• Journal of the Korean Society of Radiology
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• v.15 no.3
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• pp.273-279
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• 2021

Metal material inserted into the body have a large difference in density from human tissues or bones around the Metal during CT scans.. Therefore, the Metal material inserted into the body produces Artifact. Metal Artifact, which occurs around Metals, can degrade the quality of CT images, causing confusion when medical team diagnose lesions. Through this experiment, we confirm that the occurrence of Artifacts decrease by using Dual energy CT and MAR algorithm in Single source Dual energy CT. We also want to present basic data on clinical application methods by comparing and analyzing the characteristics of images obtained by each method. Using GE 750HD CT, artificial implants were scanned using general method and Dual energy. Then we apply the MAR algorithm to each image obtained. And all previously acquired images were compared and analyzed the characteristics of the examination, such as image quality evaluation and dose evaluation. Images with MAR algorithm and Dual Energy confirmed a decrease in Metal Artifact. Images with MAR algorithm have reduced Metal Artifact, but have the disadvantage of distorting the details of artificial joint implants. On the other hand images teseted with Dual Energy have the advantage of being able to implement details than those applied with MAR algorithms, it takes longer to reconstruct the image and the exposure dose was about four times higher than those applied with MAR algorithm. In order to locate Metals, such as the post-operative follow-up period, it is useful to apply MAR algorithm to obtain images. And it is more useful to examine with Dual Energy when micro lesion identification, such as cardiac examination, and surgical planning or when tests are performed in diagnostic way.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.869-875
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• 1997

Perimembranous ventri ular septal defects(PMVSDS) are the most common type of ventricular septal defects(VSDs) and consist morphologically of deficiency of the membranous septum and variable portions of the adjacent muscular septum. Repair of VSD has begun via a right ventriculotomy. Even with this exposure, however, it mght lead to ventricular dysfunction. Transatrial exposure of VSDs is luiown to a versatile approach to PMVSDS and even malaligunent defects can be repaired by this method. Although transatrial exposure can be improved by taking down'the atrioventricular valve at the annulus, surgeons have been hesitant to do so because of concern for valvular competence. Therefore, this study was undertaken to clarity the effects of transamlular approach of tricuspid valve (TATV) at operation of PMVSD. During last 5 years, twenty eight cases from 96 patients of PMVSD were closed by TATV and follow up study was done from 3 months to 33 months and results were obtained as follows. 1. Age at operation was fr m 4 months to 38 years and most patients(17, 62%) were above 5 years. 2. Preoperative pulmonary-systemic flow ratio(QPIQS) was ranged from 1 to 2.8 and 22 patients(79%) were less than 2. 3. Peak systolic pulmonary artery pressure was below 30mmHg in 8, 30-50mmHg in 17, above 50mmHg in 3 patients and 25 patients(89%) were less than 50mmHg. 4. Preoperative tricuspid regurgitation(TR) is none in 12, trivial in 6, mild in 3, moderate in 5, severe in 2 patients but postoperative TR was none in 18, trivial in 6, mild in 4 patients, so TR in most patients had decreased or not. 5. Indications for operation were based on the presence of a significant shunt. However, in patients with small shunts, indications for operation were included additional factors, tricuspid valve pouch, RVOT obstruction(right ventricular outflow tract obstruction), subacute bacterial endocarditis and associated anomalies. 6. There were no hospital deaths and residual shunts in postoperative echocardiography. Therefore TATV is especially a good method in PMVSn where patients have trcuspid valve pouch. And it is a safe and effective technique that improves exposure for PMVSD repair and does not adversely affect tricuspid valvular competence.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.322-328
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• 1993

The trauma has been known as a major etiologic factor in temporomadibular joint disorders. The endotracheal intubation is suspected as one of the traumatic factor to temporomandibular disorder. But there are few reports about the amount of mouth opening during endotracheal intubation and temporomandibular joint disorder after endotracheal intubation. The authors studied the effects of endotracheal intubation to temporomandibular joint with 70 patients given surgical operation through general anesthesia. The results were as follows. 1. The mean amount of mouth opening for entire patients during endotracheal intubation was 26.3mm (s, d : 2.6), for oral intubation group 25.9mm(s, d : 3.2), for nasal intubation group 26.6mm(s, d : 1.9). There was no difference between two group stastically. (p<0.05) 2. 1 week later endotracheal intubation, the maximum mouth opening increased 1.5mm for entire patients, 1.5mm for oral intubation group, 1.6mm for nasal intubation group than behare endotracheal intubation. 3. Five patients complained the discomforts around temporomandibular joint after endotracheal intubation. The amount of mouth opening during endotracheal intubation was within physiologic range. It seemed that $45^{\circ}$ upward endoscopic lifting for exposure of glottis gave trauma to temporomandibular joint.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.220-227
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• 2017

Pre-eruptive intracoronal resorption (PEIR) is a rare radiolucent lesion often located within the dentin and adjacent to the dentin-enamel junction, underneath the occlusal aspect of the crowns of unerupted teeth. The treatment approaches for these lesions involved with unerupted teeth have been known as to be relatively simple; depending on the extent of resorption, follow-up or restoration can be performed after surgical exposure. However, once the tooth is exposed to the oral cavity after eruption, it becomes highly vulnerable to the development of carious lesions. Thus, immediate intervention is required in such cases; failure to address it may result in the need for more complex treatments including endodontic therapy. The aim of this case report was to describe the characteristics of PEIR and the clinical management of the impacted immature permanent teeth diagnosed with PEIR.

