Advances in Tumor Management: Harnessing the Potential of Histotripsy

Tissue ablation techniques have long been used in clinical settings to treat various oncologic diseases. However, many of these techniques are invasive and can cause substantial adverse effects. Histotripsy is a noninvasive, nonionizing, nonthermal tissue ablation technique that has the potential to replace surgical interventions in various clinical settings. Histotripsy works by delivering high-intensity focused ultrasound waves to target tissue. These waves create cavitation bubbles within tissues that rapidly expand and collapse, thereby mechanically fractionating the tissue into acellular debris that is subsequently absorbed by the body's immune system. Preclinical and clinical studies have demonstrated the efficacy of histotripsy in treating a range of diseases, including liver, pancreatic, renal, and prostate tumors. Safety outcomes of histotripsy have been generally favorable, with minimal adverse effects reported. However, further studies are needed to optimize the technique and understand its long-term effects. This review aims to discuss the importance of histotripsy as a noninvasive tissue ablation technique, the preclinical and clinical literature on histotripsy and its safety, and the potential applications of histotripsy in clinical practice. Keywords: Tumor Microenvironment, Ultrasound-High-Intensity Focused (HIFU), Ablation Techniques, Abdomen/GI, Genital/Reproductive, Nonthermal Tissue Ablation, Histotripsy, Clinical Trials, Preclinical Applications, Focused Ultrasound © RSNA, 2024.

Ablation techniques or active surveillance compared to surgical resection in patients with low-risk papillary thyroid cancer: a systematic review and meta-analysis

BACKGROUND

The global prevalence of thyroid cancer is on the rise. About one-third of newly diagnosed thyroid cancer cases comprise low-risk papillary thyroid cancer (1.5 cm or more minor). While surgical removal remains the prevailing approach for managing low-risk papillary thyroid cancer (LPTC) in patients, other options such as active surveillance (AS), radiofrequency ablation (RFA), microwave ablation (MWA), and laser ablation (LA) are also being considered as viable alternatives. This study evaluated and compared surgical thyroid resection (TSR) versus non-surgical (NS) methods for treating patients with LPTC.

METHODS

The study encompassed an analysis of comparisons between surgical thyroid resection (TSR) and alternative approaches, including active surveillance (AS), radiofrequency ablation (RFA), microwave ablation (MWA), or laser ablation (LA). The focus was on patients with biopsy-confirmed low-risk papillary thyroid cancer (LPTC) of less than 1.5 cm without preoperative indications of local or distant metastasis. The primary outcomes assessed were recurrence rates, disease-specific mortality, and quality of life (QoL). Data were collected from prominent databases, including Cochrane Database, Embase, MEDLINE, and Scopus, from inception to June 3rd, 2020. The CLARITY tool was utilized to evaluate bias risk. The analysis involved odds ratios (OR) with 95% confidence intervals (CI) for dichotomous outcomes, as well as mean differences (MD) and standardized mean differences (SMD) for continuous outcomes. The study is registered on PROSPERO under the identifier CRD42021235657.

RESULTS

The study incorporated 13 retrospective cohort studies involving 4034 patients. Surgical thyroid resection (TSR), active surveillance (AS), and minimally invasive techniques like radiofrequency ablation (RFA), microwave ablation (MWA), and laser ablation (LA) were performed in varying proportions of cases. The analysis indicated that specific disease mortality rates were comparable among AS, MWA, and TSR groups. The risk of recurrence, evaluated over different follow-up periods, showed no significant differences when comparing AS, RFA, MWA, or LA against TSR. Patients undergoing AS demonstrated better physical health-related quality of life (QoL) than those undergoing TSR. However, no substantial differences were observed in the overall mental health domain of QoL when comparing AS or RFA with TSR. The risk of bias was moderate in nine studies and high in four.

CONCLUSION

Low-quality evidence indicates comparable recurrence and disease-specific mortality risks among patients with LPTC who underwent ablation techniques or active surveillance (AS) compared to surgery. Nevertheless, individuals who opted for AS exhibited enhanced physical quality of life (QoL). Subsequent investigations are warranted to validate these findings.

