• Geomechanics and Engineering
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• 제20권2호
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• pp.147-154
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• 2020

A novel approach for predicting lateral displacement caused by pile installation in anisotropic clay is presented, on the basis of the cylindrical and spherical cavities expansion theory. The K₀-based modified Cam-clay (K₀-MCC) model is adopted for the K₀-consolidated clay and the process of pile installation is taken as the cavity expansion problem in undrained condition. The radial displacement of plastic region is obtained by combining the cavity wall boundary and the elastic-plastic (EP) boundary conditions. The predicted equations of lateral displacement during single pile and multi-pile installation are proposed, and the hydraulic fracture problem in the vicinity of the pile tip is investigated. The comparison between the lateral displacement obtained from the presented approach and the measured data from Chai et al. (2005) is carried out and shows a good agreement. It is suggested that the presented approach is a useful tool for the design of soft subsoil improvement resulting from the pile installation.

• 대한치과의사협회지
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• 제56권3호
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• pp.142-150
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• 2018

In the posterior maxillary area, due to resorption of the ridge after extraction and pneumatization of the maxillary sinus, the height of the alveolar ridge may not be sufficient for placement of implants. To solve this problem, sinus augmentation using both crestal and lateral approaches have been widely used. Jung et al. (2010) introduced the modified lateral approach technique, which is a simplified technique that combines the advantages of crestal and lateral approaches. The purpose of this case report is to report two cases in the posterior maxilla in which simultaneous implant placement with maxillary sinus augmentation has been performed using the modified lateral approach technique. In two female patients, 67 and 74 years old, respectively, simultaneous implant placement was performed using the modified lateral approach technique on the left maxillary second premolar and the first molar. In both patients, the residual bone height on the distal side of the maxillary second premolar was measured to be approximately 5 mm, and the residual bone height of the first molar was measured to be 2-3 mm. After flap elevation, osteotomy of the lateral window was performed in the form of a mesiodistally extended slot above the sinus floor and the Schneiderian membrane was elevated. Sequenced drilling was performed while protecting the membrane with a periosteal elevator. Bone graft and implant placement was performed after preparation of the implant site. Sufficient primary stability was achieved for each implant and sinus membrane was not perforated. After four and five months respectively, implant second surgery was performed. Clinically, the implants were observed to be stable. Implants and surrounding peri-implant mucosa were well maintained after prosthodontic treatment. In conclusion, the modified lateral approach could be a predictable and efficient technique for implant placement in the atrophied posterior maxilla.

• The Korean Journal of Pain
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• 제10권2호
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• pp.254-257
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• 1997

Ganglion impar lies immediately anterior to the sacrococcygeal junction and blockade of the ganglion is used to treat anorectal and perineal pain. Although the technique introduced by Plancarte et at is widely practised, the bent needle is sometimes difficult to position precisely and patients find the procedure painful. We modified this approach of block of ganglion impar by positioning the needle into the sacrococcygeal junction and using the loss of resistance technique. With the patient in the lateral position, a skin wheal was raised at 1-1.5cm below the sacral hiatus. Twenty-three gauge short needle was directly placed into the sacrococcygeal junction with aid of fluoroscopic guidance. From 1 cm behind the anterior margin of the vertebral body in lateral view, we used the loss of resistance technique to confirm the retroperitoneal space. We found this modified approach easier to perform during six blocks for three patients with anorectal or perineal pain. Our modified approach through the sacrococcygeal junction may provide opportunity for wider administration of this procedure because of its simple technique, reduced pain during procedure and decreased risk of infection.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.3.1-3.9
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• 2019

Background: The infratemporal fossa (ITF) is an anatomical lateral skull base space composed by the zygoma, temporal, and the greater wing of the sphenoid bone. Due to its difficult approach, surgical intervention at the ITF has remained a heavy burden to surgeons. The aim of this article is to review basic skull base approaches and ITF structures and to avoid severe complications based on the accurate surgical knowledge. Methods: A search of the recent literature using MEDLINE (PubMed), Embase, Cochrane Library, and other online tools was executed using the following keyword combinations: infratemporal fossa, subtemporal fossa, transzygomatic approach, orbitozygomatic approach, transmaxillary approach, facial translocation approach, midface degloving, zygomatico-transmandibular approach, and lateral skull base. Aside from our Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) trial, there have been very few randomized controlled trials. The search data for this review are summarized based on the authors' diverse clinical experiences. Results: We divided our results based on representative skull base approaches and the anatomy of the ITF. Basic approaches to the ITF include endoscopic endonasal, transzygomatic, orbitozygomatic, zygomatico-transmandibular, transmaxillary, facial translocation, and the midfacial degloving approach. The borders and inner structures of the ITF (with basic lateral skull base dissection schemes) are summarized, and the modified zygomatico-transmandibular approach (ZTMA) is described in detail. Conclusions: An anatomical basic knowledge would be required for the appropriate management of the ITF pathology for diverse specialized doctors, including maxillofacial, plastic, and vascular surgeons. The ITF approach, in conjunction with the application of microsurgical techniques and improved perioperative care, has permitted significant advances and successful curative outcomes for patients having malignancy in ITF.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.381-388
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• 2002

A series of centrifuge model tests were performed to investigate the behavior of piled bridge abutment subjected to lateral soil movements induced by the construction of approach embankment. In these tests, both the depth of soft clay and the rate of embankment construction are chosen as key parameters to examine the effects on lateral soil movements. The depth of soft clay layer varies from 5.2 m to 11.6 m, and the rate of embankment construction has two types of staged construction(1m/30days, 1m/15days) and instant construction. It is shown that, the distribution of lateral flow induced by stage embankment construction has a trapezoidal distribution. And practical guidelines to check the possibility of some lateral movement of piled abutment were investigated. The validity of the proposed guidelines by centrifuge test was compared with the observed performance by lateral movement index, F(Japan Highway Public Corporation) and modified I index(Korea Highway Corporation). Based on the results obtained, the critical values of F and modified I, as a practical guidelines, are proposed to 0.03 and 2.0, respectively.

