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Aims: The purpose of this study was to assess the effectiveness of a navigational radiofrequency ablation device with concurrent vertebral augmentation in the treatment of posterior vertebral body metastatic lesions, which are technically difficult to access. Primary outcomes of the study were evaluation of pain palliation and radiologic assessment of local tumor control. Materials and Methods: Thirty-five patients with 41 vertebral spinal metastases involving the posterior vertebral body underwent computed tomography-guided percutaneous targeted radiofrequency ablation, with a navigational radiofrequency ablation device, associated with vertebral augmentation. Twenty-one patients (60%) had 1 or 2 metastatic lesions (Group A) and fourteen (40%) patients had multiple (&gt, 2) vertebral lesions (Group B). Changes in pain severity were evaluated by visual analog scale (VAS). Metastatic lesions were evaluated in terms of radiological local control. Results: The procedure was technically successful in all the treated vertebrae. Among the symptomatic patients, the mean VAS score dropped from 5.7 (95% CI 4.9–6.5) before tRFA and to 0.9 (95% CI 0.4–1.3) after tRFA (p &lt, 0.001). The mean decrease in VAS score between baseline and one week follow up was 4.8 (95% CI 4.2–5.4). VAS decrease over time between one week and one year following radiofrequency ablation was similar, suggesting that pain relief was immediate and durable. Neither patients with 1–2 vertebral metastases, nor those with multiple lesions, showed radiological signs of local progression or recurrence of the tumor in the index vertebrae during a median follow up of 19 months (4–46 months) and 10 months (4–37 months), respectively. Conclusion: Treatment of spinal metastases with a navigational radiofrequency ablation device and vertebral augmentation can be used to obtain local tumor control with immediate and durable pain relief, providing effective treatment in the multimodality management of difficult-to-reach spinal metastases.

Radiofrequency ablation (RFA) is a clinically established therapy for hepatocellular carcinoma (HCC). However, because of poor radio-thermal conductivity of liver tissues, RFA is less efficient against relatively larger (>5 cm) liver tumors. Recently, nanoparticle-enabled RFA has emerged as a better strategy. On the basis of our recent understanding on biodegradability and novel electrothermal properties of graphene, herein, we report development of transferrin conjugated, biodegradable graphene (TfG) for RFA therapy. Cellular uptake studies using confocal microscopy and Raman imaging revealed significantly higher TfG uptake by HCC cells compared to bare graphene. TfG-treated cancer cells upon 5 min exposure to 100 W, 13.5 MHz RF showed >85% cell death, which was 4 times greater than bare graphene. Further evaluation in 3D (3 Dimensional) HCC culture system as well as in vivo rat models demonstrated uniform destruction of tumor cells throughout the 3D microenvironment. This study reveals the potential of ...

Radiofrequency ablation (RFA) is a clinically established therapy for hepatocellular carcinoma (HCC). However, because of poor radio-thermal conductivity of liver tissues, RFA is less efficient against relatively larger (5 cm) liver tumors. Recently, nanoparticle-enabled RFA has emerged as a better strategy. On the basis of our recent understanding on biodegradability and novel electrothermal properties of graphene, herein, we report development of transferrin conjugated, biodegradable graphene (TfG) for RFA therapy. Cellular uptake studies using confocal microscopy and Raman imaging revealed significantly higher TfG uptake by HCC cells compared to bare graphene. TfG-treated cancer cells upon 5 min exposure to 100 W, 13.5 MHz RF showed85% cell death, which was 4 times greater than bare graphene. Further evaluation in 3D (3 Dimensional) HCC culture system as well as in vivo rat models demonstrated uniform destruction of tumor cells throughout the 3D microenvironment. This study reveals the potential of molecularly targeted graphene for augmented RFA therapy of liver tumor.

