Percutaneous Microwave Ablation For Treatment Research Articles

Percutaneous Microwave Ablation for Treatment of Retroperitoneal Tumors.

Purpose To determine if microwave ablation (MWA) of retroperitoneal tumors can safely provide high rates of local tumor control. Materials and Methods This retrospective study included 19 patients (median age, 65 years [range = 46-78 years]; 13 [68.4%] men and six [31.6%] women) with 29 retroperitoneal tumors treated over 22 MWA procedures. Hydrodissection (0.9% saline with 2% iohexol) was injected in 17 of 22 (77.3%) procedures to protect nontarget anatomy. The primary outcomes evaluated were local tumor progression (LTP) and complication rates. Oncologic outcomes, including overall survival (OS), progression-free survival (PFS), and treatment-free interval (TFI), were examined as secondary outcome measures. Results Median follow-up was 18 months (range = 0.5-113). Hydrodissection was successful in displacing nontarget anatomy in 16 of 17 (94.1%) procedures. The LTP rate was 3.4% (one of 29; 95% CI: 0.1, 17.8) per tumor and 5.3% (one of 19; 95% CI: 0.1, 26.0) per patient. The overall complication rate per patient was 15.8% (three of 19), including two minor complications and one major complication. The OS rate at 1, 2, and 3 years was 81.8%, 81.8%, and 72.7%, respectively, with a median OS estimated at greater than 7 years. There was no evidence of a difference in OS (P = .34) and PFS (P = .56) between patients with renal cell carcinoma (six of 19 [31.6%]) versus other tumors (13 of 19 [68.4%]) and patients treated with no evidence of disease (15 of 22 [68.2%]) versus patients with residual tumors (seven of 22 [31.8%]). Median TFI was 18 months (range = 0.5-108). Conclusion Treatment of retroperitoneal tumors with MWA combined with hydrodissection provided high rates of local control, prolonged systemic therapy-free intervals, and few serious complications. Keywords: Ablation Techniques (ie, Radiofrequency, Thermal, Chemical), Retroperitoneum, Microwave Ablation, Hydrodissection © RSNA, 2024.

Role of Percutaneous Microwave Ablation in Treatment of Osteoid Osteoma

Role of Percutaneous Microwave Ablation in Treatment of Osteoid Osteoma

Application of oxytocin in ultrasound-guided percutaneous microwave ablation for treatment of hypervascular uterine fibroids: a preliminary report

Objective: This study evaluated the effect of oxytocin administration prior to microwave ablation (MWA) of hypervascular uterine fibroids.Methods: Thirty-two patients with 38 hypervascular uterine fibroids (Adler blood flow grade 3) were equally apportioned to receive intravenous oxytocin infusion (0.32 U/min) 20 min before ultrasound-guided percutaneous MWA, or no oxytocin (control). Changes in Adler blood supply grade and myoma volume were observed via color Doppler ultrasonography (CDU). All patients underwent quantitative ablation with single or double needle and microwave power 50 W (180 s). Treatment continued for those who did not reach the therapeutic goal. The myoma necrotic volume was evaluated by contrast-enhanced ultrasound. Ablation rate was the percent of MRI nonenhanced myoma volume after treatment, relative to myoma volume before treatment, 2 days after surgery.Results: Twenty minutes after oxytocin administration, CDU showed significant decrease of blood vessels in myomas, and Adler blood supply decreased from grade 3 to grade 1 or grade 0 in 10 and 9 myomas, respectively. Myoma volumes were reduced by 2.12 ± 0.24%. Necrotic volumes in the oxytocin (control) groups were 36.96 ± 2.78 cm3 (22.68 ± 3.38 cm3) and ablation rates were 95.4 ± 2.7% (85.7 ± 3.3%; t = 12.68, 8.866, p = 0.001, both). No serious complication was noted.Conclusion: Intravenous oxytocin administered before percutaneous MWA of hypervascular uterine fibroids can effectively block the blood supply vessels of the myoma, reduce the heat sink effect, and thereby increase the ablation volume and improve the local therapeutic effect.

Computed tomography-guided percutaneous microwave ablation for treatment of peripheral ground-glass opacity-Lung adenocarcinoma: A pilot study.

