Ablation Technique Research Articles

Modeling methods in overlapping electroporation treatments: Pulse number effects on tissue conductivity and ablation area

Irreversible electroporation (IRE) is a non-thermal tissue ablation technique that utilizes high-voltage pulses between electrode pairs to destroy tissue. Numerical models are essential for predicting treatment outcomes and aiding in treatment planning. This paper studies a nonlinear conductivity model (NC) and a multiparametric nonlinear conductivity model (MPNC) to investigate overlapping electroporation treatments using a three-needle electrode configuration. The NC model accounts for the effects of the electric field and temperature on tissue conductivity during multiple pulsed electric field applications. The MPNC model incorporates the influence of pulse number, alongside electric field and temperature, on tissue conductivity. Results indicate that in the MPNC model, tissue conductivity is significantly higher in regions where the electric field intensity is below the threshold for irreversible electroporation, with the maximum difference reaching 0.4S/m. In contrast, tissue conductivity is slightly lower in regions where the electric field intensity exceeds the IRE threshold. Additionally, the MPNC model predicts a smaller area of irreversible electroporation and a larger area of reversible electroporation, with these differences becoming more pronounced as the distance between electrode needles increases. These findings underscore the importance of considering pulse number effects in numerical models to enhance the accuracy of treatment planning for irreversible electroporation-based therapies.

Can Tumor Recurrence Be Predicted by Magnetic Resonance Imaging Findings Before Microwave Ablation in Patients with Hepatocellular Carcinoma?

Purpose: Hepatocellular carcinoma (HCC) is a common cancer. The primary treatment is surgery or liver transplantation. Percutaneous ablation techniques constitute the primary treatment in patients who are not suitable for surgery. Although it gives successful results, some studies report a recurrence rate of up to 50%. This study aimed to obtain an idea about the possibility of possible recurrence by evaluating the lesion characteristics in the pre-procedure MRI images of patients with and without recurrence. Methods: Forty-eight patients who underwent microwave ablation for HCC in our center between 2018 and 2021 were included in the study. Lesion size, presence of peripheral enhancement, arterial contrast enhancement, and T2 signal characteristics were evaluated on MRI. Subsequently, the relationship of these features with tumor recurrence was evaluated. Results: When lesions with and without recurrence were compared during follow-up, it was shown that the risk of recurrence was high in patients with lesion sizes larger than 3 cm and in lesions showing peripheral contrast enhancement (p 0.036 and p 0.021, respectively). Conclusion: Since there is a high probability of recurrence after ablation in HCCs larger than 3 cm and showing peripheral contrast, close follow-up will be beneficial.

Effect of wavelength and liquid on formation of Ag, Au, Ag/Au nanoparticles via picosecond laser ablation and SERS-based detection of DMMP.

The present study investigates the effects of input wavelength (1064, 532, and 355 nm) and surrounding liquid environment (distilled water and aqueous NaCl solution) on the picosecond laser ablation on silver (Ag), gold (Au), and Ag/Au alloy targets. The efficacy of the laser ablation technique was meticulously evaluated by analyzing the ablation rates, surface plasmon resonance peak positions, and particle size distributions of the obtained colloids. The nanoparticles (NPs) were characterized using the techniques of UV-visible absorption, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Furthermore, NPs of various sizes ranging from 6 to 35 nm were loaded onto a filter paper by a simple and effective drop-casting approach to achieve flexible surface-enhanced Raman spectroscopy (SERS) substrates/sensors. These substrates were tested using a simple, portable Raman device to identify various hazardous chemicals (malachite green, methyl salicylate, and thiram). The stability of the substrates was also systematically investigated by determining the decay percentages in the SERS signals over 60 days. The optimized SERS substrate was subsequently employed to detect chemical warfare agent (CWA) simulants such as methyl salicylate (a CWA simulant for sulfur mustard) and dimethyl methyl phosphonate (has some structural similarities to the G-series nerve agents) at different laser excitations (325, 532, and 633 nm). A notably higher SERS efficiency for CWA simulants was observed at a 325 nm Raman excitation. Our findings reveal that a higher ablation yield was observed at IR irradiation than those obtained at the other wavelengths. A size decrease of the NPs was noticed by changing the liquid environment to an electrolyte. These findings have significant implications for developing more efficient and stable SERS substrates for chemical detection applications.

