Diffusion‐weighted MRI monitoring of pancreatic cancer response to radiofrequency heat‐enhanced intratumor chemotherapy

The aim of this study was to evaluate the feasibility of using diffusion‐weighted MRI to monitor the early response of pancreatic cancers to radiofrequency heat (RFH)‐enhanced chemotherapy. Human pancreatic carcinoma cells (PANC‐1) in different groups and 24 mice with pancreatic cancer xenografts in four groups were treated with phosphate‐buffered saline (PBS) as a control, RFH at 42 °C, gemcitabine and gemcitabine plus RFH at 42 °C. One day before and 1, 7 and 14 days after treatment, diffusion‐weighted MRI and T₂‐weighted imaging were applied to monitor the apparent diffusion coefficients (ADCs) of tumors and tumor growth. MRI findings were correlated with the results of tumor apoptosis analysis. In the in vitro experiments, the quantitative viability assay showed lower relative cell viabilities for treatment with gemcitabine plus RFH at 42 °C relative to treatment with RFH only and gemcitabine only (37 ± 5% versus 65 ± 4% and 58 ± 8%, respectively, p < 0.05). In the in vivo experiments, the combination therapy resulted in smaller relative tumor volumes than RFH only and chemotherapy only (0.82 ± 0.17 versus 2.23 ± 0.90 and 1.64 ± 0.44, respectively, p = 0.003). In vivo, 14‐T MRI demonstrated a remarkable decrease in ADCs at day 1 and increased ADCs at days 7 and 14 in the combination therapy group. The apoptosis index in the combination therapy group was significantly higher than those in the chemotherapy‐only, RFH‐only and PBS treatment groups (37 ± 6% versus 20 ± 5%, 8 ± 2% and 3 ± 1%, respectively, p < 0.05). This study confirms that it is feasible to use MRI to monitor RFH‐enhanced chemotherapy in pancreatic cancers, which may present new options for the efficient treatment of pancreatic malignancies using MRI/RFH‐integrated local chemotherapy. Copyright © 2013 John Wiley & Sons, Ltd.     

Irreversible Electroporation of a Hepatocellular Carcinoma Lesion Adjacent to a Transjugular Intrahepatic Portosystemic Shunt Stent Graft

We report in a 65-year-old man hepatocellular carcinoma adjacent to a transjugular intrahepatic portosystemic shunt stent-graft which was successfully treated with irreversible electroporation (IRE). IRE is a new non-thermal tissue ablation technique which uses electrical pulses to induce cell necrosis by irreversible membrane poration. IRE proved to be more advantageous in the ablation of perivascular tumor with little injury to the surrounding structures.     

Resolution of retracted scar after 585-nm pulse dye laser surgery

BACKGROUND: Laser scar revision has been an effective method for improving several aspects of scarring through ablative and non-ablative sources. The 585-nm pulsed dye laser (PDL) is an important non-ablative instrument for reducing scar bulk and symptoms. OBJECTIVE: To describe the use of a 585-nm PDL for the treatment of a retracted and atrophic facial scar. METHODS: We report the case of a 26-year-old patient who presented with a retracted facial scar following surgical excision of an aggressive benign tumor. Treatment was carried out using the 585-nm PDL. RESULTS: Treatment of the scar using two low-level PDL therapies significantly altered the appearance of the scar and augmentation of the retracted defect was avoided. CONCLUSION: Treatment of this retracted and atrophic facial scar with the 585-nm PDL was very effective and safe.     

GI and Hepatology 2008: Advances and Case Discussions

Mayo Clinic recently presented an outstanding education meeting in Orlando, FL, USA. This meeting is one of several education meetings coordinated by the gastroenterology and hepatology divisions from Mayo Clinic held throughout the year in multiple locations in the USA. The focus of this 3-day meeting was to provide an update on advances in all areas of gastroenterology with an emphasis on the management of difficult cases. A total of 23 podium presentations, 17 breakout sessions and a Fellow’s poster program were presented. In addition, there was a specific program directed at nurses involved in the care of gastroenterology patients. Highlights from selected presentations are included in this report.     

A low‐cost,mechanically simple apparatus for measuring eddy current‐induced magnetic fields in MRI

The fidelity of gradient waveforms in MRI pulse sequences is essential to the acquisition of images and spectra with minimal distortion artefacts. Gradient waveforms can become nonideal when eddy currents are created in nearby conducting structures; however, the resultant magnetic fields can be characterised and compensated for by measuring the spatial and temporal field response following a gradient impulse. This can be accomplished using a grid of radiofrequency (RF) coils. The RF coils must adhere to strict performance requirements: they must achieve a high sensitivity and signal‐to‐noise ratio (SNR), have minimal susceptibility field gradients between the sample and surrounding material interfaces and be highly decoupled from each other. In this study, an apparatus is presented that accomplishes these tasks with a low‐cost, mechanically simple solution. The coil system consists of six transmit/receive RF coils immersed in a high‐molarity saline solution. The sensitivity and SNR following an excitation pulse are sufficiently high to allow accurate phase measurements during free‐induction decays; the intrinsic susceptibility matching of the materials, because of the unique design of the coil system, results in sufficiently narrow spectral line widths (mean of 19 Hz), and adjacent RF coils are highly decoupled (mean S₁₂ of ?47 dB). The temporal and spatial distributions of eddy currents following a gradient pulse are measured to validate the efficacy of the design, and the resultant amplitudes and time constants required for zeroth‐ and first‐order compensation are provided. Copyright © 2013 John Wiley & Sons, Ltd.     

