Radiofrequency Thermal Effects on the Human Meniscus: An in Vitro Study of Systems with Monopolar and Bipolar Electrodes

2003 ◽  
Vol 31 (2) ◽  
pp. 253-256 ◽  
Author(s):  
C. Thomas Vangsness ◽  
John D. Polousky ◽  
Andrew B. Parkinson ◽  
Thomas P. Hedman
Keyword(s):  
Thermal Effects ◽  
Thermal Damage ◽  
Energy Output ◽  
Radiofrequency Energy ◽  
Bipolar Electrodes ◽  
Application Systems ◽  
Meniscal Tissue ◽  
Individual System ◽  
Energy Application ◽  
The Individual

Background: No data exist on the cutting efficiency of monopolar versus bipolar radiofrequency energy application systems on human meniscal tissue. Purpose: To compare the effects of monopolar and bipolar thermal energy systems on human meniscal tissue. Study Design: Controlled laboratory study. Methods: Fresh-frozen menisci were cut in cross-section into 180 pie-shaped specimens. A specially designed jig was used to consistently apply radiofrequency energy to the tissue under a constant 30-g force. Three different systems were tested at the low, middle, and high ranges, with application times of 1 and 3 seconds. Thermal effects were measured by image analysis microscopy. Results: No significant differences in thermal effects were found with respect to energy output for each system. Both the individual system tested and the application time had statistically significant effects on thermal damage, with the individual system tested having a greater effect. The mean depths of thermal change produced by the Mitek (bipolar) device were 564 and 648 μm at 1 and 3 seconds applications, respectively. The Arthrocare device (bipolar) produced depths of 1444 and 1697 μm at 1 and 3 seconds. The Oratec device (monopolar) produced depths of 895 and 1057 μm, respectively. Conclusions: A differential thermal effect was created in the meniscal tissue by three commercially available radiofrequency systems. Within the parameters of the experiment, all three systems limited thermal damage to a depth of less than 2 mm. The results appeared to depend more on the particular system used, not whether it had monopolar or bipolar electrodes. Clinical Relevance: These data imply reasonably safe (less than 2 mm) thermal changes in the meniscus after radiofrequency energy application from these three systems.

Colorants in plastic applications

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Gerhard Pfaff
Keyword(s):  
Current Knowledge ◽  
Review Article ◽  
Important Application ◽  
Processing Method ◽  
Application Systems ◽  
Plastic Type ◽  
Printing Inks ◽  
Cosmetic Formulations ◽  
Plastics Processing ◽  
The Individual

AbstractThis review article is a summary of the current knowledge in the field of plastic coloring. Plastics belong as well as paints, coatings, printing inks, and cosmetic formulations to the most important application systems for colorants, both for pigments and dyes. Colorants have to meet increasing demands in plastic applications due to the growing number of polymers with specific properties. Crucial factors besides the plastic type are the processing method and the required fastness level. Among the most important polymers for coloring with pigments and dyes are polyolefins, polyvinyl chloride, polyurethane, polyamide, polycarbonate, polyester, and elastomers. Different processing methods are used for coloring of the individual plastics. The coloring processes need to be coordinated in accordance with the steps of the plastics processing leading to the final product.

scholarly journals Community Global Observing System Simulation Experiment (OSSE) Package (CGOP): Assessment and Validation of the OSSE System Using an OSSE–OSE Intercomparison of Summary Assessment Metrics

2018 ◽  
Vol 35 (10) ◽  
pp. 2061-2078 ◽  
Author(s):  
Sid-Ahmed Boukabara ◽  
Kayo Ide ◽  
Yan Zhou ◽  
Narges Shahroudi ◽  
Ross N. Hoffman ◽  
...  
Keyword(s):  
System Simulation ◽  
Weather Prediction ◽  
Real Data ◽  
New Techniques ◽  
Forecast Performance ◽  
Individual System ◽  
Assessment Metrics ◽  
The Individual ◽  
The Tropics ◽  
Observing System Simulation Experiment

AbstractObserving system simulation experiments (OSSEs) are used to simulate and assess the impacts of new observing systems planned for the future or the impacts of adopting new techniques for exploiting data or for forecasting. This study focuses on the impacts of satellite data on global numerical weather prediction (NWP) systems. Since OSSEs are based on simulations of nature and observations, reliable results require that the OSSE system be validated. This validation involves cycles of assessment and calibration of the individual system components, as well as the complete system, with the end goal of reproducing the behavior of real-data observing system experiments (OSEs). This study investigates the accuracy of the calibration of an OSSE system—here, the Community Global OSSE Package (CGOP) system—before any explicit tuning has been performed by performing an intercomparison of the OSSE summary assessment metrics (SAMs) with those obtained from parallel real-data OSEs. The main conclusion reached in this study is that, based on the SAMs, the CGOP is able to reproduce aspects of the analysis and forecast performance of parallel OSEs despite the simplifications employed in the OSSEs. This conclusion holds even when the SAMs are stratified by various subsets (the tropics only, temperature only, etc.).

