• Korean Journal of Bronchoesophagology
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• v.2 no.1
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• pp.71-81
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• 1996

The normal larynx locates to the front of the neck symmetrically and the thyroid notch lies in the center of the neck, but practically the larynx is not symmetric in all people. From a clinical point of views, there are vague cases to decide whether a disordered laryngeal structure is within normal variations or a pathologic condition. The purpose of this study is to investigate the anatomy of the laryngeal framework in normal population. Authors investigate various measures of normal laryngeal framework, such as symmetry and length of the larynx, levels of the hyoid bone and vocal cord and angle of thyroid cartilage by using calipers and protractor on 45 cases of neck CT. The results are summerized as follows. 1. The laryngeal framework was asymmetric to a greater or lesser extent in most cases with directional preponderance to the right side. The degree of asymmetry did not differ among different age groups and between seres. 2. The level of the hyoid bone ranged from C2-C3 vertebrae to C5-C6 intervertebral space with most frequent level of C5. 3. The level of the vocal cord ranged from 01 vertebra to C6-C7 intervertebral space with most frequent level of C5. 4. The angle of thyroid cartilage ranged from 58 degree to 100 degree with average of 81.5 and mean angle between both thyroid alae were 77.24 degree in male and 87.88 degree in female.

• Journal of Chest Surgery
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• v.29 no.9
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• pp.1003-1009
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• 1996

Although esophagogastric (EG) anastomosis with a circular surgical stapler (EEA or ILS) is a safe find convenient proc dure with less anastomotic leakage, a concern for the anastomotic stricture still remains, especially in patients with small esophagus. We modified cervical EG anastomotic technique using straight thoracoscopic endostapler to prevent EG anastomotic stricture. Prospective clinical study was performed to determine the feasibility of our modification using Endo-GIA (US Surgical Corp., Worwalk), during the period from October, 1994 to July, 1995, in thirteen patients with carcinoma of the thoracic esophagus. A stomach tube was reanastomosed to the cervical esophagus utilizing a 30 mm Endo-GIA after esophagectomy and node dissection. There was one early mortality due to respiratory failure and pulmonary tuberculosis. Anastomotic leakage with resultant stricture was noticed in one patient, and it was re- lated to ischemic necrosis of the stomach tube. The overall incidence of stricture was 7.6 % (1113). During the 8 month follow-up period, the remaining 11 patients did not show any clinica evidence of stricture such as dysphagia. All patients were on a regular diet. We conclude that our new technique for cervical EG anastomosis with GIA-Endo stapler is a safe and convenient procedure in preventing anastomotic stricture.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.165-174
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• 1990

The purpose of the study was to correlate margin design(chamfer, shoulder, shoulder with a $45^{\circ}$ bevel. with the seating and sealing of cemented full cast crowns under standardized simulated clinical conditions. Wax patterns were made with milled stainless-steel dies and rings, and were invested, burnt out, and cast. The full cast crowns were comented on individual resin dies, and a gradually diminishing load(45kg to 25kg. was applied over a 10-minute period. The specimens were sectioned centrally with a low speed diamond saw and examined with light microscope. The results were as follows : 1. Chamfer preparations demonstrated it was the best marginal seal, followed in order by the shoulder with a $45^{\circ}$ bevel, and by the shoulder(p<.05). 2. Chamfer preparations demonstrated it was the best occlusal seating, followed in order by the shoulder, and by the shoulder with a $45^{\circ}$ bevel(p<.05).

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.80-83
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• 2011

Purpose: Traumatic posterior dislocation of the shoulder in a child is extremely rare, and posterior dislocation of the shoulder concomitant with ipsilateral humeral surgical neck fracture has not been reported in a child previously in Korea. Materials and Methods: The authors treated a 10-year-old with posterior dislocation of left shoulder and an ipsilateral humeral surgical neck fracture, that occurred during Taekwondo practice, by open reduction of the shoulder and pin fixation under general anesthesia. Results: A normal range of motion with complete union and good remodeling was achieved without redislocation or avascular necrosis of humeral head at 1 year after surgery. Conclusion: The authors report a successfully treated case of traumatic posterior dislocation of the shoulder with an ipsilateral humeral surgical neck fracture in child.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.6
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• pp.1153-1158
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• 2006

The classification of the background and cell areas is very important research area because of the ambiguous boundary. In this paper, the region of cell is extracted from an image of uterine cervical cytodiagnosis using the region growing method that increases the region of interest based on similarity between pixels. Segmented image from background and cell areas is binarized using a threshold value. And then 8-directional tracking algorithm for contour lines is applied to extract the cell area. First, the extracted nucleus is transformed to RGB color that is the original image. Second, the K-means clustering algorithm is employed to classify RGB pixels to the R, G, and B channels, respectively. Third, the Hue information of nucleus is extracted from the HSI models that is the transformation of the clustering values in R, G, and B channels. The backpropagation algorithm is employed to classify and identify the normal or abnormal nucleus.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.1
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• pp.52-59
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• 2022

Decalcification of the buccal surface of the teeth often occurs during fixed orthodontic treatment. This case report describes two cases in which cervical decalcificated teeth that occurred during orthodontic treatment were treated with direct resin veneer restoration. Early lesions without caries can be remineralized through periodic fluoride application, diet control, and oral hygiene improvement. As it progresses, appropriate repair treatment is required, and it is more preferable to focus on prevention rather than treatment after the occurrence of the lesion.

