Thermoablative Techniques Research Articles

Exploring the Efficacy of Combining Radiofrequency Thermal Ablation or Microwave Ablation with Vertebroplasty for Pain Control and Disease Management in Metastatic Bone Disease-A Systematic Review.

Interventional radiology techniques have become pivotal in recent years in managing metastatic bone disease, which frequently results in skeletal complications such as fractures and severe pain. Thermoablative methods like radiofrequency ablation (RFA) and microwave ablation (MWA), when combined with vertebroplasty (VP), are proving increasingly beneficial for these patients. The search was independently conducted by two radiologists on MEDLINE databases, using specified strings up to April 2024. Methodological quality was assessed using PRISMA guidelines. Studies meeting inclusion criteria investigated thermoablation techniques (RFA and/or MWA) combined with VP, focusing on pain management and disease control outcomes in adults. Among 147 results, 42 articles met the criteria, with varied prospective and retrospective designs and sample sizes averaging 49 patients, predominantly involving RFA (30 studies), MWA (11 studies), and one comparative study. Our review highlights significant pain reduction, effective local tumor control, and favorable safety of combined RFA or MWA with VP, supporting its potential in managing vertebral pathologies and warranting further clinical integration. The combined treatment of RFA/MWA with VP demonstrates significant pain reduction and local tumor control, with a rapid onset of analgesic effect. These findings support its crucial role in clinical practice for managing vertebral metastases.

10 Cases of Nonresponse to Laser Thermoablation from a Series of 187 Patients: Histological Outcomes after Surgery and Related Evaluations.

Thyroid thermoablative techniques have been developed as an alternative to surgery for the treatment of symptomatic benign nodes, with the advantage of being minimally invasive, repeatable, with a minimal complication rate, and avoiding the perioperative risks and irreversible consequences of surgery. A series of patients undergoing laser thermoablation by the same team of endocrinologists operating in 2 centers from May 2016 to December 2022 is presented. The procedure was performed in patients with compressive symptomatology determined by a thyroid node typed TIR 2, or TIR 3A with rejection of the surgical option. We analyzed cases that required surgery because of persistent compressive symptoms, reduction failure, or increase in volume. From May 2016 to December 2022, 207 thermoablative procedures were performed (187 patients). Single ablative session was unresolved in 28 patients (15%). The proportion of nodes with TIR 3A cytology was significantly higher (21.4 vs 7.0%). In this group, the response in terms of volumetric reduction 6 months after the procedure was significantly lower (5.7% vs 50%). Ten patients (5.3%) underwent surgery, whose histological outcome demonstrated malignancy in 50% of cases. Data show the importance of timely re-evaluation with referral to surgical treatment for patients presenting a less than 20% volume reduction 6 months after thermoablation, in order to ensure promptly effective treatment of misrecognized malignancies.

Analytical solutions in the modeling of the endovenous laser ablation

We modeled the operative treatment of incompetent truncal veins using endovenous laser ablation (EVLA). The main concern regarding the thermoablative technique is tissue damage, which is correlated with (1) the energy provided by the laser power and (2) temperature distribution. Our objective was to accurate the two functions, namely the fluence rate and the temperature, depending on the thermoablative technique and the endovenous laser treatment (ELT). First, we considered three differential equations: diffusion, heat, and bioheat equations in the endovenous-perivenous multidomain to describe the lumen, the vein wall, the tissue pad, and the skin. Second, we examined the power source according to the Beer-Lambert law in the incident beam irradiance and the heat source as the so-called absorbed optical power density. Third, we checked out the heat transfer at the skin boundary according to Newton’s law of cooling, which stands for a Robin boundary condition. For this new model, we proposed exact solutions: applying differential equations techniques, we solved (1) a diffusion approximation of the radiative transfer equation under the considered power source, and (2) the coupled heat and bioheat equations under the considered heat source accomplished with the Robin boundary condition. Then, we graphically illustrated the fluence rate profile and discussed its time dependence and steady state. Besides, we discuss thermal damage to the vein-tissue system and present open problems.

