• Journal of Chest Surgery
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• 제32권11호
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• pp.978-983
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• 1999

Background: Complement activation with transpulmonary leukocyte sequestration is considered a main mediator leading to ischemia-reperfusion lung(I-R) injury. We studied the role of leukocytes in the formation of I-R injury in ovine cardiopulmonary bypass(CPB) model with a membrane oxygenator. Material and Method: Five sheep were used. CPB circuitry consisted of a roller pump(American Optical Corp., Greenwich, CT, USA) and a membrane oxygenator(UNIVOX-IC, Bentley, Baxter Health Corp, Irvine, CA, USA). The CPB time was fixed at 120 min. Ten minutes after the start of CPB, total CPB was established. Thereafter a total CPB of 100 min was performed, followed by another 10 min of partial CPB. The CPB was discontinued and the animals were fully recovered. For measuring left and right atrial leukocyte counts, blood samples were taken before thoracotomy, 5 min and 109 in after the start of CPB, and 30 min and 120 min after weaning. C3a was measured before thoracotomy, 109 min after the start of CPB, and 30 min and 120 min after weaning. Plasma malondialdehyde(MDA) was checked before thoracotomy, 109 min after the start of CPB, and 30 min after weaning. One to two grams of lung tissue were taken for water content measurement before thoracotomy, 109 min after the start of CPB, and 30 min after weaning. Lung biopsy specimens were examined by light and electron microscopy. Result: Of 5 animals, 4 survived the experimental procedures. Of these, 3 animals survived on a long-term basis. No significant differences in transpulmonary gradients of leukocyte were found and no significant complement activation was expressed by C3a levels. MDA level did not show significant changes related to lung reperfusion despite an increase after the start of CPB. On both light and electron microscopic examinations, mild to moderate acute lung change was observed. Interstitial edema, leakage of erythrocytes into the alveolar space and endothelial cell swelling were the main findings. Water content of the lung showed a slight increase after the start of CPB, but there was no statistical significance. Conclusion: These findings indicate that ischemia-repersusion lung injury may not be from complement activation-leukocyte sequestration but from another source of oxygen free radicals related to CPB.

• 대한두개안면성형외과학회지
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• 제11권1호
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• pp.65-68
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• 2010

Purpose: Dermoid cysts are benign neoplasms that are derived from both ectoderm and mesoderm. Approximately 7 percent of all dermoid cysts occur in the head and neck, as most common sites are the lateral ends of the eyebrows, the midline in the nasal root and neck. Rarely they can be found in the frontal sinus, temporal bone, maxilla and the floor of the mouth. Dermoid cysts in the temporal fossa are extremely rare. We experienced a characteristic dermoid cyst that occupied the temporal fossa. Methods: A 16-year-old man had a progressive enlarging mass on the left eyebrow. Computerized tomographic scan showed a bulging mass in the temporal fossa, and it had the density similar to that of fat. The size of the mass was $3{\times}3{\times}2cm$, and it was composed of high density of fat with clear margin. There was no bony invasion, but the mass was fixed on bone. Results: We performed the surgery through coronal incision under general anesthesia. Because the mass was closely connected with temporal fat pads, we removed this mass with some portion of temporal fat pads, avoiding damage to the facial nerve. The postoperative course was ordinary without complication. Conclusion: The reports about dermoid cyst on the temporal fossa is uncommon. However, if there is a mass in the temporal fossa which has the density similar to that of fat in CT scan, we should consider the possibility of dermoid cyst. We suggest that excision through coronal incision with bewaring temporal fat pad can induce good result.

• 대한의용생체공학회:의공학회지
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• 제29권6호
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• pp.451-456
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• 2008

Total knee arthroplasty(TKA) using computer-assisted navigation has been increased in order to improve the accuracy of femoral and tibial components implantation. Recently, a few clinical studies have reported on the femoral stress fracture after TKA using computer-assisted navigation. The purpose of this study is to investigate the stress concentration around the femoral pin-hole for different pin-hole diameter, the modes of pin penetration by finite element analysis to understand the effects of pin-hole parameters on femoral stress fracture risk. A three-dimensional finite element model of a male femur was reconstructed from 1 mm thick computed tomography(CT) images. The bone was rigidly fixed to a 25 mm above the distal end and 1500 N of axial compressive force and 12 Nm of axial torsion were applied at the femoral head. For all cases, transcortical pin penetration mode showed the highest stress fracture risk and unicortical pin penetration mode showed the lowest stress concentration. Pin-hole diameter increased the stress concentration, but pin number did not increase the stress dramatically. The results of this study provided a biomechanical guideline for pin-hole fracture risk of the computer navigated TKA.

