Image-guided Percutaneous Microwave Ablation Research Articles

Clinical Impact of a Protocol Involving Cone-Beam CT (CBCT), Fusion Imaging and Ablation Volume Prediction in Percutaneous Image-Guided Microwave Ablation in Patients with Hepatocellular Carcinoma Unsuitable for Standard Ultrasound (US) Guidance.

to evaluate the clinical impact of a protocol for the image-guided percutaneous microwave ablation (MWA) of hepatocellular carcinoma (HCC) that includes cone-beam computed tomography (CBCT), fusion imaging and ablation volume prediction in patients with hepatocellular carcinoma unsuitable for standard ultrasound (US) guidance. this study included all patients with HCC treated with MWA between January 2021 and June 2022 in a tertiary institution. Patients were divided into two groups: Group A, treated following the protocol, and Group B, treated with standard ultrasound (US) guidance. Follow-up images were reviewed to assess residual disease (RD), local tumor progression (LTP) and intrahepatic distant recurrence (IDR). Ablation response at 1 month was also evaluated according to mRECIST. Baseline variables and outcomes were compared between the groups. For 1-month RD, propensity score weighting (PSW) was performed. 80 consecutive patients with 101 HCCs treated with MWA were divided into two groups. Group A had 41 HCCs in 37 patients, and Group B had 60 HCCs in 43 patients. Among all baseline variables, the groups differed regarding their age (mean of 72 years in Group A and 64 years in Group B, respectively), new vs. residual tumor rates (48% Group A vs. 25% Group B, p < 0.05) and number of subcapsular tumors (56.7% Group B vs. 31.7% Group A, p < 0.05) and perivascular tumors (51.7% Group B vs. 17.1% Group A, p < 0.05). The protocol led to repositioning the antenna in 49% of cases. There was a significant difference in 1-month local response between the groups measured as the RD rate and mRECIST outcomes. LTP rates at 3 and 6 months, and IDR rates at 1, 3 and 6 months, showed no significant differences. Among all variables, logistic regression after PSW demonstrated a protective effect of the protocol against 1-month RD. The use of CBCT, fusion imaging and ablation volume prediction during percutaneous MWA of HCCs provided a better 1-month tumor local control. Further studies with a larger population and longer follow-up are needed.

Cone-beam computed tomography image-guided percutaneous microwave ablation for lung nodules in a hybrid operating room: an initial experience.

The experience of thermal ablation of lung lesions is limited, especially performing the procedure under localisation by cone-beam CT in the hybrid operation room (HOR). Here, we present the experience of microwave ablation (MWA) of lung nodules in the HOR. We reviewed patients who underwent image-guide percutaneous MWA for lung nodules in the HOR under general anaesthesia between July 2020 and July 2022. The workflow in the HOR including the pre-procedure preparation, anaesthesia consideration, operation methods, and postoperative care was clearly described. Forty lesions in 33 patients who underwent MWA under general anaesthesia (GA) in the HOR were analysed. Twenty-seven patients had a single pulmonary nodule, and the remaining six patients had multiple nodules. The median procedure time was 41.0 min, and the median ablation time per lesion was 6.75 min. The median global operation room time was 115.0 min. The median total dose area product was 14881 μGym2. The median ablation volume was 111.6 cm3. All patients were discharged from the hospital with a median postoperative stay of 1 day. Four patients had pneumothorax, two patients had pleural effusion during the first month of outpatient follow-up, and one patient reported intercostal neuralgia during the 3-month follow-up. Thermal ablation of pulmonary nodules under GA in the HOR can be performed safely and efficiently if we follow the workflow provided. The procedure provides an alternative to managing pulmonary nodules in patients. Thermal ablation of pulmonary nodules under GA in the HOR can be performed safely and efficiently if the provided workflow is followed. • We tested the feasibility of microwave ablation of lung lesions performed in a hybrid operating room. • To this end, we provide a description of microwave ablation of the lung under cone-beam CT localisation. • We describe a workflow by which ablation of the pulmonary nodule can be performed safely under general anaesthesia.

