• Journal of KIISE:Software and Applications
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• v.30 no.12
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• pp.1247-1254
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• 2003

Currently. the north american symptomatic carotid endarterectomy trial, european carotid surgery trial, and common carotid method are used to measure the carotid stenosis for determining candidate for carotid endarterectomy using the projection angiography from different modalities such as digital subtraction angiography. rotational angiography, computed tomography angiography and magnetic resonance angiography. A new computerized carotid stenosis measuring system was developed using MR angiography axial image to overcome the drawbacks of conventional carotid stenosis measuring methods, to reduce the variability of inter-observer and intra-observer. The gray-level thresholding is one of the most popular and efficient method for image segmentation. We segmented the carotid artery and lumen from three-dimensional time-of-flight MRA axial image using gray-level thresholding technique. Using the measured intima-media thickness value of common carotid artery for each cases, we separated carotid artery wall from the segmented carotid artery region. After that, the regions of segmented carotid without artery wall were divided into region of blood flow and plaque. The calculation of carotid stenosis degree was performed as the following; carotid stenosis grading is(area measure of plaque/area measure of blood flow region and plaque) * 100%.

• Journal of KIISE:Software and Applications
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• v.30 no.9
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• pp.821-828
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• 2003

The virtual angioscopy was implemented using MR angiography image of carotid artery Inside of the carotid artery is one of the body region not accessible by real optical endoscopy but can be visualized with virtual endoscopy. In order to determine the navigation path, we segmented the common carotid artery and internal carotid artery from the MR angiography image. We used the coordinates as a navigation path for virtual camera that were calculated from medial axis transformation. We used the perspective projection and marching cube algorithm to render the surface from volumetric MRA image data. A stroke occurs when brain cells die because of decreased blood flow to the brain. The carotid artery is the primary blood vessel that supplies the blood flow to the brain. Therefore, the carotid artery stenosis is the primary reason of stroke. The virtual angioscopy is highly recommended as a diagnosis tool with which the specific Place of stenosis can be identified and the degree of stenosis can be measured qualitatively. Also, the virtual angioscopy can be used as an education and training tool for endoscopist and radiologist.

• Journal of Chest Surgery
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• v.32 no.12
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• pp.1087-1092
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• 1999

배경 :경동맥 내막 절제술의 목적은 뇌졸중 예방에 있다. 경동맥 내막 절제술시 경동맥 혈류를 차단하였을 때 뇌허혈 상태를 초래하는지 가 가장 중요한 문제이다. 경동맥 혈류 역류압은 뇌내 측부혈류 상태를 반영하므로 경동맥 혈류 차단시 역류압과 뇌파검사 소견에 딸라 shunt 삽입여부 기준을 알아보려고 하였다 대상 및 방법 : 1996년 2월부터 1999년 3월까지 경동맥 내막 절제술을 시행받은 16명을 대상으로 하였다 남자가 14명있고 여자가 2명이었으며 평균연령은 66.35$\pm$6.53이었다 수술부위 경동맥 협착은 평균 73.8$\pm$12.33%였고 반대측 경동맥 협착은 평균 60.99$\pm$23.03%였다. 수술중 모든 환자에서 뇌파감시를 하였으며 경동맥 혈류압을 측정하여 40 mmHg 이하이거나 수술반대측 경동맥 완전폐색이 있는 경우 shunt를 삽입하였다 결과 : 술후 1례에서 사망이 있었는데 이 환자는 전, 중 뇌내동맥 영역에 큰 뇌경색이 있으며 동측에 심한 경동맥 협착이 있고 의식은 기면 상태여서 바로 응급수술을 하였다 수술시경동맥 혈류 역류압은 35mmHg 여서 shunt를 사용하였다 술후 1일째 의식이 혼수상태로 나빠져 뇌 단층촬영한 결과 뇌경색 부위에 출혈이 발생하여 사망하였다. 수술 직후 모든 환자에서 뇌허혈에 따른 합병증 및 사망은 없었고 1례에서 수술후 1일째 수술부위 반대편에 적은 뇌경색이 발생하였다 평균 21.5$\pm$11.85개우러의 외래 추적 검사에서 뇌졸중 재발이 없었다. 결론 : 뇌졸중이환후 경동맥 내막 절제술은 최소 4-6주 이상 안정화 시킨 다음 수술하는 것이 좋다고 생각된다 경동맥 내막 절제술은 뇌졸중 예방에 효과적인 치료방법이며 경동맥 혈류역류압이 40mmHg 이하일 경우 shunt를 설치하여 수술하는 것이 안전하다고 사료된다.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.815-821
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• 2006

