• Journal of International Society for Simulation Surgery
• /
• v.1 no.2
• /
• pp.90-94
• /
• 2014

Reconstruction of the mandible after ablative oral cancer surgery requires esthetic and functional rehabilitation. Restoring facial symmetry and dentition need accurate preoperative surgical planning and meticulous surgical technique. Free fibular flap is most useful tools to reconstruct mandible because of its adequate length and height, simultaneous harvest of soft and hard tissues and placing dental implants. In this case report, recurred squamous cell carcinoma in the right mandible had been resected and free fibular flap was utilized for mandible reconstruction using 3D rapid prototype. Simulation surgery before dental implant placement has been performed for esthetic and functional prosthodontics.

• Advances in biomechanics and applications
• /
• v.1 no.4
• /
• pp.279-292
• /
• 2014

This paper presents some simulations of fluxes and pressures in the coronary network, in the case of very severe coronary disease (several stenoses on the left branches and total occlusion of the right coronary artery). In that case, coronary artery bypass graft surgery is the commonly performed procedure. However, the success of the intervention depends on many factors. Modeling of the coronary circulation is thus important since it can help to understand the influence of all these factors on the coronary haemodynamics. We previously developed an analog electrical model that includes the eventual presence of collateral flows, and can describe the different revascularization strategies (two grafts, three grafts, ...). The aim of the present work is to introduce in our simulations the time-dependence of the coronary microvascular resistances, in order to better represent the effect of the systolic ventricular contraction (which induces an elevation of the resistances because the vessels are squeezed).

• Journal of Magnetics
• /
• v.18 no.2
• /
• pp.142-149
• /
• 2013

We aim to monitor vascularization of early bone perfusion following rabbit lumbar intertransverse bone graft fusion surgery using magnetic resonance imaging assessment. Correlation with graft survival status was evaluated by histological method. Experimental animals were randomly divided into three groups and the model was established by operating bilateral lumbar intertransverse bone graft with different types of bone graft substitute material. The lumbar intertransverse area of three groups of rabbits was scanned via MRI. In addition, histological examinations were performed at the $6^{th}$ week after surgery and the quantitative analysis of the osteogenesis in different grafted area was carried out by an image analysis system. The MRI technique can be used for early postoperative evaluation of vascularized bone graft perfusion after transplantation of different bone materials, whereas histological examination allows direct visualization of the osteogenesis process.

• Journal of Chest Surgery
• /
• v.50 no.3
• /
• pp.144-152
• /
• 2017

Background: The ubiquitin-proteasome system (UPS) is an important pathway of proteolysis in pathologic hypertrophic cardiomyocytes. We hypothesize that MG132, a proteasome inhibitor, might prevent hypertrophic cardiomyopathy (CMP) by blocking the UPS. Nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) and androgen receptor (AR) have been reported to be mediators of CMP and heart failure. This study drew upon pathophysiologic studies and the analysis of $NF-{\kappa}B$ and AR to assess the cardioprotective effects of MG132 in a left ventricular hypertrophy (LVH) rat model. Methods: We constructed a transverse aortic constriction (TAC)-induced LVH rat model with 3 groups: sham (TAC-sham, n=10), control (TAC-cont, n=10), and MG132 administration (TAC-MG132, n=10). MG-132 (0.1 mg/kg) was injected for 4 weeks in the TAC-MG132 group. Pathophysiologic evaluations were performed and the expression of AR and $NF-{\kappa}B$ was measured in the left ventricle. Results: Fibrosis was prevalent in the pathologic examination of the TAC-cont model, and it was reduced in the TAC-MG132 group, although not significantly. Less expression of AR, but not $NF-{\kappa}B$, was found in the TAC-MG132 group than in the TAC-cont group (p<0.05). Conclusion: MG-132 was found to suppress AR in the TAC-CMP model by blocking the UPS, which reduced fibrosis. However, $NF-{\kappa}B$ expression levels were not related to UPS function.