Interventional oncological treatment of breast cancer liver metastasis (BCLM): single center long-term evaluation over 26 years using thermoablation techniques like LITT, MWA and TACE in a multimodal application

The purpose of the study is to retrospectively evaluate the development and technological progress in local oncological treatments of patients with breast cancer liver metastasis (BCLM) using LITT (laser interstitial thermotherapy), MWA (microwave ablation) and TACE (transarterial chemoembolization) ablation techniques in a multimodal application. The study uses data generated between 1993 and 2020. Therapy results were evaluated using the Kaplan–Meier survival estimate, Cox proportional hazard regression and log-rank test. Cox regression analysis showed that the different treatment methods are statistically significant predictors of survival of patients. Median survival times for groups treated with LITT (212 patients) and LITT + TACE (215 patients) were 2.2 years and 2.1 years respectively; median survival times for groups treated with MWA (17 patients) and MWA + TACE (143 patients) were 5.6 and 2.4 years respectively. For LITT only treatments, the 1-, 3- and 5-year survival probability scored 80%, 37%, 22%. Results for combined LITT + TACE treatments were 76%, 34% and 15%. In group MWA, the 1-/3-/5-year survival probability rates were calculated as 89%, 89%, 89% (however, they should be interpreted carefully due to a relatively small sample size of n = 17 patients). Group MWA + TACE offered values of 77%, 38% and 22%. A separate group of 549 patients was analyzed with TACE monotherapy treatment. The estimated median survival time in this group was 0.8 years. The 1-/3-/5-year survival probability rates were 37%, 8% and 4%. Treatments with combined MWA and MWA + TACE resulted in the best median survival time estimations in this study.

Interventional oncological treatment of hepatocellular carcinoma (HCC) - A single-center long-term evaluation of thermoablation techniques like LITT, MWA, and TACE in a multimodal application over 26 years

PurposeThe purpose of the study is to retrospectively evaluate the development and technological progress in local oncological treatments of hepatocellular carcinoma (HCC) by means of ablation techniques like laser interstitial thermal therapy (LITT), microwave ablation (MWA) and transarterial chemoembolization (TACE) in a multimodal application.MethodThis retrospective single-center study uses data generated between 1993 and 2020 (1,045 patients). Therapy results are evaluated using survival rates of Kaplan-Meier estimator, Cox proportional hazard regression and log-rank test.ResultsMedian survival times in group LITT (25 patients) are 1.6 years, and, 2.6 years for LITT + TACE (67 patients). For LITT only treatments 1-/3-/5-year survival rates scored 64%, 24% and 20%. Results for combined LITT + TACE treatments were 84%, 37% and 14%. Median survival time in group MWA (227 patients) is 4.5 years. Estimated median survival time for MWA + TACE (108 patients) leads to a median survival time of 2.7 years. In group MWA the 1-/3-/5-year survival rates are 85%, 54%, 45%. Group MWA + TACE shows values of 79%, 41% and 25%. A separate group of 618 patients has been analyzed with TACE as monotherapy. Median survival time of 1 year was estimated in this group. 1-/3-/5-year survival rates are 48%, 15% and 8%. - Cox regression analysis showed that the different treatment methods are statistically significant predictors for survival of patients.ConclusionsTreatments with MWA resulted in best median survival rates, followed by MWA + TACE in combination. Survival rates of MWA only are significantly higher vs. LITT, vs. LITT + TACE and vs. TACE monotherapy.

Spray coagulation as an alternative to argon plasma coagulation for bleeding portal hypertensive gastropathy

Spray coagulation as an alternative to argon plasma coagulation for bleeding portal hypertensive gastropathy

Radiofrequency and laser to treat varicose veins: Comparison of postoperative pain in current practice

Varicose veins of the lower limbs are more and more treated by radiofrequency or laser thermoablation techniques. Several studies compared the effectiveness of these two techniques but data comparing immediate per and post-operative outcomes are limited. Primary outcome of this study was to compare per- and immediate postoperative pain of patients treated with laser or radiofrequency.