• Journal of the Korea Society of Computer and Information
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• v.29 no.6
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• pp.143-151
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• 2024

In this paper, the inductor current distortion in a boost PFC (Power Factor Correction) converter under light load is mathematically analyzed, and its reasons are defined. In the average current mode control under light load, the inductor current is discontinuous, resulting in an inaccurate inductor current average value being reflected in the current control. In predictive current mode control, the current ripple is relatively large compared to the inductor current, leading to severe current distortion. In addition, the switch is turned off near the peak of the inductor current when model predictive current control is applied. Inductor current distortion must be addressed because it leads to an increase in total harmonic distortion and a decrease in power factor. In this paper, the design procedure to mitigate the light load current distortion in boost PFC converter is selected based on the mathematical analysis. Finally, a comparative analysis of control methods under light load is performed using hardware-in-the-loop simulation.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.3
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• pp.224-231
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• 2010

Purpose: This study was to investigate how the crestal module design could affect the level of marginal bone stress around dental implant. Materials and methods: A submerged implant of 4.1 mm in diameter and 10 mm in length was selected as baseline model (Dentis Co., Daegu,Korea).A total of 5 experimental implants of different crestal modules were designed (Type I model : with microthread at the cervical 3 mm, Type II model : the same thread pattern as Type I but with a trans-gingival module, Type III model: the same thread pattern as the control model but with a trans-gingival module, Type IV model: one piece system with concave transgingival part, Type V model: equipped with beveled platform). Stress analysis was conducted with the use of axisy mmetric finite element modeling scheme. A force of 100 N was applied at 30 degrees from the implant axis. Results: Stress analysis has shown no stress concentration around the marginal bone for the control model. As compared to the control model, the stress levels of 0.2 mm areas away from the recorded implant were slightly lower in Type I and Type IV models, but higher in Type II, Type III and Type V models. As compared to 15.09 MPa around for the control model, the stress levels were 14.78 MPa, 18.39 MPa, 21.11 MPa, 14.63 MPa, 17.88 MPa in the cases of Type I, II, III, IV and V models. Conclusion: From these results, the conclusion was drawn that the microthread and the concavity with either crestal or trans-gingival modules maybe used in standard size dental implants to reduce marginal bone stress.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.169-180
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• 1999

Background: Uterine cervical cancer is the most common malignant tumor of the women in Korea. This study was undertaken to evaluate the usefulness of the cervicography as a screening test of cervical cancer. Materials and Methods: Cervicography was taken from 482 women at department of obstetrics and gynecology, at Yeungnam University Hospital from March 1, 1998 to October 31, 1999. Of the 482 women, 172 women were exc1uded from the study for various reasons, and 310 women completed the study. Three-hundred and ten women had cervical cytology (Papanicolaou smear), cervicography and colposcopy, and punch biopsy was undertaken if any of the test result was abnormal. Results: The most common age group was 35-39, and 40-44, 45-49 in order and most common reason for having a screening test was regular check for cervical cancer. The mean duration from the last Pap smear was 17.1 months, and 64 women(20.4%) never had any prior screening tests. Of the 310 women, 254 women were categorized as normal or having benign disease such as cervicitis, erosion or metaplasia. Biopsy was taken from 56 patients and the results were 26 chronic cervicitis, 4 mild dysplasia, 6 moderate dysplasia, 2 severe dysplasia, 14 carcinoma in situ and 4 invasive carcinoma. The results of cytology and cervicography were well correlated(p<0.05). The sensitivity and specificity of cytology were 86.7% and 76.9%, respectively and the sensitivity and specificity of cervicography were 56.7% and 96.2%, respectively. False negative rate of cervicography(43.3%) was much higher than those of cytology(13. 3%) (p<0.05), but false positive rate of cervicography(3.8%) was much lower than that of cytology(23.1%) (p<0.05). Conclusion: It seems inappropriate to use cervicography as a single screening test for cervival cancer, but it may be an effective complementary test for cytology to lower the false negative rate of cytology.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.219-226
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• 2007

Purpose: The aim of this retrospective analysis was to analyze the results of radiotherapy administered to patients with neck node metastases from an unknown primary cancer, with or without neck dissection. Materials and Methods: From January 1986 to December 2005, 88 patients with neck node metastases from an unknown primary cancer were treated with curative intent. The age of the patients ranged from 35 to 74 years (median age, 59 years). There were 74 male and 14 female patients. Distribution of patients by N status was as follows: N1, 4 patients; N2a, 10 patients; N2b, 48 patients; N2c, 8 patients; N3, 18 patients. Fifty-one patients underwent neck dissection and 37 patients had only a biopsy (31 patients had fine-needle aspiration and 6 patients had an excisional biopsy). All patients received radiotherapy. The follow-up time ranged from 1 to 154 months, with a median time of 32 months. Results: The overall survival (OS) and disease-free survival (DFS) rate at 5 years were 43.9% and 41.7%, respectively. The factors associated with the OS rate were neck dissection, and a subsequent primary tumor. Factors associated with the DFS rate were N stage, neck dissection, and a subsequent primary tumor. Neck failure was noted in 15 patients, distant metastases in 18 patients, and a subsequent primary tumor in 8 patients. Conclusion: With comprehensive radiotherapy given to the bilateral neck and the potential mucosal sites, good survival rates can be obtained in patients with neck node metastases from an unknown primary cancer. However, considering the side effects, a randomized trial is required to determine the optimal radiotherapy volume.