• Journal of Chest Surgery
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• v.33 no.8
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• pp.676-680
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• 2000

To minimize the period of brain ischemia and the potential for neurologic damage during aortic arch replacement, we used the arch-first technique. First case was a 28-year-old female with extensive aneurysm involving ascending, arch and descending thoracic aorta. Exposure was obtained via a bilateral via a bilateral thoracotomy (clamshell incision) in the anterior 4th right and 3rd left intercostal space with oblique sternotomy. To prepare for arch perfusion, the side-arm graft(10mm) was anastomosed to the aortic graft, opposite the site of the planned anastomosis to the arch vessels. After completing the arch anastomosis under total circulatory arrest(37min) and retrograde cerebral perfusion(12min), aortic graft was clamped on either side and the arch was perfused via side-arm graft for 36min. When distal aortic anastomosis was finished, distal clamp of aortic graft was released and arch vessels were perfused via common femoral artery, and the proximal aortic anastomosis was accomplished. The patient was discharged with no event. Second case was a 48-year-old male with extensive aneurysm involving ascending, arch, and aortic regurgitaiton(grade III/IV). This case was also done using the clamshell incision. Aortic valve replacement was done by valved-conduit(Vascutek 30mm), both coronary artery anastomosis using Cabrol's procedure. Last operation procedure was the same as the 1st case.

• Journal of Chest Surgery
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• v.57 no.1
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• pp.99-102
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• 2024

This article presents a straightforward hybrid arch technique for treating residual type B aortic dissecting aneurysms following type A repair (replacement of the ascending aorta) that employs a frozen elephant trunk (FET) straight vascular prosthesis. The debranch-first method involves only cutting and sewing the previous ascending graft, inserting the FET from zone 0, and debranching the arch vessels using a trifurcated graft. This technique is less invasive as it eliminates the need to manipulate the dissected distal arch aneurysm. We successfully applied this technique to 3 patients, with no instances of in-hospital death, stroke, or paraplegia. The debranch-first technique, combined with zone-0 FET insertion, simplifies the redo repair of residual type B aortic dissection.

• Journal of Chest Surgery
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• v.37 no.11
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• pp.903-910
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• 2004

Background: The total aortic arch replacement is one of the most difficult operations with high mortality rate. But the arch first technique with subclavian arterial perfusion has been reported to be a safe methods for arch replacement. Material and Method: Between Feb 2003 and July 2004, 18 patients, 10 men and 8 women, underwent total aortic arch replacement with arch first technique. Their mean age was $59.3\pm12.9$ years. The patietns received 11 acute aortic dissections, 3 chronic aortic dissectiong aneurysms, and 4 ruptured aortic arch aneurysms. Result The mean admission period was $20.2\pm7.4$ days. There was one early mortality case which died of low cardiac output syndrome and another late mortality case which died of cerebral hemorrhage. The others were discharged without any sequelae and they were followed up for an average period of $180\pm156.3$ days. Conclusion: The total aortic arch replacement with arch first technique and subclavian arterial perfusion is a good method that will reduce the surgical mortality and the possibility of secondary late reoperation from the remnant distal aortic problems.

• Structural Engineering and Mechanics
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• v.39 no.6
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• pp.751-765
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• 2011

The present paper deals with the identification of a concentrated damage in an elastic parabolic arch through the minimization of an objective function which measures the differences between numerical and experimental values of static displacements. The damage consists in a notch that reduces the height of the cross section at a given abscissa and therefore causes a variation in the flexural stiffness of the structure. The analytical values of static displacements due to applied loads are calculated by means of the principle of virtual work for both the undamaged and damaged arch. First, pseudo-experimental data are used to study the inverse problem and investigate whether a unique solution can occur or not. Various damage intensities are considered to assess the reliability of the identification procedure. Then, the identification procedure is applied to an experimental case, where displacements are measured on a prototype arch. The identified values of damage parameters, i.e., location and intensity, are compared to those obtained by means of a dynamic identification technique performed on the same structure.

• The Journal of Advanced Prosthodontics
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• v.10 no.4
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• pp.265-270
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• 2018

PURPOSE. The purpose of this in vitro study was to evaluate the accuracy of a new implant impression technique using bite impression coping and a dual arch tray. MATERIALS AND METHODS. Two implant fixtures were placed on maxillary left second premolar and first molar area in dentoform model. The model with two fixtures was used as the reference. The impression was divided into 2 groups, n=10 each. In group 1, heavy/light body silicone impression was made with pick up impression copings and open tray. In group 2, putty/light body silicone impression was made with bite impression copings and dual arch tray. The reference model and the master casts with implant scan bodies were scanned by a laboratory scanner. Surface tessellation language (STL) datasets from test groups was superimposed with STL dataset of reference model using inspection software. The three-dimensional deviation between the reference model and impression models was calculated and illustrated as a color-map. Data was analyzed by independent samples T-test of variance at ${\alpha}=.05$. RESULTS. The mean 3D implant deviations of pick up impression group (group 1) and dual arch impression group (group 2) were 0.029 mm and 0.034 mm, respectively. The difference in 3D deviations between groups 1 and 2 was not statistically significant (P=.075). CONCLUSION. Within limitations of this study, the accuracy of implant impression using a bite impression coping and dual arch tray is comparable to that of conventional pick-up impression.

