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Radiofrequency Device (radiofrequency + device)
Selected AbstractsRadiofrequency ablation partial nephrectomy: A new method of nephron-sparing surgery in selected patientsINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2006MAREK SALAGIERSKI Abstract, From July 2002 to April 2005, seven radiofrequency ablation partial nephrectomies have been carried out in seven selected patients. A cool-tip Tyco radiofrequency device under intraoperative ultrasound guidance was used. After intervention, tumors were removed and their tissue with their margins were verified histopathologically. Procedure efficacy was assessed by multidetector computed tomography and by ultrasound. Complications included urine leakage in three cases. Histopathologically, in every case renal cell carcinoma was detected. There is no need for dialysis and there has been no tumor recurrence. No bleeding without clamping renal pedicle, easy tumor extraction and, we hope, reduced risk of recurrence are the major advantages of this intervention. [source] Modified radiofrequency-assisted liver resection: A new deviceJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2007Dimitris Zacharoulis MD Abstract Background Radiofrequency ablation (RF) is emerging as new therapeutic method for the management of hepatic tumors. So far the RF-assisted hepatectomy has been described using an electrode initially designed for ablation of unresectable tumors. Herein, we describe a new technique for liver resection using a bipolar radiofrequency device. Method Ten patients undergo liver resection using a bipolar radiofrequency device. A minimal zone of desiccation around the tumor is created between pairs of opposing electrodes as a result of a minimum amount of energy released. This coagulated plane can be divided with a scalpel. Results The liver parenchyma was divided with minimal blood loss. No intensive care unit admission was needed. There was no postoperative biliary leak or any other septic complication. Conclusion The technique is safe and feasible, simplifies liver resection and appears to be associated with minimal morbidity and maximum liver parenchyma preservation. J. Surg. Oncol. 2007;96: 254,257. © 2007 Wiley-Liss, Inc. [source] Circumference reduction and cellulite treatment with a TriPollar radiofrequency device: a pilot studyJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 7 2009W Manuskiatti Abstract Background, A wide variety of treatments for circumference reduction and cellulite are available, but most procedures offer suboptimal clinical effect and/or delayed therapeutic outcome. Objective, To determine the safety and efficacy of the TriPollar radiofrequency device for cellulite treatment and circumference reduction. Methods, Thirty-nine females with cellulite received eight weekly TriPollar treatments. Treatment areas included the abdomen, thighs, buttocks and arms. Subjects were evaluated using standardized photographs and measurements of body weight, circumference, subcutaneous thickness, and skin elasticity of the treatment sites at baseline, immediately after and 4 weeks after the final treatment. Physicians' evaluation of clinical improvement scores using a quartile grading scale was recorded. Results, Thirty-seven patients (95%) completed the treatment protocol. There was significant circumference reduction of 3.5 and 1.7 cm at the abdomen (P = 0.002) and thigh (P = 0.002) regions, respectively. At 4 weeks after the last treatment, the average circumferential reductions of the abdomen and thighs were sustained. No significant circumferential reductions of the buttocks and arms at the last treatment visit compared to baseline were demonstrated (P = 0.138 and 0.152, respectively). Quartile grading scores correlating to approximately 50% improvement in cellulite appearance were noted. Conclusions, Tripollar radiofrequency provided beneficial effects on the reduction of abdomen and thigh circumference and cellulite appearance. Conflict of Interest The authors have no financial interest in this article. [source] Hyperthermic injury to adipocyte cells by selective heating of subcutaneous fat with a novel radiofrequency device: Feasibility studiesLASERS IN SURGERY AND MEDICINE, Issue 5 2010Walfre Franco PhD Abstract Background and Objective The main objective of the present study is to demonstrate the feasibility of utilizing a novel non-invasive radiofrequency (RF) device to induce lethal thermal damage to subcutaneous adipose tissue only by establishing a controlled electric field that heats up fat preferentially. Study Design/Materials and Methods Adipocyte cells in six-well plates were subjected to hyperthermic