The purpose of the study is to retrospectively evaluate the safety and efficacy of microwave ablation (MWA) for the treatment of ground-glass opacity (GGO)-lung adenocarcinoma. From December 2013 to June 2017, a total of 51 patients (22 males and 29 females, mean age of 69.4 ± 10.1 years) were included in this study, with 51 lung adenocarcinoma lesions showing GGO (mean long-axis diameter of 18.7 ± 6.05 mm). They received a total of 52 sessions of percutaneous computed tomography-guided (CT-guided) MWA. First, lung adenocarcinoma with GGO was histologically defined by needle biopsy under the guidance of CT. Second, the efficacy of CT-guided MWA was analyzed, including the feasibility, safety, 3 years local progression-free survival (LPFS), 3 years disease-specific survival, and 3 years overall survival (OS). Final, complications after MWA were also summarized. The technical success rate was 100%, without MWA procedure-related death. At the median follow-up period (27.02, range: 7-45 months), the rates of 3 years LPFS, cancer-specific survival, and OS were 98%, 100%, and 96%, respectively. The complications after MWA included pneumothorax (48.1%, 25/52), hemoptysis (28.8%, 14/52), pleural effusion (23.1%, 12/52), and pulmonary infection (7.7%, 4/52). CT-guided percutaneous MWA was a feasible, safe, and effective therapeutic approach for treating GGO-lung adenocarcinoma.

Percutaneous microwave ablation of type I substernal goiter under ultrasonic guidance

Objective To investigate the feasibility and clinical effect for percutaneous microwave ablation of type I substernal goiter under the guidance of ultrasound. Methods Thirteen patients with type I substernal goiter were selected. All patients underwent percutaneous microwave ablation treatment under the guidance of ultrasound. Thirteen patients with 47 medals nodules were performed ultrasound guided percutaneous microwave ablation. Intraoperativeheat blocking blood flowwas used to prevent severe hemorrhage.Liquid isolation beltandleverage frommethods were used to effectively prevent surrounding important structures against heat damage.Small amount of residual methodwas used to avoid tracheal collapse. All patients were followed up post-operative 1, 3, 6, 12 months by monitoring of thyroid nodule volume change, adverse reactions, and postoperative complications. Results Thirteen patients with 47 medals nodules were successfully performed percutaneous microwave ablation guided by ultrasound. Among them, 2 patients performed the second treatment for too large volume of goiter, tracheal displacement and poor physical tolerance of older. The postoperative ultrasound contrast and color Doppler showed that the lesions were completely inactivated. No obvious complications occurred in all 13 patients, and no permanent hoarseness occured. The symptoms of cervical oppression and discomfort disappeared for all patients within 1-4 months after surgery. Thirteen patients were followed up for 12 months after the operation. The thyroid function was normal and the volume reduction rate of thyroid nodules was (85±31)%. Conclusions Percutaneous microwave ablation of type I substernal goiter under ultrasonic guidance is a safe and effective method to reduce the thyroid nodules with no serious complications. It is worth to be popularized in clinical practice. Key words: Ultrasonography; Microwave/therapeutic use; Goiter, substernal

Application of ultrasound-guided percutaneous microwave ablation treatment in patients with benign thyroid nodules

Objective To investigate the effectiveness and safety of ultrasound-guided percutaneous microwave ablation in the treatment of benign thyroid nodules. Methods A total 456 patients (912 nodules) underwent microwave ablation in our department. Microwave ablation was carried out using microwave antenna under local anesthesia. Nodule volume, thyroid function and clinical symptoms were evaluated before treatment and at 1, 3, 6 and 12 months after the treatment to monitor changes in the volume, adverse effect and complications. Results 912 nodules were all studied with contrast-enhanced ultrasound immediately after the ablation, and all results showed black hole sign. The mean follow-up period after microwave ablation was (9±6)months (range, 3-24 months). At 6-month follow-up, the mean volume reduction ratio of the solid nodules, mixed nodules and the cystic nodules was (61±50)%, (81±33)%, (89±46)%, respectively. The treatment was well tolerated and no major complications were observed except pain and transient voice changes (2.4%). Conclusions Microwave ablation is a safe and effective technique for the treatment of benign thyroid nodules. Key words: Ultrasonography; Microwave/therapeutic use; Thyroid nodule

Ultrasound-Guided Percutaneous Microwave Ablation Treatment of Initial Recurrent Hepatocellular Carcinoma after Hepatic Resection: Long-Term Outcomes

