also successfully established, and microwave ablation therapy was carried out. 2 patients developed pneumothorax after operation; no serious complications such as operation-related death, hemothorax, air embolism and infection occurred.Moreover, 4–6 weeks later, an enhanced CT re-examination revealed no local recurrence or metastasis, and the rate of complete ablation was 100%.Conclusions: Microwave ablation, assisted by artificial pneumothorax, artificial hydrothorax, is a safe and effective minimally invasive method for treating lung cancer adjacent to the vital organs, and optimizing the path of the ablation needle and broadening the indications of the ablation therapy

Purpose: This study aimed to evaluate the immediate efficacy of magnetic resonance (MR)-guided microwave ablation (MWA) in rabbit kidneys implanted with VX2 tumors. Materials and methods: MR-guided MWA was performed in eight VX2 tumor-bearing rabbits. MR images after ablation were obtained and analyzed. The differences between the tissue specimens and MR images obtained after ablation were compared. Results: On the three-dimensional volumetric interpolated breath-hold T1-weighted (3D-VIBE-T1WI) sequence, a low signal intensity indicated the primary tumor at the center of the ablation area, which was surrounded by a peripheral high-signal area. The signal for the primary tumor in the fast spin-turbo spin-echo T2-weighted (FS-TSE-T2WI) sequence was lower than before, and the ablation zone showed a low signal that completely covered the primary tumor. There was no significant difference in volume among the low-signal areas of the primary tumor on FS-TSE-T2WI before MWA, the central low-signal area on 3D-VIBE-T1WI after MWA, and the tumor coagulation necrosis area on the tissue specimens (p > 0.05). No significant difference was found in the volume of ablation zones among the tissue specimens, the high-signal area around the lesion on the 3D-VIBE-T1WI sequence, and the low-signal area covering the lesion on the FS-TSE-T2WI sequence (p > 0.05). Conclusion: Magnetic resonance imaging (MRI) is an effective method for immediate efficacy evaluation of rabbit renal VX2 tumors after MWA and can serve as a valuable reference for the clinical assessment of post-ablative renal tumors.