Contribution and advances of robotics in percutaneous oncological interventional radiology.

The advent of robotic systems in interventional radiology marks a significant evolution in minimally invasive medical procedures, offering enhanced precision, safety, and efficiency. This review comprehensively analyzes the current state and applications of robotic system usage in interventional radiology, which can be particularly helpful for complex procedures and in challenging anatomical regions. Robotic systems can improve the accuracy of interventions like microwave ablation, radiofrequency ablation, and irreversible electroporation. Indeed, studies have shown a notable decrease of an average 30% in the mean deviation of probes, and a 40% lesser need for adjustments during interventions carried out with robotic assistance. Moreover, this review highlights a 35% reduction in radiation dose and a stable-to-30% reduction in operating time associated with robot-assisted procedures compared to manual methods. Additionally, the potential of robotic systems to standardize procedures and minimize complications is discussed, along with the challenges they pose, such as setup duration, organ movement, and a lack of tactile feedback. Despite these advancements, the field still grapples with a dearth of randomized controlled trials, which underscores the need for more robust evidence to validate the efficacy and safety of robotic system usage in interventional radiology.

Current opinion: optimize radiofrequency ablation through electrophysiological principles, modeling, and clinical recommendations.

PURPOSE OF REVIEW: This article aims to empower the interventional pain physician to utilize RFA effectively by explaining the technical and electrophysiological features of monopolar, bipolar, and internally cooled RFA. Scientific data are used to provide advice on the effective, well tolerated, and rational application of these techniques. Moreover, physicians need to know how to analyze and generalize ex-vivo and in-vivo models to the clinical setting to optimize clinical outcomes. RECENT FINDINGS: Recent studies suggest that there are many ways to enhance the technical effectiveness of interventional pain medicine RFA through adjustments in the equipment selection and settings and the local tissue conditions specific to the targeted anatomical area. These modifications could assist in improving clinical and safety outcomes. SUMMARY: To optimize both the efficacy and safety of RFA, physicians must understand, conceptualize, interpret, and clinically translate the basic science of RFA. This knowledge is crucial for optimizing equipment selection and settings based on target location to enhance clinical outcomes and limit technical failures.

Adjustable-tip needles versus fixed-tip needles in radiofrequency ablation of symptomatic benign thyroid nodules: a single-center Italian experience.

PURPOSE: In this retrospective, observational study we aim to compare the outcomes of the RFA treatment of benign thyroid nodules, carried out respectively with the standard fixed-needle approach (FTN) and the adjustable-tip needle technique (ATN), considered a more tailored, quicker and easier technical approach. METHODS: We enrolled 36 patients who underwent RFA treatment of symptomatic, benign, thyroid nodule, 18 with the ATN and 18 with the FTN approach, respectively. Data about absolute volume reduction, volume reduction rate (VRR) and success rate (defined as VRR ≥ 50%), after 1, 3 and 6 months of follow-up were compared. RESULTS: Our study suggested no substantial difference between the approaches, up to 6 months of follow-up, both in terms of absolute reduction (p = 0.27) and VRR (p = 0.14). These results were confirmed when the success rates, both in terms of 50%-reduction (p = 0.12) and absolute reduction (p = 0.42), was considered. Only at the 6-month evaluation, the FTN procedure showed a better success rate, yet without statistical significance (88.9% vs. 61.1%, p = 0.12). No difference emerged both in terms of patients' satisfaction and safety. CONCLUSION: Our small experience suggested no substantial difference between ATN and FTN, in terms of outcomes. On the other hand, ATN was considered to be more straightforward and could consequently allow for a shorter operator learning curve.

Real-Time Internal Steam Pop Detection during Radiofrequency Ablation with a Radiofrequency Ablation Needle Integrated with a Temperature and Pressure Sensor: Preclinical and Clinical Pilot Tests.

A radiofrequency ablation (RFA) needle integrated with a temperature sensor (T-sensor) and pressure sensor (P-sensor) is designed and utilized for real-time internal steam pop monitoring during RFA. The characteristics of the sensor-integrated RFA needle (sRFA-needle) are investigated quantitatively using a pressure chamber system, and the feasibility and usability of the needle in preclinical and clinical trials is demonstrated. The sharp changes in the temperature and normalized pressure sensor signals induced by the abrupt release of hot and high-pressure steam can be clearly monitored during the steam pop phenomena. The basic mechanism of the preliminary steam pop is hypothesized and verified using in situ ultrasound imaging data and computational analysis data of the RFA procedure. Moreover, the usability of the system in clinical trials is investigated, and the steam pop phenomena during the RFA procedure are detected using T-sensor and P-sensor. The results confirm that the sensor integration on the medical needle can provide critical data for safer and more effective medical practices.