• 대한후두음성언어의학회지
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• 제25권2호
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• pp.90-95
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• 2014

Background and Objectives : Arytenoid adduction procedure is one of the main surgical options addressed for the correction of glottal incompetence in patients with unilateral vocal cord paralysis. Traditionally, a midline approach is used for identifying and suturing around the muscular process, which often needs over-traction of the thyroid cartilage and results in patient's discomfort as well as surgeon's distress. The authors investigated the advantage of a modified procedure, lateral approach, in which the arytenoid cartilage is exposed through the space between strap muscles and sternocleidomastoid muscle. Materials and Methods : Retrospective chart review was performed for 66 patients who received arytenoid adduction surgery at Samsung Medical Center, between the year 1997 and 2014. Operation time, types of anesthesia, voice outcomes and complications were compared between the midline (n=22) and the lateral (n=44) approach group. Results : Operation time was shorter in the lateral approach group ($125{\pm}24min$) than in the midline group ($144{\pm}24min$). Arytenoid adduction was proceeded under local anesthesia in 66% (n=29/44) and 14% (n=3/22) of patients with lateral and midline approach group, respectively. Voice outcomes and complication rates were comparable between the two groups. Injection laryngoplasty in conjunction with arytenoid adduction resulted in more favorable voice outcomes. Conclusion : A lateral approach for the arytenoid adduction procedure showed comparable voice outcomes and similar complication rates with those of a midline approach. However, lateral approach provided less discomfort to the patients and less distress to a surgeon, and therefore, shorter operation time was needed and local anesthesia could be more frequently applied for this modified procedure.

• Journal of Korean Neurosurgical Society
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• 제30권1호
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• pp.114-117
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• 2001

Generally, the posterolateral approach had been recommended in case of extraforaminal disc herniation or lateral stenosis but it has been speculated that this procedure may be feasible to posterolateral disc herniation at the high lumbar levels of the L1-L2 interspace. Topographically, a posterolateral approach should be able to access anteromedial side of the spinal canal without the risk of the bony instability and damage to the neural structures. During the past one year period, three patients with high lumbar discs at the L1-L2 level were treated by the modified posterolateral approach. This article describeds the details of this approach with pertinent literature review.

• Journal of Korean Neurosurgical Society
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• 제51권6호
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• pp.334-337
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• 2012

Objective : The lateral supraorbital (LSO) approach is a modified method of the classic pterional approach and it has advantages of short skin incision and small craniotomy compared with the pterional approach. This study was designed to compare the two approaches in the surgical treatment of unruptured intracranial aneurysms. Methods : We retrospectively reviewed 122 patients with 137 unruptured intracranial aneurysms treated by clipping, from July 2009 to April 2011. Between August 2010 and April 2011, 61 patients were treated by clipping via the lateral supraorbital approach and the same number of patients treated by clipping via the pterional approach were retrospectively enrolled. We analyzed the two groups and compared demographic, radiologic and clinical variables. Results : The mean age of patients in the two groups was 54.6 years (LSO group) and 55.7 years (Pterion group). The mean duration of hospitalization was shorter in the LSO group than in the Pterion group (7.9 days vs. 9.0 days, p=0.125) and the mean operation time was also significantly shorter in the LSO group (117.1 minutes vs. 164.3 minutes, p<0.001). Furthermore, the mean craniotomy area was much smaller in the LSO group (1275.4 $mm^2$ vs. 2858.9 $mm^2$, p<0.001). The two groups showed similar distributions of aneurysm location and postoperative complications. Conclusion : The lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.

• Journal of Korean Neurosurgical Society
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• 제29권12호
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• pp.1677-1681
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• 2000

Microsurgical transthoracic extrapleural approach for thoracic discectomy in three cases were modified and simplified in order to achieve better exposure of ventral extradural space than posterolateral extrapleural(lateral extracavitary) approach and less pulmonary complications than transthoracic transpleural approach. These approaches were optimized by microscope and video-assistance. Surgery was followed by clinical improvement in all patients. The results of treatment seem to support the use of these modified techniques as adequate surgical treatment of thoracic disc herniations without any complications.

• The Korean Journal of Pain
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• 제29권1호
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• pp.57-61
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• 2016

Foraminal or extraforaminal Far Lateral Disc Herniations (FLDH) extending into or beyond the foraminal zone have been recognized as between 7-12% of all lumbosacral disc herniations. Conventional posterior laminectomy may not provide good access to a herniation that lies far lateral to the lateral margin of the pedicle. Use of the endoscopic technique through a percutaneous approach to treat such FLDH patients can decrease the surgical morbidity while achieving better outcomes. We made an effort to utilize the advantages of percutaneous endoscopic lumbar discectomy (PELD) and to determine the appropriate approach for FLDH at the level between the 5th Lumbar and first Sacral vertebrae(L5-S1). The authors present a case of an endoscopically resected lumbar extruded disc of the left extraforaminal zone with superior foraminal migration at the level of L5-S1, which had led to foot drop, while placing the endoscope in the anterior epidural space without facetectomy.