This study aimed to evaluate the long-term outcomes after percutaneous microwave ablation (MWA) for patients with initial recurrent hepatocellular carcinoma (HCC) measuring ≤5 cm in diameter after hepatectomy. From May 2005 to December 2011, 89 patients with 116 initial recurrent HCCs after hepatectomy treated with percutaneous MWA were included in the study. One mo after MWA, the complete ablation rate was 91.0% (81/89). At 1, 3, 5 and 7 y, the respective overall and recurrence-free survival rates after percutaneous MWA were 73.3%, 53.7%, 39.6% and 17.3% and 58.5%, 26.4%, 22.0% and 11.0%. The cumulative incidence of local tumor progression (LTP) and the intra-hepatic distant recurrence (IDR)–free survival rates after MWA were 9.1%, 14.6%, 18.3% and 18.3% and 62.9%, 32.3%, 26.9% and 13.5% at 1, 3, 5 and 7 y, respectively. The multivariate analysis indicated that multiple tumors (p = 0.006), a poor Child-Pugh score (p = 0.003), serum α-fetoprotein (AFP) >100 ng/mL (p = 0.002), and MWA treatment failure (p = 0.000) were risk factors that significantly affected overall survival, and MWA treatment failure (p = 0.000) was a risk factor that significantly affected IDR-free survival. In conclusion, percutaneous MWA is an effective therapeutic technique for initial recurrent HCC measuring ≤5 cm in diameter after hepatectomy.

Computed tomography-guided percutaneous microwave ablation treatment for lung metastases from nasopharyngeal carcinoma.

The objective of this retrospective study was to evaluate the safety and efficacy of percutaneous microwave ablation (MWA) for treating lung metastases from nasopharyngeal carcinoma (NPC). From December 2012 to November 2014, 17 patients (15 males, and two females, averaged 45.7 years old) with lung metastases from NPC accepted computed tomography (CT)-guided percutaneous MWA. The average number of lung metastases was 1.7 (range: 1-4), and the biggest tumor diameter was 4.2 cm (range: 0.8-4.2 cm). Nineteen nodules located in the right lung and 10 nodules located in the left lung. A total of 29 ablation sites were performed to 29 lung metastases in 22 MWA sessions. Postoperative assessments of complete tumor necrosis rate, safety, local tumor progression, and survival period were carried out. Of the 29 lesions, complete response was achieved for 27 lesions; residual tumor was found in one lesion 3 months postoperatively; and another lesion was found enlarged 3-month postoperatively with obvious enhancement. Four patients had a small amount of postoperative parenchyma bleeding and two patients had a small amount of pneumothorax. Six months after MWA treatment, new metastatic lesions appeared in six patients, five patients had new metastatic lesions inside the lung, and the other patient had metastatic lesions in the thoracic vertebra. The time for the appearance of new pulmonary metastases for the five patients was 4-20 months, averaged 7.2 months. CT-guided MWA is a promising treatment alternative for local tumor control in selected patients with lung metastases from NPC.

Role of Percutaneous Microwave Ablation in Treatment of Hepatocellular Carcinoma

Introduction: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with an annual occurrence of one million new cases. An etiologic association between HBV infection and the development of HCC has been established. Hepatitis C virus is also proving an important predisposing factor for this malignancy, the use of minimally invasive Percutaneous ablative technique (e.g. Radiofrequency (RF) and Microwave ablation (MW) has gained great momentum and because of the drawbacks of RF ablation, several groups have successfully proved the efficacious nature of Microwave ablation in the treatment of hepatocellular carcinoma. Aim of the Work: The aim of this work is to highlight the role, the principles and the applications of percutaneous Microwave Ablation in Hepatocellular carcinoma. Methods: The studied group included 30 patients (25 men and 5 women) with hepatocellular carcinoma. All patients underwent microwave ablation for the hepatocellular carcinoma. Results: The results of the procedures will be assessed as regarding sizeand enhancement of the lesion (s) on triphasic CT abdomen before the procedure and at the follow up at one month as well as the Alpha fetoprotein levels. Conclusion: MWA technique represents a safe, fast and efficacious way to perform hepatic ablation in patients with HCC. Initial results are encouraging; however, longer follow-up is needed for further classification of our results.

