• Journal of the Korean Society of Radiology
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• v.14 no.6
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• pp.841-848
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• 2020

In the field of radiation therapy using photon beams and electron beams, since each patient has a different sensitivity to radiation, skin side effects may occur even at the same dose. Therefore, if there is a risk of excessive dose to the skin, a dosimeter is attached to verify whether the correct dose is being investigated. However, since the skin dosimeter checks the attachment site visually by measuring a point dose, it is difficult to confirm an accurate dose distribution. As a result, the measurement and simulation errors of the material HgI₂ in the 6 MV photon beam were 3.73% and 5.24%, respectively, at the minimum thickness of 25 ㎛, and the material PbI₂ was 4.73% and 5.65%, respectively. On the other hand, as a result of the 6 MeV electron beam, the measurement and simulation errors of the material HgI₂ were 1.35% and 1.12%, respectively, at a minimum thickness of 25 ㎛, and the material PbI₂ showed relatively low attenuation error, 1.67% and 1.20%, respectively. Therefore, it was evaluated that the thickness of the photon beam within 25 ㎛ and the electron beam within 100 ㎛ is suitable to have a reduction rate error within 5%. This study presents a new research direction for a flexible dosimeter attached to the human body that is required in clinical practice and the construction conditions of a future skin dosimeter.

• Journal of Chest Surgery
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• v.17 no.4
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• pp.753-761
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• 1984

Most patients having annuloaortic ectasia are associated with marked dilatation of the sinuses of Valsalva and the aortic annulus as well as the huge aneurysm of the ascending aorta. A 19 year old male patient complaining of tightness on left posterior chest wall underwent cardiac angiography in which demonstrated annuloaortic ectasia with ascending aortic aneurysm and aortic insufficiency. The patient had corrective operation replacing the ascending aorta and aortic valve with a composite graft[Dacron prosthesis containing a Bjork-Shiley aortic valve] within the aneurysmal sac. The coronary orifices were anastomosed to the tubular Dacron prosthesis [30 mm in diameter] by means of a second smaller Gore-Tex tube [8mm in diameter]. The aneurysmal sac was trimmed by removing the redundant wall and then wrapped outer wall of the Dacron prosthesis. Postoperatively, mediastinal bleeding was temporarily observed in the operative day and satisfactory blood pressure was maintained with small dose of dopamine. One week later, large amount of serous effusion was drained out of the retrosternal space making partial disruption of the skin which was healed well by daily local dressing. The patient discharged in good condition on postoperative 29th day with no residual complications and is doing very well on the 4 months follow-up.

• Korean Journal of Veterinary Research
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• v.61 no.1
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• pp.9.1-9.6
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• 2021

Factors such as location, volume, and the type of neoplasm complicate achieving tumor control. Electrochemotherapy (ECT) is a supplementary treatment for inoperable neoplasms in veterinary patients. Three dogs were diagnosed with a tumor. Two were squamous cell carcinoma (SCC), and the other was liposarcoma, each with a single tumor with the size range of 1 to 5 cm. The tumor locations were the cervical, oral, and abdominal cavity. ECT was selected as a treatment. Bleomycin was injected intratumorally at the dose of 0.5 to 1.0 mg/㎤. Five minutes after the injection, electric pulses applied in a sequence of eight pulses lasting 100 μsec each, were delivered in 1,000 V/cm. An evaluation was performed after 1 week, and the next session was administered 2 weeks later. In a patient with oral SCC, the tumor was in partial remission after two sessions of ECT. Another patient with SCC on her neck was showed complete remission after 2 weeks of ECT administration. A third patient showed stable disease for 8 weeks. Complications were mild and transient and included skin necrosis, edema, local pain, and gait disturbance. ECT is a valid adjuvant, especially for inoperable, cutaneous, or accessible intra-abdominal tumors.