Background: Carotid endarterectomy is an effective treatment modality in patients with severe carotid artery stenosis, but it may result in serious postoperative complications, We analyzed the results of the carotid endarterectomy performed in our institution to reduce the complications related to the card endarterectomy. Material and Method: We analyzed retrospectively the medical records of 74 patients(76 cases) who underwent carotid endarterectomy for carotid artery stenosis by a single surgeon from February 1996 to July 2004. Result: There were 64 men and 10 women. The mean age of the patients was 63.6 years old. Carotid endarterectomy only was performed in 63 cases, carotid endarterectomy with patch angioplasty in 8 cases, and carotid endarterectomy with segmental resection of internal carotid artery and end to end anastomosis in 5 cases. Intra-arterial shunt was used in 29 cases. The mean back pressures of internal carotid arteries checked after clamping common carotid arteries and external carotid arteries were $23.48{\pm}10.04$ mmHg in 25 cases with changes in electroencephalography(group A) and $47.16{\pm}16.04$ mmHg in 51 cases without changes in electroencephalography(group B). There was no statistical difference in the mean back pressure of internal carotid arteries between two groups(p=0.095), but the back pressures of internal carotid arteries of all patients with changes in electroencephalography were under 40 mmHg. When there was no ischemic change of electroencephalography after clamping common carotid artery and external carotid artery, we did not make use of intra-arterial shunt regardless of the back pressure of internal carotid artery. Operative complications were transient hypoglossal nerve palsy in four cases, cerebral hemorrhage occurred at previous cerebral infarction site in two cases, mild cerebral infarction in one case, hematoma due to anastomosis site bleeding in one case, and upper airway obstruction due to laryngeal edema probably caused by excessive retraction during operation in two cases. One patient expired due to cerebral hemorrhage occurring at previous cerebral infarction site. Conclusion: Carotid endarterectomy is a safe operative procedure showing low operative mortality. We suggest that intra-arterial shunt usage should be decided according to the ischemic change of electroercephalography regardless of the back pressure of internal carotid artery. Excessive retraction during operation should be avoided to prevent upper alway obstruction due to laryngeal edema and if upper airway obstruction is suspected, prompt management is essential.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.399-405
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• 2007

This study examined 202 patients who was diagnosed as arteriosclerosis obliterans around carotid artery caused by its increase in IMT and who have been tested by carotid artery sonography. The results are as follows : 1. Out of 202 research subjects, 120(59.4%) were male, 82(40.6%) female, and the average age was 58. 2. Among the subjects, 54(26.7%) were diagnosed as DM, 60(29.7%) with hyperlipidemia, 86(42.6%) with hypertension, 61(30.2%) with EGK. 3. There was more increase in the left IMT than in the right IMT, more increase in male subjects than female subjects, and more increase with age. 4. The relationship between IMT & MRA was that subjects tested by MRA showed greater statistically significant correlation than those not tested by MRA(p < 0.01). 5. The increase in IMT was correlated with DM and HTN, but not with EKG and hyperlipidemia. 6. Among subjects tested by MRA, those diagnosed with MCA stenosis showed increase upto 0.94 in the left IMT and 0.96 in the right IMT ; there was a significant correlation(p < 0.01). Thicker IMT was positively correlated with diagnosis of MCA stenosis after MRA test.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.88-91
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• 2004

Aortic regurgitation is not a rare complication of Takayasu's disease. Aortic regurgitation may aggravate cerebral ischemic syndrome like syncope in patients with stenotic or occlusive lesions in cerebral branches of aorta secondary to acute or progressive inflammation. In a 34-yrs-old male patient who complained of syncope and exertional dyspnea with occlusion of both carotid arteries and severe stenoses of both subclavian arteries, occlusion of right coronary artery, and aortic regurgitation, his symptom was improved with perioperative aggressive steroid therapy, stent insertion in both subclavian arteries, and aortic valve replacement.

