• Title/Summary/Keyword: Model surgery

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Development of an experimental model for radiation-induced inhibition of cranial bone regeneration

  • Jung, Hong-Moon;Lee, Jeong-Eun;Lee, Seoung-Jun;Lee, Jung-Tae;Kwon, Tae-Yub;Kwon, Tae-Geon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.40
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    • pp.34.1-34.8
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    • 2018
  • Background: Radiation therapy is widely employed in the treatment of head and neck cancer. Adverse effects of therapeutic irradiation include delayed bone healing after dental extraction or impaired bone regeneration at the irradiated bony defect. Development of a reliable experimental model may be beneficial to study tissue regeneration in the irradiated field. The current study aimed to develop a relevant animal model of post-radiation cranial bone defect. Methods: A lead shielding block was designed for selective external irradiation of the mouse calvaria. Critical-size calvarial defect was created 2 weeks after the irradiation. The defect was filled with a collagen scaffold, with or without incorporation of bone morphogenetic protein 2 (BMP-2) (1 ㎍/ml). The non-irradiated mice treated with or without BMP-2-included scaffold served as control. Four weeks after the surgery, the specimens were harvested and the degree of bone formation was evaluated by histological and radiographical examinations. Results: BMP-2-treated scaffold yielded significant bone regeneration in the mice calvarial defects. However, a single fraction of external irradiation was observed to eliminate the bone regeneration capacity of the BMP-2-incorporated scaffold without influencing the survival of the animals. Conclusion: The current study established an efficient model for post-radiation cranial bone regeneration and can be applied for evaluating the robust bone formation system using various chemokines or agents in unfavorable, demanding radiation-related bone defect models.

Use of 3D Printing Model for the Management of Fibrous Dysplasia: Preliminary Case Study

  • Choi, Jong-Woo;Jeong, Woo Shik
    • Journal of International Society for Simulation Surgery
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    • v.3 no.1
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    • pp.36-38
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    • 2016
  • Fibrous dysplasia is a relatively rare disease but the management would be quite challenging. Because this is not a malignant tumor, the preservation of the facial contour and the various functions seems to be important in treatment planning. Until now the facial bone reconstruction with autogenous bone would be the standard. Although the autogenous bone would be the ideal one for facial bone reconstruction, donor site morbidity would be the inevitable problem in many cases. Meanwhile, various types of allogenic and alloplastic materials have been also used. However, facial bone reconstruction with many alloplastic material have produced no less complications including infection, exposure, and delayed wound healing. Because the 3D printing technique evolved so fast that 3D printed titanium implant were possible recently. The aim of this trial is to try to restore the original maxillary anatomy as possible using the 3D printing model, 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. And we molded Titanium mesh to reconstruct three-dimensional maxillary structure during the operation. This prefabricated Titanium-mesh implant was then inserted onto the defected maxilla and fixed. Three dimensional printing technique of titanium material based on the computer simulation turned out to be successful in this patient. Individualized approach for each patient could be an ideal way to restore the facial bone.

Reconstruction of temporal hollowing deformities using silicone implants made using a toy-clay model: a report of three cases

  • Kim, Min Wook;Kim, Seung Hyun;Nam, Su Bong;Lee, Jae Woo;Jeong, Dae Kyun;Kim, Young Ha
    • Archives of Craniofacial Surgery
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    • v.23 no.1
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    • pp.34-38
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    • 2022
  • Severe temporal hollowing deformities can occur in patients who undergo craniectomy after intracranial hemorrhage. Reconstruction surgery for cosmetic purposes using silicone implants in patients with temporal hollowing deformities after craniectomy is advantageous because the procedure is simple and rapid, with a short recovery time, resulting in lower overall treatment costs. Of paramount importance, this option yields highly satisfactory results for patients. The authors present three cases of simple and fast surgery using silicone implants where highly satisfactory outcomes were obtained.