Outpatient percutaneous image-guided microwave ablation with monitored anesthesia care: An exploratory study

PurposeTo evaluate the feasibility, safety, and periprocedural perception of pain for a combination approach of moderate and deep sedation for image-guided percutaneous microwave ablation of both primary and secondary malignant lesions. MethodsThis was a retrospective study of 33 image-guided percutaneous microwave ablation procedures performed on 33 patients in an outpatient-based interventional radiology center. We used a combination of midazolam, fentanyl, propofol, and/or ketamine to achieve mild to moderate sedation for the procedure, and also to achieve deeper sedation as needed for the ablation portion. ResultsTechnical success was achieved in all image-guided percutaneous microwave ablation procedures. Mean procedural time was 49.4 min. There were no major complications. Intraprocedural pain was absent in all patients. All 33 patients were deemed fit for discharge within 30 min following the procedure. ConclusionThe combination approach of moderate and deep sedation for anesthesia during image-guided percutaneous microwave ablation is an advantageous option. This approach has a strong safety profile, good technical success, short procedure times, low levels of intraprocedural and post-procedural pain, and short recovery from anesthesia.

Safety and Efficacy Outcomes From a Single-Center Study of Image-Guided Percutaneous Microwave Ablation for Primary and Metastatic Lung Malignancy

IntroductionImage-guided percutaneous microwave ablation (MWA) is becoming a more common treatment option for patients with primary and metastatic lung malignancies. Nevertheless, there is limited literature on the safety and efficacy of MWA compared with standard-of-care therapy, including surgical resection and radiation. This study will report the long-term outcomes after MWA for pulmonary malignancies and investigate the factors related to efficacy, including lesion size, location, and ablation power. MethodsRetrospective single-center study analyzing 93 patients who underwent percutaneous MWA for primary or metastatic lung malignancies. Outcomes included immediate technical success, local tumor recurrence, overall survival, disease-specific survival, and complications. ResultsAt a single institution, 190 lesions (81 primary and 109 metastatic) were treated in 93 patients. Immediate technical success was achieved in all cases. Freedom from local recurrence was 87.6%, 75.3%, and 69.2% and overall survival was 87.7%, 76.2%, and 74.3% at 1 year, 2 years, and 3 years, respectively. Disease-specific survival was 92.6%, 81.8%, and 81.8%. The most common complication was pneumothorax, which occurred in 54.7% (104 of 190) of procedures, with 35.2% (67 of 190) requiring a chest tube. No life-threatening complications occurred. ConclusionsPercutaneous MWA seems safe and effective for treatment of primary and metastatic lung malignancies and should be considered for patients with limited metastatic burden and lesions less than 3 cm in size.

Feasibility of Controlling Metastatic Osseous Pain Using Three Kinds of Image-Guided Procedures for Thermal Microwave Ablation: A Retrospective Study.

ObjectivesTo evaluate the feasibility and safety of treating painful osseous metastases using image‐guided percutaneous thermal microwave ablation.MethodsThis is a retrospective study of patients treated from December 2016 to December 2019 in one institute. A total of 50 patients (35 men, 15 women; mean age 55.24 ± 11.03 years) with 56 osseous metastatic lesions underwent image‐guided percutaneous microwave ablation. There were 7 patients with multiple and 43 patients with single metastases. The numbers of patients with primary cancer were as follows: lung, 13; liver, 17; kidney, 10; prostate, 1; breast, 3; osteosarcoma, 1; and thyroid, 5. Seventeen patients had cancer combined with soft tissue masses. The radiological images for the ablative procedures were obtained by CT, fluoroscopy with ultrasound, and fluoroscopy alone in 16, 11, and 23 patients, respectively. Pain severity was estimated using the visual analogue scale before and after treatment (1 week, 1 month, and 3 months after treatment). Radiological evaluations were performed at baseline and 3 months after the procedure.ResultsIn all patients, pain reduction occurred from the first day after treatment. Pain did not recur during the 3 months of follow up. The mean total ablation time per microwave electrode was 3.99 ± 2.48 min (range, 1–15 min). The mean power of the microwave electrode was 66.40 ± 12.08 W. The average volume of bone (load‐bearing bone, such as vertebra and acetabulum) cement after ablation was 2.82 ± 0.81 mL. There were no significant differences in visual analogue scale pain scores for different imaging techniques or ablation energies. No procedure‐related complications occurred.ConclusionImage‐guided percutaneous thermal microwave ablation of osseous metastases relieves pain and improves mobility. CT remains the first choice for percutaneous ablation. Fluoroscopy combined with ultrasound is effective for cases with soft tissue masses; fluoroscopy is also suitable for combination with vertebroplasty. However, further investigations are required.