Progress in studies on pathological changes and future treatment strategies of obesity-associated female stress urinary incontinence: a narrative review

With the increasing prevalence of obesity worldwide, obesity-related female stress urinary incontinence (FSUI) has become a key health problem. Recent studies indicated that FSUI is primarily caused by obesity-related pathological changes, such as fat droplet deposition, and results in pelvic floor nerve, vascular, and urethral striated muscle injury. Meanwhile, treatments for obesity-associated FSUI (OA-FSUI) have garnered much attention. Although existing OA-FSUI management strategies, including weight loss, pelvic floor muscle exercise, and urethral sling operation, could play a role in symptomatic relief; they cannot reverse the pathological changes in OA-FSUI. The continued exploration of safe and reliable treatments has led to regenerative therapy becoming a particularly promising area of researches. Specifically, micro-energy, such as low-intensity pulsed ultrasound (LIPUS), low-intensity extracorporeal shock wave therapy (Li-ESWT), and pulsed electromagnetic field (PEMF), have been shown to restore the underlying pathological changes of OA-FSUI, which might be related by regulation endogenous stem cells (ESCs) to restore urine control function ultimately in animal experiments. Therefore, ESCs may be a target for repairing pathological changes of OA-FSUI. The aim of this review was to summarize the OA-FSUI-related pathogenesis, current treatments, and to discuss potential therapeutic options. In particular, this review is focused on the effects and related mechanisms of micro-energy therapy for OA-FSUI to provide a reference for future basically and clinical researches.     

Radiofrequency-induced thermotherapy (RFiTT) in a porcine liver model and ex vivo great saphenous vein

Aims: To investigate the thermal spread achieved in porcine liver when using an optimised radiofrequency ablation protocol and correlate findings with the effects seen in ex vivo great saphenous vein (GSV), in order to justify clinical use with the new treatment protocol.

Material and methods: Porcine liver and GSV sections were treated with radiofrequency-induced thermotherapy (RFiTT) using the following settings: 20 W at 1?s/cm (linear endovenous energy density; LEED 20 J/cm), 18 W at 1?s/cm (LEED 18 J/cm), 18 W at 3?s/cm (LEED 54 J/cm), 6 W interrupted pull-back 6?s stationary every 0.5?cm (LEED 72 J/cm). Thermal spread in the liver was measured via digital imaging. GSV sections were sent to an independent laboratory for histological analysis. Previous work suggests a thermal spread of?>0.65?mm in liver correlates with transmural thermoablation of a GSV.

Results: Parameters giving a LEED of 72 J/cm produced the best results, with a clear transmural effect in the GSV and maximal thermal spread of 1.65?mm, without excessive thermal damage or carbonisation in the ablation tract.

Conclusions: Our porcine liver model correlated well with histological findings and was representative of the thermoablative effects observed in the GSV wall treated with RFiTT. Clinical investigations are now being carried out to investigate the efficacy of this protocol in the clinical setting.     

Metastatic parathyroid carcinoma treated with radiofrequency ablation: A novel therapeutic modality

Parathyroid carcinoma (PCA), accounting for less than one per cent of all endocrine malignancies, is a rare cause of primary hyperparathyroidism. A diagnosis of parathyroid carcinoma may be challenging in the presence of localised disease and involves a histological diagnosis based on capsular, vascular, or perineural invasion or the presence of metastasis. Distant metastasis remains a rare presentation, with the lung being the most common site. Surgery remains the treatment of choice as radiotherapy and chemotherapy have proved to be of limited benefit in metastatic disease. This case reports suggests that radiofrequency ablation has the potential to be a novel and effective treatment option in these patients.     

房颤射频消融术术后AF早期复发的预测因素

房颤(AF)是临床上最常见的一种心律失常。AF射频消融术作为一种非药物治疗AF的手段正被广泛利用,但术后AF的复发率较高。早期有研究显示,高龄、超重和肥胖、病程、左房内径、左房疤痕和纤维化等为预测AF消融术术后AF复发的相关因素。最新研究显示,阻塞性睡眠呼吸暂停综合征、伴有慢性肾脏疾病、4q25等位基因多态性等对AF早期复发的预测具有一定的意义。     

射频热凝与伽玛刀治疗原发性三叉神经痛的疗效比较

 目的 比较立体定向射频热凝术与立体定向放射技术(伽玛刀)治疗原发性三叉神经痛的疗效。方法 回顾性分析2014-01至2016-01收治的46例原发性三叉神经痛患者临床资料,其中立体定向射频热凝术21例(射频组),伽玛刀治疗25例(伽玛刀组)。对比两组治疗后疼痛控制率、并发症和复发情况,评定疗效。结果 46例随访时间12～36个月,平均25.6个月。根据巴罗(BNI)疼痛量表评定,射频组术后Ⅰ级17例(81.0%),Ⅱ级2例(9.5%),Ⅲ级1例(4.8%),Ⅳ～Ⅴ级1例(4.8%),有效Ⅰ～Ⅲ级20例(95.2%);伽玛刀组术后Ⅰ级12例(48.0%),Ⅱ级4例(16.0%),Ⅲ级6例(24.0%),Ⅳ～Ⅴ级3例(12.0%),有效Ⅰ～Ⅲ级22例(88.0%)。术后两组比较,射频组Ⅰ级优于伽玛刀治疗组,差异有统计学意义(P＜0.05),Ⅱ、Ⅲ级及有效率差异无统计学意义。术后射频组面部麻木发生率(81.0%)明显高于伽玛刀组(9.5%),咀嚼肌力下降、口角流涎、角膜炎发生率等两组对比,差异无统计学意义。射频组、伽玛刀组复发各1例。结论 射频热凝和伽玛刀治疗三叉神经痛疗效肯定,射频治疗起效快,恢复优良率高,但有一定的侵袭性和并发症;伽玛刀治疗无创,并发症少且轻,相对更安全,缺点是起效较慢。