conditions: 45, 50, 55, 60, and 65°C during 1, 2, and 3,minutes. Cell viability was assessed 72,hours after exposure. Two groups of abdominoplasty patients were treated with the RF device during and days before their surgical procedure. Temperatures of cutaneous and subcutaneous tissues were measured during treatment (3,minutes) of the first group. The immediate tissue response to heating was assessed by acute histology. The delayed tissue response was assessed by histology analysis of the second group, 4, 9, 10, 17, and 24 days after treatment (22,minutes). A mathematical model was used to estimate treatment temperatures of the second group. The model uses patient-based diagnostic measurements as input and was validated with in vivo clinical temperature measurements. Results Cell viability dropped from 89% to 20% when temperature increased from 45 to 50°C during 1,minute exposures. Three minutes at 45°C resulted in 40% viability. In vivo, the temperature of adipose tissue at 7,12,mm depth from the surface increased to 50°C while the temperature of cutaneous tissues was <30°C during RF exposure. Acute and longitudinal histology evaluations show normal epidermal and dermal layers. Subcutaneous tissues were also normal acutely. Subcutaneous vascular alterations, starting at day 4, and fat necrosis, starting at day 9, were consistently observed within 4.5,19,mm depth from the skin surface. Subcutaneous tissue temperatures were estimated to be 43,45°C for 15,minutes. Conclusions A controlled internal electric field perpendicular to the skin,fat interface is selective in heating up fat and, consequently, has the ability to induce lethal thermal damage to subcutaneous adipose tissues while sparing overlying and underlying tissues. In vitro adipocyte cells are heat sensitive to thermal exposures of 50 and 45°C on the order of minutes, 1 and 3,minutes, respectively. In vivo, 15,minutes thermal exposures to 43,45°C result in a delayed adipocyte cellular death response,in this study, 9 days. The novel RF device presented herein effectively delivers therapeutic thermal exposures to subcutaneous adipose tissues while protecting epidermal and dermal layers. Lasers Surg. Med. 42:361,370, 2010. © 2010 Wiley,Liss, Inc. [source] Pilot clinical study of a novel minimally invasive bipolar microneedle radiofrequency device,LASERS IN SURGERY AND MEDICINE, Issue 2 2009Basil M. Hantash MD Abstract Background and Objectives Noninvasive bipolar and monopolar radiofrequency (RF) deep dermal heating devices have previously been described. A novel minimally invasive RF device employing a bipolar microneedle electrode system is introduced and its resultant thermal effects on human skin in vivo were characterized for the first time. Study Design/Materials and Methods An investigational 35 W RF device was configured to operate in bipolar mode delivering energy directly within the dermis using 5 microneedle electrode pairs with real-time feedback of tissue temperature for treatment control. Superficial cooling was achieved using a Peltier device. A range of pulse durations between 1 and 25 seconds, and lesion temperatures between 60 and 80°C were tested in vivo on 15 human subjects. Thermal effects were assessed histologically using either hematoxylin & eosin (H&E) or nitroblue-tetrazoliumchloride (NBTC) staining. Treatment effects and adverse events were also monitored clinically. Results The investigational bipolar RF device delivered controlled heating within dermal tissue. Histological staining with H&E revealed the presence of zones of denatured collagen within the reticular dermis. Lesions were generated at preselected temperatures between 60 and 80°C. Fractional lesions separated by zones of sparing as well as contiguous lesion patterns were demonstrated. Histological staining with H&E and NBTC revealed sparing of adnexal structures and adipose tissue. No major adverse events were observed. Conclusions A novel fractional RF device utilizing a minimally invasive bipolar microneedle delivery system for the treatment of human tissue was developed. Treatment of 15 human subjects illustrated the controlled creation of dermally located thermal coagulation zones, herein known as radiofrequency thermal zones. We discovered that varying the pulse length allowed for fractional sparing of dermal tissue. To our knowledge, this is the first report to describe use of a direct real-time temperature and impedance feedback system to control energy delivery during deep dermal heating. Lasers Surg. Med. 41:87,95, 2009. © 2009 Wiley-Liss, Inc. [source] A prospective, split face, single-blinded study looking at the use of an infrared device with contact cooling in the treatment of skin laxity in