Interventions for great saphenous vein insufficiency: A systematic review and network meta-analysis.

Great saphenous vein insufficiency (GSVI) adversely affects the quality of life of affected individuals. Minimally invasive endo-venous ablation techniques have emerged as effective and safe treatments, despite the longstanding use of surgical interventions. We aim in our study to evaluate all the available interventions in the literature, either endo-venous or conventional approaches for the treatment of GSVI. A thorough search was performed across four electronic databases to identify relevant studies. A frequentist network meta-analysis (NWM) was executed on the combined data to derive network estimates pertaining to the outcomes of concern. Risk ratios (RRs) were employed as the effect size metric for binary outcomes, while mean differences (MDs) were utilized for continuous outcomes, each reported with a 95% confidence interval. The qualitative review was conducted employing the Cochrane risk of bias assessment tool 1. Our NWM included 75 studies encompassing 12,196 patients. Regarding technical success rate within the first 5years after treatment, Endo-venous Laser Ablation (EVLA) with High Ligation and Stripping (HL/S), EVLA alone, Cyanoacrylate Adhesive Injection, cryostripping, HL/S and Radiofrequency Ablation (RFA) were significantly better than Ultrasound-Guided Foam Sclerotherapy and F-care. Also, invagination stripping was inferior to all interventions. Conservative Hemodynamic Cure for Venous Insufficiency and Varicose Veins (CHIVA) demonstrated a significantly lower recurrence rate with a RR of 0.35 [0.15; 0.79] compared to RFA, but RFA was more effective in recurrence prevention than HL/S and Mechanochemical Ablation (MOCA), with a RR of 0.63 [0.41; 0.97] and 0.18 [0.03; 0.95], respectively. Endo-venous Steam Ablation (EVSA) emerged as the most effective in reducing post-intervention pain, showing a MD of -2.73 [-3.72; -1.74] compared to HL/S. In Aberdeen Varicose Vein Questionnaire outcome, our analysis favored MOCA over most studied interventions, with an MD of -6.88 [-12.43; -1.32] compared to HL/S. Safety outcomes did not significantly differ among interventions. Our findings revealed significant variations in the technical success rates, recurrence rates, and post-intervention pain levels among different interventions. CHIVA exhibited enhanced performance in terms of lower recurrence rates, while EVSA emerged as a promising choice for mitigating post-intervention pain. Additionally, our analysis underscored the significance of patient-reported outcomes, with MOCA consistently yielding favorable results in terms of enhancing quality of life and expediting the return to regular activities.

Outcome after ablation of atypical atrial flutter: Is induction a feasible approach?

BackgroundAtypical atrial flutter (AAF) is an increasingly relevant clinical problem. Despite advancements in mapping and ablation techniques, the general management of these patients remain challenging especially when mapping cannot be performed during ongoing arrhythmia. There are no data whether induction of AAF is a feasible approach in these cases. MethodsWe retrospectively analyzed patients who underwent catheter ablation of AAF and compared procedural results between patients with ongoing tachycardia when starting the procedure and patients with induced AAF. ResultsWe analyzed 97 ablation procedures performed in 76 patients with a mean follow-up of 13.2 ± 12.2 months. In 68 procedures (70.1 %) AAF was ongoing at the beginning of the procedure and in 29 cases (29.9 %) AAF had to be induced.There was no statistically significant difference regarding acute procedural success. The recurrence rate of any arrhythmia during follow-up was significantly higher after ablation of ongoing AAF compared to induced AAF (63.2 % vs. 42.9 %; p = 0.047) driven by a significant higher rate of AAF-recurrence (57.4 % vs. 34.5 %; p = 0.039). The number of ablated tachycardias per patient as well as the number of de-novo tachycardias found during re-ablation showed no significant difference between both groups. ConclusionStarting a procedure with ongoing arrhythmia did not result in better short- or mid-term outcome in patients undergoing AAF ablation. Furthermore, based on our results inducing AAF seems a legitimate approach for AAF ablation in patients presenting in sinus rhythm.