Introducing ethanol ablation as a treatment for thyroid cysts in the emergency setting

BACKGROUND

Ethanol ablation for the treatment of thyroid cysts has been well documented in the literature as a safe, effective treatment option in the elective setting. This study demonstrates the use of ethanol ablation in the emergency setting.

METHODS

Three patients presenting with airway-threatening compressive symptoms secondary to a thyroid cyst were treated with ethanol ablation within 24 hours of presentation to hospital.

RESULTS

All patients had symptom resolution at a median of nine months follow up post procedure. Sixty-six per cent of patients required only one treatment. There was a median of 100 per cent radiological resolution of the cystic component. The median Glasgow Benefit Inventory score was +27.7, similar to that for tonsillectomy.

CONCLUSION

Ethanol ablation is a safe, cost-effective and efficient treatment option for thyroid cysts in the acute setting.

Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter

OBJECTIVE

We aimed to compare cryoballoon pulmonary vein isolation (PVI) with standard radiofrequency cavotricuspid isthmus (CTI) ablation as first-line treatment for typical atrial flutter (AFL).

METHODS

Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter was an international, multicentre, open with blinded assessment trial. Patients with CTI-dependent AFL and no documented atrial fibrillation (AF) were randomised to either cryoballoon PVI alone or radiofrequency CTI ablation. Primary efficacy outcome was time to first recurrence of sustained (>30 s) symptomatic atrial arrhythmia (AF/AFL/atrial tachycardia) at 12 months as assessed by continuous monitoring with an implantable loop recorder. Primary safety outcome was a composite of death, stroke, tamponade requiring drainage, atrio-oesophageal fistula, pacemaker implantation, serious vascular complications or persistent phrenic nerve palsy.

RESULTS

Trial recruitment was halted at 113 of the target 130 patients because of the SARS-CoV-2 pandemic (PVI, n=59; CTI ablation, n=54). Median age was 66 (IQR 61-71) years, with 98 (86.7%) men. At 12 months, the primary outcome occurred in 11 (18.6%) patients in the PVI group and 9 (16.7%) patients in the CTI group. There was no significant difference in the primary efficacy outcome between the groups (HR 1.11, 95% CI 0.46 to 2.67). AFL recurred in six (10.2%) patients in the PVI arm and one (1.9%) patient in the CTI arm (p=0.116). Time to occurrence of AF of ≥2 min was significantly reduced with cryoballoon PVI (HR 0.46, 95% CI 0.25 to 0.85). The composite safety outcome occurred in four patients in the PVI arm and three patients in the CTI arm (p=1.000).

CONCLUSION

Cryoballoon PVI as first-line treatment for AFL is equally effective compared with standard CTI ablation for preventing recurrence of atrial arrhythmia and better at preventing new-onset AF.

TRIAL REGISTRATION NUMBER

NCT03401099.

Impact of pre-existing left atrial appendage occluder on catheter ablation of atrial fibrillation

BACKGROUND

Patients with drug-refractory atrial fibrillation (AF) and pre-existing left atrial appendage occluder (LAAO) device may need pulmonary vein isolation (PVI). In this pioneer study, we investigated the impact of pre-existing LAAO on AF substrates and outcomes of PVI.

METHODS

From our AF registry, 65 drug-refractory patients with LAAO (72.1±11.4 years old; CHA₂DS₂-VASc score 3.7±2.1) were included for PVI. A balanced control group with 124 patients without LAAO receiving PVI (70.9±10.2 years old, CHA₂DS₂-VASc 3.6±1.9) were included for comparison.

RESULTS

We found PVI is feasible in patients with AF with pre-existing LAAO without new peridevice leak. Two patients with LAAO and one without LAAO had stroke during the procedure (2/65 vs 1/124, p=0.272). Complete isolation of left-sided PVs might not be achieved if the device covered the ridge joining the left atrial (LA) appendage to the body of LA. Local electrogram could be detected over LAAO and there was propagation of conduction over the occluder either under sinus rhythm or under atrial arrhythmia. LAAO might modulate LA substrate and induce peridevice fibrosis, peridevice LA flutter and complex fractionate atrial electrogram. The AF recurrent rate at 1 year was similar between the two groups (9.2% vs 8.8%).