• Journal of Periodontal and Implant Science
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• v.25 no.1
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• pp.1-13
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• 1995

Chlorhexidine and Listerine are widely used in dentistry due to its effectiveness on plaque control and bactericidal action. The effects of these agent on chronic gingivitis and wound healing following surgical periodontal therapy in human has been favorable. Understanding the effects of chlorhexidine and Listerine on human gingival fibroblast will provide the rationale for its use during the healing process of periodontal surgery. The purpose of this study was to compare the effects of chlorhexidine and Listerine on human gingival fibroblast. Human gingival fibroblasts were cultured from the healthy gingiva on the extracted premolar of orthodontic patients. Human gingival fibroblast were trypsinized and cultured in growth medium added range of 0.0012-0.12% chlorhexidine and 1-100% Listerine mouth wash solution. The cell used in this study were between fifth to eighth passage number. The cell morphology were examined by inverted microscope and the cell activity were measured by MIT assay. The Morphology of gingival fibroblast added Chlorhexidine and Listerine at the concentration of all range were became globular and lost their cytoplasmic process. Our results indicate that a 0.0012 concentration of chlorhexidine and 1% concentration of Listerine were shows minimal cytotoxicity, but above these concentraion, there was a significant difference between the cell activity in the experimental group and control group(p

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.32-36
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• 2007

Background and Objective：A post-operative hypertrophic scar of the anterior neck is the leading complaint of the patients who underwent conventional thyroid surgery. In order to minimize the post-operative scar of the anterior neck, we performed thyroidectomy via axillary approach using operating microscope and a specialized retractor to determine technical feasibility. Patients and Methods：From January 2005 to December 2006, we performed thyroidectomy via axillary approach under operating microscope(f=400mm, ${\times}2.5$；OPMI $pico^{(R)}$；Zeiss, Germany) for benign unilateral nodule in 25 cases(all female, average age 34.5yrs). Under general anesthesia less than 7cm of skin incision was made in the axilla of ipsilateral side. A subcutaneous tunnel went over the pectoralis major muscle and the clavicle, and then through the sternocleidomastoid muscle and sternothyroid muscle was excised. The area around the thyroid was sufficiently dissected, and then a retractor designed for exposure via axillary approach was placed within the tunnel and under operating microscope thyroidectomy was performed. Results：There were 17 cases of thyroid nodulectomy and 8 cases of subtotal lobectomy. The mean average operative time was 102.64minutes. Postoperative complications included one case of postoperative bleeding, one case of temporary vocal cord paralysis, two cases of delayed wound healing, two cases of paresthesia of shoulder and arm, and two cases of hypertrophic scar of the axilla. Postoperative histopathology includes 17 cases of adenomatous hyperplasia, six cases of cyst, and two cases of follicular adenoma. For all cases hospitalization period was two days. Conclusion：Thyroidectomy via axillary approach under operating microscope has a good cosmetic advantage without a post-operative scar of the anterior neck. The procedure is simple due to direct vision using operating microscope, easy to identify important structures by magnifying them, and therefore surgical time can be reduced.

• Archives of Plastic Surgery
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• v.43 no.2
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• pp.204-209
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• 2016

Temporal hollowing occurs to varying degrees after pterional craniotomy. The most common cause of temporal hollowing is a bony defect of the pterional and temporal regions due to the resection of the sphenoid ridge and temporal squama for adequate exposure without overhang. The augmentation of such bony defects is important in preventing craniofacial deformities and postoperative hollowness. Temporal cranioplasty has been performed using a range of materials, such as acrylics, porous polyethylene, bone cement, titanium, muscle flaps, and prosthetic dermis. These methods are limited by the risk of damage to adjacent tissue and infection, a prolonged preparation phase, the possibility of reabsorption, and cost inefficiency. We have developed a method of temporal augmentation using a calvarial onlay graft as a single-stage neurosurgical reconstructive operation in patients requiring craniotomy. In this report, we describe the surgical details and review our institutional outcomes. The patients were divided into pterional craniotomy and onlay graft groups. Clinical temporal hollowing was assessed using a visual analog scale (VAS). Temporal soft tissue thickness was measured on preoperative and postoperative computed tomography (CT) studies. Both the VAS and CT-based assessments were compared between the groups. Our review indicated that the use of an onlay graft was associated with a lower VAS score and left-right discrepancy in the temporal contour than were observed in patients undergoing pterional craniotomy without an onlay graft.

