• Journal of Magnetics
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• v.22 no.1
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• pp.141-145
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• 2017

This paper uses a glass dosimeter to evaluate the lens-absorbed dose of scattered radiation generated in tomotherapy intensity modulated radiation therapy (IMRT). The head and neck portion of the rando phantom was subjected to a CT scan. The tomotherapy plan was designed to ensure delivery of the prescribed total 70 Gy day 2.2 Gy. With the lens portion of the glass dosimeter, a 5mm bolus was subjected to the scattered radiation treatment, and the dose was measured in each of the three megavoltage CT (MVCT) modes. The result is multiplied by 30 times and was determined once as the mean value. The measurement at the MVCT Coarse mode is RT mode 10.797 mGy, that for the Normal mode is 13.360 mGy, for the Fine mode is a maximum of 22.872 mGy, and for the treatment mode is 895.830 mGy. A small amount of scattered radiation in the MVCT is measured in the lens scattered radiation, but scattered radiation during treatment was measured to be near 1 Gy on the lens. Compared to a one-time radiation treatment of 2.2 Gy, the survey showed something unexpected in that it was half the value of that research to the patient. Therefore, will be aware of how much of an influence there will be on sensitive organs, such as the lens by scattered radiation generated during intensity modulated radiation therapy.

• Proceedings of the Korean Magnestics Society Conference
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• 2015.11a
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• pp.55-55
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• 2015

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.251.1-251.1
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• 2008

• Journal of Magnetics
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• v.21 no.3
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• pp.425-430
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• 2016

The aim of this study was to measure the setup variation for X (lateral), Y (longitude), and Z (vertical) by taking magnetic megavoltage computed tomography (MVCT) before treating the brain, oropharynx, lung, and prostate patients on helical tomotherapy. In this study, 30 patients were chosen for each of the treatment areas, and their skin was labeled with a mark on a treatment planning reference point when taking CT. We preceded MVCT prior to tomotherapy and then conducted an auto registration based on the bony landmarks; image registration was used for automatically matching the patient's setup. Lastly, we confirmed and evaluated the translation coordinates of the images for 30 patients. The following shows the comparison result of the setup errors of each part: X (lateral) showed the highest setup errors with $3.44{\pm}2.05$ from Lung; Y (longitude) showed the highest setup errors showing $3.40{\pm}2.87mm$ from Prostate; and Z (vertical) showed the highest setup errors showing $6.62{\pm}4.38mm$ from Lung. This result verifies that the setup error can be prevented by taking MVCT before the treatment, and Planning Target Volume (PTV) margins can be reduced by referring to the resulting value of each treatment part. Ultimately, the dosage of the normal organs can be decreased as well as any side effects.

• Journal of the Korean Magnetics Society
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• v.20 no.4
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• pp.167-172
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• 2010

To meet on going challenges in nano-biomedical technology, the convergence of "spintronics", "biomedical" technology is a major break through in imaging, diagnosis and therapy, high-throughput genomic analysis. Especially magnetic bioassay is one of crucial devices for early diagnosis of specific analytes, point-of-care and U-health care application. In this paper, current status on high resolution magnetic sensors for bioassay and on-chip magnets for biomolecule transportation will be reviewed.

• Journal of the Korean Magnetics Society
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• v.21 no.1
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• pp.32-36
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• 2011

We fabricated a sensor for measuring the water level and water temperature using GMR-SV (giant magnetoresistance-spin valve) device, simultaneously. It could be applied to the medical cooling system of the potassium titanylphosphate KTP) laser system for the therapy of a benign prostatic hyperplasia. The middle point of GMR-SV device was set to the near position of a high magnetic sensitivity with 2.8%/Oe. The sensitivity for the water level and water temperature of the fabricated sensor were $400\;m{\Omega}/mm$ and $100\;m{\Omega}/^{\circ}C$, respectively.