Radiofrequency ablation (RFA) and percutaneous vertebroplasty (PVP) are used independently and in combination to treat metastatically involved vertebrae with the aim of relieving pain, reducing tumour burden and providing bony mechanical stabilization. The aim of this work was to characterize the effect of two bone-targeted RFA devices, alone and in combination with PVP, to improve strength and mechanical stability in vertebrae with osteolytic metastatic disease. Simulated spinal metastases (n = 12) were treated with one of two bone-targeted RFA devices (bipolar cooled or bone coil RF electrodes), followed by PVP. Under axial compressive loading, spinal canal narrowing was measured in the intact specimen, after tumour simulation, post-RFA and post-PVP. RFA alone resulted in successful tumour shrinkage and cavitation, but further increased canal narrowing under loading. RFA combined with PVP significantly reduced posterior wall stability in samples where sufficient tumour shrinkage and cavitation were coupled with a pattern of cement deposition which extended to posterior vertebral body. RFA combined with cement deposition in the posterior vertebral body demonstrates significantly more stable vertebrae under axial loading.

BackgroundTreatment of spinal metastatic lesions by radiofrequency ablation (RFA) before cementation can potentially help in local tumor control and pain relief. This is often limited by access and tumor location. This study reports multicenter clinical and imaging outcomes following targeted RFA (t-RFA) and cement augmentation in neoplastic lesions of the spine.Material and methodsA retrospective multicenter study of 49 patients with 72 painful vertebral lesions, evaluated for clinical and imaging outcomes following RFA and cement augmentation of spinal metastatic lesions, was undertaken. Visual Analogue Pain score (VAS) and Oswestry Disability Index (ODI) were obtained before and 2–4 weeks after treatment. Pre- and post-procedure imaging examinations including MRI and positron emission tomography (PET) were also evaluated.ResultsMean ablation time was 3.7±2.5 min (range 0.92–15). Mean VAS scores decreased from 7.9±2.5 pre-procedure to 3.5±2.6 post-procedure (pConclusionst-RFA followed by vertebral augmentation in malignant vertebral lesions resulted in significant pain reduction and functional status improvement, with no major complications. t-RFA permitted access to vertebral lesions and real-time accurate monitoring of the ablation zone temperature. Post-procedure MRI and PET examinations correlated with a favorable tumor response and helped to monitor tumor growth and the timing of adjuvant therapy.

Objectives This study sought to develop an actively tracked cardiac magnetic resonance-guided electrophysiology (CMR-EP) system and perform first-in-human clinical ablation procedures. Background CMR-EP offers high-resolution anatomy, arrhythmia substrate, and ablation lesion visualization in the absence of ionizing radiation. Implementation of active tracking, where catheter position is continuously transmitted in a manner analogous to electroanatomic mapping (EAM), is crucial for CMR-EP to take the step from theoretical technology to practical clinical tool. Methods The setup integrated a clinical 1.5-T scanner, an EP recording and ablation system, and a real-time image guidance platform with components undergoing ex vivo validation. The full system was assessed using a preclinical study (5 pigs), including mapping and ablation with histological validation. For the clinical study, 10 human subjects with typical atrial flutter (age 62 ± 15 years) underwent MR-guided cavotricuspid isthmus (CTI) ablation. Results The components of the CMR-EP system were safe (magnetically induced torque, radiofrequency heating) and effective in the CMR environment (location precision). Targeted radiofrequency ablation was performed in all animals and 9 (90%) humans. Seven patients had CTI ablation completed using CMR guidance alone; 2 patients required completion under fluoroscopy, with 2 late flutter recurrences. Acute and chronic CMR imaging demonstrated efficacious lesion formation, verified with histology in animals. Anatomic shape of the CTI was an independent predictor of procedural success. Conclusions CMR-EP using active catheter tracking is safe and feasible. The CMR-EP setup provides an effective workflow and has the potential to change the way in which ablation procedures may be performed.

IntroductionSacral metastases and myelomatous lesions often result in debilitating pain and significant morbidity in patients with prolonged life expectancy. Radiation therapy and cement augmentati...

