• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.96-102
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• 2020

Oral cancer surgery changes the morphologic characteristics of the human upper airway. These changes can affect the flow patterns. In this study, computational fluid dynamics (CFD) simulations with transient solver were performed to numerically investigate the air flows in the human upper airways depending oral cancer surgery. 3D reconstructed models were obtained from 2D CT images of one patient. For the boundary condition, the realistic breathing cycle of human was applied. The hydraulic diameters of cross-sections for post-surgical model are changed greatly along streamwise direction, so these variations can cause higher wall shear stress and flow disturbance compared to pre-surgical model. The recirculation flows observed in the protruding region result in the relatively large pressure drop. These results can be helpful to understand the flow variations after resection surgery of oral cancer.

• Korean Journal of Cleft Lip And Palate
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• v.6 no.2
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• pp.91-105
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• 2003

There are significant limitations in the precision of mandibular distraction in setting a desired occlusal and facial esthetic outcome. The purpose of this study is to present the simulation method for the distraction osteogenesis treatment planning. 3-D surgery simulation software programs V-works and V-Surgery(Cybermed, Seoul, Korea) were used from the 3D CT data in addition to the conventional data facial photography, panorama and cephalogram, dental cast model. We have utilized already for the various surgical procedures to get information preoperatively for the maxillofacial surgery like cancer localization and reconstructive surgery, orthognathic surgery and implant surgery in the department of Oral and Maxillofacial surgery, Seoul National University Hospital. On the software, bone cutting can be done at any place and any direction. Separated bone segment can be mobilized in all 3 dimensional direction. After the 3D simulation on the software program, mock surgery on the RP model can be performed. This planning method was applied to two hemifacial microsomia patients. With this protocol, we could simulate the movement of bony segment after maxillofacial distraction osteogenesis

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.2
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• pp.158-166
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• 2009

The application of CT with basis on 3 dimensional-reconstruction is getting more widely practiced. With the data obtained from cone-beam computed tomography(CBCT), not only the diagnosis of the patient with skeletal abnormality but also the virtual simulation of the orthognathic surgery were performed and its application would be popular in orthodontic field. We reported a case, a 19-year old man who was diagnosed mandibular prognathism and required orthognatic surgery. In this case, the virtual orthognathic surgery was simulated and surgical wafer was fabricated by using CBCT data. That wafer was applied the actual orthognathic surgery. After preoperative orthodontic treatment, we prepared surgery as follows. : (l)Acquisition of 3D image data, (2)Reconstruction of 3-dimensional virtual model, (3)Virtual model surgery, (4)Extraction of stere-olithographic image, (5)Check-up for occlusal interference, (6)Fabrication of surgical stent by stereolithography. Bilateral sagittal split ramus osteotomy was operated and used stereolithographic surgical stent. 1 month later, we superimposed CBCT datas of virtual surgery and that of actual surgery, and then compared the result. CT data's application for othognathic surgery yielded satisfactory outcomes.

• Parasites, Hosts and Diseases
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• v.54 no.2
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• pp.225-231
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• 2016

Human and animal alveolar echinococcosis (AE) are important helminth infections endemic in wide areas of the Northern hemisphere. Monitoring Echinococcus multilocularis viability and spread using real-time fluorescent imaging in vivo provides a fast method to evaluate the load of parasite. Here, we generated a kind of fluorescent protoscolices in vivo imaging model and utilized this model to assess the activity against E. multilocularis protoscolices of metformin (Met). Results indicated that JC-1 tagged E. multilocularis can be reliably and confidently used to monitor protoscolices in vitro and in vivo. The availability of this transient in vivo fluorescent imaging of E. multilocularis protoscolices constitutes an important step toward the long term bio-imaging research of the AE-infected mouse models. In addition, this will be of great interest for further research on infection strategies and development of drugs and vaccines against E. multilocularis and other cestodes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.4
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• pp.239-244
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• 2003

