• ETRI Journal
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• v.30 no.4
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• pp.606-608
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• 2008

MPEG Surround has a potential clipping problem since its encoding is based on downmixing a multichannel signal. We propose a clipping prevention scheme for MPEG Surround, which is composed of modification and recovery processes of a downmix signal with recovery information conveyed in arbitrary downmix gains of an MPEG Surround bitstream. Experiments show that the proposed scheme effectively prevents sound quality degradation caused by clipping problems with negligible additional bit rates.

• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.805-812
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• 2001

Objectives : The goal of the surgical management of large and giant aneurysm is complete extirpation of the aneurysms with preservation or reconstruction of the parent artery. To improve the surgical management results of those aneurysms in the future, we review our experience and discuss technical maneuvers and strategies used to avoid potential complications of those aneurysm surgery. Material and Methods : During the past 12 years, thirty six cases of large and giant aneurysms(diameter>19mm) were managed by surgery. The clinical characteristics, treatment methods, surgical complications and outcome of those cases were analyzed and, based on the review of the literatures, the preventive methods of surgical complication related to the clipping of those aneurysms were discussed. Results : The locations of those aneurysms were anterior circulation in 34 cases and posterior circulation in 2 cases. The most frequent site of aneurysmal location was a paraclinoidal region of the anterior circulation. The aneurysms were managed surgically by direct clipping of aneurysmal neck in 31 cases, aneurysmal trapping followed by extracranial-intracranial bypass in 2 cases, proximal clipping of parent artery, aneurysmorrhaphy, and excision of aneurysm followed by end to end anastomosis of parent artery in each one case. Surgical complications occurred in 13 cases. A parent vessel occlusion by thrombus formation and parent vessel stenosis after clipping of aneurysm were the main complications. We obtained good outcome in 27, fair 5, poor 1 and dead in 3 case(s). Conclusion : We conclude that selection of suitable management method for each case, high quality of surgical technique and prevention of complication during operation are important key points for the successful treatment of large and giant aneurysm. The heparinization prior to application of temporary clip on parent vessels, aneurysmal decompression during dissection and clipping of aneurysm, complete closing of the aneurysmal neck and avoiding the narrowing of parent vessel after clipping of aneurysm were the main technical maneuvers used to avoid complications of those aneurysm surgery.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup1
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• pp.73-78
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• 2001

Objective : Intraoperative rupture of an intracranial aneurysm can interrupt a microsurgical procedure and jeopardize the patient's chance to favorable outcome. The purpose of this study was to analyse and evaluate intraoperative aneurysmal rupture and render ideal prevention and management to intraoperative rupture. Patients and Methods : The authors retrospectively analysed the results of 609 patients who underwent cerebral aneurysm surgery from January 1991 to December 2000. Results : 1) Intraoperative aneurysmal rupture occurred in 73 of 609 consecutive aneurysm surgery, so the incidence was about 12.0% and it was relatively lower than other reports. 2) Aneurysms arising from anterior communicating artery appeared more prone to intraoperative rupture. 3) The size of aneurysm and timing of operation didn't influence intraoperative aneurysmal rupture and temporary clipping didn't reduce the incidence of intraoperative aneurysmal rupture. 4) Intraoperative aneurysmal rupture occured during three specific periods : (1) dissection stage in 61%, (2) clip application stage in 29 %, (3) predissection stage in 10%. 5) In the patients with intraoperative aneurysmal rupture, surgical outcome was relatively good and there was no significant difference in outcome compared with unruptured group. Conclusion : Our suggestion for prevention methods of intraoperative aneurysmal rupture are as follows : 1) minimal brain retraction, 2) sharp and careful aneurysmal neck dissection, 3) gentle clipping with proper clip selection etc. Management methods after intraoperative aneurysmal rupture are as follows : 1) strong aspiration of bleeding point, 2) rapid application of temporary and/or tentative clip, 3) following rapid dissection of neck and proper clip application, 4) use of encircling clip etc.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.2
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• pp.54-63
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• 2010

The intensive rainfall over 455 mm occurred between on 9 to 14 July 2009 triggered debris flows around the mountain area in Jecheon County. We mapped the debris flow area and estimated the debris flow volume using a high resolution digital elevation model (DEM) generated respectively from terrestrial LiDAR (Light Detection And Ranging) and topographic maps. For the LiDAR measurement, the terrestrial laser scanning system RIEGL LMS-Z390i which is equipped with GPS system and high-resolution digital camera were used. After the clipping and filtering, the point data generated by LiDAR scanning were overlapped with digital map and produced DEM after debris flow. The comparison between digital map and LiDAR scanning result showed the erosion and deposition volumes of about $17,586m^3$ and $7,520m^3$, respectively. The LiDAR data allowed comprehensive investigation of the morphological features present along the sliding surface and in the deposit areas.