Percutaneous microwave ablation therapy of renal cancer local relapse after radical nephrectomy: a feasibility and efficacy study.

Renal cell carcinoma (RCC) local recurrence after radical nephrectomy is uncommon. When feasible, surgical removal remains the primary treatment strategy; nevertheless, local RCC relapse management is controversial, and less invasive procedures may represent an attractive option to achieve oncologic control. The aim of our study was to assess the feasibility, safety, and clinical outcomes of image-guided percutaneous microwave ablation (MWA) for RCC local recurrence in patients initially treated with nephrectomy with curative intent. 10 consecutive patients underwent CT-guided percutaneous MWA of a total of 10 retroperitoneal nodules. Inclusion criteria were: histologically verified retroperitoneal metastases, previous radical nephrectomy, lesion no larger than 3cm, no other metastatic site elsewhere. All the procedures were performed under moderate sedation choosing the most favorable patient decubitus. If deemed necessary, pneumodissection was induced before ablation. After the antenna placement inside the target lesion, thermal ablation was achieved by maintenance of a power of 100W for a total time between 2 and 4min. All patients were observed overnight and discharged the following day if clinically stable. Technical success was obtained in 100% of patients. One patient was re-treated to complete oncologic response with repeat MWA. No major complications were observed. No patients demonstrated local recurrence at a mean follow-up of 26months. MWA is a safe and effective treatment strategy for loco-regional relapse of RCC following radical nephrectomy. This technique may represent a valuable approach for patients who are not eligible for surgery.

Image-Guided Percutaneous ‎Microwave Ablation Versus Cryoablation For Hepatocellular Carcinoma In High-Risk Locations: Intermediate-Term Results.

ObjectiveThe aims of this study were to compare the clinical outcomes between image-guided percutaneous microwave ablation (MWA) and cryoablation (CRA) in patients with hepatocellular carcinoma (HCC) in high-risk locations and to identify the prognostic factors associated with the two treatment methods.MethodsThis retrospective study was institutional review board approved. A total of 120 patients (88 men and 32 women) with one hundred and thirty-four HCC lesions in high-risk locations from April 2014 to March 2018 were reviewed. Sixty-four patients underwent MWA and 56 patients underwent CRA. Survival, recurrence and complications were compared between the two groups. Effect of changes in key outcomes (i.e., overall survival (OS), recurrence-free survival (RFS) and local tumor progression (LTP)) was statistically analyzed with the log rank test. Univariate and multivariate analysis were performed on clinicopathological variables to identify factors affecting intermediate-term outcomes.ResultsThe OS and RFS after MWA were comparable to those of CRA (P =0.141, and P=0.469, respectively). The LTP and major complication in MWA group was higher than those in CRA group (P=0.003, and P=0.039). Univariate analysis showed that age (P=0.007), tumor size (P=0.001), and Child-Turcotte-Pugh (CTP) grade (P=0.003) were risk factors for OS, and multivariate analysis results showed that older age (≥65 years) (P=0.002, HR:3.338, 95% CI:1.928–5.281), 3.0–5.0 cm in size (P<0.001, HR: 3.312, 95% CI: 1.872–4.489) and CTP grade B (P=0.001, HR:3.382, 95% CI: 1.882–5.902) were independently associated with poor OS.ConclusionCRA had comparable oncologic outcomes with MWA and could be a safe and effective treatment for HCC in high-risk locations.

Microwave ablation of osteoid osteoma: initial experience and efficacy.

Image-guided percutaneous microwave ablation has been used to treat adult osteoid osteomas but has not been thoroughly evaluated in the pediatric population. To evaluate the technical feasibility and clinical efficacy of microwave ablation to treat osteoid osteomas in pediatric patients. The electronic medical record and imaging archive were reviewed for 24 consecutive patients who had undergone microwave ablation of osteoid osteomas between January 1, 2015, and May 31, 2018, at a single tertiary care pediatric hospital. All patients were diagnosed by clinical and imaging criteria, and referred by a pediatric orthopedic surgeon after failing conservative management with pain medication. The average age of the patients was 13.3years (range: 3-18years), and the average size of the osteoid osteoma nidus was 8.8mm (range: 5-22mm). Technical success was defined as placement of the microwave antenna at the distal margin of the lesion nidus and achievement of the target ablation temperature. Clinical findings were assessed pre- and post-ablation and clinical success was defined as complete relief of pain without pain medication at 1-month follow-up. The number and severity of complications were also documented. Clinical success was achieved in 100% of patients (24/24), with all reporting complete cessation of pain medication use 1week after treatment and 0/10 pain at 1month. There were 4 minor complications (17%) including access site numbness and a minor soft-tissue infection. There were no major complications. Microwave ablation is a technically feasible and clinically effective treatment for pediatric osteoid osteomas.