The common errors in preoperative treatment plan for the orthognathic surgery can be occurred during cast impression, cast mounting procedure with face-bow transfer, surgical stent fabrication, and so on. One of the most common errors exists during mounting process of the model on the articulator. Accurate mounting of dental casts to articulator should be achieved by transferring the 3-dimensional spatial relationship of the maxillary arch to an articulator. A face-bow is used for transfer this relationship to articulator, usually by relating the face-bow to a plane of reference of maxillary cast. The purpose of this study is evaluation of the accuracy of face-bow transferring of maxillary model to the articulator. The maxillary casts of thirty patients for orthognathic surgery were mounted on articulator with an face-bow instrument. The relationship of occlusal plane angle to Frankfort horizontal plane relations were compared the cephalogram with the cast-mounted articulator. As a result of this study, the significant difference between the maxillary occlusal planes angle in the cephalogram and articulator were found. The results were followed, 1. The mean occlusal plane angle in cast-mounted articulator was $13.5^{\circ}\;(SD{\pm}5.4)$. 2. The mean occlusal plane angle in cephalogram was $10.4^{\circ}\;(SD{\pm}4.3)$. 3. The mean difference of occlusal plane angle between cast-mounted articulator and cephalogram was $3.3^{\circ}\;(SD{\pm}4.6)$. According to the result, we should suggest that the occlusal plane angle to Frankfort plane in cast-mounted articulator is more steeper than that of cephalogram. And then, maxillofacial surgeon should try to get a more predictable result by suggesting the proper correction method and mounting the cast accurately.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.460-465
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• 2021

Background: Metastasis and recurrence of primary cancer are the main causes of cancer mortality. Disseminated tumor cells refer to cancer cells that cause metastasis from primary cancer to other organs. Several recent studies have suggested that circulating tumor cells (CTCs) are associated with the clinical stage, cancer recurrence, cancer metastasis, and prognosis. There are several methods of isolating CTCs from whole blood; in particular, using a membrane filtration system is advantageous due to its cost-effectiveness and availability in clinical settings. In this study, an animal model of lung cancer was established in nude mice using the human large cell lung cancer cell line H460. Methods: Six-week-old nude mice were used. The H460 lung cancer cell line was injected subcutaneously into the nude mice. Blood samples were obtained from the orbital area before cell line injection, 2 weeks after injection, and 2 weeks after tumor excision. Blood samples were filtered using a polycarbonate 12-well Transwell membrane (Corning Inc., Corning, NY, USA). An indirect immunofluorescence assay was performed with the epithelial cell adhesion molecule antibody. The number of stained cells was counted using fluorescence microscopy. Results: The average size of the tumor masses was 35.83 mm. The stained cells were counted before inoculation, 2 weeks after inoculation, and 2 weeks after tumor excision. Cancer cells generally increased after inoculation and decreased after tumor resection. Conclusion: The CTC detection method using the commercial polycarbonate 12-well Transwell (Corning Inc.) membrane is advantageous in terms of cost-effectiveness and convenience.

• Journal of International Society for Simulation Surgery
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• v.1 no.1
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• pp.16-18
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• 2014

The orbit has a very special anatomical structure. The complex anatomical structure should be restored when we encounter the patient with orbital wall fracture. Unless these specific anatomy were reconstructed well, the patient should suffer from various complications such enophthalmos, diplopia or orbital deformity. In addition, because the patient has a his own specific orbital shape, individualized approach will be necessary. The aim of this trial is to try to restore the original orbit anatomy as possible based on the mirrored three dimensional CT images based on the computer simulation. Preoperative computed tomography (CT) data were processed for the patient and a rapid prototyping (RP) model was produced. At the same time, the uninjured side was mirrored and superimposed onto the traumatized side, to create a mirror-image of the RP model. In order to restore the missing skipped images between the cuts of CT data because of the thinness of the orbital walls, we manipulated the DICOM data for imaging the original orbital contour using the preoperatively manufactured mirror-image of the RP model. And we fabricated Titanium-Medpor to reconstruct three-dimensional orbital structure intraoperatively. This prefabricated Titanium-Medpor was then inserted onto the defected orbital wall and fixed. Three dimensional approach based on the computer simulation turned out to be very successful in this patient. Individualized approach for each patient could be an ideal way to manage the traumatic patients in near future.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.725-732
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• 2011

