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

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

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

Cell Differentiation ; Humans ; Hyperthermia, Induced ; Stem Cells

PURPOSE: Recently, many alternative forms of non-surgical treatment modalities were devised for the management of BPH and one of them is transurethral radiofrequency thermotherapy(TURT). In this study, we investigated the long term efficacy of TURT. MATERIALS AND METHOD: A total of 132 patients with symptomatic BPH were treated in a single session with TURT using Thermex-ll(47.5 degrees C, 150minutes) and 88 patients who were available to follow-up for more than 6 months after TURT were enrolled in this study. Among them, 65 patients were available to follow-up for more than 2 years. The baseline and post-treatment mean symptom score(Madson-Iversen), maximal flow rate(MFR), residual urine volume and prostate volume were compared. Improvement was defined as a reduction of more than 50% in at least one of two parameters(symptom score and maximal flow rate). We also investigated whether other treatment modalities were selected in 2 years after TURT. RESULTS: At 3 months follow-up, improvements were observed in 59.1%(52/88), and at 6 months 54.5%(48/88). However, improvements in both symptom score and maximal flow rate at 3 and 6 months after treatment were only 27.3% and 20.5%, respectively. Among 65 patients who were available to follow-up for more than 2 years, 27 patients(41.5%) had undergone transurethral resection of the prostate either with(19) or without medication(8). 28 patients (43.1%) received medical therapy such as alpha blocker during the last two years after TURT. The post-treatment values of the 10 patients who had not received adjuvant therapy were not significantly different from those at baseline. CONCLUSIONS: Although thermal treatment for BPH is an alternative option with minimal complication in selected symptomatic patients who are not clear candidates for surgery or high-risk patients, the long term effect of TURT is not sufficient to relieve the obstructive and irritative symptoms of BPH.
Follow-Up Studies ; Humans ; Hyperthermia, Induced* ; Prostate ; Prostatic Hyperplasia*

PURPOSE: we clinically measured the temperature rise in real time and analyzed the difference of albino rabbit and pigmented rabbit in use of the specially designed thermometer. METHODS: Specially designed thermometer was attached into the subretinal pigment epithealial and choroidal space through the suprachoroidal space in three pigment and three albino rabbits, with diode laser of 810 nm wave length, 3 mm spot size. We examined the retinal temperature according to laser irradiance power at each ten seconds during sixty seconds and the laser power setting was 200 mW, 300 mW, 400 mW in pigmeted rabbit and 300 mW, 600 mW, 800 mW in albino rabbit. We analyzed the results based on the measurements at least three times per each irradiance power. RESULTS: In albino rabbit, the maximal range of retinal temperature change was 1.2 degrees C and 1.7 degrees C in 300 mW and 600 mW, 14.1 degrees C in 800 mW power of 810 nm diode laser irradiance. In pigmented rabbit, the maximal range of retinal temperature change was 12.1 degrees C in 200 mW of laser irradiance power, 16.2 degrees C in 300 mW, 24.3 degrees C in 400 mW during sixty seconds in 810 nm diode laser. CONCLUSIONS: We investigated the ratinal temperature at transpupillary thermotherapy in 810 nm wavelength diode laser on rabbits. The difference of retinal temperature change was in accordance with the amount of chorioretinal melanin pigment. Therefore if the laser power setting used in caucasians would be attempted in orientals, it is the point to be considered during transpupillary thermotherapy.
Choroid ; Hyperthermia, Induced* ; Lasers, Semiconductor ; Melanins ; Rabbits* ; Retinaldehyde* ; Thermometers

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*

We noticed the treatment results of each of them after having treated the seventy-nine cases of benign prostatic hyperplasia with TUMT (N=32, Term ; 92.6-93.3), TUR-P (N=31, Term; 91.4-93.3), open prostatectomy (N=16, Term; 91.4-93.3). However, there was a difficulty to get to statistical reliability, for there was a little gap between the term of survey and the period of treatment of three groups. The results are following. In the TUMT, the maximal flow rate was improved from 8.2ml/s to 13.3ml/s and Madsen score dropped from 13.6 to 5.3, in the TUR-P they were 8.4ml/s to 16.5ml /s and 14.5 to 5.3 respectively, and in the open prostatectomy 6.8ml/s to 20.0ml/s and 15.8 to 5. 3 respectively. The degree of satisfaction of the patients themselves with each prescription was 46.9% in the TUMT. 67.7% in the TUR-P and 81.2% in the open prostatectomy. But 18.8% and l6.l% of the patients thought TUMT and TUR-P respectively ineffective. The conclusion is that open prostatectomy presented the better results than TUMT or TUR-P in the degree of satisfaction of patients and uroflowmetry during the survey period. And even though TUMT have presented lesser degree of satisfaction then TUR-P up to now, if the exact indications for the use of TUMT are found and the mechanical improvements undergo, then a number of benign prostatic hyperplasia cases seem to be treated in more safety and with lesser cost and time by TUMT instead of TUR-P.
Humans ; Hyperthermia, Induced ; Microwaves* ; Prescriptions ; Prostatectomy* ; Prostatic Hyperplasia*