Management of Osteoblastoma and Giant Osteoid Osteoma with Percutaneous Thermoablation Techniques.

Osteoblastoma (OB) is a rare, benign bone tumor, accounting for 1% of all primary bone tumors, which occurs usually in childhood and adolescence. OB is histologically and clinically similar to osteoid osteoma (OO), but it differs in size. It is biologically more aggressive and can infiltrate extraskeletal tissues. Therapy is required because of severe bone pain worsening at night. Moreover, non-steroid anti-inflammatory drugs (NSAIDs) are not a reasonable long-term treatment option in young patients. Surgical excision, considered the gold standard in the past, is no longer attractive today due to its invasiveness and the difficulty in performing a complete resection. The treatment of choice is currently represented by percutaneous thermoablation techniques. Among these, Radiofrequency ablation (RFA) is considered the gold standard treatment, even when the lesions are located in the spine. RFA is a widely available technique that has shown high efficacy and low complication rates in many studies. Other percutaneous thermoablation techniques have been used for the treatment of OB, including Cryoablation (CA) and laser-ablation (LA) with high success rates and low complications. Nevertheless, their role is limited, and further studies are necessary.

Percutaneous management of bone metastases: State of the art

Interventional radiology is playing an increasingly important role in the local treatment of bone metastases; this treatment is usually done with palliative intent, although in selected patients it can be done with curative intent. Two main groups of techniques are available.The first group, centered on bone consolidation, includes osteoplasty/vertebroplasty, in which polymethyl methacrylate (PMMA) is injected to reinforce the bone and relieve pain, and percutaneous osteosynthesis, in which fractures with nondisplaced or minimally bone fragments are fixed in place with screws. The second group centers on tumor ablation. tumor ablation refers to the destruction of tumor tissue by the instillation of alcohol or by other means. Thermoablation is the preferred technique in musculoskeletal tumors because it allows for greater control of ablation. Thermoablation can be done with radiofrequency, in which the application of a high frequency (450 Hz–600 Hz) alternating wave to the tumor-bone interface achieves high temperatures, resulting in coagulative necrosis. Another thermoablation technique uses microwaves, applying electromagnetic waves in an approximate range of 900 MHz–2450 MHz through an antenna that is placed directly in the core of the tumor, stimulating the movement of molecules to generate heat and thus resulting in coagulative necrosis. Cryoablation destroys tumor tissue by applying extreme cold. A more recent, noninvasive technique, magnetic resonance-guided focused ultrasound surgery (MRgFUS), focuses an ultrasound beam from a transducer placed on the patient's skin on the target lesion, where the waves’ mechanical energy is converted into thermal energy (65 °C–85 °C). Treatment should be planned by a multidisciplinary team. Treatment can be done with curative or palliative intent. Once the patient is selected, a preprocedural workup should be done to determine the most appropriate technique based on a series of factors. During the procedure, protective measures must be taken and the patient must be closely monitored. After the procedure, patients must be followed up.

