Stereotactic Radiofrequency Ablation Research Articles

P.076 Long-term outcomes of radiofrequency ablation for temporal lobe epilepsy

Background: Radiofrequency ablation (RFA) is a minimally-invasive procedure that has been used to treat temporal lobe epilepsy (TLE), however its long-term efficacy is unknown. We aim to characterize the long-term outcomes of patients from the original series by Parrent and Blume (1999). Methods: Consecutive patients who underwent stereotactic RFA for TLE were retrospectively reviewed. Demographics, procedural details, and seizure outcomes until last follow-up were abstracted. Seizure-freedom after initial RFA treatment was estimated with Kaplan-Meier analysis. Results: 27 patients underwent RFA from 1994 to 2002. There were 14 female (52%) patients. 24 (89%) had mesial temporal sclerosis. Mean age at time of RFA was 33.1 years (range 12-45 years). 17 (63%) patients underwent left-sided RFA. 15 (56%) patients had further interventions: 4 (15%) underwent only repeat RFA, 1 (4%) had repeat RFA and anterior temporal lobectomy (ATL), and 10 (37%) underwent subsequent ATL only. Mean follow-up was 9.0 years (range 0.5-22.7 years). At last follow-up, 16 (59%) patients were seizure-free: 5 (19%) received one RFA treatment and 11 (41%) underwent additional procedures. Conclusions: Based on the original series describing the technique, stereotactic RFA for TLE is a safe, minimally-invasive procedure. The role of stereotactic RFA in the treatment of TLE remains to be determined.

Severe Refractory Obsessive Compulsive Disorder and Depression: Should We Consider Stereotactic Neurosurgery?

Functional neurosurgery involves modulation of activity within neural circuits that drive pathological activity. Neurologists and neurosurgeons have worked closely together, advancing the field for over a century, such that neurosurgical procedures for movement disorders are now accepted as "standard of care", benefiting hundreds of thousands of patients. As with movement disorders, some neuropsychiatric illnesses, including obsessive compulsive disorder and depression, can be framed as disorders of neural networks. Over the past two decades, evidence has accumulated that stereotactic neurosurgery can help some patients with mental disorders. Nevertheless, despite the availability of class I evidence for some interventions, there is a huge mismatch between the prevalence of severe refractory mental disorders and the number of referrals made to specialised functional neurosurgery services. This paper examines the historical trajectory of neurosurgery for movement and mental disorders. A review of neurosurgical techniques, including stereotactic radiofrequency ablation, gamma knife, deep brain stimulation, and magnetic resonance imaging guided focused ultrasound, explains the high degree of safety afforded by technological advances in the field. Evidence from clinical trials supporting functional neurosurgery for mental disorders, including obsessive compulsive disorder and depression, is presented. An improved understanding of modern functional neurosurgery should foster collaboration between psychiatry and neurosurgery, providing hope to patients whose symptoms are refractory to all other treatments.

Treatment of intrahepatic cholangiocarcinoma: evidence for the role of percutaneous ablation

Intrahepatic cholangiocarcinoma (iCCA) is a rare cancer with generally poor prognosis. In this narrative review, we examine the role of thermal ablation and summarize the current literature. Radiofrequency ablation (RFA) and microwave ablation (MWA) are both safe and well-tolerated as a minimally invasive local curative treatment option for patients suffering from primary and secondary liver tumors. Both methods can be used in patients with medical morbidities that would preclude surgery, as well as individuals with anatomical or functional constraints that impede liver resection. In unresectable iCCA, the median OS after conventional percutaneous US- or CT-guided RFA and MWA is between 20 and 39 months and 10 and 28 months, respectively. In recurrent iCCA, percutaneous RFA and MWA achieved a median OS of 21-27 months and 21-31 months, respectively. These data are comparable to long-term outcomes after surgical resection (SR), with the number of nodules and tumor size affecting prognosis. Stereotactic radiofrequency ablation (SRFA) allows for effective treatment of large and multiple iCCA nodules within one session and achieves short- and long-term results in inoperable patients compared with resection. With the addition of SRFA as an alternative treatment option, the proportion of patients who can be treated with curative treatment has significantly increased. In the absence of prospective trials comparing thermal ablation and surgical resection, we recommend a patient-specific decision-making process. Future research to identify technical and clinical prognostic criteria, as well as molecular markers of tumor biology, may help select patients for ablation and subsequent outcomes.

