• The Journal of Korean Society for Radiation Therapy
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• v.11 no.1
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• pp.73-78
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• 1999

In general, the patients of the head and neck cancer are treated with 4MV photon beam up to prescribed dose, but spinal cord should be excluded in the treatment field. When its absorbed dose is limited at the tolerance dose. In case of the patients who has the positive posterior neck nodes need a boost electron beam treatment to the prescribed dose. In that case, the anatomical structure of the neck and the physical structure of the standard electron cone interrupt to allow proper access to the disease site. Therefore, we extended treatment SSD for the remove of the those hindrances. In this study, we evaluated the dosimetric variation of the standard electron cone for the extended SSD, from 100cm to 120cm, 5 cm increment, and compare to the custom-made electron cone. As a result, the $\%$ depth dose, the point of maximum dose and the range of maximum were changed within the $2\%$. The penumbra width was increased from 1.0cm to 2.0cm. However, the dosimetric characteristics of the custom-made electron cone was very similar to that of the 100cm SSD standard electron cone and due to its characteristic of physical structure, patients didn't need re-positioning after photon beam treatment, therefore accurate treatment was possible, we conclude that the custom-made electron cone was very useful for the clinical practice.

• Journal of Korean Neurosurgical Society
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• v.61 no.5
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• pp.625-632
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• 2018

Objective : Because the anatomical structure of the brachial plexus is very complex, surgical treatment of tumors in this region is challenging. Therefore, a lot of clinical and surgical experience is required for successful treatment; however, many neurosurgeons have difficulty accumulating this experience owing to the rarity of brachial plexus tumors. The purpose of this report is to share our surgical experience with brachial plexus tumor with other neurosurgeons. Methods : The records of 18 consecutive patients with brachial plexus tumors who underwent surgical treatment between January 2010 and December 2017 in a single institution were retrospectively reviewed. The surgical approach was determined according to the tumor location and size, and intraoperative neurophysiological monitoring (IONM) was used in most of cases to prevent iatrogenic nerve injury during surgery. In addition, to evaluate the differences in tumor characteristics according to pathologic diagnosis, the tumors were divided twice into two groups, based on two separate classifications, and statistical analysis was performed. Results : The 18 brachial plexus tumors comprised 15 (83.3%) benign peripheral nerve sheath tumors including schwannoma and neurofibroma, one (5.6%) malignant peripheral nerve sheath tumor, one (5.6%) benign tumor of non-neural sheath origin (neurogenic cyst), and one (5.6%) metastatic tumor (papillary carcinoma). The authors analyzed relationship between tumor size/location and tumor characteristic parameters such as age, size, right-left, and pathology. There were no statistically significant differences except a tendency of bigger tumor size in young age. Conclusion : For a successful surgical outcome, an appropriate surgical approach is essential, and the appropriate surgical approach is determined by the location and size of the tumor. Furthermore, applying IONM may prevent postoperative complications and it is favorable option for brachial plexus tumors surgery.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.328-334
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• 2013

The keratocystic odontogenic tumor (KCOT) is a unique cyst because of its locally aggressive behavior, high recurrence rate and characteristic histological appearance. Various options are available for treatment. While some clinicians advocate aggressive forms of dental treatment, others prefer more conservative therapy. In this study, two types of conservative surgical procedures were performed to treat the tumor; marsupialization and cyst enucleation. The patients showed healing process on conservative surgical treatment and teeth erupted without recurrence. Conservative surgical treatment can be an effective treatment option for young children because of their efforts to preserve teeth and other anatomical structures.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.440-448
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• 1996