• Journal of Korean Neurosurgical Society
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• v.40 no.2
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• pp.99-102
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• 2006

Objective : To document surgical mortality and morbidity for the treatment of unruptured intracranial aneurysms, and to identify optimal treatment modalities, the authors reviewed and analyzed the surgical results. Methods : The authors reviewed 49 cases of unruptured intracranial aneurysm without a previous history of subarachnoid hemorrhage from March 1984 through December 2003. Unruptured intracranial aneurysms were categorized as asymptomatic and symptomatic, and operative results were assessed using the Karnofsky scale at 3 months postoperatively. Outcomes were defined as 'excellent' for a Karnofsky scale score of 100, 'good' for a score of $80{\sim}90$, 'fair' for $50{\sim}70$, 'poor' for $10{\sim}40$, or as 'death'. Excellent and good results were defined as a 'favorable' outcome and others as 'unfavorable' outcome. Results : Of the 49 study subjects, 45 had a favorable outcome and 4 an unfavorable outcome. Surgical mortality was 6.1% and surgical morbidity was 2.0% for all subjects. And the symptomatic group had more complications. Conclusion : There were no significant relationships between aneurysmal size, location, and preoperative symptoms with surgical results. And we believe that the reasons for morbidity and mortality are attributable to strokes, thus more attention should be paid to peri- and post-operative patients care with a focus on strokes prevention in the symptomatic group.

• Journal of Korean Neurosurgical Society
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• v.48 no.3
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• pp.199-206
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• 2010

Objective : Paraclinoid segment internal carotid artery (ICA) aneurysms have historically been a technical challenge for neurovascular surgeons. The development of microsurgical approach, advances in surgical techniques, and endovascular procedures have improved the outcome for paraclinoid aneurysms. However, many authors have reported high complication rates from microsurgical treatments. Therefore, the present study reviews the microsurgical complications of the extradural anterior clinoidectomy for treating paraclinoid aneurysms and investigates the prevention and management of observed complications. Methods : Between January 2004 and April 2008, 22 patients with 24 paraclinoid aneurysms underwent microsurgical direct clipping by a cerebrovascular team at a regional neurosurgical center. Microsurgery was performed via an ipsilateral pterional approach with extradural anterior clinoidectomy. We retrospectively reviewed patients' medical charts, office records, radiographic studies, and operative records. Results : In our series, the clinical outcomes after an ipsilateral pterional approach with extradural anterior clinoidectomy for paraclinoid aneurysms were excellent or good (Glasgows Outcome Scale : GOS 5 or 4) in 87.5% of cases. The microsurgical complications related directly to the extradural anterior clinoidectomy included transient cranial nerve palsy (6), cerebrospinal fluid leak (1), worsened change in vision (1), unplanned ICA occlusion (1), and epidural hematoma (1). Only one of the complications resulted in permanent morbidity (4.2%), and none resulted in death. Conclusion : Although surgical complications are still reported to occur more frequently for the treatment of paraclinoid aneurysms, the permanent morbidity and mortality resulting from a extradural anterior clinoidectomy in our series were lower than previously reported. Precise anatomical knowledge combined with several microsurgical tactics can help to achieve good outcomes with minimal complications.

• Journal of Korean Neurosurgical Society
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• v.48 no.6
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• pp.480-484
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• 2010

