• Archives of Plastic Surgery
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• v.37 no.4
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• pp.461-464
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• 2010

Purpose: Blepharoptosis can result from either congenital or acquired causes. Blow out fracture or facial bone fracture including blow out fracture can be one of the causes. Authors experienced 3 cases of severe blepharoptosis after blow out fracture treated only with observation after reduction of associated fracture. Methods: Reconstruction of orbital wall was conducted on all cases diagnosed as blow out fracture using 3 dimensional computed tomography, and conservative treatment was done on accompanying severe blepharoptosis. Results: At the time of injury, all cases showed severe blepharoptosis requiring frontalis muscle transfer for correction. But blepharoptosis was recovered in an average of 18 weeks without any surgical procedure except reconstruction of orbital wall. Conclusion: Once Blepharoptosis occurred after blow out fracture, thorough evaluation must be done at first. If definitive cause of blepahroptisis cannot be found as authors' cases, injury of oculomotor nerve may result in blepharoptosis. So, as for blepharoptosis after blow out fracture, conservative treatment following reconstruction of fractured orbital wall can be one of good management.

• Geomechanics and Engineering
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• v.37 no.4
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• pp.323-339
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• 2024

If the pressure exerted on the face of a tunnel excavated by TBM exceeds a threshold, it leads to failure of the soil or rock masses ahead of the tunnel face, which results in heaving the ground surface. In the current research, the upper bound method of limit analysis was employed to calculate the blow-out pressure of tunnels excavated in rock masses obeying the Hoek-Brown nonlinear criterion. The results of the proposed method were compared with three-dimensional finite element models, as well as the available methods in the literature. The results show that when σ_ci, m_i, and GSI increase, the blow-out pressure increases as well. By doubling the tunnel diameter, the blow-out pressure reduces up to 54.6%. Also, by doubling the height of the tunnel cover and the surcharge pressure exerted on the ground surface above the tunnel, the blow-out pressure increased up to 74.9% and 5.4%, respectively. With 35% increase in the unit weight of the rock mass surrounding the tunnel, the blow-out pressure increases in the range of 14.8% to 19.6%. The results of the present study were provided in simple design graphs that can easily be used in practical applications in order to obtain the blow-out pressure.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.560-564
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• 2008

Purpose: Because of traffic accidents and many criminal violences, the incidence of facial trauma has been increasing not only in adults but also in children. We planed this study to introduce our experience about pediatric blow out fracture and provide more information. Methods: We made retrospective study in 76 children with blow out fracture from January 2001 to September 2005 by retrospective chart review including detailed preoperative and postoperative evaluations, age, sex, cause, symptom and sign, and their post-operative complications. Results: Among our patients, 69 were male and 7 were female. The ages ranged from 7 to 18 years, which shows the greatest incidence of blow out fracture. Physical violence(46%) was the most common cause in this group and was followed by vehicle accident(28%), and fall down accident(17%). Left side(64%) showed slightly more incidence than right side(36%), but there were no statistical importance. Ecchymosis(88%) was the most common symptom and followed by periorbital swelling(68%) and diplopia(30%). 30 patients was diagnosed with another facial bone fracture and nasal bone(51%) was the most common associated facial bone fracture. Fourty four Patients(60%) got an orbital wall reconstruction in 7 days after trauma. After the operation, only 3 patients(4%) suffered from diplopia postoperative 3 month, and resolved in 4 years. Conclusion: The incidence of blow out fracture in children has been increasing every year, and violence has become more important etiology of pediatric blow out fracture and public and private education institutions were the most common place that blow out fracture originated. Accurate diagnosis and careful treatment plans are important in pediatric blow out fracture.

• Archives of Craniofacial Surgery
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• v.14 no.1
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• pp.24-29
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• 2013

Background: The incidence of blow out fractures is increasing and the techniques of diagnosis and treatment have been recently evolving. Despite its clinical significance, there has been no study on orbital inferiomedial blow out fractures. Therefore, this study was designed to investigate the clinical significance of treatment of orbital inferiomedial blow out fractures. Methods: A retrospective review of fifty-seven patients who could be followed up for at least 1 year after surgical reconstruction of pure inferiomedial blow out fracture was undertaken. The transconjunctival approach was performed in all cases. The onlay technique was used in 32 patients and the inlay/sheet method was used in 25 patients. We evaluated the clinical outcomes using the chi-square test. Results: In the group using the onlay technique, postoperative diplopia and enophthalmos were observed in 14 cases and 3 cases, respectively. Of these, 5 cases and 3 cases lasted for more than 6 months, respectively. In the group using the inlay/sheet method, postoperative diplopia was observed in 9 cases, but there were no cases of enophthalmos. Among the 9 diplopia cases, 4 lasted for more than 6 months. Conclusion: Postoperative diplopia and enophthalmos were increased after treatment of inferiomedial blow out fractures compared to isolated medial (0.6%, 0.3%) or inferior (1.8%, 0.6%) blow out fractures. Therefore, careful dissection is necessary not to injure the inferior oblique muscle to decrease the incidence of postoperative diplopia. Moreover, the inlay/sheet method is an effective option for reconstruction of inferiomedial blow out fractures.

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.729-734
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• 2007

Purpose: The operative treatment for blow-out fracture involves restoration of intra-orbital soft tissue and bony structural integrity. There are several methods for reconstruction of inferior blow out fracture. We report reduction of inferior blow-out fracture with urinary balloon catheter in comparison with $Medpor^{(R)}$ using group to complication rate. Methods: A retrospective study was performed on 67 patients who underwent inferior orbital blow-out fracture reconstruction with $Medpor^{(R)}$ implant or urinary balloon catheter following between 2003 and 2006. Hospital records were reviewed especially for preoperative and postoperative enophthalmos, diplopia, extraocular muscle movement limitations, and hypoesthesia between $Medpor^{(R)}$ implant group and balloon catheter using group. Results: There was no significant statistical difference between both groups on incidence of postoperative complications of enophthalmos, diplopia, extraocular muscle movement limitations, and hypoesthesia. Postoperative infection, ectropion were absent in both groups.Conclusion: The use of urinary balloon catheter is simple, fast and inexpensive. Urinary balloon catheter is an alternative and reliable use for reduction of inferior orbital blow-out fracture.