• 대한두개안면성형외과학회지
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• 제9권2호
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• pp.55-61
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• 2008

Purpose: The purpose of this study is to evaluate the effectiveness of internal fixation method of $Medpor^{(R)}$ implant with $BioSorb^{TM}FX$ screw which is used for prevention of enophthalmos in posteriorly extended large orbital floor fracture. Methods: From Jun. 1997 to Dec. 2007, 21 patients who were diagnosed with posteriorly extended large orbital floor fractures were classified into two groups. One group(n=11) had undergone reduction surgery with regular $Medpor^{(R)}$ sheets without any fixation method, while the other group(n=10) had their $Medpor^{(R)}$ sheets fixed with the $BioSorb^{TM}FX$ screws. The two groups were evaluated by comparison of their enophthalmos degree and effectiveness. Results: In the non-fixation group, six patients had enophthalmos preoperatively and three of them showed persistent enophthalmos postoperatively. In postoperative CT examination, displacement of $Medpor^{(R)}$ implant with soft tissue impaction into maxillary sinus was observed in the patients. In the screw fixation group, three patients had enophthalmos preoperatively, but none of them suffer from complication such as residual enophthalmos, soft tissue impaction, muscle entrapment or optic nerve compression postoperatively. Conclusion: Internal fixation method of $Medpor^{(R)}$ implant with $BioSorb^{TM}FX$ screw on the medial surface of orbital floor provides firm stabilization of implants and surrounding soft tissues and can be an effective option especially when postoperative implant displacement or malposition was expected.

• The Journal of Advanced Prosthodontics
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• 제6권4호
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• pp.253-258
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• 2014

PURPOSE. To compare marginal and internal gaps of zirconia substructure of single crowns with those of three-unit fixed dental prostheses. MATERIALS AND METHODS. Standardized Co-Cr alloy simulated second premolar and second molar abutments were fabricated and subsequently duplicated into type-III dental stone for working casts. After that, all zirconia substructures were made using $Lava^{TM}$ system. Marginal and internal gaps were measured in 2 planes (mesial-distal plane and buccal-palatal plane) at 5 locations: marginal opening (MO), chamfer area (CA), axial wall (AW), cusp tip (CT) and mid-occlusal (OA) using Replica technique. RESULTS. There were significant differences between gaps at all locations. The $mean{\pm}SD$ of marginal gap in premolar was $43.6{\pm}0.4{\mu}m$ and $46.5{\pm}0.5{\mu}m$ for single crown and 3-unit bridge substructure respectively. For molar substructure the $mean{\pm}SD$ of marginal gap was $48.5{\pm}0.4{\mu}m$ and $52.6{\pm}0.4{\mu}m$ for single crown and 3-unit bridge respectively. The largest gaps were found at the occlusal area, which was $150.5{\pm}0.5{\mu}m$ and $154.5{\pm}0.4{\mu}m$ for single and 3-unit bridge premolar substructures respectively and $146.5{\pm}0.4{\mu}m$ and $211.5{\pm}0.4{\mu}m$ for single and 3-unit bridge molar substructure respectively. CONCLUSION. Independent-samples t-test showed significant differences of gap in zirconia substructure between single crowns and three-unit bridge (P<.001). Therefore, the span length has the effect on the fit of zirconia substructure that is fabricated using CAD/CAM technique especially at the occlusal area.

• 대한의용생체공학회:의공학회지
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• 제37권2호
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• pp.68-74
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• 2016

In this study, we investigated the rotational characteristics which were comprised of directionality and linearity of target registration error (TRE) as a study in advance to enhance the accuracy of contour-based registration in neuronavigation. For the experiment, two rigid head phantoms that have different faces with specially designed target frame fixed inside of the phantoms were used. Three-dimensional coordinates of facial surface point cloud and target point of the phantoms were acquired using computed tomography (CT) and 3D scanner. Iterative closest point (ICP) method was used for registration of two different point cloud and the directionality and linearity of TRE in overall head were calculated by using 3D position of targets after registration. As a result, it was represented that TRE had consistent direction in overall head region and was increased in linear fashion as distance from facial surface, but did not show high linearity. These results indicated that it is possible for decrease TRE by controlling orientation of facial surface point cloud acquired from scanner, and the prediction of TRE from surface registration error can decrease the registration accuracy in lesion. In the further studies, we have to develop the contour-based registration method for improvement of accuracy by considering rotational characteristics of TRE.