Lack of Association between the hOGG1 Ser326Cys Polymorphism and Gastric Cancer Risk: a Meta-analysis

  • Li, Bai-Rong;Zhou, Guo-Wu;Bian, Qi;Song, Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1145-1149
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    • 2012
  • Aim: To clarify any association between the hOGG1 Ser326Cys polymorphism and susceptibility to gastric cancer. Methods: A meta-analysis based on 11 eligible case-control studies involving 5,107 subjects was carried out to summarize the data on the association between hOGG1 Ser326Cys polymorphism and gastric cancer risk. Results: No association was found between hOGG1 Ser326Cys polymorphism and gastric cancer risk (dominant model: OR = 0.95, 95% CI: 0.83-1.09, p = 0.486, ph (p values for heterogeneity) = 0.419; additive model: OR = 1.02, 95% CI: 0.81-1.30, p = 0.850, ph = 0.181; recessive model: OR = 1.09, 95% CI: 0.80-1.48, p = 0.586, ph = 0.053). Subgroup analysis based on ethnicity (Asian and Caucasian) and smoking status (ever smoker and never smoker) did did notpresent any significant association. Sensitivity analysis did not perturb the results. Conclusions: This study strongly suggested there might be no association between the hOGG1 Ser326Cys polymorphism and gastric cancer risk. However, larger scale studies are needed for confirmation.

Hepatoprotective effect of ultrasonicated ginseng berry extract on a rat mild bile duct ligation model

  • Nam, Yoonjin;Ko, Sung Kwon;Sohn, Uy Dong
    • Journal of Ginseng Research
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    • v.43 no.4
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    • pp.606-617
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    • 2019
  • Background: The Panax ginseng berry extract (GBE) is well known to have an antidiabetic effect. The aim of this study is to evaluate and investigate the protective effect of ultrasonication-processed P. ginseng berry extract (UGBE) compared with GBE on liver fibrosis induced by mild bile duct ligation (MBDL) model in rats. After ultrasonication process, the composition ratio of ginsenoside in GBE was changed. The component ratio of ginsenosides Rh1, Rh4, Rg2, Rg3, Rk1, Rk3, and F4 in the extract was elevated. Methods: In this study, the protective effect of the newly developed UGBE was evaluated on hepatotoxicity and neuronal damage in MBDL model. Silymarin (150 mg/kg) was used for positive control. UGBE (100 mg/kg, 250 mg/kg, 500 mg/kg), GBE (250 mg/kg), and silymarin (150 mg/kg) were orally administered for 6 weeks after MBDL surgery. Results: The MBDL surgery induced severe hepatotoxicity that leads to liver inflammation in rats. Also, the serum ammonia level was increased by MBDL surgery. However, the liver dysfunction of MBDL surgery-operated rats was attenuated by UGBE treatment via myeloid differentiation factor 88-dependent Toll-like receptor 4 signaling pathways. Conclusion: UGBE has a protective effect on liver fibrosis induced by MBDL in rats through inhibition of the TLR4 signaling pathway in liver.

The Correction of Mild Mandibular Prognathism Using Mandibular Anterior Segmental Osteotomy (하악 전방분절 절골술을 이용한 경미한 하악전돌증의 교정)

  • Choi, Jae Ho;Choe, Joon;Kim, Young Hwan;Yun, Sung Ho;Kim, Young Soo;Choi, Young Woong
    • Archives of Plastic Surgery
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    • v.34 no.6
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    • pp.777-784
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    • 2007
  • Purpose: For a minor degree of mandibular prognathism, mandibular anterior segmental osteotomy (ASO), usually extracting the bilateral premolars, has been performed frequently to correct malocclusion of the anterior teeth. Preoperative planning using cephalometry and a dental model is very important for such a orthognathic surgery. Depending on the specific preoperative mock surgery with the dental model, ASO, with ipsilateral unitooth extraction, is defined to be feasible and performed for ten patients. The comparisons of its preoperative and postoperative analysis of clinical photographs, dental casts, and lateral cephalograms, for soft tissue profiles, skeletal and dental relationships are described in the following, and its clinical applications are noted. Methods: From March 1, 2004, to March 31, 2006, We performed 10 mandibular ASO by extraction of ipsilateral unitooth to improve their lower facial profiles and the lip relationships. Patient age ranged from 19 to 33 years, with a mean age of 25.6 years. Two were males and eight were females. Results: All patients were satisfied with aesthetic and occlusal changes postoperatively. Significant and persistent decrease in the SNB and interincisal angle were observed in the postoperative cephalometries. The soft tissue profiles also were improved and near Ricketts's esthetic line. Other combined procedures include nine genioplasties, two rhinoplasties, and one blepharoplasty. One patient complained of transient unilateral inferior mental nerve paresthesia. There were no other significant complications or relapses throughout the follow-up period(6-20 months). Conclusion: Mandibular ASO, extracting the ipsilateral unitooth, was performed for ten patients to correct mild mandibular prognathism. The amount of setback of the mandibular anterior portion was 2 to 3 mm, and satisfactory results were obtained combined with genioplasties.