Bronchial carcinoid tumors are uncommon, constituting approximately 3-5% of all primary lung cancers. Classification of these tumors has evolved substantially as our understanding of the cellular, biologic, and clinical aspects of these neoplasms has improved. Initially, bronchial carcinoids were thought to be benign and therefore were classified as bronchial adenomas. Currently, however, they are well recognized as having the potential for both local invasion and distant metastatic involvement. Consequently, carcinoid tumors are frankly malignant. Thus bronchial adenoma is a misnomer that should no longer be used for bronchial carcinoids. Most investigators currently favor classifying carcinoid tumors as a type of neuroendocrine neoplasm because of their potential to secrete a variety of chemical substances found in both the central nervous system and the epithelial cells of numerous organs. Bronchial carcinoids are usually characterized by a slow growth pattern and a low incidence of metastasis, and histologically conformed by the azurophil staining and the presence of the characteristic neurosecretary granule on electron microscopy. Atypical carcinoid tumor was first defined by Arrigoni et al, who proposed the following criteria for separation of atypical carcinoid from typical carcinoid tumor : 1) increased mitotic activity with 1 mitotic figure per 1-2 high power fields(or 5-10 mitoses /10 HPF), 2) nuclear pleomorphism, hyperchromatism, and an abnormal nuclear-cytoplasmic ratio, 3) areas of increased cellularity with disorganization of the architecture, and 4) tumor necrosis. In contrast, typical carcinoid tumor may have focal cytologic pleomorphism, but necrosis is absent and mitotic figures are rare. Recently we experienced a case of atypical bronchial carcinoid with multiple distant metastasis, so we report this case with a review of the literature.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.2
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• pp.58-62
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• 2002

The incidence of giant cell tumors represents only 5% to 10% of all bone tumors. Occurrence on the small bones of the hand and foot are very rare. They typically present with pain and sometimes a pathologic fracture or even soft tissue extension. The radiographic appearance is highly characteristic. An eccentric osteolytic lesion is seen, producing cortical thinning and expansion, and possessing a delicate trabecular pattern. In tarsal bones, poorly or well-defined osteolytic lesions of variable size are encountered. Surgical treatment remains the preferred therapy. Marginal or wide en bloc resection has had far better results in term of local recurrence. Several authors have suggested extended curettage and cement as an alternative to en bloc resection. Follow-up is necessary to monitor for both local recurrence and the infrequent pulmonary metastases.

• Archives of Craniofacial Surgery
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• v.12 no.2
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• pp.111-115
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• 2011

Purpose: Reconstruction of a full thickness defect of the nose is a difficult task for plastic surgeons because the anatomical characteristic, shape, and function of the nose all need to be taken into consideration. Most often, a local flap or a composite graft is used, but for a large defect, reconstruction using free flaps is the most ideal method. In free flap reconstruction, the chondrocutaneous preauricular area can be a suitable donor site. We performed a chondrocutaneous preauricular free flap with an interpositional vascular graft for reconstruction of a nasal ala. Methods: A 46 year-old male presented to the hospital with a right alar deformity induced by a dog bite. During the surgery, the existing scar tissue was removed and thereby a newly formed full thickness defect was reconstructed using the chondrocutaneous preauricular free flap with an interpositional vascular graft harvested from the descending branch of the lateral femoral circumflex vessel between the facial and superficial temporal vessels of the free flap. Results: The flap survived without flap loss and showed symmetry in its overall shape, contour, texture, and color. The patient was satisfied with the results and the surgery yielded no additional scars at the nasolabial fold area. Conclusion: The chondrocutaneous preauricular free flap is a valuable method in reconstruction of full thickness defects of the nose, and using the descending branch of the lateral femoral circumflex vessel as the interpositional vascular graft at the anastomotic site produces reliable results.

• Korean Journal of Head & Neck Oncology
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• v.39 no.1
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• pp.45-48
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• 2023

Angiosarcoma is a very rare subtype of sarcoma. It mainly occurs in the head and neck, and cutaneous angiosarcoma in this region seems to be a distinctive neoplasm with characteristic clinicopathologic features that differ from those of angiosarcoma in other anatomical locations. The prognosis of angiosarcoma in the head and neck region is poor, and the risk of local recurrence and metastasis is high. We reconstructed an atypical angiosarcoma that presented as a solitary nodule with a shape suggestive of hemangioma on the cheek using a modified bilobed local flap. At a 12-month follow-up visit, the patient in this case showed successful recovery after radiation therapy.

