• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.1
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• pp.109-114
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• 1997

Malignant hyperthermia is a hypermetabolic, fatal syndrome triggered by anesthetic drugs that occurs frequently in genetically susceptible persons. It is characterized by tachycardia, rapidly increasing temperature, skeletal muscle rigidity, respiratory and metabolic acidosis, cyanosis etc. It has been noted that the majority of cases of malignant hyperthermia are fatal unless early diagnosis and treatment are performed. Thus, the accurate prediction of preanesthetic susceptibility and early diagnosis of malignant hyperthermia is necessary to appropriate treatment. Dantrolene sodium has been shown to be effective in the prevention and treatment of malignant hyperthermia. We experienced a case of malignant hyperthermia, which is presented of a 32-year-old healthy male patient in whom a orthognatic surgery was performed under $O_2-N_2O$-enfl-rane anesthesia with induction by pentobarbital and succinylcholine. We discuss this case with reviewing the history, incidence, etiology, pathophysiology, clinical signs & biochemical changes, prevention & treatment.

• Radiation Oncology Journal
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• v.34 no.1
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• pp.34-44
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• 2016

Purpose: A prospective phase II trial was conducted to evaluate the effectiveness and toxicity of regional hyperthermia and whole liver irradiation (WLI) for numerous chemorefractory liver metastases from colorectal cancer. Materials and Methods: Enrolled patients had numerous chemorefractory hepatic metastases from colorectal cancer. Five sessions of hyperthermia and seven fractions of 3-gray WLI were planned. Health-related quality of life (HRQoL) was determined using the Korean version of the European Organization for Research and Treatment of Cancer quality of life questionnaire C-30 and the Functional Assessment of Cancer Therapy-Hepatobiliary version 4.0. Objective and pain response was evaluated. Results: A total of 12 patients consented to the study and the 10 who received WLI and hyperthermia were analyzed. WLI was completed as planned in nine patients and hyperthermia in eight. Pain response was partial in four patients and stable in four. Partial objective response was achieved in three patients (30.0%) and stable disease was seen in four patients at the 1-month follow-up. One patient died 1 month after treatment because of respiratory failure related to pleural metastasis progression. Other grade III or higher toxicities were detected in three patients; however, all severe toxicities were related to disease progression rather than treatment. No significant difference in HRQoL was noted at the time of assessment for patients who were available for questionnaires. Conclusion: Combined WLI and hyperthermia were well tolerated without severe treatment-related toxicity with a promising response from numerous chemorefractory hepatic metastases from colorectal cancer.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1744-1753
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• 2016

The main purpose of this article is a complex hyperthermia applicator system design for treatment of head and neck region. The applicator system is composed of four waveguides with a stripline horn aperture and circular water bolus. The specific absorption rate (SAR) and temperature distribution from this applicator in various numerical phantom models was investigated. For used targets, the treatment planning based on the optimization process made through the SEMCAD X software is added to show the steering possibilities of SAR and thereby temperature distribution. Using treatment planning software, we proved that the SAR and temperature distribution can be effectively controlled (by amplitude and phase changing) improving the SAR and temperature target coverage approximately by 20 %. For the proposed applicator system analysis and quantitative evaluation of two parameters 25 % iso-SAR and $41^{\circ}C$ iso-temperature contours in the treatment area with the respect to sensitive structures in treatment area were defined. To verify our simulation results, the real measurement of reflectivity coefficient as well as the temperature distribution in a homogenous phantom were performed.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.53-53
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• 2003

For evaluating the feasibility of treating recurrent lesions in the vaginal cuff and cervix by hyperthermia, ultrasound applicators were designed, constructed, and characterized. For the treatment A half-cylindrical transducer Cd=1cm, length=lcm) and cylindrical transducer (d=2.5cm, length= 1.5cm) were used to construct ovoid type and cylindrical applicators. For the ovoid type applicator, each element was operated at 1.5MHz and characterized by measuring transducer efficiency and acoustic power distribution. Thermocouple probes were used to measure the temperature rise in phantom. The element sizes used in this study were selected to be comparable for high dose rate brachytherapy colpostat applicator. Each element was powered separately to achieve a desired temperature pattern in a target. The acoustic output power as a function of applied electric power of the element 1 and 2 was linear over this 1 to 40 W range and efficiencies were 32.2${\pm}$3.4% and 46.2${\pm}$0.8%, respectively. The temperature measurements in phantom showed that 6$^{\circ}C$ temperature rise was achieved at 2 cm from the applicator surface. As a conclusion, the ability of the ultrasound colpostat applicator to be used for hyperthermia was demonstrated by measuring acoustic output power, ultrasound field distribution, and temperature rise in phantom. Based on the characteristics of this applicator, it has the potential to be useful for inducing hyperthermnia to the vaginal cuff in clinic.

• Korean Journal of Head & Neck Oncology
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• v.6 no.1
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• pp.40-45
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• 1990

Thirty five lesions of 35 patients with locally advanced malignant tumors of head and neck were received thermoradiotherapy with ultrasound and/or 915 MHz microwave. Most of all patients were failed with previous conventional therapeutic trial. Hyperthermia had been done immediately after radiotherapy, twice a week, $43^{\circ}C$ for one hour and radiotherapy had been done 5 fractions per week with a fraction size of 2 Gy up to total 30 to 60 Gy. Conclusions are as follows; 1) Total response rate (CR+PR) of thermoradiotherapy with microwave and ultrasound was 80%. 2) Tumor depth, minimum temperature of tumor center, number of heat fraction and irradiation dose were statistically significant factors affecting response. 3) Hyperthermia with microwave and ultrasound can be used efficiently to control locally advanced malignant tumors in head and neck whether previously received near tolerance dose of radiotherapy or not.

