Percutaneous radiofrequency ablation of HCC: reduced ablation duration and increased ablation size using single, internally cooled electrodes with an optimized pulsing algorithm

Purpose To assess the use of optimized radiofrequency (RF) to achieve larger, spherical ablation volumes with short application duration for hepatocellular carcinoma (HCC). Materials and methods Twenty-two patients (M:F = 17:5, median age 69.6 year, range 63–88) with 28 HCCs due to HCV + liver cirrhosis underwent RFA. 20/28 (71.4%) were tumors ≤3cm diameter, and 8/28 (28.6%) ranged from 3.2 to 4.2 cm. RF was applied using up to 2500mA via an optimized pulsing algorithm with real-time ultrasound monitoring to detect hyperechogenic changes. Single insertions of an internally cooled electrode were performed using exposed tips of 2 or 3 cm for 13 HCCs and 4 cm for 15 HCCs. All patients were followed-up for a minimum of 5 years with contrast-enhanced computed tomography (CECT). Results Technical success was achieved without adverse events in all cases. The mean ablation time was 8.5 ± 2.6 min. In 21/28 (75%), ablation duration ranged from 3 to 9 min, with 12 min duration applied in only 7/28 (25%). Mean coagulation diameters were 2.4 ± 0.14, 3.3 ± 0.62, and 4.4 ± 1.0, for 2, 3 and 4 cm electrodes, respectively (p 3 cm tumors developed local progression. One patient had multifocal disease with no local progression. Conclusion Efficient delivery of RF energy can considerably decrease the ablation time in many instances while achieving larger, relatively spherical, and reproducible areas of ablation with extremely low rates of local tumor progression and adverse events

Ultrastructural Changes in Axons Following Exposure to Pulsed Radiofrequency Fields

Pulsed radiofrequency (PRF) fields applied by an electrode to neural structures, such as the peripheral sensory nociceptor axons and dorsal root ganglion, are clinically effective in reducing pain and other neuropathic syndromes. However, a full understanding of the underlying mechanisms by which this occurs has not yet been clarified. In this study, PRF is applied to the afferent axons of the sciatic nerves of rats. A standard radiofrequency (RF) electrode and RF generator is used to apply the RF signal output to the sciatic nerve using standard PRF parameters that have been successfully used in clinical practice. The ultrastructure of the treated axons is observed after 10 days by electron microscopy. A control, sham application is simultaneously applied to the contralateral sciatic nerve to provide a statistical differential comparison. It is found that the internal ultrastructural components of the axons show microscopic damage after PRF exposure, including: abnormal membranes and morphology of mitochondria, and disruption and disorganization of microfilaments and microtubules. The damage appears to be more pronounced for C-fibers than for A-delta and A-beta fibers. The results are discussed in terms of internal electric field strengths and thermodynamic parameters

Romosozumab Followed by Antiresorptive Treatment Increases the Probability of Achieving Bone Mineral Density Treatment Goals

Increases in bone mineral density (BMD) with osteoporosis treatment are associated with reduced fracture risk. Increasing BMD is therefore a goal of osteoporosis therapy. Here, we compare the probability of achieving a T-score of > -2.5 over 3 years at the total hip (TH) or lumbar spine (LS) in women with osteoporosis, ≥55 years of age, after the following treatment sequences: 1 year romosozumab followed by 2 years denosumab (FRAME and FRAME extension trials), 1 year romosozumab followed by 2 years alendronate, or alendronate-only for 3 years (ARCH trial). Probabilities of attaining the BMD target within 1 year of treatment were also determined. At both skeletal sites, in women with a baseline Tscore ≥ -2.7, there was >50% probability of achieving the BMD target with any 3-year regimen. The probability of achieving the target BMD in those with a baseline TH Tscore equal to -3.0 was 61% with romosozumab/denosumab, 38% with romosozumab/alendronate, and 9% with alendronate. In those with a baseline LS Tscore equal to -3.0, the probability of achieving a T-score > -2.5 was 93% with romosozumab/denosumab, 81% with romosozumab/alendronate, and 55% with alendronate. With 1 year of treatment, in patients with a baseline TH T-score equal to -2.7, the probability of reaching the target Tscore with romosozumab was 71% to 78% and 38% with alendronate. For patients with an initial LS T-score equal to -3.0, the probability of achieving the target T-score over 1 year was 85% to 86% with romosozumab and 25% for alendronate. Our findings suggest baseline BMD and the probability of achieving BMD T-score goals are factors to consider when selecting initial treatment for patients with osteoporosis. As baseline T-score falls below -2.7 (TH) and -3.0 (LS), alendronate has <50% likelihood of achieving a BMD goal above osteoporosis range, whereas these probabilities remain relatively high for regimens beginning with romosozumab. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research

T-Score as an Indicator of Fracture Risk During Treatment With Romosozumab or Alendronate in the ARCH Trial

In the Active-Controlled Fracture Study in Postmenopausal Women With Osteoporosis at High Risk (ARCH) clinical trial (NCT01631214), 1 year of romosozumab followed by alendronate reduced the risk of vertebral and nonvertebral fractures compared to alendronate alone in women with prevalent fracture. We performed post hoc analyses of data from patients in ARCH (romosozumab, n = 1739; alendronate, n = 1726) who had a baseline BMD measurement and received at least one open-label alendronate dose. We evaluated 1-year mean BMD and corresponding T-score changes; proportions of patients achieving T-scores > -2.5 at the total hip (TH), femoral neck (FN), and lumbar spine (LS); and group differences in fracture rates after 12 months, while all participants were on alendronate.[...