Irreversible Electroporation has More Synergistic Effect with Anti‐PD‐1 Immunotherapy than Thermal Ablation or Cryoablation, in a Colorectal Cancer Model

AbstractBoosting the response rate of immune checkpoint blockade (ICB) therapy to improve treatment efficacy is a primary goal in cancer immunotherapy. One of the promising approaches involves focal tumor ablation to reduce tumor burden and trigger the in situ vaccination. Even though this combination strategy has demonstrated enhanced therapeutic outcomes in both preclinical research and clinical trials, limited research has comparatively investigated diverse ablation techniques. The optimal choice among focal therapy techniques remains largely unknown. In a murine colorectal cancer model (MC‐38), the therapeutic efficacy of anti‐PD‐1 in combination with thermal ablation, cryoablation, and irreversible electroporation (IRE) is evaluated, utilizing well‐characterized miniature probes. In this model, ICB monotherapy has limited effect in controlling tumor growth. IRE exhibits the most favorable synergistic effect with anti‐PD‐1 immunotherapy than thermal ablation or cryoablation, leading to the greatest primary tumor growth delay, longest tumor‐free survival, and highest protection against secondary tumor challenge. Furthermore, the co‐administration of IRE and anti‐PD‐1 significantly fosters the infiltration of CD8+ T cells into the tumor coupled with a remarkable stem‐like progenitor phenotype. The findings demonstrate that IRE stands as a promising modality that can potentiate the antitumor efficacy when the tumor is poorly responding to ICB monotherapy.

Study of Biological Effects Induced in Solid Tumors by Shortened-Duration Thermal Ablation Using High-Intensity Focused Ultrasound.

The HIFU ablation technique is limited by the long duration of the procedure, which results from the large difference between the size of the HIFU beam's focus and the tumor size. Ablation of large tumors requires treating them with a sequence of single HIFU beams, with a specific time interval in-between. The aim of this study was to evaluate the biological effects induced in a malignant solid tumor of the rat mammary gland, implanted in adult Wistar rats, during HIFU treatment according to a new ablation plan which allowed researchers to significantly shorten the duration of the procedure. We used a custom, automated, ultrasound imaging-guided HIFU ablation device. Tumors with a 1 mm thickness margin of healthy tissue were subjected to HIFU. Three days later, the animals were sacrificed, and the HIFU-treated tissues were harvested. The biological effects were studied, employing morphological, histological, immunohistochemical, and ultrastructural techniques. Massive cell death, hemorrhages, tissue loss, influx of immune cells, and induction of pro-inflammatory cytokines were observed in the HIFU-treated tumors. No damage to healthy tissues was observed in the area surrounding the safety margin. These results confirmed the efficacy of the proposed shortened duration of the HIFU ablation procedure and its potential for the treatment of solid tumors.

High sensitivity and ultra-low detection limit of violet phosphorus-based formaldehyde gas sensor by ultrasonic-assisted laser ablation

Formaldehyde (HCHO) pollution has emerged as a progressively critical environmental concern, with the detection of formaldehyde at trace levels being an indispensable requirement. Violet phosphorus (VP) nanoplates, recognized as innovative two-dimensional materials, are promising candidates for gas sensing due to their rich active sites and substantial specific surface area. This work pioneered the use of ultrasonic-assisted laser ablation in the synthesis of VP nanoplates. The as-produced VP nanoplates had the lateral dimension of 6.5 μm and the thickness of 2–6 nm (1–5 layers), which was strongly influenced by the ablation techniques employed and the processing parameters. The VP nanoplates demonstrated excellent sensitivity towards formaldehyde: gauge factor is 7.23 × 109; and resistance response is 144.6 % for detecting 20 ppb of formaldehyde. The detection limit is only 3 ppb. This work employed experiments and calculations to study the sensing mechanism. The binding energy between VP/G and HCHO is −1.276 eV, demonstrating the strong chemical adsorption. This paper provided a novel approach to fabricate VP nanoplates with superior formaldehyde sensitivity and ultra-low detection limitation, thereby showcasing significant potential for applications in detecting of air pollution.