• Korean Journal of Radiology
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• v.22 no.10
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• pp.1690-1696
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• 2021

Objective: To describe the anatomic locations and imaging features of posterior lung herniation in unilateral pulmonary agenesis and aplasia, focusing on radiograph-CT/MRI correlation. Materials and Methods: A total of 10 patients (seven with pulmonary agenesis and three with pulmonary aplasia, male: female = 1:9, mean age 7.3 years, age range from 1 month to 20 years) were included. Chest radiographs (n = 9), CT (n = 9), and MRI (n = 1) were reviewed to assess the type of lung underdevelopment, presence of anterior and posterior lung herniation, bronchus origin, supplying artery, and draining vein of the herniated lung. Results: Pulmonary agenesis/aplasia more commonly affected the left lung (n = 7) than the right lung (n = 3). Anterior lung herniation was observed in nine of the 10 patients. Posterior lung herniation was observed in seven patients with left pulmonary agenesis/aplasia. Two patients showed posterior lung herniation crossing the midline but not beyond the aorta, and five patients showed the posteriorly herniated right lower lobe crossing the midline to extend into the left hemithorax farther beyond the descending thoracic aorta through the space between the esophagus and the aorta. This anatomical configuration resulted in a characteristic radiographic finding of a radiolucent area with a convex lateral border and a vertical medial border in the left lower lung zone, revealing a tongue-like projection on CT and MRI. Conclusion: Posterior lung herniation occurs in unilateral left lung agenesis/aplasia. Approximately 70% of the cases of posterior lung herniation reveal a unique radiolucent tongue-like projection in the left lower lung zone on imaging studies, which is caused by the extension of the posteriorly herniated right lung farther beyond the descending aorta.

• Korean Journal of Radiology
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• v.23 no.8
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• pp.821-827
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• 2022

Objective: To determine the anatomical characteristics of the petrous ridge and trigeminal nerve in trigeminal neuralgia (TN) without neurovascular compression (NVC). Materials and Methods: From May 2017 to March 2021, 66 patients (49 female and 17 male; mean age ± standard deviation [SD], 56.8 ± 13.3 years) with TN without NVC and 57 controls (46 female and 11 male; 52.0 ± 15.6 years) were enrolled. The angle of the petrous ridge (APR) and angle of the trigeminal nerve (ATN) were measured using magnetic resonance imaging with a high-resolution three-dimensional T2 sequence. Data on the symptomatic side were compared with those on the asymptomatic side in patients and with the mean measurements of the bilateral sides in controls. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of APR and ATN in distinguishing TN patients from controls. Results: In TN patients without NVC, the mean ± standard deviation (SD) of APR on the symptomatic side (98.40° ± 19.75°) was significantly smaller than that of the asymptomatic side (105.59° ± 22.45°, p = 0.019) and controls (108.44° ± 15.98°, p = 0.003). The mean ATN ± SD on the symptomatic side (144.41° ± 8.92°) was significantly smaller than that of the asymptomatic side (149.67° ± 8.09°, p = 0.003) and controls (150.45° ± 8.48°, p = 0.001). The area under the ROC curve for distinguishing TN patients from controls was 0.673 (95% confidence interval [CI]: 0.579-0.758) for APR and 0.700 (CI: 0.607-0.782) for ATN. The sensitivity and specificity using the diagnostic cutoff yielding the highest Youden index were 81.8% (54/66) and 49.1% (28/57), respectively, for APR (with a cutoff score of 94.30°) and 65.2% (43/66) and 66.7% (38/57), respectively, for ATN (cutoff score, 148.25°). Conclusion: In patients with TN without NVC, APR and ATN were smaller than those in controls, which may explain the potential cause of TN and provide additional information for diagnosis.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.1
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• pp.32-37
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• 2016

Purpose: To determine the anatomical characteristic of C-shaped canal systems in Korean mandibular 2nd molars by cone beam computed tomography (CBCT). Materials and Methods: The 824 CBCT images were evaluated. These patients were taken CBCT for the diagnosis and treatment of dental implantation on 2013. The 711 mandibular 2nd molars were examined. The configuration of root canal systems were classified according to modified Melton's classifications. Results: Of the 711 mandibular 2nd molars, 21.5% had C-shaped canal systems. This prevalence did not differ with tooth position. Most of the C-shaped canals with bilateral molars were symmetrical. Of the C-shaped canal, the most common configuration Type were Melton's Type I (89%) in the orifice level and Melton's III (83.8%) in the apical level. The prevalence of C-shaped canal was higher in female (25%) than male (13.9%) (P < 0.05). Conclusion: A high prevalence of C-shaped canals were observed in Korean mandibular 2nd molars. For successful C-shaped root canal treatment, the comprehension of root canal systems was important.