CONCLUSIONS

This pioneer study first showed impacts of LAAO on LA substrate and PVI procedure.

First in-human modified atrial septostomy combining radiofrequency ablation and balloon dilation

OBJECTIVE

Preclinical research suggests that the combined use of radiofrequency ablation and balloon dilation (CURB) could create stable interatrial communications without device implantation. This study examined the first in-human use of CURB for modified atrial septostomy in patients with severe pulmonary arterial hypertension (PAH).

METHODS

Between July 2018 and October 2021, CURB was performed in 19 patients with severe PAH (age: 31.5±9.1 years; mean pulmonary artery pressure: 73 mm Hg (IQR: 66-92); pulmonary vascular resistance: 18.7 Wood units (IQR: 17.8-23.3)). Under guidance of intracardiac echocardiography and three-dimensional location system, (1) fossae ovalis was reconstructed and ablated point-by-point with radiofrequency; (2) then graded balloon dilation was performed after transseptal puncture and the optimal size was determined according to the level of arterial oxygen saturation (SatO₂); (3) radiofrequency ablation was repeated around the rims of the created fenestration. The interatrial fenestrations were followed-up serially.

RESULTS

After CURB, the immediate fenestration size was 4.4 mm (IQR: 4.1-5.1) with intracardiac echocardiography, systolic aortic pressure increased by 10.2±6.9 mm Hg, cardiac index increased by 0.7±0.3 L/min/m² and room-air resting SatO2 decreased by 6.2±1.9% (p<0.001). One patient experienced increased pericardiac effusion postoperatively; the others had no complications. On follow-up (median: 15.5 months), all interatrial communications were patent with stable size (intraclass correlation coefficient=0.96, 95%CI:0.89 to 0.99). The WHO functional class increased by 1 (IQR: 1-2) (p<0.001) with improvement of exercise capacity (+159.5 m, P<0.001).

CONCLUSION

The interatrial communications created with CURB in patients with severe PAH were stable and the mid-term outcomes were satisfactory.

TRIAL REGISTRATION NUMBER

NCT03554330.

Can Concomitant Bladder Neck Incision and Primary Valve Ablation Reduce Early Re-admission Rate and Secondary Intervention?

Objective:

To assess the effect of bladder neck morphology and its incision (BNI) in patients with posterior urethral valve (PUV) on early reintervention rate.

Patients and methods:

Infants undergoing PUV ablation (PVA) before 24 months of age and had at least 18 months of follow-up, were categorized into three groups according to the bladder neck appearance on baseline radiological and endoscopic examination: group 1; normal bladder neck underwent PVA, group 2; high bladder neck underwent PVA plus BNI, group 3; high bladder neck underwent PVA only. Early reintervention was defined as the need for check cystoscopy because of persistent renal function deterioration, worsening hydronephrosis and/or unsatisfactory VCUG improvement during the 1st six months post primary PVA.

Results:

Between 2000 and 2017, a total of 114 patients underwent PVA and met the study criteria with a median follow-up of 58 (18-230) months. For group 1, 16 (22.9%) patients needed readmission. Check cystoscopy was free and no further intervention was performed in 5(7.5%) and re-ablation was performed in 11(15.7%) patients. For group 2, 3(14.3%) patients needed reintervention. Re-ablation and re-ablation plus BNI were performed in 1(4.8%) and 2(9.5%), respectively. For group 3, cystoscopy was free in 1(4.3%), re-ablation and re-ablation plus BNI were performed 2(8.7%) and 1(4.3%), respectively. There were no significant differences in the re-admission and re-intervention rates among the three study groups (p=0.65 and p=0.50, respectively).

Conclusion:

In morphologically high bladder neck associated PUV, concomitant BNI with PVA doesn’t reduce early re-intervention rate.