Stereotactic ablation: A game changer?

For both primary and metastatic liver cancer, thermal ablation represents an interesting alternative to surgery. However, except for a small fraction of patients, conventional ultrasound- and CT-guided single-probe approaches have not achieved oncologic outcomes comparable with surgery. In this overview, we describe our stereotactic ablation workflow and discuss the short- and long-term results of stereotactic radiofrequency ablation (SRFA) and stereotactic microwave ablation (SMWA)for the treatment of primary and secondary liver tumours. The advantages of this method are discussed together with a summary of the existing stereotactic techniques for thermal ablation and the clinical data that support them. Stereotactic ablation is based on an optical navigation system and a specialized aiming tool. The workflow includes advanced three-dimensional planning, precise needle/probe placements according to the plan and intraoperative image fusion to check the needle positions and the ablation margins. Stereotactic ablation offers all the advantages of a minimally invasive procedure while producing oncological results comparable with surgery. The number of locally treatable liver cancers may be significantly expanded with these cutting-edge instruments and methods. We firmly believe that it can become a cornerstone in the treatment of liver cancers.

Reliability of Stereotactic Radiofrequency Ablation (SRFA) for Malignant Liver Tumors: Novice versus Experienced Operators

To compare the results of a novice with those of experienced interventional radiologists (IRs) for stereotactic radiofrequency ablation (SRFA) of malignant liver tumors in terms of safety, technical success, and local tumor control. A database, including all SRFA procedures performed in a single center between January 2011 and December 2018 was retrospectively analyzed. A total of 39 ablation sessions performed by a novice IR were compared to the results of three more experienced IRs. Comparative SRFA sessions were selected using propensity score matching considering tumor type, age, sex, tumor size, and tumor number as matching variables. Overall, 549 target tumors were treated in 273 sessions. Median tumor size was 2.2 cm (1.0-8.5 cm) for 178 hepatocellular carcinomas (HCCs) and 3.0 cm (0.5-13.0 cm) for 371 metastases. A median of 2 (1-11) tumors were treated per session. No significant differences were observed when comparing the results of more experienced IRs with those of a novice IR regarding the rates of major complications (6.8% [16/234] vs. 5.1% [2/39]; p = 0.477), mortality (1.3% [2/234] vs. 0% [0/39]; p = 0.690), primary technical efficacy (98.5% [525/533] vs. 98.9% [94/95]; p = 0.735), and local recurrence (5.6% [30/533] vs. 5.3% [5/95]; p = 0.886). However, the median planning/placement time was significantly shorter for the experienced IRs (92 min vs. 119 min; p = 0.002). SRFA is a safe, effective, and reliable treatment option for malignant liver tumors and favorable outcomes can be achieved even by inexperienced operators with minimal supervision.

Identification and characterization of patients being exposed to computed-tomography associated radiation-doses above 100 mSv in a real-life setting.

Rationale and objectivesPatients receiving high cumulative effective doses (CED) from recurrent computed tomography (CT) in a real-life setting are not well identified. Evaluation of causes and patient characteristics may help to define individuals potentially at risk of radiation-induced secondary malignancies. Materials and methodsPatients who received a CED > 100 mSv from CT scans during October 2012 and April 2020 at a tertiary university center were identified with the help of a radiological radiation dose monitoring system. The primary disease and referral diagnosis, number of CT exams, time period, age, BMI and gender distribution of the 1000 patients with the highest CED were analysed. Results3431 patients had a CED of more than 100 mSv, which corresponded to 2.75% of all patients who received a CT exam. From the 1000 patients with the highest CED, mean number of CT exams per patient was 14.6, mean CED was 257 mSv (SD 98, range 177–1339). Mean age of patients was 63.9 years (SD 10.6), male to female ratio 3:2, and mean BMI 28.7 kg/m2 (SD 5.5). 728 (72.9%) patients had cancer. The leading primary diagnosis was liver cirrhosis in 197 patients and 103 patients had a liver transplantation. In patients with liver cirrhosis, 750 exams were indicated for the follow-up of the disease, 662 for the clarification of an acute clinical condition, and 202 for CT-guided stereotactic radiofrequency ablation. ConclusionRecurrent CT scans of patients with cancer, liver cirrhosis and liver transplantation may lead to critically high CED.