Purpose: Skin grafting is one of the most commonly used methods in reconstructive plastic surgery field, but complications such as color change, contracture or hypertrophy are common problems. However, pathophysiology of the color change after skin graft is not yet determined and no animal model is established. Methods: Full thickness skin grafts were performed on the dorsum of C57BL/6 mice. Serial chronological gross inspection for color change and pigmentation were examined. Melanin pigments were traced by Fontana-Masson staining and semi-quantitative analysis was performed. In addition, immunohistochemical staining of S-100, Micropthalmia related Transcription Factor (MITF) and Melan-A antibodies were also performed to observe melanocytes and their changes. Results: After skin graft, color change and pigment spots were observed in the graft. Fontana-Masson staining showed melanin pigments in the epidermal and dermal layers in all mice. Immunohistochemistry staining to S-100, MITF, Melan-A antibodies showed melanocytes at the basal layer of epidermis and dermis. Conclusion: In conclusion, we have established an animal model for skin pigmentation after skin graft. We believe this study may be useful in understanding of the behavior of melanocytes after skin graft.

• The Korean Journal of Pain
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• v.23 no.3
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• pp.166-171
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• 2010

Background: Neuropathic pain resulting from diverse causes is a chronic condition for which effective treatment is lacking. The goal of this study was to test whether dexamethasone exerts a preemptive analgesic effect with bupivacaine when injected perineurally in the spared nerve injury model. Methods: Fifty rats were randomly divided into five groups. Group 1 (control) was ligated but received no drugs. Group 2 was perineurally infiltrated (tibial and common peroneal nerves) with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 3 was infiltrated with 0.4% bupivacaine (0.2 ml) and dexamethasone (0.8 mg) after surgery. Group 4 was infiltrated with normal saline (0.2 ml) and dexamethasone (0.8 mg) 10 minutes before surgery. Group 5 was infiltrated with only 0.4% bupivacaine (0.2 ml) before surgery. Rat paw withdrawal thresholds were measured using the von Frey hair test before surgery as a baseline measurement and on postoperative days 3, 6, 9, 12, 15, 18 and 21. Results: In the group injected preoperatively with dexamethasone and bupivacaine, mechanical allodynia did not develop and mechanical threshold forces were significantly different compared with other groups, especially between postoperative days 3 and 9 (P < 0.05). Conclusions: In conclusion, preoperative infiltration of both dexamethasone and bupivacaine showed a significantly better analgesic effect than did infiltration of bupivacaine or dexamethasone alone in the spared nerve injury model, especially early on after surgery.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2823-2828
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• 2012

Objective: To explore a new model of in-situ xenograft lymphangiogenesis of human colonic adenocarcinomas in nude mice. Method: On the basis of establishing subcutaneous xenograft lymphangiogenesis model of human colonic adenocarcinoms, in-situ xenografts were established through the in situ growth of the HT-29 human colonic adenocarcinoma cell line in nude mice. The numbers of lymphangiogenic microvessels, the expression of lymphatic endothelial cell markers lymphatic vessel endothelial hyaloronic acid receptor-1 (LYVE-1), D2-40 and the lymphatic endothelial growth factors vascular endothelial growth factor-C (VEGF-C), -D (VEGF-D) and receptor-3 (VEGFR-3) were compared by immunohistochemical staining, Western bolt and quantitative RT-PCR in xenograft in-situ models. Results: Some microlymphatics with thin walls, large and irregular or collapsed cavities and increased LMVD, with strong positive of LYVE-1, D2-40 in immunohistochemistry, were observed, identical with the morphological characteristics of lymphatic vessels and capillaries. Expression of LYVE-1 and D2-40 proteins and mRNAs were significantly higher in xenograpfts in-situ than in the negative control group(both P<0.01). Moreover, the expression of VEGF-C, VEGF-D and VEGFR-3 proteins and mRNAs were significantly higher in xenografts in-situ (both P<0.01), in conformity with the signal regulation of the VEGF-C,-D/VEGFR-3 axis of tumor lymphangiogenesis. Conclusions: In-situ xenografts of a human colonic adenocarcinoma cell line demonstrate tumor lymphangiogenesis. This novel in-situ animal model should be useful for further studying mechanisms of lymph node metastasis, drug intervention and anti-metastasis therapy in colorectal cancer.