Image-Guided Ablation for Cholangiocarcinoma: Current Evidence and Future Directions

AbstractThough the incidence of intrahepatic cholangiocarcinoma (ICC) is rare compared with other malignancies, its prevalence is increasing significantly worldwide. Intrahepatic cholangiocarcinoma is an aggressive tumor, typically presenting at an advanced stage and showing resistance to treatments. The primary cause of mortality is liver failure related to tumor progression with associated parenchymal loss and vascular or biliary compromise. Currently, surgical resection remains the primary curative approach, yet less than 20% of patients are eligible for such treatment, and postoperative rate of recurrence are high. In this context, locoregional therapies such as percutaneous thermal ablation have been shown to be safe and effective for patients with unresectable or recurrent ICCs. This review discusses the clinical application of ablation techniques, as it relates to patient selection and tumor characteristics for the treatment of ICC.

Intraoperative Ablation Control Based on Real-Time Necrosis Monitoring Feedback: Numerical Evaluation.

Ablation therapy is a type of minimally invasive treatment, utilized for various organs including the brain, heart, and kidneys. The accuracy of the ablation process is critically important to avoid both insufficient and excessive ablation, which may result in compromised efficacy or complications. The thermal ablation is formulated by two theoretical models: the heat transfer (HT) and necrosis formation (NF) models. In modern medical practices, feed-forward (FF) and temperature feedback (TFB) controls are primarily used as ablation control methodologies. FF involves pre-therapy procedure planning based on previous experiences and theoretical knowledge without monitoring the intraoperative tissue response, hence, it can't compensate for discrepancies in the assumed HT or NF models. These discrepancies can arise due to individual patient's tissue characteristic differences and specific environmental conditions. Conversely, TFB control is based on the intraoperative temperature profile. It estimates the resulting heat damage based on the monitored temperature distribution and assumed NF model. Therefore, TFB can make necessary adjustments even if there is an error in the assumed HT model. TFB is thus seen as a more robust control method against modeling errors in the HT model. Still, TFB is limited as it assumes a fixed NF model, irrespective of the patient or the ablation technique used. An ideal solution to these limitations would be to actively monitor heat damage to the tissue during the operation and utilize this data to control ablation. This strategy is defined as necrosis feedback (NFB) in this study. Such real-time necrosis monitoring modalities making NFB possible are emerging, however, there is an absence of a generalized study that discusses the integration and quantifies the significance of the real-time necrosis monitor techniques for ablation therapy. Such an investigation is expected to clarify the universal principles of how these techniques would improve ablation therapy. In this study, we examine the potential of NFB in suppressing errors associated with the NF model as NFB is theoretically capable of monitoring and suppressing the errors associated with the NF models in its closed control loop. We simulate and compare the performances of TFB and NFB with artificially generated modeling errors using the finite element method (FEM). The results show that NFB provides more accurate ablation control than TFB when NF-oriented errors are applied, indicating NFB's potential to improve the ablation control accuracy and highlighting the value of the ongoing research to make real-time necrosis monitoring a clinically viable option.

Narrative Review: Surgical and Hybrid Management of Atrial Fibrillation.

Although significant strides have been made in non-pharmacologic management of atrial fibrillation (AF), these treatments remain a work in progress. While catheter ablation is often effective for management of paroxysmal AF, it is less successful in patients with persistent or longstanding persistent AF. This review was undertaken to clarify the risks, benefits, and alternatives to catheter ablation for non-pharmacologic AF management. In order to clarify the roles of surgical and hybrid ablation, this narrative review was undertaken by searching MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, review articles, and other clinically relevant studies. The search was limited to English-language reports published between 1960 and 2023. Atrial fibrillation was searched using the terms surgical ablation, catheter ablation, hybrid ablation, stroke prevention, left atrial occlusion, and atrial excision. Google and Google Scholar, as well as bibliographies of identified articles, were also reviewed for additional references. The Cox-maze surgical approach is still the most efficacious non-pharmacological treatment for AF. Hybrid ablation, combining cardiac surgical and catheter ablation techniques, has become an attractive option for persistent or longstanding persistent AF.

Consensus of National Heart Center and the Saudi Arabian Cardiac Interventional Society on the Current Landscape of the Management of Intracoronary Calcification in Saudi Arabia.