• Journal of architectural history
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• v.23 no.1
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• pp.7-19
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• 2014

This study considers the proper repair techniques by examining the most representative repair cases of the Korean arch bridges and proposes the constructional manual which can apply similar occasions. The cases are Seonamsa Seungseongyo and Songgwangsa Geukrockgyo where this researcher had taken part in the repair works. This Study proposes the maintenance construction manual about the performance degradation drew by performance degradation of the both Korean arch bridges in the maintenance process. First, arch bridge maintenance should be carried out in the dry season, when water is impermeable in the bottom surface of the bridge. Moreover, risk factors of the maintenance should be excluded to secure the water vally flow, the bypass and the temporary bridge. Second, prior to repair, it has to precede (1)3D shooting (2)formal examination (3)structure safety test (4)geological and lithic surveys (5)arch curvature establishment and makeshift frame settlement before transformation (6)relationship expert comments. Third, if the baduk and the foundation stones are inevitable to replace due to performance degradation on the foundation, it should use the high quality stones and secure greater stress by extending the standard range. The foundation on irregular rock needs to be flattened and underside on the replaced materials require Grengyijil to deliver the equal loads. Fourth, In the process of dismantling the stones of the arched bridge, it could make heavy weathering degree and not reuse the materials. Charge should converge the expert advices to choose the reuseable, the conservate and the alternative materials, and increase the reutilization of the raw materials by preservation and reinforcement treatments. Fifth, the side wall should be repaired by the rubble work technique which is not able to pile compost satiety, so it must use long depth of masonary stones for reinforcement. It is considered to reinforce the stone wall in shore as much as possible and protect the abutment and the side wall on the upstream for the arch bridge maintenance works.

• Structural Engineering and Mechanics
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• v.47 no.1
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• pp.59-73
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• 2013

The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs's rule of shear stress distribution, the box girder's longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge's box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.1
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• pp.69-77
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• 1984

In this paper, the governing differential equations for the free vibration of uniform parabolic arches are derived on the basis of equilibrium equations of a small element of arch rib and the D'Alembert principle. A trial eigen value method is used for determining the natural frequencies and mode shapes. And the Runge-Kutta fourth order integration technique is also used in this method to perform the integration of the differential equations. A detailed study is made of the first mode for the symmetrical and anti-symmetrical vibrations of hinged arches with the Span length equal to 10 m. The effects of the rise of arch, the radius of gyration and the rotary inertia on free vibrations are presented in detail in curves and table.

• Journal of Chest Surgery
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• v.49 no.1
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• pp.54-58
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• 2016

A 49-year-old male presented with chills and a fever. Five years previously, he underwent ascending aorta and aortic arch replacement using the elephant trunk technique for DeBakey type 1 aortic dissection. The preoperative evaluation found an esophago-paraprosthetic fistula between the prosthetic graft and the esophagus. Multiple-stage surgery was performed with appropriate antibiotic and antifungal management. First, we performed esophageal exclusion and drainage of the perigraft abscess. Second, we removed the previous graft, debrided the abscess, and performed an in situ re-replacement of the ascending aorta, aortic arch, and proximal descending thoracic aorta, with separate replacement of the innominate artery, left common carotid artery, and extra-anatomical bypass of the left subclavian artery. Finally, staged esophageal reconstruction was performed via transthoracic anastomosis. The patient's postoperative course was unremarkable and the patient has done well without dietary problems or recurrent infections over one and a half years of follow-up.

• The Journal of the Korean dental association
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• v.55 no.4
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• pp.296-302
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• 2017

The traditional orthognathic surgery treatment consists of three steps: preoperative orthodontic treatment, orthognathic surgery, and postoperative orthodontic treatment, and the average treatment period is usually two years. Also, patients with Class III malocclusion should spend more time getting their facial features worse during the decompensation process. However, most of the patients who want orthognathic surgery visit the chief complaints of appearance improvement, and resolve this address as soon as possible. The concept of $^{\circ}{\AE}$Surgery - First 'does not cause a facial imbalance caused by decompensation for the pre - operative correction period, and the patient can obtain an improved facial profile immediately after the operation. In addition, the correction period is shortened by Regional Acceleratory Phenomenon (RAP) after surgery. However, it is not applicable to all patients. Patients with severe crowding, severe curve of spee or reverse curve of spee, severe transverse discrepancy of the maxilla and mandibular arch, and severe incisal angles are less likely to apply the technique. Although it is not yet possible to apply this technique to all patients, it has many advantages over the conventional method. Especially, the patients' preference is increasing due to the rapid appearance improvement and the shortening of the total treatment period.