Manejo percutáneo de las metástasis óseas

Interventional radiology is playing an increasingly important role in the local treatment of bone metastases; this treatment is usually done with palliative intent, although in selected patients it can be done with curative intent. Two main groups of techniques are available.The first group, centered on bone consolidation, includes osteoplasty / vertebroplasty, in which polymethyl methacrylate (PMMA) is injected to reinforce the bone and relieve pain, and percutaneous osteosynthesis, in which fractures with nondisplaced or minimally bone fragments are fixed in place with screws. The second group centers on tumor ablation. Tumor ablation refers to the destruction of tumor tissue by the instillation of alcohol or by other means. Thermoablation is the preferred technique in musculoskeletal tumors because it allows for greater control of ablation. Thermoablation can be done with radiofrequency, in which the application of a high frequency (450 Hz–600Hz) alternating wave to the tumor-bone interface achieves high temperatures, resulting in coagulative necrosis. Another thermoablation technique uses microwaves, applying electromagnetic waves in an approximate range of 900MHz to 2450MHz through an antenna that is placed directly in the core of the tumor, stimulating the movement of molecules to generate heat and thus resulting in coagulative necrosis. Cryoablation destroys tumor tissue by applying extreme cold. A more recent, noninvasive technique, magnetic resonance-guided focused ultrasound surgery (MRgFUS), focuses an ultrasound beam from a transducer placed on the patient's skin on the target lesion, where the waves’ mechanical energy is converted into thermal energy (65°C–85°C). Treatment should be planned by a multidisciplinary team. Treatment can be done with curative or palliative intent. Once the patient is selected, a preprocedural workup should be done to determine the most appropriate technique based on a series of factors. During the procedure, protective measures must be taken and the patient must be closely monitored. After the procedure, patients must be followed up.

The current state and future perspectives of high intensity focused ultrasound (HIFU) ablation for benign thyroid nodules.

High intensity focused ultrasound (HIFU) is a new thermoablation technique used to treat benign thyroid nodules. In this method, the ultrasound beam passes through the patient's skin and focuses very precisely on the target lesion at a distance far from the source of ultrasound generation, making HIFU the only truly non-invasive method of thermoablation developed to date. HIFU is therefore an attractive alternative to surgery and other thermoablative techniques. This review describes the principles of HIFU treatment, the selection of patients suitable for HIFU, the course and effects of treatment, and future perspectives.

MR-Guided Focused Ultrasound in Fibroid Treatment - Results of the 4th Radiological-Gynecological Expert Meeting.

Magnetic Resonance-guided focused ultrasound (MRgFUS; Syn.: HIFU = high intensity focused ultrasound) is a safe and effective thermoablative technique to treat fibroid-related symptoms. The evidence is limited due to a lack of randomized trials. The indication for treatment by MRgFUS are symptomatic uterine fibroids. This consensus paper covers criteria to measure success, contraindications, side effects and complications of MRgFUS treatment. The role of MRgFUS in the setting of family planning is part of this publication.

Magnetic resonance-guided focused ultrasound thalamotomy for treatment of essential tremor: A 2-year outcome study.

Magnetic resonance-guided focused ultrasound is an emerging, minimally invasive thermoablation technique for medically refractory essential tremor. Beyond the initial year, data regarding efficacy and potential predictors of efficacy are still preliminary. The objective of this study was to assess the outcome at 2 years and the association between lesion volume and outcome 1 year after treatment. We reviewed data from 37 patients who underwent unilateral magnetic resonance-guided focused ultrasound thalamotomy, with primary outcome being dominant tremor subscore of the Clinical Rating Scale for Tremor. We used multivariable linear regression to model initial lesion volume with 1-year outcome, adjusting for other clinically relevant variables. Although we detected a trend in loss of clinical benefit within the first year, the dominant tremor score at 2 years continued to be significantly improved (43.4%, 95% confidence interval 27.8%-59.0%) from baseline. Secondarily, initial lesion volume is significantly associated with 1-year outcome. Our findings show that magnetic resonance-guided focused ultrasound thalamotomy results in sustained tremor reduction for medically refractory essential tremor even in the long term, and we highlight areas for improvement.