We aimed to develop a streamlined algorithm for the management of intracoronary calcification that includes guidance on intracoronary imaging and the appropriate selection of atherectomy devices. National experts representing both the National Heart Center (NHC) and the Saudi Arabian Cardiac Interventional Society (SACIS) met to develop a consensus document on the assessment and management of intracoronary calcification in Saudi Arabia. The nominal group technique was utilized; a number of statements on the assessment and management of coronary artery calcification were developed based on a systematic review of the literature. The authors discussed the developed statements until a consensus was reached. Twenty statements were discussed and agreed upon. Invasive and non-invasive imaging modalities in the assessment of coronary artery calcification, and management of intracoronary calcification using calcium ablation techniques, excimer laser coronary atherectomy, ballon-based techniques, and shockwave lithotripsy; were all thoroughly discussed in light of scientific evidence and the experts' clinical practice. We present a national consensus on the assessment and the multifaceted management of intracoronary calcification in Saudi Arabia.

Nanosecond pulse electric field treatment initiates mitochondrial apoptosis pathway by inducing mitochondrial morphological changes in myocardial cells.

As an emerging myocardial ablation technique, the mechanism of nanosecond pulse electric field (nsPEF) ablation is currently less studied. Mitochondria are one of the important membrane structure organelles in cells, participating in numerous life activities within the cell. This study aimed to explore the morphological changes of mitochondria in living cells following nsPEF treatment. Myocardial cells were treated with a self-made solid-state LTD high-voltage nanosecond pulse generator with a pulse width of 100ns for 80 times. The changes in mitochondrial membrane potential and cell apoptosis in rat myocardial cells after nsPEFs were investigated using JC-1 assay kit, apoptosis double staining assay kit, and mitochondrial fluorescence probe. The results showed that after nsPEF treatment, the mitochondrial membrane potential decreased, apoptosis increased, and the average mitochondrial area decreased from 0.48 µm2 in live myocardial cells to 0.16 µm2. The average circumference ranges from 3.17µm dropped to 1.60µm. The shape factor decreased from 1.92 to 1.41. The aspect ratio has decreased from 2.16 to 1.59. nsPEF treatment induces changes in the morphology of myocardial cell mitochondria. Based on the results of mitochondrial membrane potential and apoptosis, it can be inferred that under this equipment and parameter conditions, nsPEF treatment first causes changes in mitochondrial morphology, and then initiates the mitochondrial apoptosis pathway, which may provide experimental basis for investigating the potential mechanism of nsPEF ablation of myocardial cells.

Registro español de ablación con catéter. XXIII informe oficial de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (2023)

Introduction and objectivesWe report the results of the 2023 Spanish catheter ablation registry. MethodsProcedural data were collected and incorporated into the REDCap platform by all participating centers through a specific form. ResultsThere were 104 participating centers in 2023 compared with 103 in 2022. In 2023, the total number of ablation procedures was 26 207, indicating a stabilization of the increase observed in 2022 following the pandemic. The increase was mainly due to procedures for atrial fibrillation (AF), with a total of 9942 ablations, representing 38% of all substrates. Notably, pulse-field ablation represented 10.3% of all AF ablation procedures, leading single-shot ablation strategies to outnumber point-by-point AF ablation for the first time in the history of the registry. Cavotricuspid isthmus ablation remained the second most targeted substrate (19% of all substrates, n=5067). The overall acute success rate remained high (97%), with a downward trend in the complication rate (1.6% vs 1.8% in 2022) and mortality rate (0.03%; n=7). Compared with 2022, there was a significant increase in procedures performed using electro-anatomical mapping and zero-fluoroscopy techniques for cavotricuspid isthmus ablation (52% vs 26%), AV node re-entrant tachycardia (48% vs 34%), and accessory pathways (62% vs 22%). We registered 466 ablations in pediatric patients. ConclusionsThe data indicate a stabilization in the post-pandemic increase in ablation procedures, with an absolute and relative increase in AF as the predominant substrate. Success rates remained stable with a modest reduction in complication and mortality rates.

Comparative analysis of VenaBlock and VenaSeal Systems for catheter-guided endovenous cyanoacrylate closure in treating chronic venous insufficiency of the lower extremity: effectiveness and feasibility.