Steerable needles for radio-frequency ablation in cirrhotic livers.

Accurate needle placement in deep-seated liver tumours can be difficult. In this work, we disclose two new manually controlled steerable needles for 17G radio-frequency ablation probe placement. The needles contain stylets with embedded compliant joints for active tip articulations, and concentric tubes for (curved-path) guidance. Needle steering was evaluated sequentially by intended users and in intended-use tissue types. Six interventional radiologists evaluated the needle in repeated ultrasound-guided steering tasks in liver-mimicking phantoms. Targets were located at a 100 mm depth and 20 mm lateral offset from the initial insertion line. The resulting mean absolute tip placement error was 1.0 ± 1.0 mm. Subsequently, steering-induced tissue damage was evaluated in fresh cirrhotic human liver explants. The surface area of puncture holes was estimated in scanned histology slides, using a connected-components analysis. The mean surface area was 0.26 ± 0.16 mm2 after steering with a median radius of curvature of 0.7 × 103 mm, versus 0.35 ± 0.15 mm2 after straight-path insertions with the steerable needle and 0.15 ± 0.09 mm2 after straight-path RFA probe insertions. The steering mechanisms proposed enable clinically relevant path corrections for 17G needles. Radiologists were quickly adept in curved-path RFA probe placement and the evaluation of histological tissue damage demonstrated a potentially safe use during liver interventions.

Laparoscopic transperitoneal adrenalectomy: a comparative study of different techniques for vessel sealing.

BACKGROUND: Laparoscopic adrenalectomy is the standard surgical approach to adrenal lesions. Adrenal vessel sealing is the critical surgical phase of laparoscopic adrenalectomy. This study aimed at comparing perioperative outcomes of laparoscopic transperitoneal adrenalectomy by means of radiofrequency energy-based device (LARFD) to those performed with traditional clipping device (LACD), while focusing on the different adrenal vessel control techniques. METHODS: Patients who underwent adrenalectomy for adrenal disease between January 1994 and April 2019 at the Surgical Clinic, Polytechnic University of Marche were included in the study. Overall, 414 patients met inclusion criteria for study eligibility: 211 and 203 patients underwent LARFD and LACD, respectively. Multiple models of quantile regression, logistic regression and Poisson finite mixture regression were used to assess the relationship between operative time, conversion to open procedure, length of stay (LoS), surgical procedure and patient characteristics, respectively. RESULTS: LARFD reduced operative time of about 12 min compared to LACD. Additional operative time-related factors were surgery side, surgery approach, conversion to open procedure and trocar number. The probability of conversion to open procedure decreased by about 76% for each added trocar, whereas it increased by about 49% for each added centimeter of adrenal lesion and by about 25% for each added year of surgery. Two patient clusters were identified based on the LoS: long-stay and short-stay. In the long-stay cluster, LoS decreased of about 30% in LARFD group and it was significantly associated with conversion to open procedure and postoperative complications, whereas in short-stay cluster only postoperative complications had a significant effect on LoS. CONCLUSION: Laparoscopic transperitoneal adrenalectomy performed by means of radiofrequency energy-based device for the sealing of adrenal vessels is an effective procedure reducing operative time with potentially improved postoperative outcomes.

Prospective comparative study of different endovenous thermal ablation systems for treatment of great saphenous vein reflux.