Feasibility of bipolar radiofrequency ablation in patients with parathyroid adenoma: a first evaluation

Aim: The aim of this study was to first assess the feasibility of bipolar radiofrequency ablation in patients with parathyroid adenoma.Material and methods: Bipolar RFA was performed in 9 patients with primary parathyroid adenoma in one single session. Measured parameters were PTH and calcium serum levels prior to and after bRFA. Furthermore, using an NRS pain scale (1–10), the individual, subjective maximum sensation of pain was documented.Results: The bRFA resulted in a highly significant (p = .003906) decrease of serum PTH levels (median 67 ng/l) in comparison to those prior to the intervention (median 199 ng/l). Regarding calcium levels, there was no statistical significance (p = .460938), with a decrease of median serum levels comparing pre- and post-bRFA values from 2.82 mmol/l to 2.66 mmol/l. The evaluation of the individual pain sensation during the procedure was assessed by the patients with a median of 5/10 on the NRS scale. In none of the 9 cases complications such as infections, persisting pain or nerve injury occurred.Conclusion: For the first time, it was possible to depict the successful therapy of parathyroid adenoma by means of bRFA. This work thus proves bRFA to be an effective, safe, applicable and, concerning sensation of pain, very well tolerable thermoablative technique in the treatment of parathyroid adenoma.

MR-Guided Focused Ultrasound in Fibroid Treatment - Results of the 3rd Radiological-Gynecological Expert Meeting.

Magnetic Resonance-guided focused ultrasound (MRgFUS; Syn.: HIFU = high intensity focused ultrasound) is a safe and effective thermoablative technique to treat fibroid-related symptoms. The evidence is limited due to a lack of randomized trials. The indication for treatment by MRgFUS are symptomatic uterine fibroids. This consensus paper covers criteria to measure success, contraindications, side effects and complications of MRgFUS treatment. The role of MRgFUS in the setting of family planning is part of this publication.

Radiofrequency Ablation for Treatment of Refractory Gastric Antral Vascular Ectasia: A Systematic Review of the Literature.

Background and Study Aims GAVE is an uncommon cause of upper nonvariceal bleeding and often manifests itself as occult bleeding with chronic anemia. To date, the standard of care for GAVE is endoscopic treatment with thermoablative techniques. Despite good technical results, approximately two thirds of patients remain dependent on transfusions after the therapy. One of the emerging and more promising endoscopic treatments for GAVE is radiofrequency ablation (RFA). The aim of this study is to perform a systematic review of literature in order to assess current evidence supporting the effectiveness of this technique for treatment of refractory GAVE. Materials and Methods Through electronic search, we identified 14 records, and after removal of duplicates and irrelevant studies, we selected 10 studies on radiofrequency ablation of GAVE: 4 prospective open-label single-center studies, 1 retrospective multicentric study, and 5 case reports. Results Among all 72 treated patients reported in literature, 74.3% achieved a clinical response, while nonfatal AEs have been reported in 4.2% of cases. Conclusions Despite some qualitative limitations, all literature data support effectiveness of RFA for treatment of refractory GAVE. In the future, large prospective controlled trials with adequate follow-up are needed to better assess the effectiveness and safety of this procedure.

Thermoablation therapy in the treatment of benign lesions

Depending on their size and location, some benign tumors can cause prolonged discomfort and even rupture and fatal bleeding in severe cases. Hitherto the therapeutic strategies for such lesions were observation, surgery and in selected cases transarterial embolization. Our aim was to present the possibilities of thermoablation for treating lesions. Here we present interventions of four patients in Semmelweis University Department of Transplantation and Surgery. A thyroid adenoma and a kidney angiomyolipoma were treated with radiofrequency ablation. Two patients with a liver haemangioma were treated with microwave thermoablation technique. Complications were not observed in any of the cases. In most cases, the size of the treated lesions decreased. The mean decrease in volume was 32.7%. The contrast enhancement of the lesions also decreased, the mean reduction in contrast enhancing volume was 75.3%. Thermoablational procedures for the benign tumors presented above are safe. The therapy shows excellent cosmetic results, a shorter hospital stay and quicker recovery. Orv. Hetil., 2016, 157(51), 2040-2047.