scholarly journals Efficacy of Pulsed Radiofrequency in the Treatment of Thoracic Postherpetic Neuralgia from the Angulus Costae: A Randomized, Double-Blinded, Controlled Trial

2013 ◽  
Vol 1;16 (1;1) ◽  
pp. 15-25
Author(s):  
Wang Yingwei
Keyword(s):  
Side Effects ◽  
Postherpetic Neuralgia ◽  
Sham Group ◽  
Bodily Pain ◽  
Energy Output ◽  
Radiofrequency Energy ◽  
Pulsed Radiofrequency ◽  
Number Of Patients ◽  
Sf 36 ◽  
Double Blinded

Background: Postherpetic neuralgia (PHN) is often refractory to existing treatments. Pulsed radiofrequency (PRF) is known to be effective for treating neuropathic pain. In common, the targets of PRF treatment were the segmental dorsal root ganglion (DRG) neurons responsible for the pain. A potential complication that can occasionally occur with PRF treatment is damage to the adjacent tissue and organ. The effectiveness of the angulus costae as a puncture site for PRF has not been tested in thoracic PHN treatment. Objective: The goal of this study was to investigate the therapeutic efficacy and safety of PRF for treating thoracic PHN through the puncture of the angulus costae. Study Design: Prospective, randomized, double-blinded study. Setting: Department of Anesthesiology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine. Methods: Ninety-six patients with thoracic (T2-11) PHN were equally randomized assigned into 2 groups. The electrode needle punctured through the angulus costae of each patient guided by x-ray; PRF at 42°C for 120 seconds was applied after inducing paresthesia involving the affected dermatome area. PRF was applied in the PRF group (n = 48) twice. It was also applied in the sham group (n = 48) twice without radiofrequency energy output. The treatment was done once a week for 3 weeks. Tramadol was used for flare pain when the visual analog scale (VAS) ≥ 3. Outcomes Assessment: The therapeutic effect was evaluated by VAS, SF-36 health survey questionnaire, side effects (type, frequency, and onset time) before treatment, at days 3, 7, and 14, and at months one, 2, 3 and 6 after PRF. The average of tramadol (mg/d) administrated within the first month after treatment was also recorded. Results: The postprocedure VAS scores in the PRF group were significantly lower than those in the sham group and lasted for 6 months after treatment (P < 0.05). The SF-36 score, such as physical functioning, physical role, bodily pain, general health perceptions, social function, emotional role, and mental health index were significantly improved until 6 months after treatment in the PRF group compared to the sham group (P < 0.01-0.05). The average dosage of tramadol administered (mg/d) within the first month after treatment was also significantly reduced in the PRF group compared to the sham group (P < 0.05). There were no obvious signs of pneumothorax, bleeding, infection, or other severe side effects in either group (P > 0.05). Limitations: Single center study, relatively small number of patients. Conclusions: The strategy that the angulus costae be used as the PRF puncture point of an electrode needle and the final localization of the needle tip as determined by sensory testing is an effective and safe therapeutic alternative for thoracic PHN treatment. Benefits include that the procedure is minimally invasive, provides short-term pain relief, and improves quality of life. Clinical Trial Registration: NO ISRCTN25588650. Key words: Thoracic, postherpetic neuralgia, pulsed radiofrequency, angulus costae

scholarly journals Thermal Analysis of Cornea Heated with Terahertz Radiation

2019 ◽  
Vol 9 (5) ◽  
pp. 917
Author(s):  
Wenquan Liu ◽  
Yuanfu Lu ◽  
Rongbin She ◽  
Guanglu Wei ◽  
Guohua Jiao ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Analysis ◽  
Terahertz Radiation ◽  
Thermal Effects ◽  
Thermal Damage ◽  
Treatment Approach ◽  
Thz Radiation ◽  
Beam Radius ◽  
Corneal Tissue ◽  
Temperature Distributions

We numerically investigate the thermal effects in a cornea illuminated by terahertz radiation. By modifying the bioheat and Arrhenius equations, we studied the heat-transfer and temperature distributions in the corneal tissue, and evaluated the potential thermal damage. The influence of the beam radius and power density are discussed. We also estimated the effective cornea-collagen shrinkage region, and evaluated the degree of thermal damage in the cornea. We expect this work to open up a novel effective and safe thermal-treatment approach based on THz radiation for cornea reshaping in the field of ophthalmology.

An Increase in Sinus Rate Following Radiofrequency Energy Application in the Posteroseptal Space

1998 ◽  
Vol 21 (1) ◽  
pp. 303-307 ◽  
Author(s):  
CHRISTOPH GELLER ◽  
ANDREAS GOETTE ◽  
MARK D. CARLSON ◽  
HANS DIETER ESPERER ◽  
WOLFGANG M. HARTUNG ◽  
...  
Keyword(s):  
Radiofrequency Energy ◽  
Sinus Rate ◽  
Energy Application

scholarly journals The Individual System in Winnetka

1920 ◽  
Vol 21 (1) ◽  
pp. 52-68 ◽  
Author(s):  
Carleton W. Washburne
Keyword(s):  
Individual System ◽  
The Individual
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