Purpose: The two most common methods for treating symptomatic vertebral body compression fractures are percutaneous vertebroplasty (PV) and kyphoplasty (KP). Controversy exists as to the optimal treatment method. However, there is no controversy as to the disparity with higher costs of KP over PV. Previous reports have failed to demonstrate efficacy of PV. This has lead to one major regional health insurance provider in our area to deny reimbursement for PV while continuing to approve KP. Here we review our experiences with PV and KP since the mandated implementation of KP by the insurance provider. Materials and Methods: Patients who presented with symptomatic compression fractures and MRI or spinal CT and nuclear medicine bone scan evidence of acute/subacute spinal compression fracture underwent percutaneous spinal interventions at our institution from December 1, 2012, through July 31, 2014, and were included in this retrospective analysis. KP was perfromed on some patients as required by their insurance provider. Baseline demographics, type of intervention, level treated, complications, outcomes, and repeat interventions were systematically reviewed. Results: During the study time period, 120 [93(78%) VP and 27 (22%) KP] patients underwent 198 [155(78%) VP and 43(22%) KP] procedures. There were no differences in baseline characteristics. Outcomes were similar in each group with no reported major adverse events. VAS pain scale was not statistically different between the two groups [pre 8.8 and 9.0 in KP and VP (p1⁄40.7); post 4.7 and 4.3 in KP and VP (p1⁄40.4)]. Longer rates of fluoroscopy time associated with KP was statistically significant [6.5 and 4.7 min in KP vs VP (P o0.001)]. Average Medicare reimbursement for a surgical center performing thoracic vertebroplasty in our area was approximately $2,100, while thoracic kyphoplasty was approximately $6,900. Conclusion: Although outcomes are similar between percutaneous vertebroplasty and kyphoplasty, kyphoplasty is associated with significantly higher rates of radiation exposure and drastically higher healthcare costs.

at 1 month in 26/39 (67%), unchanged in 6/39 (15%), and decreased in 7/39 (18%) of patients. 30 patients had imaging follow up with 60% demonstrating local tumor control, and select cases showing retraction of posterior tumor with epidural extension. Most RFAs were followed by vertebral augmentation for lesions with or at risk of pathological fractures. Conclusion: Targeted RFA is a safe and effective method of treating spinal metastases resistant to RT with significantly improved pain and functional scores.

Purpose Report initial clinical experience and determine the efficacy and safety of targeted radiofrequency ablation (t-RFA) of malignant spinal lesions using a novel bipolar RF ablation system. Demonstrate the use of temperature monitoring of thermocouples (TC) on an articulating electrode to determine ablation size and morphology with use of post-ablation magnetic resonance imaging (MRI) and comparison with pre-clinical thermal distribution curves. Materials and Methods 101 spinal lesions in 73 procedures were treated at six centers. The STAR Tumor Ablation System includes a robust articulating, navigational bipolar electrode containing two active TCs positioned to permit real time monitoring of the peripheral edge of the ablation zone to determine size of ablation. Treatment was controlled by adjusting power while monitoring TC temperature in-situ. Access and number of ablations were based on lesion size, location and ability to articulate the bipolar electrode. Cement augmentation via the same guiding cannula was performed when required. In some cases, post-procedural MRI was performed. Pain was assessed pre- and postprocedurally. Results Lesion etiology included a wide variety of metastatic lesions from T2 to S2 and ilium. No complications or thermal injury occurred. Cement augmentation following t-RFA was efficient and resulted in predictable cement filling. Postablation MRIs demonstrated discrete ablation zones with 3:2 length-to-width aspect ratio consistent in size with thermal monitoring by TCs during the ablation. All patients reported pain relief. Conclusion The STAR device was safely and effectively used in the navigation and t-RFA of spinal malignant lesions. Postablation MRIs confirmed lesions were included in the ablation zone with necrosis of the lesion. The ablation zone was consistent in size with that measured by the TCs and similar in morphology to that extrapolated from thermal distribution curves. The STAR navigational ability allowed for easy access to posterior vertebral body lesions, previously difficult to access with other ablation devices. In many cases, this technique allowed for treatment of individual lesions not controlled by systemic or radiation therapy.