Bipolar radiofrequency ablation of benign thyroid nodules using a multiple overlapping shot technique in a 3-month follow-up

Purpose The aim of this study was to evaluate the decrease of benign thyroid nodules after bipolar radiofrequency ablation (RFA) in a 3-month follow-up using a multiple overlapping shot technique (‘MOST’).Methods A total of 18 patients with 20 symptomatic benign thyroid nodules (17 cold nodules, 3 hyperfunctioning nodules) were treated in one single session by bipolar RFA. Bipolar ablation was performed using MOST. The nodule volumes were measured prior to ablation and 3 months after the procedure using ultrasound. The population consisted of either solid (>80% solid tissue within the volume of interest), complex, or cystic nodules (<20% solid tissue within the volume of interest).Results Bipolar RFA resulted in a highly significant (p < 0.0001) decrease of nodule volume (ΔV), median 5.3 mL (range 0.13–43.1 mL), corresponding to a relative reduction in mean of 56 ± 17.9%. Median initial volume was 8 mL (range 0.48–62 mL); 3 months after ablation a median volume of 2.3 mL (range 0.3–32 mL) was measured. Nodule growth ≥50% occurred in 70% (14 nodules). At the follow-up no complications such as infections, persisting pain, nerve injuries or immunogen stimulation occurred. Patients with cold nodules (15) remained euthyroid, with hyperfunctioning nodules either euthyroid (2) or latent hypofunctional (1).Conclusion The use of bipolar RFA is an effective, safe and suitable thermoablative technique to treat benign thyroid nodules. Combined with the multiple overlapping shot technique it allows sufficient ablation.

Thermoablation of Bone Tumors.

The aim of this article is to review the significance of percutaneous thermal ablation in the treatment of bone tumors. We describe available ablation techniques as well as advantages and disadvantages in specific settings. In detail, radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation, high intensity focused ultrasound (HIFU) and cryoablation are presented. In the second part of this review curative and palliative indications for the treatment of benign and malignant bone tumors are discussed. This includes especially RFA, laser or cryoablation for the treatment of osteoid osteoma, as well as the palliative treatment of painful bone metastases, for example, by means of MWA or MR-guided HIFU. • The various thermoablative techniques demonstrate specific advantages and disadvantages.• Radiofrequency ablation is the evidence-based method of choice for treating osteoid osteoma.• Laser ablation is primarily suited for the treatment of small lesions of the hands and feet.• The intrinsically analgesic effect of cryoablation is advantageous when treating painful lesions.• Palliative treatment of painful bone metastases can for example be performed using MWA or MR-guided HIFU, by itself or combined with cementoplasty. Citation Format: • Ringe KI, Panzica M, von Falck C. Thermoablation of Bone Tumors. Fortschr Röntgenstr 2016; 188: 539 - 550.

Stereotactic ablative body radiotherapy for primary kidney cancer: what have we learned from prospective trials and what does the future hold?

10.2217/fon.16.6 © 2016 Future Medicine Ltd In the USA, kidney cancers are currently the 7th and 10th most commonly diagnosed cancers in men and women respectively, with 61,560 new cases expected in 2015, the majority of which will be primary renal cell carcinoma (RCC). Kidney cancer was the 9th most commonly diagnosed cancer in Australia in 2014. Surgical excision is the gold standard for the treatment of primary RCC in fit patients with adequate renal function, with thermoablative techniques such as cryoablation and radiofrequency ablation (RFA) often being utilized in patients who are medically inoperable. More recently, stereotactic ablative body radiotherapy (SABR) is emerging as a promising new weapon in the a rmamentarium against primary RCC. Evidence for efficacy & safety of SABR for primary RCC While RCC is typically considered resistant to radiation delivered using conventional fractionation schedules (1.8–2 Gy per fraction), preclinical evidence indicates that RCC may not be resistant to ablative doses of radiation. Preclinical evidence from Ning et al. suggests that the cell survival curves of two of the most common human RCC cell lines (Caki-1 and A498) exhibited a low α/β ratio (and thus may be sensitive to higher dose per fraction radiation) [1]. The sensitivity of RCC to ablative doses of radiation was suggested by Walsh et al. using a nude mouse model with an implanted human RCC cell line [2]. Biological mechanisms COMMENTARY