OBJECTIVE: The aim of our study was to compare three different endovenous thermal ablation (EVTA) modalities in the treatment of great saphenous vein (GSV) incompetence. METHODS: We performed a single-center, prospective, comparative cohort study that included consecutive patients undergoing EVTA of the GSV. Patients were treated with either segmental radiofrequency ablation (sRFA) or endovenous laser ablation (EVLA) with a 1470-nm dual radial fiber or with a 1470-nm jacket-tip fiber. The clinical classification CEAP (clinical, etiologic, anatomic, pathophysiologic), 10-cm visual analog scale scores for pain, Venous Clinical Severity Scores (VCSSs), and chronic venous insufficiency quality-of-life questionnaire (CIVIQ-20) scores were recorded. The primary outcome was clinical success, which was defined as the absence of reflux or recanalization of the GSV and procedure-related complications, assessed at 7 and 30 days and 1 year postoperatively. The secondary outcomes were the assessment of postoperative pain using the VAS and improvement in the VCSSs and CIVIQ-20 scores. RESULTS: A total of 153 patients (160 limbs) had undergone sRFA (sRFA group; n = 53 limbs), 1470-nm radial fiber EVLA (EVLA-R group; n = 55 limbs), or 1470-nm jacket-tip fiber EVLA (EVLA-J group; n = 52 limbs). The patient demographics, CEAP clinical class, and intraoperative details were comparable among the three groups. The GSV occlusion rate at 1 year was 93% in the sRFA group, 93% in the EVLA-R group, and 95% in the EVLA-J group. No major complications were observed postoperatively. Endothermal heat-induced thrombosis was observed in 2 (4.4%), 1 (2.2%), and 2 (4.4%) patients in the sRFA, EVLA-R, and EVLA-J groups, respectively (P > .5). The VCSS showed greater improvement in the EVLA-R group at 1 week compared with that in the sRFA (P = .05) and EVLA-J (P = .002) groups. Changes in the CIVIQ-20 score were in favor of the EVLA-R group at 7 days (-14.3 ± 10.3 vs -7.9 ± 5.9; adjusted difference, 6.06; 95% confidence interval [CI], 1.57-10.55; P = .01) and 30 days (-12 ± 8 vs -11.2 ± 7; adjusted difference, 5.5; 95% CI, 1.21-9.81; P = .02) postoperatively compared with the sRFA group and at 7 days compared with the EVLA-J group (-14.3 ± 10.3 vs -9.6 ± 7.9; adjusted difference, -4.4; 95% CI, -9.06 to 0.22; P = .05). Analyzing the different components of the CIVIQ-20, pain, and physical scores showed a greater reduction in the EVLA-R group in the early postoperative period compared with that in the sRFA and EVLA-J groups. CONCLUSIONS: All three EVTA modalities showed equal effectiveness and safety for the treatment of GSV reflux. EVLA with the 1470-nm radial fiber showed better outcomes in terms of early postoperative VCSSs and pain and physical CIVIQ scores. The clinical and quality of life benefits were similar for all modalities at 1 year postoperatively.

Efficacy and safety of palliative endobiliary radiofrequency ablation using a novel temperature-controlled catheter for malignant biliary stricture: a single-center prospective randomized phase II TRIAL.

BACKGROUND: Endobiliary radiofrequency ablation (EB-RFA) has emerged as a palliative treatment for malignant biliary strictures (MBSs); however, concerns about complications related to thermal injury remain. In this study, we evaluated the efficacy and safety of EB-RFA with a novel catheter for MBS. METHODS: Patients with inoperable cancer causing MBS were randomly assigned to either the radiofrequency ablation (RFA) group or the non-RFA group. The RFA group underwent EB-RFA at the stricture site with a temperature-controlled catheter (ELRA™; STARmed Co., Goyang, Korea) followed by deployment of a self-expanding metal stent (SEMS). For the non-RFA group, only SEMS placement was performed. The duration of stent patency, overall survival (OS), and 30-day complication rate were evaluated. This trial was registered at ClinicalTrials.gov (number NCT02646514). RESULTS: A total of 48 patients were enrolled (24 in each group). During a median follow-up period of 135.0 days (RFA group) and 119.5 days (non-RFA group), the 90-day stent patency rate, median duration of stent patency, and median OS were not different between the groups (58.3% vs. 45.8% [P = 0.386], 132.0 days vs. 116.0 days [P = 0.440], and 244.0 days vs. 180.0 days [P = 0.281], respectively). In the RFA group, procedure-related complications including thermal injury-related complications, such as bile duct perforation or hemobilia, were not reported. The early complication (< 7 days) rates were not different between the groups (4.2% vs. 12.5%, P = 0.609), and there were no late complications (7-30 days) in both groups. CONCLUSION: EB-RFA with a temperature-controlled catheter followed by SEMS placement for patients with inoperable MBS can be safe and feasible with acceptable biliary patency.

Prostate Radiofrequency Focal Ablation (ProRAFT) Trial: A Prospective Development Study Evaluating a Bipolar Radiofrequency Device to Treat Prostate Cancer.