Combined Angio-CT Systems: A Roadmap Tool for Precision Therapy in Interventional Oncology

Combined angiography-CT (angio-CT) systems, which combine traditional angiographic imaging with cross-sectional imaging, are a valuable tool for interventional radiology. Although cone-beam CT (CBCT) technology from flat-panel angiography systems has been established as an adjunct cross-sectional imaging tool during interventional procedures, the intrinsic advantages of angio-CT systems concerning superior soft-tissue imaging and contrast resolution, along with operational ease, have sparked renewed interest in their use in interventional oncology procedures. Owing to increases in affordability and usability due to an improved workflow, angio-CT systems have become a viable alternative to stand-alone flat-panel angiographic systems equipped with CBCT. This review aims to provide a comprehensive technical and clinical guide for the use of angio-CT systems in interventional oncology. The basic concepts related to the use of angio-CT systems, including concepts related to workflow setup, imaging characteristics, and acquisition parameters, will be discussed. Additionally, an overview on the clinical applications and the benefits of angio-CT systems in routine therapeutic and palliative interventional oncology procedures will be reviewed. Keywords: Ablation Techniques, CT-Angiography, Interventional-Body, Interventional-MSK, Chemoembolization, Embolization, Radiation Therapy/Oncology, Abdomen/GI, Skeletal-Axial Supplemental material is available for this article. © RSNA, 2021.

Diode Green Laser in the Lid Trichiasis Treatment

Purpose

To validate the standard values and evaluate the success rate in the treatment of minor and major trichiasis using thermoablation with a diode green laser.

Methods

In this interventional prospective study, individuals with minor or major trichiasis who were treated with thermoablation using diode green laser were included. The patients' mean age was 72.1 years; the majority were females (54.1%) and Caucasian (98%). The parameters of the diode laser were wavelength of 532 nm, application time of 200 ms, target size of 50 μm, interval between the shots 150 to 200 ms, and power of 600 to 750 mW. The number of shots was defined by the depth of ablation sufficient to reach the pilus hair bulb. The patients were evaluated by slit-lamp every 3 to 4 months, for up to 15 months. The treatment success rate and the association between variables were analyzed.

Results

The study sample was comprised of 98 patients with 135 affected lids and 337 lashes with trichiasis. Minor trichiasis (91.8%), unilateral trichiasis (67.3%), trichiasis affecting the lower eyelid (85.9%), and trichiasis resulting from blepharitis (64.3%) were the most common presentation profiles. The overall cure rate at the end of the study was 85%, with 69% being cured with a single session and 82.8% with two treatment sessions.

Conclusion

Thermoablation using a diode green laser applying the specified parameters to treat minor and major trichiasis is effective and results in high cure rate.

Cryoablation for Palliation of Painful Bone Metastases: The MOTION Multicenter Study

PURPOSE

To assess the clinical effectiveness of cryoablation for palliation of painful bone metastases.

MATERIALS AND METHODS

MOTION (Multicenter Study of Cryoablation for Palliation of Painful Bone Metastases) (ClinicalTrials.gov NCT02511678) was a multicenter, prospective, single-arm study of adults with metastatic bone disease who were not candidates for or had not benefited from standard therapy, that took place from February 2016 to March 2018. At baseline, participants rated their pain using the Brief Pain Inventory-Short Form (reference range from 0 to 10 points); those with moderate to severe pain, who had at least one metastatic candidate tumor for ablation, were included. The primary effectiveness endpoint was change in pain score from baseline to week 8. Participants were followed for 24 weeks after treatment. Statistical analyses included descriptive statistics and logistic regression to evaluate changes in pain score over the postprocedure follow-up period.

RESULTS

A total of 66 participants (mean age, 60.8 years ± 14.3 [standard deviation]; 35 [53.0%] men) were enrolled and received cryoablation; 65 completed follow-up. Mean change in pain score from baseline to week 8 was -2.61 points (95% CI: -3.45, -1.78). Mean pain scores improved by 2 points at week 1 and reached clinically meaningful levels (more than a 2-point decrease) after week 8; scores continued to improve throughout follow-up. Quality of life improved, opioid doses were stabilized, and functional status was maintained over 6 months. Serious adverse events occurred in three participants.