Percutaneous microwave ablation of renal angiomyolipomas in tuberous sclerosis complex to improve the quality of life: preliminary experience in an Italian center.

To evaluate efficacy, safety and quality of life of the patients with renal angiomyolipomas (AMLs) associated with tuberous sclerosis complex (TSC) treated with percutaneous microwave ablation (MWA). Nine patients (7 females and 2 males; mean age 27.6years, range 23-34), with 10 renal AMLs with a mean size of 6.3cm (range 4.5-8.5) were treated with image-guided percutaneous MWA. Indications for treatment were the risk of rupture/hemorrhage due to size greater than 4cm and symptomatology; in one case, a previous hemorrhage was the indication for treatment. During follow-up, the volume of the ablated AMLs and its relationship with the relief of symptoms were registered. Technical and clinical success, safety, and quality of life (QOL) were evaluated in a mean follow-up of 9months (range 3-12). Technical success was obtained in all cases. Clinical success was obtained in all cases; the volume of the ablated AMLs was not related with symptoms relief; all patients referred a significant improvement in their QOL, with a regularization of daily activities. There were no major procedural complications or delayed adverse events. A small self-limited post-procedural subcapsular hematoma was registered. Post-ablation syndrome was registered in 5 cases and was self-limited in all cases. Symptoms relief, lower risk of hemorrhage and a normalized QOL were obtained in all patients with a safe and mini-invasive procedure.

An Overview of Image-Guided Percutaneous Microwave Ablation of Renal Cell Carcinoma

An Overview of Image-Guided Percutaneous Microwave Ablation of Renal Cell Carcinoma

Efficacy and Safety of Microwave Ablation for Malignant Renal Tumors: An Updated Systematic Review and Meta-Analysis of the Literature Since 2012.

ObjectiveTo systematically determine the treatment outcomes of percutaneous microwave ablation (MWA) in patients with malignant renal tumor.Materials and MethodsOriginal studies that reported the clinical outcomes of MWA in patients with malignant renal tumors were identified in MEDLINE and EMBASE from 2012 to June 30, 2017. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic summary estimates of various clinical outcomes, including technical outcomes (technical success rate [TSR] and technical efficacy rate [TER]), oncologic outcomes (local tumor recurrence rate [LRR], cancer-specific survival rate [CSSR], and overall survival rate [OSR]), and complications.ResultsAmong the 145 articles screened, 13 articles including 567 patients carrying 616 malignant renal tumors were included in the meta-analysis. The meta-analytic pooled TSR and TER were 97.3% (95% confidence interval, 94.3–99.4%; I2 = 0.0%) and 97.6% (95.0–99.4%, I2 = 48.5%), respectively. The meta-analytic pooled LRR was 2.1% (0.3–4.7%, I2 = 54.1%). At 1-, 2-, 3-, and 5-year follow-up time points, the meta-analytic pooled CSSRs were 99.1% (97.2–100.0%; I2 = 0.0%), 98.4% (95.1–100.0%; I2 = 31.2%), 97.6% (93.4–99.9%; I2 = 52.3%), and 96.9% (93.3–99.2%; I2 = 0.0%) respectively, while the OSRs were 98.3% (96.1–99.8%; I2 = 0.0%), 94.9% (91.7–97.5%; I2 = 0.0%), 86.8% (81.9–91.1%; I2 = 22.1%), and 81.9% (75.4–87.6%; I2 = 0.0%). In terms of major complications, a 1.8% (0.6–3.3%; I2 = 0.0%) rate of meta-analytic pooled incidence was found.ConclusionMicrowave ablation showed favorable technical and oncologic outcomes with a low incidence of major complications. Hence, image-guided percutaneous MWA can be considered as a safe and effective treatment for malignant renal tumors.