Cyanoacrylate adhesive closure (CAC) systems are widely used to treat varicose veins. In terms of efficacy and safety, these nonthermal, non-tumescent methods are noninferior to endovenous thermal ablation techniques. However, no published studies have compared products that use CAC systems. VenaSeal® (Medtronic, Santa Rosa, CA, USA) and VenaBlock® (Invamed) are the most commonly used CAC-based products worldwide. This study aimed to focus on the efficacy of these two commonly used products, with little emphasis on safety. Published full-text articles on the VenaBlock® and VenaSeal® systems were searched. Data for each product were evaluated by comparing them with each other in terms of effectiveness. In total, 1882 extremities from 11 studies using VenaBlock® and 524 extremities from eight studies using VenaSeal® were included and compared. Both devices were effective, and their cumulative recanalization-free survival rates were similar (P=0.188) at the 6-, 12-, 24-, 36-, and 60-month follow-ups. Both products improved the venous clinical severity score (VCSS) and quality of life (QoL) scores. VenaBlock® and VenaSeal® are effective in terms of cumulative recanalization-free survival rates, and no significant difference was found between the two groups (P=0.188). Both significantly improve the VCSS and QoL scores. CAC is feasible for the treatment of varicose veins.

Image-guided peripheral nerve interventions- applications and techniques

Interventional radiology continues to be at the forefront of acute and chronic pain management. Our unique imaging expertise and ability to target difficult to reach structures allows for the continuous development of new ways to treat a variety of pain generators. In addition, the advent of thermal ablation techniques and technologies has provided a unique opportunity to offer patients more durable and predictable options to treat their pain. This is particularly important during the opioid epidemic, as multiple local and international governmental bodies push for physicians to create ways to manage pain while reducing the need for long-term opioid dependence. This article aims to review various image-guided techniques and tools for the treatment of pain related to peripheral pain generators, with a focus on the extremities, lumbosacral and pelvic region, and the chest wall. For each target and pathology, we will discuss general etiology, anatomy, procedural approach, and briefly evaluate the supporting literature in each clinical situation.

Cardiac Arrhythmias and Their Management: An In-Depth Review of Current Practices and Emerging Therapies.

Cardiac arrhythmias encompass a range of conditions characterized by abnormal heart rhythms, affecting millions globally and significantly contributing to morbidity and mortality. This review provides a comprehensive analysis of the current practices and emerging therapies in managing cardiac arrhythmias, covering their definition, classification, epidemiology, and the critical importance of effective management. It explores the pathophysiology underlying various arrhythmias, including the mechanisms of arrhythmogenesis, such as re-entry, automaticity, and triggered activity. The review details the latest diagnostic tools, including ECG, Holter monitoring, and electrophysiological studies, and discusses the clinical presentation of different arrhythmias, from supraventricular to ventricular types and bradyarrhythmias. We examine current pharmacological and non-pharmacological treatment strategies, such as antiarrhythmic drugs, catheter ablation, and device therapy, highlighting their efficacy and limitations. Furthermore, the review delves into emerging therapies, including advanced catheter ablation techniques, novel antiarrhythmic agents, gene therapy, and innovative device technologies like leadless pacemakers and subcutaneous implantable cardioverter-defibrillators (ICDs). Special considerations for managing arrhythmias in diverse populations, including pediatrics, the elderly, and pregnant women, are discussed. Additionally, the review explores future directions in arrhythmia management, emphasizing personalized medicine, artificial intelligence applications, and the integration of advanced technologies in diagnosis and treatment. By synthesizing current knowledge and prospects, this review aims to enhance understanding and promote advancements in the field, ultimately improving patient outcomes with cardiac arrhythmias.

Detection of gentamicin in water and milk using chitosan-ZnS-Au nanocomposite based on surface plasmon resonance imaging sensor

The detection of antibiotics in milk, water, and agricultural products is a topic of interest for health care and environmental protection. Some antibiotics such as oxytetracycline and gentamicin are the prominent contaminants in water and milk. In this study, the chitosan-ZnS and chitosan-ZnS-Au nanocomposites were fabricated using a laser ablation technique. The nanocomposites were covered on the glass substrate as a layer sensor characterized by analytical methods. Consequently, the thickness of layers was in the range of 36.3 to 38.21 nm. The surface plasmon resonance image patterns demonstrated the interaction of the gentamicin and oxytetracycline with nanocomposites. As a result, the sensor is sensitive to detect gentamicin, and the limit of detection, the affinity constant, and response time were about 0.1 ppm, 102.04 a.u., and 268 s respectively.