PURPOSE: We determined the early efficacy of bipolar radiofrequency ablation with a coil design for focal ablation of clinically significant localized prostate cancer visible at multiparametric magnetic resonance imaging. MATERIALS AND METHODS: A prospective IDEAL phase 2 development study (Focal Prostate Radiofrequency Ablation, NCT02294903) recruited treatment-naïve patients with a single focus of significant localized prostate cancer (Gleason 7 or 4 mm or more of Gleason 6) concordant with a lesion visible on multiparametric magnetic resonance imaging. Intervention was a focal ablation with a bipolar radiofrequency system (Encage™) encompassing the lesion and a predefined margin using nonrigid magnetic resonance imaging-ultrasound fusion. Primary outcome was the proportion of men with absence of significant localized disease on biopsy at 6 months. Trial followup consisted of serum prostate specific antigen, multiparametric magnetic resonance imaging at 1 week, and 6 and 12 months post-ablation. Validated patient reported outcome measures for urinary, erectile and bowel functions, and adverse events monitoring system were used. Analyses were done on a per-protocol basis. RESULTS: Of 21 patients recruited 20 received the intervention. Baseline characteristics were median age 66 years (IQR 63-69) and preoperative median prostate specific antigen 7.9 ng/ml (5.3-9.6). A total of 18 patients (90%) had Gleason 7 disease with median maximum cancer 7 mm (IQR 5-10), for a median of 2.8 cc multiparametric magnetic resonance imaging lesions (IQR 1.4-4.8). Targeted biopsy of the treated area (median number of cores 6, IQR 5-8) showed absence of significant localized prostate cancer in 16/20 men (80%), concordant with multiparametric magnetic resonance imaging. There was a low profile of side effects at patient reported outcome measures analysis and there were no serious adverse events. CONCLUSIONS: Focal therapy of significant localized prostate cancer associated with a magnetic resonance imaging lesion using bipolar radiofrequency showed early efficacy to ablate cancer with low rates of genitourinary and rectal side effects.

Plume Effect of Fractional Radiofrequency Verus Laser Resurfacing: Considerations in the COVID-19 Pandemic.

INTRODUCTION: The COVID-19 pandemic requires us all to re-evaluate aesthetic practices to ensure optimal patient safety during elective procedures. Specifically, energy-based devices and lasers require special consideration, as they may emit plume which has been shown to contain tissue debris and aerosolized biological materials. Prior studies have shown transmission of viruses and bacteria via plume (i.e., HIV and papillomavirus). The purpose of this study was to evaluate plume characteristics of the Er:YAG resurfacing laser (Sciton; Palo Alto, CA) and compare it to the Morpheus8 fractional radiofrequency device (InMode; Lake Forest, CA). METHODS: Five patients who underwent aesthetic resurfacing and/or skin tightening of the face and neck were treated with the Er:YAG (Sciton Joule, Palo Alto, CA) and/or fractional radiofrequency (Morpheus8, Lake Forest, CA) between April 1 and May 11, 2020. Data collected included patient demographics, past medical history, treatment parameters, adverse events, particle counter data, as well as high magnification video equiptment. Patients were evaluated during treatment with a calibrated particle meter (PCE; Jupiter, FL). The particle meter was used at a consistent focal distance (6-12 inches) to sample the surrounding environment during treatment at 2.83 L/min to a counting efficiency of 50% at 0.3 µm and 100% at >0.45 µm. Recordings were obtained with and without a smoke evacuator. RESULTS: Of our cohort (n = 5), average age was 58 years old (STD ±7.2). Average Fitzpatrick type was between 2 and 3. Two patients received Er:YAG fractional resurfacing in addition to fractional radiofrequency during the same treatment session. Two patients had fractional radiofrequency only, and one patient had laser treatment with the Er:YAG only. There were no adverse events recorded. The particle counter demonstrated ambient baseline particles/second (pps) at 8 (STD ±6). During fractional radiofrequency treatment at 1-mm depth, the mean recording was 8 pps (STD ±8). At the more superficial depth of 0.5 mm, recordings showed 10 pps (STD ±6). The Er:YAG laser resurfacing laser had mean readings of 44 pps (STD ±11). When the particle sizes were broken down by size, the fractional radiofrequency device had overall smaller particle sizes with a count of 251 for 0.3 µm (STD ±147) compared with Er:YAG laser with a count of 112 for 0.3 µm (STD ±84). The fractional radiofrequency did not appear to emit particles >5 µm throughout the treatment, however, the Er:YAG laser consistently recorded majority of particles in the range of 5-10 µm. The addition of the smoke evacuator demonstrated a 50% reduction in both particles per second recorded as well as all particle sizes. CONCLUSION: Re-evaluation of the plume effect from aesthetic devices has become important during the COVID-19 pandemic. Further studies are required to characterize viability of COVID-19 viability and transmissibility in plume specimens. Based on this pilot study, we recommend that devices that generate little to no plume such as fractional radiofrequency devices be used in Phase I reopening of practice while devices that generate a visible plume such as Er:YAG laser resurfacing devices be avoided and only used with appropriate personal protective equipment in addition to a smoke evacuator in Phase IV reopening.