CONCLUSION

Cryoablation of metastatic bone tumors provided rapid and durable pain palliation, improved quality of life, and offered an alternative to opioids for pain control.Keywords: Ablation Techniques, Metastases, Pain Management, Radiation Therapy/OncologySupplemental material is available for this article.© RSNA, 2021.

Cryoablation and Immunotherapy for Breast Cancer: Overview and Rationale for Combined Therapy

Cryoablation is a well-tolerated outpatient procedure that has been used to treat metastatic sites as well as small breast cancers in patients who are considered poor candidates for surgery. Recent studies suggest that cell disruption caused by cryoablation may increase the expression and immunogenicity of tumor neoantigens, which could enhance the ability of the immune system to recognize and attack cancer cells at both local and distant sites. Such an approach might broaden the role of immunotherapy for the treatment of breast cancer, which has previously demonstrated limited response to these agents, likely owing to the modest immunogenicity of most breast cancer subtypes. If cryoablation can induce a systemic tumor-specific response, it could enhance tumor susceptibility to immunotherapy agents. This review briefly summarizes the necessary components for generating an immune response against tumor cells, reviews the tumor microenvironment of breast cancer, describes the rationale for and limitations of immune checkpoint inhibition, highlights the potential for cryoablation to induce a systemic tumor-specific immune response, and describes the rationale for combining cryoablation and immune checkpoint inhibitors for the treatment of breast cancer. Keywords: Ablation Techniques, Breast, Neoplasms-Primary, Percutaneous, Tumor Microenvironment, Tumor Response, Ultrasonography © RSNA, 2021.

Single-nodule hepatitis B virus-associated hepatocellular carcinoma smaller than 3 cm: two phenotypes defined by cluster analysis and their association with the outcome of ablation as the first-line therapy

OBJECTIVES

Hepatocellular carcinoma (HCC) is a heterogeneous disease. This study aimed to identify the heterogeneity related to the prognosis of ablation in patients with single-nodule hepatitis B virus (HBV)-associated HCC ≤3 cm.

METHODS

A total of 359 patients with single-nodule HBV-associated HCC ≤3 cm treated with curative thermal ablation were retrospectively investigated. Hierarchical cluster analysis was applied to obtain more homogeneous patient clusters concerning demographic and physiological characteristics. Discriminant analysis was performed to identify the relatively important variables for cluster analysis. Multiple correspondence analysis (MCA) was used to clarify the relationship between clusters and categorical variables. Overall survival (OS) was compared among clusters using the Kaplan-Meier model.

RESULTS

A two-cluster model was identified. Cluster 1 (n = 85) showed a higher percentage of female and older patients, higher inflammation response (higher prognostic nutritional index [PNI] and Glasgow prognostic score [GPS]), worse liver function (higher albumin-bilirubin grade and Child-Pugh grade), and relatively poorer immune status (higher neutrophil-to-lymphocyte ratio [NLR]) than cluster 2 (n = 274). NLR and GPS were the two most influential variables for cluster analysis (p < .0001). Cluster 2 had a significantly better prognosis than cluster 1. MCA revealed a clear negative correlation between inflammation status and liver function. Compared with cluster 1, the hazard ratios for OS of cluster 2 were 0.47 and 0.52 before and after adjusting for age, respectively (p < .05).

