• Journal of Korean Neurosurgical Society
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• v.53 no.6
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• pp.360-363
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• 2013

We recently experienced self-detachment of the Solitaire stent during mechanical thrombectomy of acute ischemic stroke. Then, we tried to remove the detached stent and to recanalize the occlusion, but failed with endovascular means. The following diffusion weighted image MRI revealed no significant increase in infarction size, therefore, we performed surgical removal of the stent to rescue the patient and to elucidate the reason why the self-detachment occurred. Based upon the operative findings, the stent grabbed the main thrombi but inadvertently detached at a severely tortuous, acutely angled, and circumferentially calcified segment of the internal carotid artery. Postoperative angiography demonstrated complete recanalization of the internal carotid artery. The patient's neurological deficits gradually improved, and the modified Rankin scale score was 2 at three months after surgery. In the retrospective case review, bone window images of the baseline computed tomography (CT) scan corresponded to the operative findings. According to this finding, we hypothesized that bone window images of a baseline CT scan can play a role in terms of anticipating difficult stent retrieval before the procedure.

• Communications of Mathematical Education
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• v.19 no.2 s.22
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• pp.327-344
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• 2005

솔리테르(solitaire) 중 간단한 게임인 자리바꾸기 문제에 대해 학습자로 하여금 다양한 해결방법을 산출 하도록 한 후, 그 과정에서 학생들의 수학적 창의성의 발현 과정을 추적해 본다. 제시한 문제 해결 과제에 대한 학습자들의 반응과 해답을 분석함으로써 수학적 창의성에서의 인지적 구성요소인 확산성, 유창성, 논리성, 유연성, 독창성과 정의적 구성요소에 해당하는 적극성, 독자성, 집중성, 정밀성 등이 어떻게 나타나고 있는가를 살펴본다. 또한 그렇게 함으로써 각 구성요소의 의미와 특성을 규명하고자 하며, 나아가 이들 구성요소를 판별할 수 있는 방안에 대한 기초 자료를 제공하고자 한다.

• Journal of Korean Neurosurgical Society
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• v.60 no.6
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• pp.627-634
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• 2017

Objective : Few studies have reported the outcome of mechanical thrombectomy with Solitaire stent retrival (MTSR) in subtypes of acute ischemic stroke. The purpose of this study was to evaluate the efficacy and result of MTSR in acute cardioembolic stroke. Methods : Twenty consecutive patients with acute cardioembolic stroke were treated by MTSR. The angiographic outcome was assessed by thrombolysis in cerebral infarction (TICI) grade. TICI grade 2a, 2b, or 3 with a measurable thrombus that was retrieved was considered as a success when MTSR was performed in the site of primary vessel occlusion, and TICI grade 2b or 3 was considered as a success when final result was reported. Clinical and radiological results were compared between two groups divided on the basis of final results of MTSR. Persistent thrombus compression sign on angiogram was defined as a stenotic, tapered arterial lumen whenever temporary stenting was performed. The clinical outcomes were assessed by the modified Rankin Scale (mRS) at 3 months. Results : The failure rate of MTSR was 20% (4/20) and other modalities, such as permanent stenting, were needed. Final successful recanalization (TICI grade 2b or 3) was 80% when other treatments were included. The rate of good outcome ($mRS{\leq}2$) was 35% at the 3-month follow-up. Failure of MTSR was significantly correlated with persistent thrombus compression sign (p=0.001). Conclusion : Some cases of cardioembolic stroke are resistant to MTSR and may need other treatment modalities. Careful interpretation of angiogram may be helpful to the decision.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.2
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• pp.255-263
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• 2007

Composite resin restorations are widely used to restore decayed teeth or preventive restoration in children. Children often receive topical fluoride treatments on a semiannual basis. However there is concern that topical acidulated phosphate fluorides (APF) may cause deterioration of composite resins. The aim of this study was to evaluate the surface changes in composite resins due to topical fluoride application. Composite resins(Solitaire $2^{(R)}$, Metafil $CX^{(R)}$, Composan $LCM^{(R)}$, $Charmseal^{(R)}$) in topical fluoride agents were immersed and their surface roughness, weight loss and SEM findings were evaluated. The results were as follows: 1. The 4 minutes-immersion group showed more roughened surface than 1 minute-immersion group and the control group showed the smoothest surface among all the materials, and there was statistically significant difference between the groups except the Composan $LCM^{(R)}$ (P<0.05). 2. There was no significant difference between the 1 minute-immersion group and 4 minutes-immersion group in weight loss (P>0.05) 3. The experimental group treated with topical fluoride gel showed generally more roughened surface than control group in the SEM findings.