Oclusión de la vena safena con cianocrilato, una alternativa para el tratamiento de insuficiencia venosa crónica. Experiencia inicial en el Instituto Guatemalteco de Seguridad Social ­ IGSS / Occlusion of the saphenous vein with cyanoacrylate, an alternative for the treatment of chronic venous insufficiency. Initial experience at the Guatemalan Social Security Institute - IGSS

Las técnicas de termo ablación han revolucionado el tratamiento de la insuficiencia venosa crónica, siendo actualmente el estándar de tratamiento. Con el avance tecnológico han surgido nuevas técnicas quirúrgicas, no térmicas, no tumescentes; como el uso de cianocrilato para la oclusión venosa, el cual ha demostrado ser seguro y eficaz en el tratamiento, y tener menos complicaciones posoperatorias. Objetivo: Describir la experiencia en nuestro hospital con el uso de cianocrilato para la oclusión de vena safena mayor para el tratamiento de insuficiencia venosa crónica. Describir la eficacia a corto y mediano plazo del cierre, las complicaciones y la mejoría de la sintomatología utilizando el cuestionario CIVIQ-20 y EVA. Material y métodos: Estudio retrospectivo observacional. Entre enero y diciembre de 2019 que incluye a pacientes con insuficiencia de unión safeno femoral, sintomáticos. Con diagnóstico mediante clasificación CEAP y ultrasonido Doppler. Seguimiento clínico y ecográfico valorando oclusión de los segmentos tratados y presencia de venas varicosas a los 3 y 6 meses. Se trataron 5 pacientes con oclusión venosa con cianocrilato (100% mujeres). Valoramos la calidad de vida mediante cuestionario CIVIQ-20 y EVA (Escala Analógica Visual) previo y un mes después del procedimiento. También se describe la tasa de éxito y complicaciones inmediatas y tardías. Resultados: La totalidad de los procedimientos se realizaron con anestesia local, siendo bien tolerados. Con un éxito inmediato del 100 % sin necesidad de conversión. Solo se presentó como complicación urticaria en un paciente en el trayecto de la vena tratada con cianocrilato, la cual se trató con esteroides y resolvió. El CIVIQ-20 mostró mejoría global pasando de 35 a 29 puntos en promedio; siendo el parámetro de actividad física el que mostró una mejoría mayor. EVA demostró que la pesadez (principal síntoma) se redujo un 67%. Durante el seguimiento, ningún caso presento repermeabilización o recanalizaciones segmentarias. Conclusiones: El tratamiento endovenoso de la insuficiencia venosa crónica con las nuevas técnicas no térmicas, no tumescentes es seguro y efectivo. A corto-mediano plazo ofrecen resultados similares a las técnicas termoablativas obviando el inconveniente de la tumescencia y el uso de medias compresivas en el posoperatorio, evitando lesiones térmicas y observándose mejoría en la sintomatología. (AU)

Thermo ablation techniques have revolutionized the treatment of chronic venous insufficiency, being currently the standard of treatment. With technological advancement, new non-thermal, non-tumescent surgical techniques have emerged; such as the use of cyanoacrylate for venous occlusion, which has been shown to be safe and effective in treatment, and have fewer postoperative complications. Objective: To describe the experience in our hospital with the use of cyanoacrylate for occlusion of the greater saphenous vein for the treatment of chronic venous insufficiency. Describe the shortand medium-term efficacy of closure, complications, and symptom improvement using the CIVIQ-20 questionnaire and VAS. Material and methods: Retrospective observational study. Between January and December 2019 that includes patients with symptomatic saphenous femoral junction insufficiency. With diagnosis by CEAP classification and Doppler ultrasound. Clinical and ultrasound follow-up evaluating occlusion of the treated segments and the presence of varicose veins at 3 and 6 months. 5 patients with venous occlusion were treated with cyanoacrylate (100% women). We assessed the quality of life using the CIVIQ-20 questionnaire and VAS (Visual Analogue Scale) before and one month after the procedure. The immediate and late success rate and complications are also described. Results: All the procedures were performed under local anesthesia, being well tolerated. With immediate 100% success without the need for conversion. Urticaria only presented as a complication in a patient in the path of the vein treated with cyanoacrylate, which was treated with steroids and resolved. The CIVIQ-20 showed global improvement, going from 35 to 29 points on average; being the physical activity parameter the one that showed the greatest improvement. VAS showed that heaviness (main symptom) was reduced by 67%. During follow-up, no case presented segmental recanalization or recanalization. Conclusions: Endovenous treatment of chronic venous insufficiency with new non-thermal, non-tumescent techniques is safe and effective. In the short-medium term, they offer results similar to thermoablative techniques, avoiding the inconvenience of tumescence and the use of compression stockings in the postoperative period, avoiding thermal injuries and observing improvement in symptoms. (AU)

A Systematic Review of Nonsurgical Vulvovaginal Restoration Devices: An Evidence-Based Examination of Safety and Efficacy.