• Journal of Chest Surgery
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• 제29권6호
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• pp.621-625
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• 1996

"중엽증후군"의 용어는 Grahaml)등에,의해 처음 기술되어졌으며 대개 비후된 림프절에 의해 기관지 가 외부적으로 압박되 어 발생된다고 하였다. 환자들은 거의 증상이 없을 수 있으나 가장 흔한 발현 증상 은 기침, 호흡 곤란, 반복되는 발열, 객혈, 그리고 흥통 등이다. 진단방법은 흉부 X선, 기관지경검사, 기 관지조영술, 흉부컴퓨터단층될영 등이며 대개 공기가 없이 압축된 중엽이 중요한 소견이다. 본 저자들은 1990년 3월에서 1995년 5월까지 15례의 중엽증후군을 경 험하였으며 그 중 11례에서 수술 적 치료를 시행하였다. 중엽 증후군의 환자에서 수술적용은 악성 종양이 의심되거나,비가역적 기관지 확장증,기관지협착증,약물 치료에 호전이 없는 경우, 치료후 반복되는 감염 등의 경우에 시행하였다. 수술은 중엽절제술 8례,중엽 및 하엽절제술2례,상엽 및 중엽절제술 1례를시술하였다. 수술후 병리조 직소견상 결핵 6례, 만성감염 3례, 악성 종양 1례, 국소적 출혈 1례의 소견을 보였다 술후 합병증은 2례에서 발생하였으며,그 중 1례에서 술후 폐허탈, 1례에서 간장장애를 경험하였으며 치유되었다.였으며 치유되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.5.1-5.8
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• 2018

Background: The objective of this study was to evaluate the influence of masticatory muscle injection of botulinum toxin type A (BTX-A) on the growth of the mandibular bone in vivo. Methods: Eleven Sprague-Dawley rats were used, and BTX-A (n = 6) or saline (n = 5) was injected at 13 days of age. All injections were given to the right masseter muscle, and the BTX-A dose was 0.5 units. All of the rats were euthanized at 60 days of age. The skulls of the rats were separated and fixed with 10% formalin for micro-computed tomography (micro-CT) analysis. Results: The anthropometric analysis found that the ramus heights and bigonial widths of the BTX-A-injected group were significantly smaller than those of the saline-injected group (P < 0.05), and the mandibular plane angle of the BTX-A-injected group was significantly greater than in the saline-injected group (P < 0.001). In the BTX-A-injected group, the ramus heights II and III and the mandibular plane angles I and II showed significant differences between the injected and non-injected sides (P < 0.05). The BTX-A-injected side of the mandible in the masseter group showed significantly lower mandibular bone growth compared with the non-injected side. Conclusion: BTX-A injection into the masseter muscle influences mandibular bone growth.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.663-666
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• 2009

Purpose: Primary malignant lymphomas of the salivary glands are uncommon. The parotid gland was most frequently involved, followed by the submandibular gland, minor salivary gland and sublingual gland. The most common subtype is mucosa - associated lymphoid tissue(MALT) lymphoma. We experienced a case of salivary MALT lymphoma involving parotid gland duct, so report a case with a review of the literature. Methods: A 65 year old female presented with a palpable mass on the left side of her cheek. There was no clinical or laboratory evidence of pre - existing autoimmune disease. Preoperative facial and neck CT with contrast showed $2.1{\times}1.7cm$ sized, ill defined, homogeneous low density mass near left masseter muscle, and no evidence of other enlarged lymph nodes. Results: At operation, a yellowish oval shaped mass was found slightly adhered to middle portion of the parotid gland duct, meaduring $2{\times}1.5{\times}0.7cm$. Microscopic finding showed that centrocyte - like cells, monocyte B cells and plasma cells were diffusely infiltrated. Immunophenotyping was preformed on fixed section. The majority of the small cells were immunoreactive for the B cell marker CD20. Based on the typical histological findings supported by immunostaining, the mass was defined as MALT lymphoma. Conclusion: We report that very rare case of MALT lymphoma involving parotid gland duct in 65 year old female patient was experienced with clinical characteristics, histologic features and references.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권5호
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• pp.382-387
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• 2021

Objectives: Zygomatic complex (ZMC) fractures comprise up to 40% of all facial fractures. Misaligned bone fragments and misplaced fixation hardware traditionally detected postoperatively on plain radiographs of the skull might require re-operation. The intraoperative O-Arm (Medtronic, USA) is a three-dimensional (3D) computed tomographic imaging system. Materials and Methods: This retrospective single-center study evaluated the utility of O-Arm scanning during corrective surgeries for ZMC and zygomatic arch (ZA) fractures from 2018 to 2020. Three females and 16 males (mean age, 31.52 years; range, 22-48 years) were included. Fracture instability (n=6) and facial deformity (n=15) were the most frequent indications for intraoperative 3D O-Arm scan. Results: The images demonstrated that all fracture lines were properly reduced and fixed. Another scan performed at the end of the fixation or reduction stage, however, revealed suboptimal results in five of the 19 cases, and further reduction and fixation of the fracture lines were required. Conclusion: Implementation of an intraoperative O-Arm system in ZMC and ZA fracture surgeries assists in obtaining predictable and accurate results and obviates the need for revision surgeries. The device should be considered for precise operations such as ZMC fracture repairs.