No abstract available.
Dermatitis, Contact ; Hyperthermia, Induced

No abstract available.
Breast* ; Fever* ; Hyperthermia, Induced ; Leiomyosarcoma*

Cholangiocarcinoma is a highly malignant tumor. It is not sensitive to radiotherapy and chemotherapy and has a poor prognosis. At present, there is no effective treatment. As a new method for treating cancer, magnetic fluid hyperthermia has been clinically applied to a variety of cancers in recent years. This article introduces it to the cholangiocarcinoma model and systematically studies the effect of magnetic fluid hyperthermia on cholangiocarcinoma. Starting from the theory of magnetic fluid heating, the electromagnetic and heat transfer models were constructed in the finite element simulation software COMSOL using the Pennes biological heat transfer equation. The Helmholtz coil was used as an alternating magnetic field generating device. The relationship between the magnetic fluid-related properties and the heating power was analyzed according to Rosensweig's theory. After the multiphysics coupling simulation was performed, the electromagnetic field and thermal field distribution in the hyperthermia region were obtained. The results showed that the magnetic field distribution in the treatment area was uniform, and the thermal field distribution met the requirements of hyperthermia. After the magnetic fluid injection, the cholangiocarcinoma tissue warmed up rapidly, and the temperature of tumor tissues could reach above 42 °C, but the surrounding healthy tissues did not heat up significantly. At the same time, it was verified that the large blood vessels around the bile duct, the overflow of the magnetic fluid, and the eddy current heat had little effect on thermotherapy. The results of this article can provide a reference for the clinical application of magnetic fluid hyperthermia for cholangiocarcinoma.
Cholangiocarcinoma ; Humans ; Hyperthermia ; Hyperthermia, Induced ; Magnetic Fields ; Magnetics

A new 2450MHz invasive antenna for microwave hyperthermia is designed in this paper. The finite element method is employed to simulate the choke antenna and improved choke antenna, i.e., choke-umbrella antenna. The specific absorption rates (SAR) in tumors are calculated with the two kinds of antennas. S11 of choke-umbrella antenna is also compared with that of choke antenna. Multi-layered block of tissue-equivalent phantom is heated with the fabricated invasive antenna. The distribution of the temperature field in the invasive layer as well as the three-dimensional distribution of the temperature field in phantom is obtained with an infrared thermo graphic technique. Research results show that the improved choke-umbrella antenna can generate more uniform temperature distribution and meets the requirements of the actual clinical microwave hyperthermia better.
Equipment Design ; Hyperthermia, Induced ; instrumentation ; Microwaves

Visualization of the tissue loss tangent property can provide distinct contrast and offer new information related to tissue electrical properties. A method for non-invasive imaging of the electrical loss tangent of tissue using magnetic resonance imaging (MRI) was demonstrated, and the effect of loss tangent was observed through simulations assuming a hyperthermia procedure. For measurement of tissue loss tangent, radiofrequency field maps (B1+ complex map) were acquired using a double-angle actual flip angle imaging MRI sequence. The conductivity and permittivity were estimated from the complex valued B1+ map using Helmholtz equations. Phantom and ex-vivo experiments were then performed. Electromagnetic simulations of hyperthermia were carried out for observation of temperature elevation with respect to loss tangent. Non-invasive imaging of tissue loss tangent via complex valued B1+ mapping using MRI was successfully conducted. Simulation results indicated that loss tangent is a dominant factor in temperature elevation in the high frequency range during hyperthermia. Knowledge of the tissue loss tangent value can be a useful marker for thermotherapy applications.
Fever ; Hyperthermia, Induced ; Magnetic Resonance Imaging ; Magnets

Cell Differentiation ; Humans ; Hyperthermia, Induced ; Stem Cells

PURPOSE: The purpose of this study was to determine the influence of various factors on the extent of thermal coagulation necrosis after radiofrequency (RF) tissue ablation using a cooled-tip electrode in bovine liver. MATERIALS AND METHODS: RF ablation was induced by a monopolar 500 KHz-RF generator (CC-1; Radionics,Burlington, Mass., U.S.A.) and an 18-G cooled-tip with single or clustered electrodes. The ablation protocol involveda combination of varying current, ablation time, power output, gradual or abrupt increase of this out-put, and pulsed radiofrequency techniques. The maximum diameter of all thermal lesions which showed a color change was measured perpendicular to the electrode axis by two observers who reached their decisions by consensus. Twenty representative lesions were pathologically examined. RESULTS: With increasing current lesion diameter also increased, but above 1500 mA no further increase was induced. Extending the ablation time to 9 minutes for a single electrode and 15 minutes for a clustered electrode increased lesion diameter until a steady state was reached. Higher power levels caused larger lesions, but above 100 W no increase was observed. Ample exposure time coupled with a stepwise increase in power level induced a lesion larger than that resulting from an abrupt increase. Continuous pulsed RF with a high current led to increased coagulation necrosis diameter. CONCLUSION: These experimental findings may be useful thermotherapy. The data suggest that all involved factors significantly affect lesion size: if the factors are better understood, cancer thermotherapy can be better controlled.
Animals ; Axis, Cervical Vertebra ; Consensus ; Electrodes ; Hyperthermia, Induced ; Liver* ; Necrosis

PURPOSE: We attempt to compare the impact of transurethral microwave thermotherapy (TUMT) with alpha-1 blocker (terazosin) on the symptom score, flow rate and residual urine. MATERIALS AND METHOD: A total of 29 patients underwent TUMT and 20 patients were treated by terazosin. FDA symptom score, urinary flow rate and residual urine before and after therapy were analyzed. RESULTS: Although an improvement in symptom score, flow rate and residual urine was noted at 6 months in both groups, there was no statistic significance between two groups in symptom score and flow rate. Reduction of residual urine only showed marginally significant difference in two groups. CONCLUSION: Except patients with absolute indications for transurethral resection of the prostate (TURP), those with symptomatic benign prostatic hyperplasia (BPH) will be benefited by these two modalities and TUMT is more effective than alpha-1 blocker in reducing residual urine.
Humans ; Hyperthermia, Induced ; Microwaves ; Prostate ; Prostatic Hyperplasia* ; Transurethral Resection of Prostate*

OBJECTIVETo study the influence of thermochemotherapy on the activity of cytotoxic T lymphocyte (CTL) in peripheral blood of patients with oral maxillofacial cancer.

METHODSTwenty-one subjects with oral maxillofacial cancer were treated by thermochemotherapy, and the activity of CTL in peripheral blood was analyzed.

RESULTSThermochemotherapy can obviously enhance the activity of CTL (P<0.01).

CONCLUSIONThermochemotherapy can enhance the activity of CTL, thus enhance the patient's immune function. Therefore, it can enhance the antitumor response in whole body.

A safety protection method which can be used on perfusion hyperthermia Instrument. The method is based on temperature sensor, weighing sensor, and programming and featured with safe and simple, easy to achieve, fault detection, quick response.
Equipment Design ; Equipment Safety ; Hyperthermia, Induced ; adverse effects ; instrumentation