The clinical value of ultrasound elastography in evaluating uterine leiomyomas and adenomyosis treated with percutaneous microwave ablation

Objective To study the clinical value of ultrasound elastography in evaluating the ablated zone and morphology of uterine leiomyoma and adenomyosis treated with percutaneous microwave ablation treatment(PMAT) under ultrasound guidance.Methods Eighteen patients were randomly chosen from 150 patients with symptoms uterine leiomyomas or adenomyosis who were treated with PMAT.Contrastenhanced Ultrasound(CEUS) and ultrasound elastography were performed before and immediately after PMAT.Compared with contrast enhanced MR were performed at 1 - 2 d after PMAT,the accuracy of ultrasound elastography and CEUS in evaluating the ablated range of PMA were analysed.Results Ultrasound elastography showed that the ablated zone was blue and the boundary with the surrounding tissues was clear.The ablated zone showed no enhancement with CEUS and enhanced MR.The mean diameter of the ablated zone in ultrasound elastography,CEUS,and contrast enhanced MR was (4.90 ±1.12)cm,(4.64 ± 0.93) cm,and (4.89 ± 1.02) cm,respectively.The diameter in ultrasound elastography was slightly larger than that in CEUS ( P =0.02) and had no statistical difference with that in contrast enhanced MR ( P =0.44).Conclusions Ultrasound elastography can accurately show the coagulation range immediately after PMAT and is supposed to be a method to evaluate the ablated zone noninvasively immediately after PMAT. Key words: Ultrasonography; Microbubbles; Leiomyoma; Adenomyoma; Microwave/therapeuticuse; Elastography

OP08.08: Study on clinical effect of ultrasound‐guided percutaneous microwave ablation for treatment of adenomyosis

OP08.08: Study on clinical effect of ultrasound‐guided percutaneous microwave ablation for treatment of adenomyosis

915 MHz microwave ablation with implanted internal cooled-shaft antenna: Initial experimental study in in vivo porcine livers

Purpose To explore a preferred power output for further clinical application based on the ablated lesions induced by the four power outputs of 915 MHz microwave in experimental study of in vivo porcine livers. Materials and methods A KY2000-915 microwave ablation system with an implanted 915 MHz internal cooled-shaft antenna was used in this study. A total of 24 ablations were performed in eight in vivo porcine livers. The energy was applied for 10 min at microwave output powers of 50 W, 60 W, 70 W, and 80 W. Long-axis and short-axis diameters of the coagulation zone were measured on all gross specimens. Results The shapes of the 915 MHz microwave ablation lesions were elliptical commonly. As the power increased, the long-axis and short-axis diameters of the coagulation zone had a tendency to rise. But the long-axis diameter of the ablated lesion at 50 W was not significantly smaller than that of the ablated lesion at 60 W ( P > 0.05) and there were no statistical differences in short-axis diameters of the ablated lesion among the three power outputs of 60 W, 70 W and 80 W ( P > 0.05). After 10 min irradiation of 60 W, the long-axis and short-axis diameters of the coagulation zone were 5.02 ± 0.60 cm and 3.65 ± 0.46 cm, respectively. Conclusions For decreasing the undesired damages of liver tissues along the shaft and the number of antenna in further clinically percutaneous microwave ablation treatment, the power of 60 W may be a preferred setting among the four power outputs used in present study.

Ultrasonography-guided percutaneous microwave ablation of peripheral lung cancer

The aim of this study was to evaluate the feasibility and therapeutic effectiveness of ultrasonography (US)-guided percutaneous microwave ablation (PMA) in the treatment of peripheral lung cancer. From December 2002 to September 2003, 12 Chinese patients with 16 histologically proven lung malignant tumors (6 primary and 10 metastatic) were treated with US-guided PMA. All tumors were located at the peripheral portions of the lung where the tumors were in direct contact with visceral pleura and visualized on US. A total of 21 insertions with 25 applications was administered to the 16 tumors. There was no radiation or chemotherapy combined with PMA. Based on the follow-up period of 6-40 months (average=20 months), seven patients survived without serious complications and five patients died from metastasis after PMA. The size of treated tumors was decreased in all cases (10 tumors with moderate to remarkable area reduction and 6 tumors with mild area reduction). Blood flow in the tumors became either invisible or diminished on color Doppler flow imaging, which showed 9 tumors with no enhancement and 7 tumors with partially decreased enhancement on contrast-enhanced computed tomography after PMA. All patients experienced improvement of clinical symptoms after PMA treatment. Ultrasonography-guided PMA, a mildly invasive procedure, is an effective, safe, and feasible method for treating peripheral lung tumors. Percutaneous microwave ablation provides an alternative therapy for patients with inoperable peripheral lung cancer as well as for patients who refuse radiation or chemotherapy.