• The Korean Journal of Pain
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• v.13 no.1
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• pp.38-43
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• 2000

Background: Preemptive analgesia may decrease postoperative pain by preventing nociceptive inputs generated during surgery. The preemptive effect of intravenous nalbuphine was examined in gynecological surgery. Methods: Forty female patients scheduled for gynecological surgery were randomly allocated into two groups. Each patient received 10 mg of intravenous nalbuphine as a bolus dose at the closure of peritoneum in group I (n=20) and before the skin incision in group II (n=20). After the bolus dose, the intravenous patient controlled analgesia (IV-PCA) which contained 50 mg of nalbuphine, 120 mg of ketorolac, 0.25 mg of droperidol and 90 ml of 5% dextrose water was given continuously at the rate of 2 ml/min. The postoperative visual analogue scale pain score (VAS), the total amount of the analgesics used, the degree of satisfaction of the patients and the developement of side effects were examined for 2 days. Results: VAS were significantly lower in group II than in group I after 9 and 12 hours. The cumulative consumption of analgesics in group II was significantly less than in group I. Most patients were satisfied with this regimen. There were no remarkable side effects. Conclusions: Preemptive analgesia with intravenous nalbuphine decreased postoperative pain and analgesic requirement. The analgesic effect of IV-PCA with nalbuphine-ketorolac was effective in control of postoperative pain in gynecologic surgery.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.235-241
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• 2008

If the target volume cannot be included with one field at head and neck cancer, we commonly used two or more field. It is very important to irradiate uniform dose at junction area of the fields. However, according to body shape of patient or general condition of patient, skin junction area can be matched incorrect, So overdose area or underdose area can be appeared in the junction area. This study researched therapy technique which can give uniform dose at skin junction owing to applying the edge block of lateral field at head and neck cancer. We measured the changed distance and rotational angle between central line of anterior supraclavicle lymph node and low margin of right lateral field on simulation process using the shielding block of variable rotation. As a result, the changed distance between central line of anterior supraclavicle lymph node and low margin of right lateral field was below 2mm to ${\pm}$10cm distance at central line of Y axis, changed angle was average 1.28 degree. But by using it the shielding block of variable rotation, the incorrect match at junction can be minimized. We think that this technique is very efficient one to apply this technique at head and neck cancered by the movement of organs can be not included, Therefore we have to pay attention on the process to imput MLC layer

• Imaging Science in Dentistry
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• v.31 no.3
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• pp.165-173
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• 2001

Objectives : To evaluate the absorbed and effective doses of spiral and computed tomography for the dental implant planning. Materials and Methods: For radiographic projection, TLD chips were placed in 22 sites of humanoid phantom to record the exposure to skin and the mean absorbed dose to bone marrow, thyroid, pituitary, parotid and submandibular glands and nesophagus. Effective dose was calculated, using the method suggested by Frederiksen et al.. Patient situations of a single tooth gap in upper and lower midline region, edentulous maxilla and mandible were simulated for spiral tomography. 35 axial slices (maxilla) and 40 axial slices (mandible) with low and standard dose setting were used for computed tomography. All the radiographic procedures were repeated three times. Results: The mean effective dose in case of maxilla was 0.865 mSv, 0.452 mSv, 0.136 mSv and 0.025 mSv, in spiral tomography of complete edentulous maxilla, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). That in case of mandible was 0.614 mSv, 0.448 mSv, 0.137 mSv and 0.036 mSv, in spiral tomography of complete edentulous mandible, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). Conclusions: Based on these results, it can be concluded that low mAs computed tomography is recommended instead of spiral tomography for the complete edentulous maxilla and mandible dental implant treatment planning.