Purpose: We are reporting early clinical outcome of t-RFA followed by cement augmentation in painful malignant lesions of the spine using a novel bipolar RF ablation system, purpose built for minimally invasive procedures in the axial skeleton. Materials and Methods: 51 spinal lytic lesions in 34 patients with different malignant etiologies were included after IRB approval. Primary diagnosis includes; myeloma (n1⁄411), breast cancer (n1⁄49), lung cancer (n1⁄46), lymphomas (n1⁄45) and pancreatic (n1⁄41), renal (n1⁄41) and neuroendocrine tumor (n-1). The STAR Tumor Ablation System is a bipolar device that contain two thermocouples (TC) positioned at 10 and 20 mm from center of the ablation zone to permit real-time monitoring of the ablation zone. RF warmed cement augmentation via the same guiding cannula was performed after lesion ablation. Results: All procedures were performed safely with no complications or thermal injury. Ablation time ranged from 1.5-6 minutes. Maximum recorded temperature was 651C at the distal TC and 501C at the proximal TC (10 and 20 mm from the center of the ablation zone, respectively). TCs on the electrode were used to confirm re-establishment of core temperature prior to cement augmentation. Post procedure CT showed no significant cement leakage. Average VAS scores dropped from 7.8 pre-procedure to 3.6, 2-4 weeks post-procedure. Average ODQ scores improved from 26.5 to 15.7, 2-4 weeks postprocedure. Decreased tumor volume and decreased metabolic activity was confirmed by MRI and PET scan, respectively. Conclusion: Targeted RF Ablation followed by RF warmed high viscosity cement augmentation was performed successfully in this series of malignant spinal lesions. Improvement in pain and functional status was noted in all patients. The articulating ability of the STAR Tumor Ablation System permitted minimally invasive access to all lesions, regardless of location. Proximal and distal TCs allowed accurate monitoring of the temperature inside the vertebral body to avoid complications of nearby vital structures. Targeted delivery of high viscosity cement following ablation via the same guiding cannula provided vertebral stability.

10585 Background: Metastatic spinal lesions can be debilitating with significant impact on patients quality of life. Concern for damage to adjacent neural elements during treatment exist due to high radiation doses required to treat certain radioresistant spinal lesions such as soft tissue sarcoma. Radiofrequency ablation (RFA) of metastatic lesions has been shown to be effective in bone. Spine anatomy presents challenges for minimally invasive (MI) treatment of posterior vertebral body lesions. Targeted RFA (t-RFA) using a novel tumor ablation system, designed for spinal anatomy is evaluated in patients with symptomatic posterior vertebral wall spinal lesions. Methods: Five patients with metastatic leiomyosarcoma or liposarcoma and posterior vertebral body spine lesions, treated by prior radiation with continued progression of lesion size and pain received t-RFA, using a novel spinal tumor ablation system (STAR, DFINE), which contains an articulating bipolar, extensible electrode for navigation. Device thermocouples (TC) permit real time monitoring of the ablation zones to determine size. Sequential post-procedural pain scores, PET and contrast enhanced magnetic resonance imaging, and histopathology of treated area was performed. Results: No complications or thermal injury occurred. Intra-procedural imaging demonstrated the articulated, bipolar instrument was able to navigate to posterior lesions. Post-ablation MRI demonstrated lesion necrosis within a discrete ablation zone. No evidence of malignancy by PET or histopathology was noted through 10 months. All patients reported post procedural pain relief. Systemic therapy was not interrupted. Conclusions: Navigational t-RFA proved a safe and effective, non-ionizing palliative therapy alternative for radio-resistant lesions . Post-ablation imaging and histology confirmed metastatic lesions were necrotic and included in ablation zone with tumor control 10 mos post treatment. Ablation zone was very consistent with real time temperature readings. t-RFA permitted MI targeted treatment of lesions within close proximity of spinal cord, not controlled by systemic therapy. Prospective clinical trial is under preparation.