BACKGROUND: The efficacy and safety of vulvovaginal restoration devices were called into question in a U.S. Food and Drug Administration statement on July 30, 2018, claiming that women are being harmed by laser and other energy-based devices. The goal of this systematic literature review was to assess existing data, determine gaps in evidence, and propose opportunities for continued investigation pertaining to laser and energy-based vaginal restoration techniques. METHODS: A review of literature using PubMed, Cochrane Library databases, Embase, MEDLINE, and the Cumulative Index to Nursing and Allied Health Literature was conducted on January 9, 2019, and articles up to this point were considered. For inclusion, studies had to be available or translated in English and relate to clinical medicine, direct patient care, and nonsurgical energy-based vulvovaginal procedures. RESULTS: The authors found five level I studies, 19 level II studies, four level III studies, and 46 level IV studies that used 15 different devices. Various degrees of improvement of symptoms were reported in all studies. Adverse events/side effects were noted in two of the 13 radiofrequency device studies, 15 of the 23 erbium:yttrium-aluminum-garnet device studies, and 17 of the 37 carbon dioxide device studies. The majority of adverse events were considered mild. CONCLUSIONS: The majority of studies resulted in mild to no adverse side effects. However, there is a large gap in level I evidence. As a result, the authors emphasize the necessity of supplemental data surrounding this subject and suggest that additional randomized sham-controlled studies be conducted to further investigate vulvovaginal restoration devices in an effort to address women's health issues.

Monopolar Radiofrequency Energy Delivered by a Conductive Endovascular Basket or Guidewire Leads to Thermal Occlusion in a Swine Model.

PURPOSE: To assess the feasibility of inducing vascular occlusion by application of radiofrequency (RF) energy via conductive endovascular wires or baskets. MATERIALS AND METHODS: A retrievable nitinol basket and stainless steel guidewire with a platinum tip were evaluated as conductors for endovascular application of RF energy. Tissue-mimicking thermochromic gel phantoms that change color with heating were cast with 2-, 5-, and 7-mm-diameter lumens and filled with 37 oC saline. After ablation, the phantoms were sectioned, and the thermal footprints were evaluated. Six castrated male domestic swine underwent endovascular ablation using the basket in iliac arteries and guidewires in renal arteries. Post-procedural angiography was performed, and postmortem arterial segments were resected for histopathologic analysis. RESULTS: In the phantom, the depth of thermal change in the 5- and 7-mm lumens averaged 6.3 and 6.0 mm along the basket, respectively, and in the 2- and 5-mm lumens, the depth of thermal change averaged 1.9 and 0.5 mm along the wire, respectively. In the swine, RF energy delivery led to angiographic occlusion at 12 of 13 sites. Thermal injury and occlusion were similar at the proximal, middle, and distal basket treatment zone, whereas injury and occlusion decreased from the proximal to the distal end of the 5-cm wire treatment zone. CONCLUSIONS: Endovascular delivery of RF energy via a conductive basket in medium-sized arteries or a guidewire in small arteries led to acute angiographic and histologic occlusion. The potential to induce stasis might be useful in settings where rapid occlusion is desirable.

Endoscopic Ultrasound-Guided Antegrade Radiofrequency Ablation and Metal Stenting With Hepaticoenterostomy for Malignant Biliary Obstruction: A Prospective Preliminary Study.

OBJECTIVES: Endobiliary radiofrequency ablation (RFA) for malignant biliary obstruction is a promising option for improving biliary stent patency, but its efficacy and safety with endoscopic ultrasound (EUS)-guided biliary drainage are uncertain. We examined the feasibility of EUS-guided hepaticoenterostomy with antegrade stenting (EUS-HEAS) and RFA in patients with unresectable malignant biliary obstruction. METHODS: This was a prospective, single-center, single-arm, preliminary study. Twenty patients who met the eligibility criteria for inclusion between August 2018 and January 2020 were enrolled. We evaluated the technical success, functional success, recurrent biliary obstruction (RBO), and adverse events other than RBO associated with EUS-HEAS with RFA. RESULTS: The technical and functional success rates were both 80% (16/20). The procedure was unsuccessful in a total of 4 patients due to failure to insert the RFA catheter through the fistula (2 patients) or failure to pass the RFA catheter through the stricture (2 patients). Early and late adverse events other than RBO occurred in 10% (2/20) and 13% (2/16) of subjects, respectively. The RBO rate was 25% (4/16), and the median time to RBO was 276 days. The success rate of endoscopic reintervention using hepaticoenterostomy was 100% (4/4). DISCUSSION: This preliminary study showed that EUS-HEAS with RFA achieves good results but RFA catheter insertion can be difficult. Further evaluation and device improvements are warranted.