The effects of optimizing blood inflow in the pedicle on perforator flap survival: A pilot study in a rat model

  • Olariu, Radu;Moser, Helen Laura;Lese, Ioana;Sabau, Dan;Georgescu, Alexandru Valentin;Grobbelaar, Adriaan Ockert;Constantinescu, Mihai Adrian
    • Archives of Plastic Surgery
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    • v.47 no.3
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    • pp.209-216
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    • 2020
  • Background Perforator flaps have led to a revolution in reconstructive surgery by reducing donor site morbidity. However, many surgeons have witnessed partial flap necrosis. Experimental methods to increase inflow have relied on adding a separate pedicle to the flap. The aim of our study was to experimentally determine whether increasing blood flow in the perforator pedicle itself could benefit flap survival. Methods In 30 male Lewis rats, an extended posterior thigh perforator flap was elevated and the pedicle was dissected to its origin from the femoral vessels. The rats were assigned to three groups: control (group I), acute inflow (group II) and arterial preconditioning (group III) depending on the timing of ligation of the femoral artery distal to the site of pedicle emergence. Digital planimetry was performed on postoperative day (POD) 7 and all flaps were monitored using laser Doppler flowmetry perioperatively and postoperatively in three regions (P1-proximal flap, P2-middle of the flap, P3-distal flap). Results Digital planimetry showed the highest area of survival in group II (78.12%±8.38%), followed by groups III and I. The laser Doppler results showed statistically significant higher values in group II on POD 7 for P2 and P3. At P3, only group II recorded an increase in the flow on POD 7 in comparison to POD 1. Conclusions Optimization of arterial inflow, regardless if performed acutely or as preconditioning, led to increased flap survival in a rat perforator flap model.

Clinicopathological Features and Survival of Patients with Gastric Cancer with a Family History: a Large Analysis of 2,736 Patients with Gastric Cancer

  • Jeong, Oh;Jung, Mi Ran;Park, Young Kyu;Ryu, Seong Yeob
    • Journal of Gastric Cancer
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    • v.17 no.2
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    • pp.162-172
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    • 2017
  • Purpose: Previous studies indicated conflicting results regarding the prognosis of gastric cancer with a family history (FHX). This study aimed to determine the clinicopathological features and survival of patients with gastric cancer with a FHX. Materials and Methods: We reviewed 2,736 patients with gastric cancer who underwent surgery between 2003 and 2009. The prognostic value of a FHX was determined in the multivariate model after adjusting for variables in the Asian and internationally validated prognostic models. Results: Of the patients, 413 (15.1%) had a FHX of gastric cancer. The patients with a FHX were younger (58.1 vs. 60.4 years; P<0.001) than the patients without a FHX. There were no significant differences in the histopathological characteristics between the 2 groups. A FHX was associated with a better overall survival (OS) rate only in the stage I group (5-year survival rate, 95% vs. 92%; P=0.006). However, the disease-specific survival (DSS) rate was not significantly different between the 2 groups in all stages. The multivariate model adjusted for the variables in the Asian and internationally validated prognostic models revealed that FHX has no significant prognostic value for OS and DSS. Conclusions: The clinicopathological features and survival of the patients with gastric cancer with a FHX did not significantly differ from those of the patients without a FHX.