Multidisciplinary Treatment of Liver Metastases from Intracranial SFTs/HPCs: A Report of Three Consecutive Cases.

In the 2016 WHO classification of tumors of the central nervous system, hemangiopericytomas (HPCs) and solitary fibrous tumors (SFTs) were integrated into a new entity (SFT/HPC). Metastases to bone, liver, lung, and abdominal cavity are of concern. Only 37 cases of patients with liver metastases due to intracranial SFTs/HPCs have been reported. Herein, we present our experience in the management of patients with liver metastases from intracranial SFTs/HCPs. All consecutive patients who were treated for liver metastases from intracranial SFTs/HPCs from January 2014 to December 2020 were enrolled. Overall, three patients were treated for liver metastasis from SFTs/HPCs with curative intent. Two patients with bilobar metastases at presentation required surgical resection, transarterial embolization, stereotactic radiofrequency ablation (SRFA) and systemic therapy. One patient with a singular right liver lobe metastasis was treated with SRFA alone. This patient shows no evidence of liver metastases 39 months following diagnosis. Of the two patients with bilobar disease, one died 89 months following diagnosis, while one is still alive 73 months following diagnosis. Long-term survival can be achieved using a multimodal treatment concept, including surgery, loco-regional and systemic therapies. Referral to a specialized tertiary cancer center and comprehensive long-term follow-up examinations are essential.

Stereotactic Radiofrequency Ablation for Treatment-Refractory Depression: A Systematic Review and Meta-Analysis.

(1) Background: Major depressive disorder (MDD) generates a large proportion of global disease burden. Stereotactic radiofrequency ablation (SRA) may be beneficial for selected patients with its most debilitating and refractory forms, but effect size is uncertain. (2) Methods: A systematic literature review and meta-analysis on SRA for MDD was carried out. Patient-level data were extracted from articles reporting validated depression measures (Beck Depression Inventory (BDI), Montgomery–Åsberg Depression Rating Scale (MADRS)), pre- and at least six months post surgery. To accommodate different outcome measures, the standardised mean difference (SMD) between both scores was used as the principal effect size. Data were synthesised using a random-effects model. (3) Results: Five distinct studies were identified, comprising 116 patients (64 included in meta-analysis). Effect size comparing post- vs. pre-operative scores was 1.66 (CI 1.25–2.07). Anterior cingulotomy (two studies, n = 22) and anterior capsulotomy (three studies, n = 42) showed similar effect sizes: 1.51 (CI 0.82–2.20) vs. 1.74 (CI 1.23–2.26). Multiple procedures were performed in 30 of 116 (25.9%) patients. Based on patient-level data, 53% (n = 47) were responders (≥50% improvement), of which 34% reached remission (MADRS ≤ 10 or BDI ≤ 11). BDI mean improvement was 16.7 (44.0%) after a second procedure (n = 19). (4) Conclusions: The results are supportive of the benefit of SRA in selected patients with refractory MDD.

Stereotactic radiofrequency ablation of tumors at the hepatic venous confluence.

Radiofrequency ablation (RFA) is subject to "heat-sink" effects, particularly for treatment of tumors adjacent to major vessels. In this retrospective study, 104 patients with 137 tumors (40 HCC, 10 ICC and 54 metastatic liver tumors) close to (≤1cm from) the hepatic venous confluence underwent stereotactic RFA (SRFA) between June 2003 and June 2018. Median tumor size was 3.7cm (1.4-8.5) for HCC, 6.4cm (0.5-11) for ICC and 3.8cm (0.5-13) for metastases. Endpoints comprised safety, local tumor control, overall and disease-free survival. The overall major complication rate was 16.0% (20/125 ablations), where 8 (40%) were successfully treated by the interventional radiologist in the same anesthetic session and did not prolong hospital stay. 134/137 (97.8%) tumors were successfully ablated at initial SRFA. Local recurrence (LR) developed in 19/137 tumors (13.9%). The median and overall survival (OS) rates at 1-, 3-, and 5- years from the date of the first SRFA were 51.5 months, 73.5%, 67.0%, and 49.7% for HCC, 14.6 months, 60.0%, 32.0% and 32.0% for ICC and 38.1 months, 91.4%, 56.5% and 27.9% for metastatic disease, respectively. SRFA represents a viable alternative to hepatic resection for challenging tumors at the hepatic venous confluence.