• Journal of Korean Neurosurgical Society
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• v.39 no.5
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• pp.329-334
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• 2006

Objective : In selected cases, the transsphenoidal approach[TSA] can be extended anteriorly to the tuberculum sellae, chiasmatic sulcus, and planum sphenoidale to obtain direct exposure of the suprasellar cisterns and its contents. We applied this modification of the TSA to various lesions of the presellar and suprasellar areas. We evaluate our clinical experience of this technique and review the related literature. Methods : From 1999 to 2004, we used the transsphenoidal supradiaphragmatic intradural approachs[TSIAs] in 9 patients who had various lesions at the pre- and suprasellar regions. Concomitant presellar extension of the bone window was performed with the sublabial or transnasal transseptal transphenoidal techniques. After removal of the lesions, sellar or anterior cranial floor was repaired with silicone plate substitute. Results : The TSIAs have been applied in the following cases : four tuberculum sellae meningiomas, two craniopharyngiomas, two Rathke's cleft cysts, and one non-functioning macroadenoma. The complications were one case of visual acuity decrease and one cerebrospinal fluid rhinorrhea. Conclusion : The TSIA is easily applicable through a minor modification of the standard TSA. It is suitable for removing lesions located in the presellar and suprasellar area adjacent to the pituitary stalk with minimal brain manipulation and decreased morbidity.

• Journal of Korean Neurosurgical Society
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• v.37 no.6
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• pp.410-415
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• 2005

Objective: The aim of our study is to evaluate the effectiveness of unilateral hemilaminectomy for bilateral decompression in elderly patients with degenerative spinal stenosis. For this purpose, we studied the co-morbid condition and clinical outcome of patients who underwent decompressive surgery using the unilateral approach technique. Methods: Thirty-four patients over 65years of age who underwent unilateral partial laminectomy for bilateral decompression from January 2000 to October 2003 were analyzed. These patients were studied for preoperative co-morbid condition and physical status according to the American Society of Anesthesiologists(ASA) classification, postoperative morphometrical change, and clinical outcomes, including visual analogue scale(VAS) score. The mean follow-up was 23months (range 6 - 48months). Results: A patient's physical status was recorded as class I, II, or III by ASA classification, which correlated to 41.2%, 44.1%, and 14.7% of patients, respectively. The cross-sectional area of the pre- and postoperative dural sac at the level of the stenosis was $52.5{\pm}19.9mm^2$ and $110.6{\pm}18.2mm^2$, respectively. The outcome was excellent in 8.8%, good in 58.8%, fair in 23.6%, and poor in 8.8% of the patients. The VAS was changed postoperatively to $3.1{\pm}1.2$. There was no operation-related transfusion yet there was no evidence of postoperative instability at the follow-up examination. Conclusion: Unilateral laminectomy for bilateral decompression, in spite of the limited exposure, can result in satisfactory decompression of the lumbar spinal stenosis and tolerable clinical outcome. This approach is thought to be appropriate for elderly patients who have a greater surgical burden.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.844-853
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• 1990

We have performed 27 cases of orthotopic homologous cardiac transplantation using Korean mongrel dogs and one case of sham operation for the evaluation of harmful effect of cardiopulmonary bypass itself on the dog from April, 1989 to June, 1990. Our previous reports have already demonstrated basal hemodynamic and hematologic data on the canine homologous heart transplantation and the fundamental principles of transplantation of the heart. The mean body weight of recipients was 13.2$\pm$1.2kg with a rage of 11 ~ 15kg, and the hemodynamic and hematologic pictures were almost same as the result of previous reports from our hospital, except marked decrease in postoperative platelet count[from 3.18 $\pm$0.80x106/mm3 to 1.41$\pm$0 37x 106/mm3]. Mean survival time was 24.82$\pm$49.40 hours with the longest survival of 264 hours. Donor cardiectomy included coronary vasodilatation with diltiazem, potassium arrest, and the rapid cooling of the heart suspending in the specially designed ice-bath. Median sternotomy provided excellent exposure of the surgical field. 6 \ulcorner0 prolene suture was used for the anastomosis of both atrial cuffs and the great arteries, and we found the fact that stenosis, bleeding, thrombus formation around the anastomotic site could be decreased with the use of everted horizontal mattress suture techniques. Immunosuppression was done with a combination of lower dose Cyclosporin-A, Azathioprine, methyl-prednisolone, but our cases still showed too short survival to worry about graft rejection. Still poor was our quality control of experimental animal, we had much difficulties in postmortem evaluation of the dogs. Low cardiac output due to biventricular failure, intractable supraventricular or ventricular tachyarrhythmia, postoperative massive bleeding, sepsis were most frequent findings that could be thought as a cause of death. A few cases showed subendocardial patch hemorrhage in both ventricular cavity or atrial septum at autopsy, suggesting acute subendocardial infarction. Although our team overcome most of the technical problems of orthotopic heart transplantation, we should pile up further knowledges about donor heart preservation, quality control of animal, infection, rejection, the effect of the cardiopulmonary bypass to improve the results.