Objective : To evaluate the role of lumbar drainage in the prevention of shunt-dependent hydrocephalus after treatment of ruptured intracranial aneurysms by coil embolization in good-grade patients. Methods : One-hundred-thirty consecutive patients with aneurysmal subarachnoid hemorrhage in good-grade patients (Hunt & Hess grades I-III), who were treated by coil embolization between August 2004 and April 2010 were retrospectively evaluated. Poor-grade patients (Hunt & Hess grades IV and V), a history of head trauma preceding the development of headache, negative angiograms, primary subarachnoid hemorrhage (SAH), and loss to follow-up were excluded from the study. We assessed the effects on lumbar drainage on the risk of shunt-dependent hydrocephalus related to coil embolization in patients with ruptured intracranial aneurysms. Results : One-hundred-twenty-six patients (96.9%) did not develop shunt-dependent hydrocephalus. The 2 patients (1.5%) who developed acute hydrocephalus treated with temporary external ventricular drainage did not require permanent shunt diversion. Overall, 4 patients (3.1%) required permanent shunt diversion; acute hydrocephalus developed in 2 patients (50%). There was no morbidity or mortality amongst the patients who underwent a permanent shunt procedure. Conclusion : Coil embolization of ruptured intracranial aneurysms may be associated with a lower risk for developing shunt-dependent hydrocephalus, possibly by active management of lumbar drainage, which may reflect less damage for cisternal anatomy than surgical clipping. Coil embolization might have an effect the long-term outcome and decision-making for ruptured intracranial aneurysms.

• The Journal of the Society of Stroke on Korean Medicine
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• v.12 no.1
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• pp.1-7
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• 2011

Objectives : The purpose is to discuss the clinical applications of Orungsan(Goreisan: 五苓散) as an alternative management for increased intracranial pressure in the field of neurosurgery in Japan. Methods and Results : Attention has focused on Kampo medicine(traditional Japanese medicine) for some cerebral disease including chronic subdural hematoma(CSDH) and cerebral infarction in Japan. Orungsan and one of its classes, Sirungtang(Saireto: 柴苓湯) are well known their effects on brain edema. After some studies of Orungsan has the anti-edemic effects by the inhibition of aquaporin, this herbal medicine has been used widely in the neurosurgery field in Japan. It is high time to think about where we are and we go ahead for the progress and the integration in medicine. We have reviewed the studies using Orungsan or Sirungtang, that was reported at the 20th annual meeting of 'the Japan society for Kampo medicine and neurological surgery' was held on November 5, 2011 in Tokyo. Fifteen studies related with Orungsan or Sirungtang were reported among all 32 studies at the meeting. Orungsan in ten, and Sirungtang in five among 14 studies contained specific clinical case. In the aspects of disease, thirteen papers were related with SDH, including CSDH(11), SSDH(1), aneurism clipping for SDH prevention(1), and one was acute cerebral infarction and one was multiple metastatic brain tumor. In the report style, case control study was 7(mostly retrospective), and the case report was 8. Conclusions : Orungsan may be plausible to be an alternative method to reduce brain edema after SDH and other brain injury in the field of neurosurgery.

• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1555-1562
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• 2000

Objects : Surgical management of the distal anterior cerebral artery(DACA) aneurysms presents several unique problems to surgeons, such as difficulty in early identification of parent arteries, high incidence of rebleeding and premature rupture, and requirement of unfamiliar approach other than conventional frontotemporal craniotomy. Therefore, preoperative anatomical knowledge of anterior interhemispheric fissure and entry point of dissection is prerequisite. Authors utilized a frontobasal approach for DACA aneurysms by using consistent external landmark for guidance to the deep structure. Materials and Methods : From Nov. 1995 to Jun. 1999, a surgical clipping of DACA aneurysms was carried out in 9 patients among a total 131 patients with intracranial aneurysms. In each case, the clinical and aneurysmal features were carefully reviewed through the angiograms, medical records, and intraoperative findings. Results : The incidence of DACA aneurysms was 6.9% from our series. All cases were arisen from juxtacallosal por-tion ; 6 cases from pericallosal-callosomarginal(PC-CM) junction and 3 from pericallosal-frontopolar(PC-FP) junction. Associated vascular anomalies were noted in 3 cases and multiple aneurysms in 3 cases, respectively. The preoperative clinical grades were generally poor. An early surgery was performed in 7 cases and frontobasal interhemispheric approaches in 7 cases. Postoperatively, two patients died of complications ; one delayed ischemic vasospasm and one aspiration pneumonia but remaining patients recovered well. Conclusion : The frontobasal interhemispheric approach was useful for DACA aneurysms in early surgery. Division of superior sagittal sinus(SSS) enabled a minimal retraction of brain on both sides, and prevention of intraoperative rupture was possible. Authors suggest the frontopolar(first frontal bridging) vein as a constant external landmark for approaching the genu of the corpus callosum and juxtacallosal DACA aneurysms.