• The Journal of Korean Physical Therapy
• /
• v.21 no.3
• /
• pp.95-102
• /
• 2009

Purpose: This study evaluates MCP-1 expression in the dorsal horn of a rat model of lumbar disc herniation by an autograft of the nucleus pulposus to the spinal nerve. Methods: After a coccygeal nucleus pulposus graft to the left $5^{th}$ lumbar spinal nerve, proximal to dorsal root ganglion, mechanical allodynia and thermal hyperalgesia were assessed 1 day before surgery, and 1, 10, 20, 30 days after surgery. The mRNA of MCP-1 in the dorsal horn was assessed by real time PCR to compare the temporal pattern of neuropathic pain of the lumbar disc herniation model. Results: In the ipsilateral side of the lumbar disc herniation models, mechanical allodynia and thermal hyperalgesia reached a maximum at 10 days after surgery with significant difference from the control group. Pain was also provoked in the contralateral side of the lumbar disc herniation models with less intensity than the ipsilateral side. The level of MCP-1 mRNA expression in the dorsal horn reached a peak at 20 days after surgery. Conclusion: Mechanical allodynia and thermal hyperalgesia was induced by nucleus pulposus in a rat lumbar disc herniation model, similar to a previously reported peripheral nerve injury model. The level of MCP-1 expression was higher in the dorsal horn of the ipsilateral and contralateral sides. These results suggest that MCP-1 might play a role in the maintenance of neuropathic pain.

• Advances in pediatric surgery
• /
• v.6 no.1
• /
• pp.1-9
• /
• 2000

Despite of advances in perinatal management and treatment modalities congenital diaphragmatic hernia(CDH) remains a frustrating problem. Although the sheep has proven to be a reliable experimental model for the production of intrauterine CDH, the rabbit may have some advantages. These include lower cost, smaller body size, year-round availability, high number of fetuses per pregnancy, and short gestational period. To evaluate the feasibility of the rabbit model of CDH, twenty-seven pregnant New Zealand rabbits were utilized. Hysterotomy and an operative procedure for creating a diaphragmatic defect on gestational day 24 or 25, in two fetuses of each pregnant rabbit were performed. In one fetus of one cornu of the uterus, the left fetal diaphragm was excised through an open thoracotomy(DH group). In another fetus in the other cornu, CDH was created and the trachea clipped(Surgiclip, USSC, Norwalk, Conn., USA) (TL group). Delivery was by Cesarean section on 30 days of gestation. Among twenty- seven pregnant rabbits, 12 in the DH group and eight in the TL group were born alive. The most common herniated organ was the left lobe of the liver. In thee DH group, the lungs were hypoplastic with decreased lung weight/body weight ratio, reduced numbers of alveoli, thicker media of the pulmonary arteries, and immature alveoli. In TL group, the alveoli were more mature and did not differ from the control animals. In conclusion, (1) pulmonary hypoplasia develops in the fetal rabbit diaphragmatic hernia model and (2) simultaneous tracheal ligation prevents pulmonary hypoplasia.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.39
• /
• pp.16.1-16.6
• /
• 2017

Background: Mandibular reconstruction is performed after segmental mandibulectomy, and precise repositioning of the condylar head in the temporomandibular fossa is essential for maintaining preoperative occlusion. Methods: In cases without involvement of soft tissue around the mandibular bone, the autopolymer resin in a soft state is pressed against the lower border of the mandible and buccal and lingual sides of the 3D model on the excised side. After hardening, it is shaved with a carbide bar to make the proximal and distal parts parallel to the resected surface in order to determine the direction of mandibular resection. On the other hand, in cases that require resection of soft tissue around the mandible such as cases of a malignant tumor, right and left mandibular rami of the 3D model are connected with the autopolymer resin to keep the preoperative position between proximal and distal segments before surgical simulation. The device is made to fit the lower border of the anterior mandible and the posterior border of the mandibular ramus. The device has a U-shaped handle so that adaptation of the device will not interfere with the soft tissue to be removed and has holes to be fixed on the mandible with screws. Results: We successfully performed the planned accurate segmental mandibulectomy and the precise repositioning of the condylar head by the device. Conclusions: The present technique and device that we developed proved to be simple and useful for restoring the preoperative condylar head positioning in the temporomandibular fossa and the precise resection of the mandible.