Ultrasonography-guided percutaneous microwave ablation for large hepatic cavernous haemangiomas

Purpose: To evaluate the efficacy and safety of ultrasound-guided percutaneous microwave ablation (MWA) for large hepatic cavernous haemangiomas (HCHs) with ablation of the feeding artery and aspiration of blood from haemangioma simultaneously.Materials and methods: From January 2011 to December 2016, 40 patients (29 females, 11male; average age 43.25 ± 7.65 years) with 42 giant hepatic haemangiomas (mean diameter 7.02 ± 1.55 cm, range 4.1–10.8 cm) were treated with image-guided percutaneous MWA with ablation of the feeding artery and aspiration of blood from haemangioma simultaneously. After MWA, therapeutic efficacy was assessed by contrast-enhanced imaging during follow-up. Median follow-up time was 24 months (range 6–60 months).Results: Technical effectiveness rate was 100% with a mean ablation time of 1175 ± 516 (range 480–2340) seconds. The mean number of antenna insertions was 3.82 ± 1.23 for each lesion. Clinical effectiveness rate was 95% (38/40). There was a significant decrease of the tumour volume within three days after ablation compared with before ablation (p < 0.001). The mean tumour volume shrinkage rate was 59.67 ± 16.73% (range 28.20–89.72%) within three days after ablation. Minor complications mainly included fever, transient elevation of transaminase, pleura effusion, and haemoglobinuria. One patient developed a major complication with acute kidney injury (AKI) shortly after MWA, whose renal function gradually recovered after haemodialysis. No other severe complications occurred in perioperative and follow-up periods.Conclusions: Ultrasound-guided percutaneous MWA for large HCHs with ablation of the feeding artery and aspiration of blood from haemangioma simultaneously is safe and effective.

Image-guided percutaneous microwave ablation of small renal tumours: short- and mid-term outcomes.

The purpose is to assess the short- and mid-term outcomes of microwave ablation (MWA) of small renal tumours in selected patients. From August 2012 to February 2015, 29 renal tumours in 23 patients (17 male, 6 female, mean age 75 years) were treated by percutaneous MWA under imaging guidance. The tumours were 1-4.7 cm in diameter (mean size, 2.7 cm). Therapeutic effects were assessed at follow-up with magnetic resonance imaging (MRI). All patients were followed up for 2-25 months (mean, 12.2 months) to observe the therapeutic effects and complications. Changes in renal function at day 1 after treatment were statistically analyzed using the Student paired t-test or the paired Wilcoxon test. Technical success was achieved in all cases. One severe bleeding complication post-procedure occurred leading to death. No other unexpected side effects were observed after the MWA procedures. Clinical effectiveness was 100%. None of the patients showed recurrence on MRI imaging follow-up. No significant changes in renal function were noted after treatment (P=0.57). Our preliminary study demonstrates that the use of MWA for the treatment of small renal tumours can be applied as safely and efficiently as other ablative techniques in selected patients not eligible for surgery.

Efficacy, safety and effectiveness of image-guided percutaneous microwave ablation in cystic renal lesions Bosniak III or IV after 24 months follow up

Purpose of the studyThe aim of the study was to assess the efficacy, safety and effectiveness of percutaneous image-guided microwave ablation (MWA) in Bosniak category III or IV cystic renal lesions after 24 months follow-up duration. MethodsBetween May 2008 and December 2012, computed tomography (CT)- or ultrasound (US)-guided MWA was performed in 6 patients with 7 cystic renal lesions (range 13.8–27 mm, mean 17.02 mm, SD 8.5 mm) Bosniak catgegory III or IV. The number of treatment sessions, treatment results, lesion size changes and complications were evaluated. Technical success (TS), technical effectiveness (TE), local tumor progression rate (LTPR), cancer-specific survival rate (CSSR) and overall survival rate (OSR) were computed. Main findingsTS was 100% (7/7) and TE was 100%; LTPR was 0%; CSSR and OSR were 100%. No major complications were observed. ConclusionOur preliminary experience with MWA shows a potential role for US/CT-guided percutaneous MWA in treating Bosniak category III or IV cystic renal lesions, as a safe approach to treat selected patients not suitable for surgery.