False-positive findings on 18-Fluoro-deoxy-glucose positron emission tomography due to granulomatous inflammation in a rectal cancer patient with an extensive tattoo

Introduction: In patients with colorectal cancer a combined 18-Fluoro-deoxy-glucose positron emission tomography with computed tomography (CT) may be useful in advanced or recurrent disease to assess distant metastases. In the interpretation several pitfalls must be considered. Case Report: A 37-year-old woman presented with metachronous liver metastases three years after the first diagnosis of rectal cancer. A second-line chemotherapy and stereotactic radiofrequency ablation was performed. Six months after the intervention, the follow-up magnetic resonance imaging revealed new liver lesions with indefinite diffusion impairment and pathologic contrast enhancement in portal venous and hepatobiliary phase. Further investigation with combined 18-Fluoro-deoxy-glucose positron emission tomography with CT showed for malignancy suspicious glucose-uptake in the respective liver lesions and additional in unilateral enlarged inguinal lymph nodes. Because of the uncommon findings, histologic specimen was obtained. Histology revealed no malignancy, but granulomatous hepatitis and lymphadenitis consistent with sarcoid-like reaction. Furthermore, deposition of tattoo pigment was found in the enlarged lymph nodes, most likely deriving from a large tattoo located on the right lower extremity. Conclusion: We describe a case of a rectal cancer patient with misleading imaging findings on combined 18-Fluoro-deoxy-glucose positron emission tomography with CT. Awareness of rare conditions such as granulomatous inflammation and false-positive findings is key in the presence of uncommon findings, like in this case, suggested spread outside the metastatic pathway.

Stereotactic radiofrequency ablation as a valid first-line treatment option for hepatocellular adenomas

Objectives This study aimed to assess the safety and efficacy of stereotactic radiofrequency ablation (SRFA) in patients with hepatocellular adenomas (HCA). Methods Retrospective analyses of all patients referred for SRFA treatment at our institution between January 2010 and October 2020 revealed 14 patients (10 women; mean age 34.4 [range, 17–73 years]) with 38 HCAs treated through 18 ablation sessions. Ablations were considered successful if a safety margin >5 mm was achieved. Demographic, interventional, and outcome data were collected and analyzed. Primary and secondary technical efficacy rates were assessed based on follow-up images consisting of contrast-enhanced CT or MR scans. Results The mean tumor size was 22 mm (range, 7–75 mm). Overall, 37/38 (97.4%) tumors were successfully ablated at the initial SRFA (primary efficacy rate of 97.4%). The median follow-up duration was 49.6 months. No deaths or adenoma-related complications (hemorrhage or malignant transformation) were observed. Disease-free survival rates at 1, 3, and 5 years from the date of the first SRFA were 100%, 85.8%, and 85.8%, respectively. Two patients developed new distant tumors retreated with consecutive re-ablation. No major complications occurred during any of the 18 ablation sessions. Conclusions Percutaneous thermal ablation is efficient in the treatment of HCAs and may thus be considered a valid first-line treatment option. In addition, SRFA allows for an effective, minimally invasive treatment of large and multiple hepatic tumors within one session.

Technical efficacy and local recurrence after stereotactic radiofrequency ablation of 2653 liver tumors: a 15-year single-center experience with evaluation of prognostic factors

Purpose To assess the technical outcome and local tumor control of multi-probe stereotactic radiofrequency ablation (SRFA) in a large series of patients. Furthermore, to determine factors accounting for adverse outcomes. Material and methods Between 2003 and 2018, 865 patients were treated by SRFA for 2653 primary and metastatic liver tumors with a median tumor size of 2.0 cm (0.5 − 19 cm). Primary technical efficacy (PTE) and local recurrence (LR) were evaluated, and possible predictors for adverse events analyzed using uni- and multi-variable binary logistic regression. Results Overall, 2553 of 2653 tumors were successfully ablated at initial SRFA resulting in a PTE rate of 96.2%. Predictors of lower PTE rates were age > 70 years, tumor size > 5 cm, number of probes, location close to liver capsule/organs and segment II. LR occurred in 220 of 2653 tumors (8.3%) with the following predictors: age, tumor type/size, conglomerates, segments I/IVa/IVb, number of probes and location close to major vessels/bile duct. Multivariable analysis revealed tumor size > 5 cm (odds ratio [OR] 3.153), age > 70 years (OR 1.559), and location in segment II (OR 1.772) as independent prognostic factors for PTE, whereas tumor location close to major vessels (OR 1.653) and in segment IVb (OR 2.656) were identified as independent prognostic factors of LR. Conclusions Stereotactic RFA is an attractive option in the management of primary or metastatic liver tumors with good local tumor control, even in large tumors. The presented prognostic factors for adverse local oncological outcome might help to stratify unfavorable tumors for ablation.