asiansLASERS IN SURGERY AND MEDICINE, Issue 2 2008FRCP, Henry H. Chan MBBS Abstract Background Although monopolar radiofrequency treatment is effective in the improvement of skin laxity, the pain and cost that are associated with this method suggest the need for alternative treatment options. Recently, an infrared device with contact cooling has been shown to be effective in the treatment of skin laxity, with ultrastructural changes observed that are similar to those that are observed following treatment with a monopolar radiofrequency device. However, no control was included in previous studies. Objective To conduct a prospective, split-face, single-blinded study to look at the efficacy and complications among Asians of treatment for skin tightening with an infrared device with contact cooling. Method Thirteen Chinese women were treated. An infrared device with contact cooling (Titan, Cutera, Brisbane, CA) was used to treat one side of the face and the untreated side served as the control. The treatment was performed twice with a 4-week interval between the treatments and the patients were followed up by subjective assessment using a structured questionnaire 1 and 3 months after the second (and last) treatment. In all cases, pre- and post-treatment clinical photographs were taken. Two independent observers assessed the photographs. Results Twenty-three percentage of patients reported mild improvement, 15% reported moderate improvement, and 54% reported significant improvement 3 months after their second (and last) treatment. In terms of objective assessment, 41% of patients were identified to have some degree of improvement of the treated side 3 months after their second treatment. Compared with the untreated side, the treated side improved significantly (P,=,0.031) at 1 and 3 months after the second treatment. Blistering occurred in one patient, which had resolved completely by the 3-month follow-up visit. Conclusion An infrared device with contact cooling can be used effectively and safely for the treatment of skin laxity, especially in smaller anatomical areas. Lesers Surg. Med. 40:146,152, 2008. © 2008 Wiley-Liss, Inc. [source] Nonablative Laser Surgery for Pigmented SkinDERMATOLOGIC SURGERY, Issue 10 2005David J. Goldberg MD Background. Nonablative laser surgery has been proven to improve early photodamaged skin and acne scars. These techniques include treatments with lasers, light sources, and/or radiofrequency devices. Objectives. To review the history of nonablative technology and its applicability to darker skin types and to provide an objective look at the various published studies documenting the efficacy of nonablative technology. Conclusion. Nonablative laser surgery can improve skin quality and acne scars in all skin types. Complications are rare but can occur. Future studies are required to compare the efficacy of the various nonablative technologies. DAVID J. GOLDBERG, MD, HAS INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Current techniques of liver transectionHPB, Issue 3 2007RONNIE T.P. POON The operative mortality rate of liver resection has decreased from 10% to 20% before the 1980s to <5% in most specialized hepatobiliary centers nowadays. The most important factor for better outcome is reduced blood loss due to improvement in surgical techniques. Liver transection is the most challenging part of liver resection, associated with a risk of massive hemorrhage. Understanding the segmental anatomy of the liver and delineation of the proper transection plane using intraoperative ultrasound are prerequisites to safe liver transection. Clamp crushing and ultrasonic dissection are the two most widely used transection techniques. In recent years, new instruments using different types of energy for coagulation or sealing of vessels have been developed for liver transection. These include radiofrequency devices, Harmonic Scalpel, Ligasure and TissueLink dissecting sealer. Whether these new instruments, used alone or in combination with clamp crushing or ultrasonic dissection, improve the safety of liver transection has not been clearly demonstrated. The use of the vascular stapler for transection of major intrahepatic vascular trunks is also gaining popularity. These new instruments are particularly useful in liver transection during laparoscopic liver resection. Adjunctive measures such as intermittent Pringle maneuver and low central venous pressure anesthesia are also useful measures to reduce the risk of hemorrhage. This article reviews the safety and efficacy of different techniques of liver transection, with particular attention to evidence from randomized controlled trials available in the literature. [source] | ||||||||||