Thermoablation Using Radiofrequency and Microwaves of Autonomous Thyroid Nodules: Our Experience

Significant results have been achieved using ultrasound-guided and ultrasound-assisted ablative techniques, such as Laser Thermal Ablation (LTA), Radiofrequency Ablation (RFA), High-Intensity Focused Ultrasound (HIFU), and Microwave Ablation (MWA). These techniques are ideally suited for the treatment of normally functioning benign thyroid nodes with local compressive symptoms or aesthetic problems. These treatments have been applied to hyperfunctioning “hot” nodes. LTA and RFA are the most commonly used. From January 2021 to July 2023 at our Center, a total of 160 patients with benign thyroid nodules were treated, of which 35 had autonomous nodules [1-4]. Our analysis focused on evaluating the locoregional treatment of the latter. Based on the volume and ultrasound-vascular characteristics, patients were selected for thermoablative treatment with either RFA or MWA (Amica Gen HS - Hospital Service) starting in July 2022. No complications were documented. However, one patient was referred for surgery and 1 patient was re-treated with MWA. In the light of personal experience ultrasound-guided thermal ablation treatment with RFA in patients with a single pretoxic or toxic thyroid nodule with or without associated compressive or aesthetic symptoms has proven to be very effective and satisfactory. The treatment must be preceded by adequate information regarding the advantages and disadvantages of the various procedures and the methods of the treatment session. MWA proved to be more effective than RFA with no functional recovery of the treated nodules even if they were relatively larger in size. We obtained the suspension of thyrostatic therapy with normalization of the TSH level in the third month after treatment.

Radiation therapy and IRreversible electroporation for intermediate risk prostate cancer (RTIRE)

IntroductionRadiation Therapy and IRreversible Electroporation for Intermediate Risk Prostate Cancer (RTIRE) is a phase II clinical trial testing combination of radiation therapy and irreversible electroporation for intermediate risk prostate cancerBackgroundPCa is the most common non-cutaneous cancer in men and the second leading cause of cancer death in men. PCa treatment is associated with long term side effects including urinary, sexual, and bowel dysfunction. Management of PCa is based on risk stratification to prevent its overtreatment and associated treatment-related toxicity. There is increasing interest in novel treatment strategies, such as focal therapy, to minimize treatment associated morbidity. Focal therapy alone has yet to be included in mainstream guidelines, given ongoing concerns with potentially higher risk of recurrence. We hypothesize combining focal therapy with whole gland, reduced dose radiotherapy will provide acceptable oncologic efficacy with minimal treatment associated morbidity. RTIRE is a phase II single institution, investigator-initiated study combining a local ablative technique though local irreversible electroporation (IRE) with MR guided RT (MRgRT) to treat the entire prostate. The goal is to provide excellent oncologic outcomes and minimize treatment related side effects through leveraging benefits of locally ablative therapy with established radiation treatment techniques.MethodsA total of 42 men with intermediate risk PCa per NCCN guidelines and focal grade group (GG) 2 or 3, Gleason Score (GS) 3 + 4 or GS 4 + 3, cancer in an MRI target will be enrolled. Patients with MRI visible foci of GG2/GG3 will undergo focal therapy with IRE of this lesion. Following successful focal therapy, patients will then undergo a course of reduced dose, whole gland MRgRT with either 32.5 Gy in 5 Fractions or 22 Gy in 2 fractions. The primary objective of the study is to determine safety. Secondary outcomes include evaluation of oncologic efficacy (as measured by the proportion of patients free of clinically significant cancer as defined as > Grade Group 1 at 1-year follow-up biopsy), imaging characteristics of patients pre and post RTIRE, impact on quality of life (QoL), and PSA kinetics.DiscussionCombining IRE with a reduced dose radiotherapy may offer a new treatment paradigm for PCa by both reducing treatment effects of full dose radiotherapy and minimizing the risk of recurrence observed with focal therapy.Trial RegistrationClinicaltrials.gov identifier: NCT05345444. Date of registration: April 25, 2022. Protocol Version: 6.0, July 7, 2023.