A prospective randomized parallel-controlled pilot trial of stereotactic body radiation therapy versus radiofrequency ablation for the management of small renal masses.

363 Background: The potential of ablative technologies as an alternative to surgery for the treatment of small renal masses (SRMs) ≤4cm is unclear. Our objective was to evaluate the feasibility and toxicity of stereotactic body radiation therapy (SBRT) and radiofrequency ablation (RFA) for SRMs in a prospective randomized pilot trial. Methods: Patients scheduled for renal cell carcinoma (RCC) treatment at a single academic center were approached for the pilot trial, with the aim of recruiting 24 patients. Participants were assigned 1:1 to SBRT or RFA. Imaging (CT or MRI) using a renal tumor protocol is completed at 3, 6, 9, and 12 months post-procedure. Biopsies were completed prior to the procedure and at 12 months. Multiple clinical parameters were collected. Follow-up visits will occur at 6 month intervals following the trial up to 5 years. SBRT included an initial simulation session and a single image-guided treatment session with a prescribed dose of 25 Gy. RFA was conducted by either percutaneous or laparoscopic access with 2 cycles of 8 minutes duration each upon reaching target temperature. Results: Beginning in December 2019, 24 patients were recruited and randomized (SBRT = 11; RFA = 13). Eleven had SBRT, 8 RFA, 3 have not yet had treatment, and 2 became ineligible. Median age for all patients was 67 (53,85) and 17 were male. A total of 17 patients had clear cell RCC, 6 had papillary RCC (type 1), and 1 had chromophobe RCC. All patients had T1a disease. Mean procedure length (minutes) for SBRT and RFA was 15.5±7.4 and 10.5±3.9, respectively. Two patients (both SBRT) had a 12-month biopsy showing no evidence of recurrence or metastases, while two patients (1 RFA, 1 SBRT) had a 9-month CT showing no recurrence. Data are pending for the remaining patients. An early grade 2 flare-up occurred in one SBRT patient. Conclusions: Recruitment and randomization of patients with SRMs in a SBRT vs. RFA prospective trial is feasible on a timeline that allows for regular follow-up and imaging. To date, both treatment modalities have been shown to have excellent short-term safety profiles.

Aggressive local treatment for recurrent intrahepatic cholangiocarcinoma – stereotactic radiofrequency ablation as a valuable addition to hepatic resection

Aggressive local treatment for recurrent intrahepatic cholangiocarcinoma – stereotactic radiofrequency ablation as a valuable addition to hepatic resection

Aggressive local treatment for recurrent intrahepatic cholangiocarcinoma—Stereotactic radiofrequency ablation as a valuable addition to hepatic resection

BackgroundTo evaluate the efficacy, safety and overall clinical outcome of local treatment for recurrent intrahepatic cholangiocellular carcinoma after hepatic resection.MethodsBetween 2007 and 2019 72 consecutive patients underwent hepatic resection for primary intrahepatic cholangiocellular carcinoma. If amenable, recurrent tumors were aggressively treated by HR or stereotactic radiofrequency ablation with local curative intent. Endpoints consisted of morbidity and mortality, locoregional and de novo recurrence, disease free survival, and overall survival.ResultsAfter a median follow-up of 28 months, recurrence of intrahepatic cholangiocellular carcinoma was observed in 43 of 72 patients undergoing hepatic resection (60.3%). 16 patients were subsequently treated by hepatic resection (n = 5) and stereotactic radiofrequency ablation (n = 11) with local curative intention. The remaining 27 patients underwent palliative treatment for first recurrence. Overall survival of patients who underwent repeated aggressive liver-directed therapy was comparable to patients without recurrence (p = 0.938) and was better as compared to patients receiving palliative treatment (p = 0.018). The 5-year overall survival rates for patients without recurrence, the repeated liver-directed treatment group and the palliative treatment group were 54.3%, 47.7% and 12.3%, respectively. By adding stereotactic radiofrequency ablation as an alternative treatment option, the rate of curative re-treatment increased from 11.9% to 37.2%.ConclusionRepeated hepatic resection is often precluded due to patient morbidity or anatomical and functional limitations. Due to the application of stereotactic radiofrequency ablation in case of recurrent intrahepatic cholangiocellular carcinoma, the number of patients treated with curative intent can be increased. This leads to favorable clinical outcome as compared to palliative treatment of intrahepatic cholangiocellular carcinoma recurrence.