• Journal of radiological science and technology
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• v.32 no.2
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• pp.161-168
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• 2009

The carotid intima-media thickness (IMT) is an early structural marker of the atherosclerotic process and is the only non-invasive test that is currently recommended by the American Heart Association for evaluation of the risk. However, use of this parameter has a limitation because it assumes uniform thickness throughout the blood vessel, whereas atherosclerosis is a focal phenomenon that is confined to intima. In fact, plaque can be found along the atherosclerotic blood vessels even though its value is unknown. The aim of this study is to analyze the carotid plaque and IMT in the stroke patients. We investigated the patients with ischemic stroke, who were admitted to the department of neurology at the Stroke Special Hospital from January to March 2008. After the carotid IMT and plaque were assessed by B-mode ultrasonography, IMT and carotid plaque to risk variables (age, sex) were analyzed. The distribution of CCA IMT was significantly different in terms of age (p = 0.004). Likewise, the distribution of carotid plaque was also significantly different in terms of age (p = 0.006). Carotid plaque was 69 and 92% in normal and abnormal CCA IMTs respectively. The results showed that the CCA IMT was closely associated with carotid plaque.

• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.178-183
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• 2022

Polycythemia vera (PV) is a rare myeloproliferative disease that causes elevated absolute red blood cell (RBC) mass due to uncontrolled RBC production. Moreover, this condition has been associated with a high risk of ischemic stroke and large vessel stenosis or occlusion, with many studies reporting cerebral infarction in PV patients. Despite these findings, there have been no reports on the vessel wall MRI (VW-MRI) findings of the narrowed vessels in PV-associated ischemic stroke patients. To the best of our knowledge, this is the first report in English regarding the carotid VW-MRI findings of a 30-year-old male diagnosed with PV after being hospitalized due to stroke.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.115-120
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• 2011

Purpose: To examine the feasibility of the treatment planning for minimizing carotid artery dose in the radiotherapy of early glottic cancer. Materials and Methods: From 2007 to 2010, computed tomography simulation images of 31 patients treated by radiotherapy for early glottic cancer were analyzed. The virtual planning was used to compare the parallel-opposing fields (POF) with the modified oblique fields (MOF) placed at angles to exclude the ipsilateral carotid arteries. Planning target volume (PTV), irradiated volume, carotid artery, and spinal cord were analyzed at a mean dose, $V_{35}$, $V_{40}$, $V_{50}$ and with a percent dose-volume. Results: The beam angles were arranged 25 degrees anteriorly in 23 patients and 30 degrees anteriorly in 8 dose-volume of carotid artery shows the significant difference (p<0.001). The mean doses of carotid artery were 38.5 Gy for POF and 26.3 Gy for MOF and the difference was statistically significant (p=0.012). Similarly, $V_{35}$, $V_{40}$, and $V_{50}$ also showed significant differences between POF and MOF. Conclusion: The modified oblique field was respected to prevent a carotid artery stenosis and reduce the incidence of a stroke based on these results.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.363-372
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• 1997

One hundred forty-four patients underwent operation for coarctation of the aorta at Seoul National University Children's Hospital between June 1986 and Decembsr 1995. Age ranged 0.1 to 191 months. Of these 78.5%(113) were infants. We classified the patients in terms of the anatomic location of coarctatiln and the associatCd anomalies(I[401= primary coarctation, 11(741=isthmic hypoplasia, lIIf30)=tubular hypoplasia involving transverse arch, Ar63 =with ventricular septal defect, B(28)=with other major cardiac defects). Subcalvian flap coarctoplasty(60), resection & anastomosis(44), extended aortoplasty(26), and onlay patch(14) were used as surgical methods. Overall operative mortality was 16.0(23/144)%. The hospital mortality was signific'antly higher in patheints with type 111, subtype B, younger age(under 3 months), extended aortoplasty(p(0.01). However, one-stage total repair in patients with subtype A or B were not found to be a predictor of hospital death. Restenosis had occured in 18 patients among 121 survivals(14. 9%). The mean follow-up period was 29.1 $\pm$28.8(0~129.2) months. Preoperative, immediate postoperative(within 3 months after operation) and postoperative(later than 6 months after operation) echocardiographic data on the dimensions of ascending aorta(AA), transverse arch(TA), an4 aortic isthmus(Al) were available in 77 patients(I=20, ll=42, 111= 15). Preoperative and postoperative aortic isthmus(All) and tra sverse arch indices(TAI), defined as TAIAA & AIIAA respectively, were compared. Immediate postoperative All in type 1, II and TAI in type 111 were significantly smaller in stenotic than non-stenotic group suggesting incomplete relieves of stenotic segment Younger age, subclavian coarctoplasty in patient under 3 months of age were round to be the risk factors for restenosis in this series. In conclusion, We found that aortic arch index and transverse arch index can be a useful tool to figure out the anatomic and clinical characteristics of the patients with aortic coarctation, and that anatomy, associated anomalies, age, and surgical methods may influence the surgical outcome of the coarctation repair.