• Journal of Korean Neurosurgical Society
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• v.65 no.3
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• pp.422-429
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• 2022

Objective : Extracranial supra-aortic dissections (ESADs) with severe stenosis, occlusion and/or pseudoaneurysm presents potential risk of stroke. Endovascular stenting to reconstruct non acute phase ESADs (NAP-ESADs) is an alternative to anticoagulant or antiplatelet therapy. However, its feasibility, safety and efficacy of stenting in NAP-ESADs is unclear. This study aims to investigate the long-term outcomes of the feasibility, safety and efficacy of stenting in NAP-ESADs. Methods : Seventy-four patients with 91 NAP-ESAD vessels with severe stenosis, occlusion and/or pseudoaneurysm presents potential risk of stroke who underwent stent remodeling were enrolled into this respective study from December 2008 to March 2020. Technical success rate, complications, clinical and angiographic results were harvested and analyzed. Results : Success rate of stent deployment was 99% (90/91) with no procedural mortality or morbidity. Transient ischemic attack occurred in three patients during operation (4.1%, 3/74). Asymptomatic embolisms of distal intracranial vessels were found in two patients (2.7%, 2/74). One hundred and forty-two stents deployed at 85 carotid (135 stents) and six vertebral (seven stents) vessels. Six stent types (Wingspan, 28/135, 20.7%; Solitaire, 10/135, 7.4%; Neuroform, 8/135, 5.9%; LVIS, 2/135, 1.5%; Precise, 75/135, 55.6%; Acculink, 12/135, 8.9%) were deployed at carotid arterial dissection while two types (Wingspan, 5/7, 71.4%; Solitaire 2/7, 28.6%) at vertebral arterial dissection. Digital subtracted angiography (56%, 51/91), computational tomography angiography (41.8%, 38/91) and high resolution magnetic resonance imaging (2.2%, 2/91) were adopted for follow up, with a mean time of 17.2±15.4 months (5-77). All patient modified Rankin Scale scores showed no increase at discharge or follow-up. Angiographically, dissections in 86 vessels in 69 patients (94.5%, 86/91) were completely reconstructed with only minor remnant dissections in four vessels in four patients (4.4%, 4/91). Severe re-stenosis in the stented segment required re-stenting in one patient (1.1%, 1/91). Conclusion : Stent remodeling technique provides feasible, safe and efficacious treatment of ESADs patients with severe stenosis, occlusion and/or pseudoaneurysm.

• Korean Journal of Radiology
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• v.23 no.2
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• pp.246-255
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• 2022

Objective: To determine the usefulness of Silent MR angiography (MRA) for evaluating intracranial aneurysms treated with stent-assisted coil embolization. Materials and Methods: Ninety-nine patients (101 aneurysms) treated with stent-assisted coil embolization (Neuroform atlas, 71 cases; Enterprise, 17; LVIS Jr, 9; and Solitaire AB, 4 cases) underwent time-of-flight (TOF) MRA and Silent MRA in the same session using a 3T MRI system within 24 hours of embolization. Two radiologists independently interpreted both MRA images retrospectively and rated the image quality using a 5-point Likert scale. The image quality and diagnostic accuracy of the two modalities in the detection of aneurysm occlusion were further compared based on the stent design and the site of aneurysm. Results: The average image quality scores of the Silent MRA and TOF MRA were 4.38 ± 0.83 and 2.78 ± 1.04, respectively (p < 0.001), with an almost perfect interobserver agreement. Silent MRA had a significantly higher image quality score than TOF MRA at the distal internal carotid artery (n = 57, 4.25 ± 0.91 vs. 3.05 ± 1.16, p < 0.001), middle cerebral artery (n = 21, 4.57 ± 0.75 vs. 2.19 ± 0.68, p < 0.001), anterior cerebral artery (n = 13, 4.54 ± 0.66 vs. 2.46 ± 0.66, p < 0.001), and posterior circulation artery (n = 10, 4.50 ± 0.71 vs. 2.90 ± 0.74, p = 0.013). Silent MRA had superior image quality score to TOF MRA in the stented arteries when using Neuroform atlas (4.66 ± 0.53 vs. 3.21 ± 0.84, p < 0.001), Enterprise (3.29 ± 1.59 vs. 1.59 ± 0.51, p = 0.003), LVIS Jr (4.33 ± 1.89 vs. 1.89 ± 0.78, p = 0.033), and Solitaire AB stents (4.00 ± 2.25 vs. 2.25 ± 0.96, p = 0.356). The interpretation of the status of aneurysm occlusion exhibited significantly higher sensitivity with Silent MRA than with TOF MRA when using the Neuroform Atlas stent (96.4% vs. 14.3%, respectively, p < 0.001) and LVIS Jr stent (100% vs. 20%, respectively, p = 0.046). Conclusion: Silent MRA can be useful to evaluate aneurysms treated with stent-assisted coil embolization, regardless of the aneurysm location and type of stent used.