CONCLUSIONS

This study identified two sub-phenotypes of patients with single-nodule HBV-associated HCC ≤3 cm and their association with the outcome of thermal ablation alone as the first-line therapy. Key points Thermal ablation alone as the first-line therapy is not suitable for all patients with single-nodule hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) ≤3 cm. Patients with single-nodule HBV-associated HCC ≤3 cm can be identified as two sub-phenotypes associated with the outcome of thermal ablation alone as the first-line therapy, based on key preoperative clinical characteristics, especially inflammatory response and immune status. Patients with single-nodule HBV-associated HCC ≤3 cm characterized by late-onset disease, worse liver function, poorer immune status, and higher inflammatory response (with higher inflammatory response being the most important factor) are not suitable for thermal ablation alone as the first-line therapy. In contrast, patients with single-nodule HBV-associated HCC ≤3 cm characterized by early-onset disease, better liver function, lower inflammatory response, and good immune status (with lower inflammatory response being the most important factor) are particularly suitable for thermal ablation alone. Implications for patient care In the treatment of patients with single-nodule HBV-associated HCC ≤3 cm, thermal ablation alone as the first-line therapy should be carefully considered after recognizing the key clinical characteristics, among which inflammatory response and immune status are the two most important factors involved in clinical heterogeneity, and inflammatory response is closely related to the prognosis of thermal ablation alone as the first-line therapy for these patients.

Clinical Guideline for Microwave Ablation of Bone Tumors in Extremities

Microwave ablation has been used to treat bone tumors in extremities for more than 30 years. With improved recognition, updated microwave equipment, and expanded clinical application, microwave ablation has recently been widely used to treat bone tumors. To standardize the application of microwave ablation in the clinical treatment of bone tumors in the limbs, research results and clinical experience involving the use of microwave ablation to treat bone tumors in the limbs have been summarized, and a clinical guideline has been designed. This guideline is aimed at providing a reliable clinical basis for indications, preoperative evaluation and decision-making, perioperative treatment, complications, and other issues via evidence-based medicine. Two aspects are considered-percutaneous microwave ablation and intraoperative microwave ablation of bone tumors in extremities. Ultimately, the guideline is intended to standardize treatment and improve the clinical efficacy of microwave ablation of bone tumors in extremities.

Image-Guided Thermal Ablation for Colorectal Liver Metastases

Image-guided percutaneous thermal ablation is a widely acceptable local therapy for patients with colorectal liver metastases who are noneligible for surgery or present with recurrence after hepatectomy. The increasing knowledge of factors that affect oncologic outcomes has allowed selected patients with resectable small volume colorectal liver metastases to be treated by thermal ablation with curative intent. The continuous technological evolutions in imaging and image-guidance and the wide implementation of microwave ablation that overcomes most of the limitations of radiofrequency ablation have contributed to this paradigm shift. The importance of patient selection, ablation margin evaluation, and confirmation of complete tumor ablation (A0) are discussed in this article.

"How We Do It" - A Practical Approach to Percutaneous Adrenal Ablation Techniques

Incidental adrenal masses are common and are found in 4% of the CT scans.¹ While clinical history, laboratory results, and imaging characteristics are typically sufficient for diagnosis of an adrenal lesion, a biopsy is sometimes warranted. In some cases, adrenal mass ablation is subsequently indicated. This article serves as a brief but comprehensive review of preprocedural work-up and planning before an adrenal mass ablation, as well as a discussion on ablation techniques, associated challenges and solutions, and management of expected and unexpected outcomes.

Argon plasma coagulation tonsillectomy versus coblation tonsillectomy: a comparison of efficacy and safety

BACKGROUND

Tonsillectomy is one of the most common otolaryngological procedures. Nonetheless, there is still no universally approved 'gold standard' technique.

OBJECTIVE

To compare the safety and efficacy of argon plasma coagulation and coblation techniques in tonsillectomy.

METHODS

A multi-institutional, retrospective cohort study was conducted, comprising 283 patients who underwent bilateral tonsillectomies performed by a single surgeon between 2014 and 2017. The outcome measures included: operative time, intra-operative blood loss, post-operative pain and post-operative haemorrhage.

RESULTS

In the argon plasma coagulation group, mean operative time and post-operative haemorrhage rate were significantly reduced, p = 0.0006 and p = 0.003 respectively. There was no statistically significant difference between the two groups in terms of post-operative pain and intra-operative blood loss.