• Archives of Craniofacial Surgery
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• v.10 no.1
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• pp.23-28
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• 2009

Purpose: Blow out fracture can present tenderness, swelling, enophthalmos, extraoccular muscle limitation, paresthesia, diplopia according to severity of injury, so reconstruction of blow out fracture is important. Orbital soft tissue should be in orbit and defected orbital wall should be corrected by autologus tissue or alloplastic implants. Every implants have their merits and faults, every implants are used various. This study was designed to compare the sequelae of blow-out fracture repair using the alloplastic implants: micro-titanium mesh(Micro Dynamic titanium $mesh^{(R)}$, Leibinger, Germany), porous polyethylene ($Medpor^{(R)}$, Porex, USA), absorbable mesh plate(Biosorb $FX^{(R)}$ . Bionx Implants Ltd, Finland). Methods: Between January 2006 and April 2008, 52 patients were included in a retrospective study analysing the outcome of corrected inferior orbital wall fracture with various kind of implants. Implants were inserted through subciliary incision. Twenty patients were operated with micro-titanium mesh, fourteen patients with porous polyethylene and eighteen patients with absorbable mesh plate. In comparative category, enophthalmos, diplopia, range of motion of extraoccular muscle, inferior orbital nerve injury were more on frequently statistically in patients. Results: Fourteen of 18 patients underwent surgical repair to improve diplopia, 11 of 17 patients to improve parasthesia, 11 of 15 patients to improve enophthalmos, 8 of 9 patients to improve extraoccular muscle limitation. Duration of follow-up time ranged from 6 months to 12 months(mean, 7.4 months). There was no statistic difference of sequelae between micro titanium mesh and porous polyethylene and absorbable mesh plate in blowout fracture, inferior wall. Conclusion: There is no difference of sequelae between micro-titanium mesh, porous polyethylene and absorbable mesh plate in blow-out fracture, inferior wall. The other factors such as defect size, location, surgeon's technique, may influence the outcome of blow-out fracture repair.

• Journal of Trauma and Injury
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• v.22 no.1
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• pp.44-50
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• 2009

Purpose: The purpose of this study was to evaluate the causes of blow-out fractures, the computed tomography findings, and the associated facial bone fractures in aged patients. Methods: This study was performed by conducting a chart review. From January 2004 to December 2007, the patients who visited the emergency room of Asan Medical Center and were diagnosed as having a blow-out fracture were included in the study population. Patients 60 years of age or older were grouped as the aged group while patients younger than 60 years of age were grouped as the control group. Results: Between the aged group and the control group, there was a difference in the causes of blow-out fractures. The most common cause of blow-out fracture was a slip down in the aged group and violence in the control group (p<0.05). There were no differences in associated symptoms. Extraocular muscle herniation was the only statistically different computed tomography findings. In associated facial bone fractures, the most common fractures were the zygoma in the aged group and the nasal bone in the control group (p<0.05). Conclusion: In patients 60 years of age or older, the most common cause of blow-out fracture was a slip down, and the most common associated facial bone fracture was a zygomatic fracture.

• Journal of Korean Society of Transportation
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• v.32 no.5
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• pp.503-512
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• 2014

In this paper, various tire blow-out force experiment data were collected and analyzed to obtain approximate values of related coefficients such as rolling resistance, self-aligning torque, cornering stiffness, and radial stiffness for the analysis of the motion of vehicles with tire blow-outs. These coefficients related to tire blow-outs were input into a vehicle accident analysis program to simulate and examine the effects of tire blow-outs. Various configurations and velocities of vehicle collisions without tire blow-outs were also used as reference to establish collision events of vehicle collisions with tire blow-outs. For the events, the simulation analysis was performed and collision characteristics were obtained. Consideration of tire blow-outs or damages suggested in this study will greatly contribute to more reliable vehicle accident reconstructions.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.4
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• pp.11-17
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• 2011

In order to see flame behavior in the annular reverse gas turbine combustor, sector combustion test was performed. Ignition test by using torch ignition system was carried out at various combustor inlet velocity and air fuel ratio. Also, flame blow out limit was measured by changing fuel flow rate with constant air mass flow rate. In test results, stable ignition is possible at air excess ratio of 6 and this limit is gradually increased with combustor inlet velocity. The minimum blow out limit is about 4 at 40 m/s of combustor inlet velocity. This blow out limit is also increased up to about 10 with increasing combustor inlet velocity. Test result shows that lean blow out limits are increased with air velocity. The highest blow out limit was found at the combustor inlet velocity of 65 m/s.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.153-159
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• 2010

In order to see the flame behavior in the annular reverse gas turbine combustor, sector combustion test was performed. Ignition test by using torch ignition system was carried out at the various combustor inlet velocity and air fuel ratio. Also, flame blow out limit was measured by changing fuel flow rate with constant air mass flow rate. In the test results, stable ignition is possible at air excess ratio of 6 and this limit is gradually increased with combustor inlet velocity. The minimum blow out limit is about 4 at 40 m/s of combustor inlet velocity. This blow out limit is also increased up to about 10 with increasing combustor inlet velocity. Test result shows that lean blow out limits are increased with air velocity. The highest blow out limit was found at the combustor inlet velocity of 65m/s.