• Journal of International Society for Simulation Surgery
• /
• v.1 no.1
• /
• pp.23-26
• /
• 2014

The aim of this report is to evaluate accuracy using3D surgical simulationand digitally printedwafer in orthognathic surgery. 22-year-old female was diagnosed with mandibular prognathism and apertognathia based on 3D diagnosis using CT. Digital dentition images were taken by laser scanning from dental cast, and each STL images were integrated into one virtual skull using simulation software. Digitalized intermediate wafer was manufactured using CAD/CAM software and 3D printer, and used to move maxillary segment in real patient. Constructed virtual skull from 1 month postoperative CT scan was superimposedinto simulated virtual model to reveal accuracy. Almost maxillo-mandibular landmarks were placed in simulated position within 1 mm differences except right coronoid process. Thus 3D diagnosis, surgical simulation, and digitalized wafer could be useful method to orthognathic surgery in terms of accuracy.

• Archives of Craniofacial Surgery
• /
• v.10 no.2
• /
• pp.71-75
• /
• 2009

Purpose: Recently, orbital wall fracture is common injuries in the face. Facial CT is essential for the accurate diagnosis and appropriate treatment to reconstruct of the orbital wall. The objective of this study was to report the method for accurate measurement of area and shape of the bony defect in the blow-out fractures using facial CT in prior to surgery. Methods: The authors experienced 46 cases of orbital wall fractures and examined for diplopia, sensory disturbance in the area of distribution of the infraorbital nerve, and enophthalmos in the preoperation and followed 1 months after surgery, from August 2007 to May 2008. Bony defect was predicted by measuring continuous defect size from 3 mm interval facial CT. Copying from the defect model (template), we reconstructed orbital wall with resorbable sheet (Inion $CPS^{(R)}$ Inion Oy, Tampere, Finland). Results: One months after surgery using this method, 26 (100%) of the 26 patients improved in the diplopia and sensory disturbance in the area of distribution of the infraorbital nerve. Also 8 (72.7%) of the 11 patients had enophthalmos took favorable turn. Conclusion: This accurate and time-saving method is practicable for determining the location, shape and size of the bony defect. Using this method, we can reconstruct orbital wall fracture fastly and precisely.

• Archives of Plastic Surgery
• /
• v.35 no.4
• /
• pp.367-372
• /
• 2008

Purpose: Prevention of acute rejection in skin allografts without continuous immunosuppression lacks reports in worldwide literature. Needs for chronic immunosuppression preclude the use of tissue allograft as a routine surgical reconstructive option. Recently dendritic cells(DC) gained considerable attention as antigen presenting cells that are also capable of immunologic tolerance induction. This study assesses the effects of alloantigen-pulsed dendritic cells in induction of survival increase in a rat skin allograft model. Methods: Recipient-derived dendritic cells were harvested from rat whole blood and cultured with GM-CSF(200 ng/mL) and IL-4(8 ng/mL) for 2 weeks. Then donor-specific alloantigen pulsed dendritic cells were reinjected into tail vein before skin graft. The rat dorsal skin allografts were transplanted in 5 subgroups. Groups: I) untreated, II) anti-lymphocyte serum(ALS, 0.5 mL), III) FK-506(2 mg/kg), IV) DCp, VI) DCp and FK-506. Graft appearance challenges were assessed postoperatively. Results: The group V(DC and FK-506 treated) showed longest graft survival rate(23.5 days) than other groups; untreated(5.8 days), ALS(7.2 days), FK-506 (17.5 days), DCp(12.2 days). Conclusion: Donor antigen pulsed host dendritic cell combined with short-term immunosuppression prolong skin allograft survival and has potential therapeutic application for induction of donor antigen specific tolerance.