CONCLUSION

The argon plasma coagulation technique is easy, safe and efficacious. Argon plasma coagulation tonsillectomy seems cost-effective compared to coblation tonsillectomy: the single-use disposable electrode tip and wand used in this study cost AUD$76.50 and AUD$380 respectively. Argon plasma coagulation appears to be a favourable alternative to current modalities such as coblation.

Risk Assessment and Hydrodissection Technique for Radiofrequency Ablation of Thyroid Benign Nodules

Purpose: This retrospective study aimed to explore the importance of risk assessment and hydrodissection pre-treatment for radiofrequency ablation of thyroid nodules and initially establish the concept of thyroid nodule risk assessment and the corresponding ablation norms.

Method: Based on the specific location of thyroid nodules, risk assessment and the corresponding preventive measures for thyroid ablation were established. During the period of 2015.10-2017.5, a total of 382 patients were enrolled to compare the safety and efficacy of the ablation for patients with or without risk assessment and the corresponding preventive measures. Statistical analysis encompassed Independent T test for continuous variables and Fisher's exact test/Chi-square test for categorical variables.

Result: Of all 382 patients, 188 patients underwent ablation with risk assessment and the corresponding preventive measures before ablation and 194 without, respectively. The patient characteristics, risk grading, ablation time, thyroid function after ablation and the complete ablation rate showed no statistical differences exsisted between two groups (P>0.05). The complication in very high risk nodules was avoided in the group of patients with risk assessment and preventive measures before ablation.

Conclusion: It is a very safe and effective way to carry out radiofrequency ablation after pre-treatment of thyroid nodules by hydrodissection technique according to risk assessment. It will provide clinicians with greater help in the ablation treatment of thyroid nodules, and improve the safety of the thyroid ablation.

Irreversible Electroporation (IRE): Standardization of Terminology and Reporting Criteria for Analysis and Comparison

BACKGROUND

Irreversible electroporation (IRE) as newer ablation modality has been introduced and its clinical niche is under investigation. At present just one IRE system has been approved for clinical use and is currently commercially available (NanoKnife® system). In 2014, the International Working Group on Image-Guided Tumor Ablation updated the recommendation about standardization of terms and reporting criteria for image-guided tumor ablation. The IRE method is not covered in detail. But the non-thermal IRE method and the NanoKnife System differ fundamentally from established ablations techniques, especially thermal approaches, e.g. radio frequency ablation (RFA).

MATERIAL/METHODS

As numerous publications on IRE with varying terminology exist so far - with numbers continuously increasing - standardized terms and reporting criteria of IRE are needed urgently. The use of standardized terminology may then allow for a better inter-study comparison of the methodology applied as well as results achieved.

RESULTS

Thus, the main objective of this document is to supplement the updated recommendation for image-guided tumor ablation by outlining a standardized set of terminology for the IRE procedure with the NanoKnife Sytem as well as address essential clinical and technical informations that should be provided when reporting on IRE tumor ablation.

CONCLUSIONS

We emphasize that the usage of all above recommended reporting criteria and terms can make IRE ablation reports comparable and provide treatment transparency to assess the current value of IRE and provide further development.

Lone Atrial Fibrillation: Risk Factors, Triggers And Ablation Techniques

BACKGROUND

Since its introduction in 1953, lone atrial fibrillation (LAF) has not been defined with any consistency, resulting in an enormous variation in the way the term is used. Inherent to this, results from studies vary considerably. Many predisposing factors and pathogenic influences have been discovered over the past years, which raise the question if the term LAF should still be used and if the treatment should be different from non-lone atrial fibrillation (non-LAF). Therefore this systematic review on LAF provides an overview of risk factors and triggers, the second part focuses on the application of catheter and surgical ablation techniques.

METHODS

A systematic literature search was performed in the PubMed database. All identified articles were screened and checked for eligibility by the two authors. Additional literature was sought by screening the references of eligible articles.

CONCLUSIONS

Insufficient evidence exists to consider LAF as a real, isolated and useful entity. A re-definition or even avoiding the use of the term LAF might be appropriate.