• Journal of radiological science and technology
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• v.41 no.2
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• pp.141-148
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• 2018

This study examined the properties of photons and the dose distribution in a human body via a simulation where the total body irradiation(TBI) is performed on a pediatric anthropomorphic phantom and a child size water phantom. Based on this, we tried to find the optimal photon beam energy and material for beam spoiler. In this study, MCNPX (Ver. 2.5.0), a simulation program based on the Monte Carlo method, was used for the photon beam analysis and TBI simulation. Several different beam spoiler materials (plexiglass, copper, lead, aluminium) were used, and three different electron beam energies were used in the simulated accelerator to produce photon beams (6, 10, and 15 MeV). Moreover, both a water phantom for calculating the depth-dependent dosage and a pediatric anthropomorphic phantom for calculating the organ dosage were used. The homogeneity of photon beam was examined in different depths for the water phantom, which shows the 20%-40% difference for each material. Next, the org an doses on pediatric anthropomorphic phantom were examined, and the results showed that the average dose for each part of the body was skin 17.7 Gy, sexual gland 15.2 Gy, digestion 13.8 Gy, liver 11.8 Gy, kidney 9.2 Gy, lungs 6.2 Gy, and brain 4.6 Gy. Moreover, as for the organ doses according to materials, the highest dose was observed in lead while the lowest was observed in plexiglass. Plexiglass in current use is considered the most suitable material, and a 6 or 10 MV photon energy plan tailored to the patient condition is considered more suitable than a higher energy plan.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.666-668
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• 2006

Purpose: Livedo vasculitis is recurrent painful ulceration of the feet, ankles and legs characterized by purpuric papules and plaques that undergo superficial necrosis and healing with residual white atrophic scars (atrophie blanche). The typical histopathologic findings of livedo vasculitis are characterized by endothelial proliferation and hyaline degeneration along with thrombosis of dermal vessels. Standard therapeutic strategies for treatment of livedo vasculitis are usually on the basis of rheologic, anti-inflammatory or immnosuppressive treatments, a aspirin, dipyridamole, glucocorticosteroids, pentoxyfylline, or high-dose intravenous immunoglobulin are often ineffective or partially effective. Methods: We report a case of 24-year-old male patient with livedo vasculitis on the ankles and dorsal surfaces of both feet. Results: The lesion that had been unresponsive to medical treatment were successfully healed with complete debridement and skin grafting without recurrences. Conclusion: Surgical treatment can be one of the therapeutic choice in Livedo vasculitis.

• Annals of Clinical Neurophysiology
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• v.5 no.2
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• pp.210-213
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• 2003

POEMS syndrome is a multisystem disorder associated with polyneuropathy, organomegaly, endocrinopathy, a monoclonal protein(M-protein), and skin change. Recently we have had the opportunity to attend one patient with clinical features similar to this syndrome. He was a 46-year-old man who had a progressive polyneuropathy, swallowing difficulty, hepatosplenomegaly, hypothyroidism, IgA ${\lambda}type$ monoclonal gammapathy, specific skin change and ascites. His symptoms such as low extrimity pain and weakness, swallowing difficulty were improved by high-dose 7S-IgG. Thus, we report a case with a review of the literature.

• Progress in Medical Physics
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• v.27 no.2
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• pp.93-97
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• 2016

In this study, we evaluate the effect of respiration on the dose distribution in patient target volume (PTV) during intensity-modulated radiation therapy (IMRT) and research methods to reduce this impact. The dose distributions, homogeneity index (HI), coverage index (CVI), and conformity index of the PTV, which is calculated from the dose-volume histogram (DVH), are compared between the maximum intensity projection (MIP) image-based plan and other images at respiration phases of 30%, 60% and 90%. In addition, the reducing effect of complication caused by patient respiration is estimated in the case of a bolus and the expended PTV on the skin. The HI is increased by approximately twice, and the CVI is relatively decreased without the bolus at other respiration phases. With the bolus and expended PTV, the change in the dose distribution of the PTV is relatively small with patient respiration. Therefore, the usage of the bolus and expended PTV can be considered as one of the methods to improve the accuracy of IMRT in the treatment of breast cancer patients with respiratory motion.