• English & American cultural studies
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• v.13 no.1
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• pp.1-28
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• 2013

Edward Abbey is regarded as one of the most influential ecological or nature writers. He celebrates the American Southwestern desert, argues for wilderness preservation, and advocates politically-oriented environmental activism to defend wilderness. He, however, does not classify himself as a nature writer, but rather places himself in the tradition of a kind of autography. His books show his fascination with the delicate harmony of the desert, and at the same time his personal journey over the desert. That is, eco-centered, he keeps his journey into the heart of the desert. He finds the desert harsh, brutal, fatal, and most of all, indifferent. The desert reveals simplicity and mystery, silence and revelation, and emptiness and fulfillment. This mythical and paradoxical essence of the desert draws him into the place and inspires redemptive humility and beauty, which, in turn, peel off his old ego or self. During his journey, Abbey tries to immerge himself with the desert yet remains intact and individual. The desert serves for him as the bedrock which sustains him and offers an opportunity to gain a new whole perspective. Like a pocket hunter in the desert whom he characterizes himself, he sticks to the desert to dig out ground for his existence and survival. Pulling the energy and force of the desert into his soul, Abbey is free, or compelled to contemplate what is beyond the human. His experience in and of the desert leads to a discovery of self and initiates selfhood.

• Archives of Plastic Surgery
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• v.51 no.2
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• pp.187-195
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• 2024

Primary tuberculous osteomyelitis involving the mandible represents less than 2% of skeletal locations. In this paper, we report a case of mandibular tuberculosis (TB) detected after histopathological analysis of the surgically resected specimen during surgical management of a suspected case of ameloblastoma. A 14-year-old male patient presented to us with history of right-sided chin swelling. The clinical examination revealed a swelling, involving right body and parasymphysis of mandible, measuring approximately 6 cm in length and 2 cm in width, extending from right lateral incisor till the first molar. Radiological scans revealed a large multiloculated osteolytic expansive lesion measuring 52 × 20 × 18 mm. Excision of the lesion was performed and reconstruction was done with iliac bone grafting. The histopathological findings revealed a granulomatous lesion, suggestive of tuberculous osteomyelitis. The patient was successfully treated with standard multidrug therapy. One year after completion of therapy, there were no signs of recurrence. Primary mandibular TB is an extremely rare entity. Its clinical presentation is not specific. Radiologically, TB has no characteristic appearance. The positive diagnosis is based on histology. Primary mandibular TB is rare and should be kept among differential diagnoses in susceptible population and in endemic areas.

• Journal of Korean Neurosurgical Society
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• v.53 no.2
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• pp.77-82
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• 2013

Objective : Sudden major cerebral artery occlusion often resists recanalization with currently available techniques or can results in massive symptomatic intracranial hemorrhage (sICH) after thrombolytic therapy. The purpose of this study was to examine mechanical recanalization with a retrievable self-expanding stent and balloon in acute intracranial artery occlusions. Methods : Twenty-eight consecutive patients with acute intracranial artery occlusions were treated with a Solitaire retrievable stent. Balloon angioplasty was added if successful recanalization was not achieved after stent retrieval. The angiographic outcome was assessed by Thrombolysis in Cerebral Infarction (TICI) and the clinical outcomes were assessed by the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Results : At baseline, mean age was 69.4 years and mean initial NIHSS score was 12.5. A recanalization to TICI 2 or 3 was achieved in 24 patients (85%) after stent retrieval. Successful recanalization was achieved after additional balloon angioplasty in 4 patients. At 90-day follow-up, 24 patients (85%) had a NIHSS improvement of ${\geq}4$ and 17 patients (60%) had a good outcome (mRS ${\leq}2$). Although there was sICH, there was one death associated with the procedure. Conclusion : Mechanical thromboembolectomy with a retrievable stent followed by additional balloon angioplasty is a safe and effective first-line therapy for acute intracranial artery occlusions especially in case of unsuccessful recanalization after stent thrombectomy.

• Journal of Korean Neurosurgical Society
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• v.60 no.2
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• pp.155-164
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• 2017

Objective : To evaluate the efficacy of balloon guiding catheter (BGC) during thrombectomy in anterior circulation ischemic stroke. Methods : Sixty-two patients with acute anterior circulation ischemic stroke were treated with thrombectomy using a Solitaire stent from 2011 to 2016. Patients were divided into the BGC group (n=24, 39%) and the non-BGC group (n=38, 61%). The number of retrievals, procedure time, thrombolysis in cerebral infarction (TICI) grade, presence of distal emboli, and clinical outcomes at 3 months were evaluated. Results : Successful recanalization was more frequent in BGC than in non-BGC (83% vs. 66%, p=0.13). Distal emboli occurred less in BGC than in non-BGC (23.1% vs. 57.1%, p=0.02). Good clinical outcome was more frequent in BGC than in non-BGC (50% vs. 16%, p=0.03). The multivariate analysis showed that use of BGC was the only independent predictor of good clinical outcome (odds ratio, 5.19 : 95% confidence interval, 1.07-25.11). More patients in BGC were successfully recanalized in internal carotid artery (ICA) occlusion with small retrieval numbers (<3) than those in non-BGC (70% vs. 24%, p=0.005). In successfully recanalized ICA occlusion, distal emboli did not occur in BGC, whereas nine patients had distal emboli in non-BGC (0% vs. 75%, p=0.001) and good clinical outcome was superior in BGC than in non-BGC (55.6% vs. 8.3%, p=0.01). Conclusion : A BGC significantly reduces the number of retrievals and the occurrence of distal emboli, thereby resulting in better clinical outcomes in patients with anterior circulation ischemic stroke, particularly with ICA occlusion.