Radiofrequency ablation for DYT-28 dystonia: short term follow-up of three adult cases.

Mutations in the lysine methyltransferase 2B (KMT2B) gene have recently been reported to be associated with childhood-onset generalized dystonia. There have been no studies investigating ablative treatments for the management of this disorder. Three patients underwent either a staged unilateral pallidotomy and contralateral pallidothalamic tractotomy (19-year-old man, 2-year follow-up), a unilateral pallidothalamic tractotomy (34-year-old man, 6-month follow-up) or a simultaneous unilateral pallidothalamic tractotomy and ventro-oral thalamotomy (29-year-old man, 6-month follow-up). The average total patient score on the Burke-Fahn-Marsden Dystonia Rating Scale-Movement Scale improved from 39.5 to 13.2 (66.6%) after the procedures. No significant complications were identified. Ablative treatments appear to be a promising alternative surgical option for generalized dystonia with KMT2B mutation.

Ablación por radiofrecuencia en tumores óseos benignos / Radiofrequency Ablation in Benign Bone Tumors

CONTEXTO CLÍNICO: La incidencia de tumores óseos es de aproximadamente 1/100.000 habitantes/año para el sexo masculino y de 0,7 para el femenino a nivel mundial y generalmente se dan en personas menores de 30 años. La incidencia de los tumores benignos se estima que es mayor que la de tumores malignos, sin embargo, generalmente es probable que muchas veces se subestime ya que suelen ser asintomáticos y no diagnosticados; generalmente, son descubiertos de forma accidental mediante estudios radiográficos. Los tumores óseos benignos están formados por una amplia variedad de diferentes neoplasias. Dentro de los mas comunes, se pueden distinguir ocho tipos diferentes de tumores óseos que varían en incidencia, presentación clínica y posibles abordajes terapéuticos; osteocondroma, osteoma, osteoma osteoide, osteoblastoma, tumor de células gigantes, quiste óseo aneurismático, displasia fibrosa y encondroma. Los mismos pueden ser divididos en categorías en base al tipo de células que los forman; siendo entonces de estirpe ósea, cartilaginosa, de tejido conectivo y de tejido vascular. La mayoría de las veces el tratamiento es indicado solamente en los pacientes sintomáticos, siendo el dolor (por ejemplo, en los casos de osteoma osteoide y quiste óseo aneurismático) el síntoma más característico, o en los tumores con riesgo de fracturas patológicas o deformidad (como en el caso de el tumor de células gigantes y el encondroma). Cuando es necesario un abordaje, la cirugía; curetaje (raspado) y relleno mediante injerto óseo o escisión (extirpación mediante cirugía del tumor y parte del tejido normal que lo rodea) son los tratamientos habituales.2 Sin embargo, para algunos tumores óseos existen otras estrategias como la ablación, para la cual pueden usarse distintos métodos. La ablación percutánea guiada por imágenes es un tratamiento para distintos tumores primarios y secundarios dentro de los se encuentran algunos tumores óseos benignos. Dentro de los distintos tipos de ablación encontramos dos grandes divisiones, las ablaciones químicas(con químicos como etanol) y las ablaciones mediante energía, dentro de estas encontramos las técnicas de termablación.4 Si bien existen diversas técnicas de termoablación (laser, microondas, ultrasonido, etc.), la radiofrecuencia es la técnica de termoablación mas evaluada en tumores óseos benignos, y sobre todo en el osteoma osteide, aunque también puede ser utilizado en otros tumores benignos como el osteoblastoma, condroblastoma entre otros. La radiofrecuencia es una opción de tratamiento que presentaría una menor tasa de complicaciones y menor tiempo de rehabilitación post procedimiento. Sin embargo, esta técnica no permite realizar una biopsia luego del tratamiento por generar la destrucción de los tejidos. En este documento se evalúa la utilización de ablación por radiofrecuencia para el tratamiento de tumores óseos benignos. TECNOLOGÍA: La radiofrecuencia es una técnica de termoablación focal que se utiliza en tumores óseos tanto benignos como malignos. Es mínimamente invasiva dado que se puede aplicar de forma percutánea o por abordaje mínimo. Se realiza con el objeto de producir la muerte celular por necrosis por coagulación mediante calor.4 Esta constituido por sondas/cánulas y un generador