Optimal application of stereotactic body radiotherapy and radiofrequency ablation treatment for different multifocal hepatocellular carcinoma lesions in patients with Barcelona Clinic Liver Cancer stage A4\u2013B1: a pilot study

BackgroundIn clinical practice, many hepatocellular carcinoma (HCC) patients in Barcelona Clinical Liver Cancer (BCLC) stage A4–B1 cannot receive the curative treatments of liver transplantation, resection, and radiofrequency ablation (RFA), which are the recommended options according to liver cancer guidelines. Our aim is to study the feasibility of RFA and stereotactic body radiotherapy (SBRT) as a curative treatment for different multifocal HCCs in BCLC stage A4–B1 patients.MethodsFrom September 2014 to August 2019, 39 multifocal HCC lesions (median diameter: 16.6 mm) from 15 patients (median age: 73 years) were retrospectively selected. Among them, 23 were treated by RFA and the other 16 by SBRT because of predictable insufficiency and/or risk related to RFA performance. The indicators for evaluating this novel therapy were the tumor response, prognosis (recurrence and survival), and adverse effects (deterioration of laboratory test values and severe complications).ResultsThe median follow-up duration was 31.3 months (range: 15.1–71.9 months). The total patients with a one-year complete response, stable disease, or disease progression were 11, 1, and 3, respectively. In total, 8 and 2 patients had confronted intrahepatic or local recurrence, respectively. The one-year progression-free survival rate and local control rate were 80% (12/15 patients) and 97.4% (38/39 lesions), respectively. The median time to progression was 20.1 (2.8–45.1) months. The one- and two-year survival rates were 100 and 88.9%, respectively. In up to five months’ observation, no patient showed severe complications. Seven, four, and two patients had slight changes in their white blood cells, platelet count, or albumin–bilirubin grade, respectively.ConclusionsFor patients with BCLC stage A4–B1, RFA and SBRT treatment for different multifocal HCCs may be a potential option because of the favorable prognosis and safety. However, before its application in clinical practice, prospective, controlled, large-scale studies are needed to further confirm our conclusions.

Radiofrequency Ablation for Movement Disorders: Risk Factors for Intracerebral Hemorrhage, a Retrospective Analysis.

One of the greatest concerns associated with radiofrequency ablation is intracerebral hemorrhage (ICH). However, the majority of previous studies have mainly evaluated Parkinson disease patients with ablation of the globus pallidus internus (GPi). To investigate the hemorrhagic risk associated with radiofrequency ablation using ventro-oral (Vo) nucleus, ventral intermediate (Vim) nucleus, GPi, and pallidothalamic tract. Radiofrequency ablations for movement disorders from 2012 to 2019 at our institution were retrospectively analyzed. Multivariate analyses were performed to evaluate associations between potential risk factors and ICH. A total of 558 patients underwent 721 stereotactic radiofrequency ablations for movement disorders. Among 558 patients, 356 had dystonia, 111 had essential tremor, and 51 had Parkinson disease. Among 721 procedures, the stereotactic targets used in this study were as follows: Vo: 230; Vim: 199; GPi: 172; pallidothalamic tract: 102; Vim/Vo: 18. ICH occurred in 37 patients (5.1%, 33 with dystonia and 4 with essential tremor). Symptomatic ICH developed in 3 Vo nuclei (1.3%), 3 Vim nuclei (1.5%), and 2 GPi (1.2%). Hypertension (odds ratio=2.69, P=.0013), higher number of lesions (odds ratio=1.23, P=.0221), and younger age (odds ratio=1.04, P=.0055) were significant risk factors for ICH associated with radiofrequency ablation. The present study revealed that younger age, higher number of lesions, and history of hypertension were independent risk factors for ICH associated with stereotactic radiofrequency ablation.