• Journal of Magnetics
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• v.19 no.4
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• pp.357-364
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• 2014

This study examined effect of a transcranial magnetic stimulation device with a commercial-frequency approach on the neuronal cell death caused ischemia. For a simple transcranial magnetic stimulation device, the experiment was conducted on an ischemia induced rat by transcranial magnetic stimulation of a commercial-frequency approach, controlling the firing angle using a Triac power device. The transcranial magnetic stimulation device was controlled at a voltage of 220 V 60 Hz and the trigger of the Triac gate was varied from $45^{\circ}$ up to $135^{\circ}$. Cerebral ischemia was caused by ligating the common carotid artery of male SD rats and reperfusion was performed again to blood after 5 minutes. Protein Expression was examined by Western blotting and the immune response cells reacting to the antibodies of Poly ADP ribose polymerase in the cerebral nerve cells. As a result, for the immune response cells of Poly ADP ribose polymerase related to necrosis, the transcranial magnetic stimulation device suppressed necrosis and had a protective effect on nerve cells. The effect was greatest within 12 hours after ischemia. Therefore, it is believed that in the case of brain damage caused by ischemia, the function of brain cells can be restored and the impairment can be improved by the application of transcranial magnetic stimulation.

• Journal of Magnetics
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• v.19 no.3
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• pp.255-260
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• 2014

A portable clip-type pulsimeter equipped with a magnetic sensing Hall device has been developed to raise the accuracy of oriental disease diagnosis and therapy by convergence of magnetism and oriental medicine. To improve accuracy and reliability of conventional pulsimeter due to subjective analysis of the pulse wave and measuring position dependency of the arterial pulse sensor, the fuzzy algorithm was applied to analyze the strong- and weak-pulse wave symptom. Optimal time for electronic acupuncture was calculated using fuzzy rules and interference were drawn from objective data in view of pre-treatment. Moreover, the electrical characteristics of the pain parts that respond to acupuncture point were applied in view of post-treatment to propose the scientific pulse wave algorithm and simulation experiment.

• Journal of Magnetics
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• v.19 no.2
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• pp.170-173
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• 2014

The purpose of the present study was to investigate the effect of repetitive transcranial magnetic stimulation (rTMS) in conjunction with task oriented training, on cortical excitability and upper extremity function recovery in stroke patients. This study was conducted with 31 subjects who were diagnosed as a hemiparesis by stroke. Participants in the experimental (16 members) and control groups (15 members) received rTMS and sham rTMS, respectively, during a 10 minutes session, five days per week for four weeks, followed by task oriented training during a 30 minutes session, five days per week for four weeks. Motor cortex excitability was performed by motor evoked potential and upper limb function was evaluated by motor function test. Both groups showed a significant increment in motor function test and amplitude, latency in motor evoked potential compared to pre-intervention (p < 0.05). A significant difference in post-training gains for the motor function test, amplitude in motor evoked potential was observed between the experimental group and the control group (p < 0.05). The findings of the current study demonstrated that incorporating rTMS in task oriented training may be beneficial in improving the effects of stroke on upper extremity function recovery.

• Journal of Magnetics
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• v.16 no.3
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• pp.253-258
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• 2011

The purpose of this study was to identify the effect of pulsed electromagnetic fields on the expression of neurotrophic factors after spinal cord injury. Sprague-Dawley male rats were given a spinal cord hemisection and randomly divided into 2 groups, the control and experimental groups. The experimental group was administered a fifteen minutes session of pulsed electromagnetic field once a day, five days a week. In order to observe the effect of these pulsed electromagnetic fields, this study observed the BDNF expression in the rat's lumbar spinal cord and the H&E staining in the gastrocnemius at 3, 7, 14, 21 days group after spinal cord hemisection. The results of this showed that the immunoreactivity of the BDNF in the rat's spinal cord gradually increased in each group. At 21 days, there is a significant difference between the control and experimental groups. The morphological shape of the gastrocnemius was gradually changed from 3days to 21days, and the gastrocnemius at 21 days was significantly degraded. However, the experimental group showed a slightly more organized gastrocnemius than the control group at 21days. The Results of this study suggest that pulsed electromagnetic field application decreases the degeneration of a rat's gastrocnemius morphology, and increases the immunoreactivity of the BDNF in the rat's spinal cord after spinal cord hemisection.