• Investigative Magnetic Resonance Imaging
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• v.20 no.1
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• pp.36-43
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• 2016

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 ($B_1{^+}$ complex map) were acquired using a double-angle actual flip angle imaging MRI sequence. The conductivity and permittivity were estimated from the complex valued $B_1{^+}$ 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 $B_1{^+}$ 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.

• Journal of Oral Medicine and Pain
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• v.20 no.2
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• pp.477-487
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• 1995

The purpose of this study was to assess the thermographic differences of craniomandibular area between normal individual and patients with craniomandibular disorders and to compare the differences between clinical and thermographical assessment. The author had used 50 subjects as materials for this study, which was divided into 2 groups (first group included 15 healthy subjects and second group included 35 patients) with craiomandibular disorders; 17 subjects had normal disc-condyle relationship, 13 subjects had disc displacement with reduction and 5 subjects had disc displacement without reduction. Agema 870 thermovision(D.I.T.I.) was used to take thermographs with $0.1^{\circ}C$ difference of gradual temperature shift. The results were as follows : 1. Of 34 patients with craniofacial pain, 15(44%) subjects showed hyperthermia on the pain site in the thermography, 8(23.5%)exhibited hyperthermia on the site opposed to the pain site, and 11(32.4%) did not show any significant thermal change. One patient without craniofacial pain showed hyperthermia on the site opposed to the site of disc displacement without reductin. 2. Of 35 patients with craniofacial pain or disc displacement, 24(68.6%) subjects showed a significant thermal difference between symptomatic and asymptomatic sides of the face, but 11(31.4%) did not show any difference. 3. Of 17 patients with pain but with normal disc-condyle relationship, 8(47.1 subjects showed hyperthermia on the pain site, 4(23.5%) showed on the site opposed to the pain site, and 5(29.4%) did not show any significant thermal change. 4. Or 13 patients with pain and disc displacement with reduction, 6(46.2%) subjects showed hyperthermia on the pain site, 3(23.1%) showed on the site opposed to the pain site, and 4(30.8%) did not show any significant thermal change. 5. 15 healthy subjects did not show any thermal differences between the both sides of the face.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2359-2362
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• 2014

Background: To investigate the effects of double radiofrequency hyperthermia on Th1/Th2 cells in esophageal cancer patients treated with radiotherapy. Materials and Methods: 22 patients with esophageal cancer were divided into a radiotherapy group (10 cases) and a combined group (double radiofrequency hyperthermia combined with radiotherapy group, 12 cases). Both groups received conventional radiotherapy using a cobalt-60 therapy apparatus (TD60-66Gy/30-33F). Patients in the combined group also underwent double radiofrequency hyperthermia (2F/W, 8-10F). Before and after treatment, Th1, Th2, Tc1 and Tc2 cells in peripheral blood were determined with flow cytometry. Results: In the radiotherapy group, Th1 cell contents before and after radiotherapy were $17.5{\pm}5.26%$ and $9.69{\pm}4.86%$, respectively, with a significant difference (p<0.01). The Th1/Th2 ratio was significantly decreased from $28.2{\pm}14.3$ to $16.5{\pm}10.4 $(p<0.01). In the combined group, Th1 cell content before radiotherapy was $15.9{\pm}8.18%$, and it increased to $18.6{\pm}8.84$ after radiotherapy (p>0.05), the Th1/Th2 ratio decreasing from $38.4{\pm}36.3$ to $28.1{\pm}24.0$ (p>0.05). Changes in Th2, Tc1 and Tc2 cell levels were not significant in the two groups before and after therapy (p>0.05). Conclusions: Double radiofrequency hyperthermia can promote the conversion from Th2 to Th1 cells, and regulate the balance of Th1/Th2 cells.

• Journal of Korean Traditional Oncology
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• v.21 no.2
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• pp.63-74
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• 2016

Objective : The purpose of this study is to report the effects of radio-frequency hyperthermia cancer treatment in conjunction with Sorafenib on hepatocellular carcinoma patient. Method : The patient was diagnosed with hepatocellular carcinoma at S6/7 and treated with right posterior sectionectomy. After 4 months, tumor recurrence was found at S4, 5 and 8. After transarterial chemoembolization, the patient was prescribed Sorafenib (proprietary name $Nexavar^{(R)}$ ) as well as proceeding with radio-frequency hyperthermia. The clinical outcomes were measured by computed tomography, laboratory findings including tumor markers (AFP, PIVKA-II), natural killer (NK) cell activity, and numeric rating scales (NRS). Results : After the treatment, tumor size was decreased accompanying by reducing the level of tumor markers (AFP, PIVKA-II). Major clinical symptoms were improved with increasing NK cell activity. There were no adverse events based on National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Conclusion : This case suggests that radio-frequency hyperthermia has synergistic effect for the treatment of hepatocellular carcinoma patient in conjunction with Sorafenib.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.7
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• pp.732-739
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• 2002

Performance of the applicator for hyperthermia is determined by both the degree of impedance matching and specific absorption rate(SAR) distribution in the surrounding tissue. In this paper, the coaxial-slot antenna using staircasing approximation in the FDTD is analyzed and the coaxial-slot antenna for the hyperthermia improving heating characteristics is designed. The SAR of the coaxial-slot antenna approximated to staircasing and square model is analyzed, and the SAR of staircasing model is compared with Saito's SAR measurement and square model. As a result, the SAR of proposed model exhibited agreement with the Saito's measurement of square model. Ig averaged SAR on the liver caused by proposed antenna in this paper is 195 W/kg, and is about 27.9 % higher than the Saito's antenna 152.5 W/kg, respectively.