Contralateral insular epileptogenic hub causing seizure relapse after opercular focal cortical dysplasia surgery and response to radiofrequency thermocoagulation: illustrative case.

BACKGROUNDThe reevaluation and management of seizure relapse following resective surgery in magnetic resonance imaging (MRI)-negative pharmacoresistant epilepsy remains a significant challenge.OBSERVATIONSA 25-year-old right-handed male with medically refractory epilepsy presented with nonlocalizing electroencephalography (EEG) and MRI. Stereo-EEG (SEEG) implantation based on semiology and positron emission tomography imaging revealed a left frontal opercular focus with rapid bilateral insular ictal synchrony. The initial epileptogenic zone was resected and pathologically proven to be type 2A focal cortical dysplasia (FCD). Seizure relapse after 9 months was eventually reinvestigated, and repeat SEEG revealed a secondary epileptogenic focus in the contralateral insula. A novel technique of volumetric stereotactic radiofrequency ablation (vRFA) was utilized for the right insular focus, following which, the patient remains seizure-free for 20 months. He suffered a transient bilateral opercular syndrome following the second intervention that eventually resolved.LESSONSThe authors present clinical evidence to suggest epileptogenic nodes distant from the primary focus as a mechanism for seizure relapse following FCD surgery and the importance of bilateral insular SEEG coverage. The authors also describe a novel technique of minimally invasive vRFA that allows ablation of a larger volume of cerebral cortex when compared to conventional bedside SEEG electrode thermocoagulation.

Stereotactic Thermal Ablation of Liver Tumors: 3D Planning, Multiple Needle Approach, and Intraprocedural Image Fusion Are the Key to Success—A Narrative Review

Simple SummaryThermal ablation is a minimally invasive, potentially curative approach for the treatment of primary and secondary liver tumors. Different technologies are available, with radiofrequency ablation (RFA) and microwave ablation (MWA) being the most widely used. Both methods induce an irreverible destruction of the tumor tissue by applying thermal energy. Conventionally, a single ablation probe is placed using ultrasound (US) or computed tomography (CT). Using these standard guidance techniques the creation of necrosis zones to treat large tumors (i.e., >2–3 cm) is hampered by technical limitations. These limitations can be overcome by stereotactic thermal ablation: a multiple needle approach with 3D treatment planning and precise stereotactic needle placement combined with immediate verification of treatment success by means of image fusion. The stereotactic multi-needle technique allows for local curative treatment of multiple and large tumors within a single session. Ultimately, due to the application of these sophisticated tools and advanced techniques, a local curative treatment option can be offered to a higher number of patients suffering of primary and secondary liver tumors. This article provides an overview of the current stereotactic techniques for thermal ablation and summarizes the available clinical evidence for this approach.Thermal ablation is an emerging, potentially curative approach in treating primary and metastatic liver cancer. Different technologies are available, with radiofrequency ablation (RFA) and microwave ablation (MWA) being the most widely used. Regardless of the technique, destruction of the entire tumor, including an adequate safety margin, is key. In conventional single-probe US- or CT-guided thermal ablation, the creation of such large necrosis zones is often hampered by technical limitations, especially for large tumors (i.e., >2–3 cm). These limitations have been overcome by stereotactic RFA (SRFA): a multiple needle approach with 3D treatment planning and precise stereotactic needle placement combined with intraprocedural image fusion of pre- and post-interventional CT scans for verification of treatment success. With these sophisticated tools and advanced techniques, the spectrum of locally curable liver malignancies can be dramatically increased. Thus, we strongly believe that stereotactic thermal ablation can become a cornerstone in the treatment of liver malignancies, as it offers all the benefits of a minimally invasive method while providing oncological outcomes comparable to surgery. This article provides an overview of current stereotactic techniques for thermal ablation, summarizes the available clinical evidence for this approach, and discusses its advantages.

Commentary: Stereotactic Body Radiotherapy vs. Radiofrequency Ablation in the Treatment of Hepatocellular Carcinoma: A Meta-Analysis.

Commentary: Stereotactic Body Radiotherapy vs. Radiofrequency Ablation in the Treatment of Hepatocellular Carcinoma: A Meta-Analysis.