de radiofrecuencia. Para su aplicación se requiere un equipo además del profesional que realice la intervención (profesionales de enfermería, radiólogo, anestesista, entre otros).4 Si bien no hay un requerimento formal de entrenamiento con radiofrecuencia, se recomienda que el profesional haya tenido la experiencia en un centro que preste el servicio previamente. Esta técnica usa un generador de 150 a 250 watts de frecuencia alterna que oscila entre el generador y el electrodo (cátodo) colocado en el tumor y el electrodo neutro (colocado en la superficie corporal).4 Cuando se utiliza un sistema bipolar no es necesaria la aplicación de un electrodo neutro debido a que el electrodo colocado en el tumor funciona tanto de cátodo como de ánodo. La corriente del circuito genera un proceso de fricción en la punta del electrodo creando calor (debido al efecto Joule) destruyendo así el tejido adyacente. La ablación tiene una extensión limitada debido a la deshidratación asociada en el tejido diana lo cual genera un aumento de la resistencia. Se pueden utilizar uno o más electrodos debido a la diferencia del tamaño del tumor, su ubicación y los diferentes tipos y diseños de los electrodos. A su vez, se suele colocar una sonda adicional para monitorear la temperatura del tejido durante la ablación. El procedimiento es realizado bajo sedación y anestesia local o regional o anestesia general. Una vez sedado el paciente, se debe guiar el procedimiento por tomografía computarizada (TC) o ressonância magnética (RM) para identificar el nido del tumor y la dimensión del mismo y así determinar el número e sondas necesarias y realizar una colocación correcta de las mismas. En casos de tumores óseos, la ablación por radiofrecuencia (ARF) esta indicada tanto como técnica curativa como paliativa. Dentro de las indicaciones curativas se encuentran tumores benignos (como el osteoma osteoide, osteoblasma, condroblastoma) o tumores óseos secundarios con contraindicación de cirugía (o pacientes que se nieguen a la cirugía).5 Sin embargo, se deben tener consideraciones especial en tumores intraarticulares, próximos a estructuras neurológicas, ubicados en la mano o en tumores cercanos a la placa de crecimiento. Dentro de las complicaciones más comunes se encuentran las lesiones de las estructuras adyacentes por la temperatura y las infecciones. Esta tecnología se encuentra aprobada por la Administración Nacional de Medicamentos, Alimentos y Tecnología (A.N.M.A.T.) y la Administración de Medicamentos y Alimentos (FDA por sus siglas en inglésFood and Drug Administration). OBJETIVO: El objetivo del presente informe es evaluar la evidencia disponible acerca de la eficacia, seguridad y aspectos relacionados a las políticas de cobertura del uso de radiofrecuencia para ablación de tumores óseos benignos. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas, en buscadores genéricos de internet, y financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias (ETS), evaluaciones económicas, guías de práctica clínica (GPC) y políticas de cobertura de diferentes sistemas de salud. RESULTADOS: Se incluyeron una RS, cuatro estudios observacionales, tres GPC, una evaluación económica, y diez informes de políticas de cobertura de radiofrecuencia para ablación de tumores óseos benignos. CONCLUSIONES: Evidencia de baja calidad proveniente de estudios observacionales sugiere que la ablación por radiofrecuencia podría ser efectiva para el tratamiento intervencionista de los tumores óseos benignos, y similar a la cirugía. A su vez, podría reducir el tiempo de internación y el tiempo de intervención requerida. Instituciones como la Sociedad de Radiología Cardiovascular e Intervencionista de Europa y el Colegio Real de Radiólogos del Reino Unido consideran la ablación por radiofrecuencia como una opción terapéutica inicial para el abordaje de tumores óseos benignos. La Sociedad de Radiología Intervencionista de Estados Unidos establece esta tecnología como el tratamiento de primera línea para osteomas osteoides, y como una alternativa para otros tumores óseos benignos. Agentes financiadores públicos de Brasil y el Reino Unido; y financiadores privados de EE.UU. cubren esta tecnología para el tratamiento de osteoma osteoide. No se encontraron en la región estúdios que evalúen la costo-efectividad de esta tecnología en las indicaciones evaluadas.