• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2010년 춘계학술대회논문집
• /
• pp.224-227
• /
• 2010

In the present study, the characteristics of blood flow inside a carotid artery numerically investigated with shear rate specific blood viscosity. To simulate the blood flow with a patient-specific arterial geometry, the geometry of a carotid artery was constructed from 2D rain MRA data. The measured data of blood flow velocity at the common carotid artery were used as boundary conditions of the simulation. For the blood rheology data to be used in the simulation, the patient specific blood viscosity over the whole ranges of shear rate was obtained using $BioVisco^{TM}$. From the numerical results of the blood flow in the carotid artery, the increase of blood viscosity and the decrease of wall shear stress could be found in the carotid bifurcated region, more specifically at the post-plaque dilated region. These characteristics of blood viscosity and wall shear stress can be used more precisely and efficiently to predict the region vulnerable to plaque growht or thrombosis on top of the plaque.

• 한국정보과학회논문지:소프트웨어및응용
• /
• 제30권12호
• /
• pp.1247-1254
• /
• 2003

현재 경동맥 내막절제술 시행을 위한 경동맥 협착증의 정도 측정에는 디지털감산조영술(DSA), 회전조영술(rotational angiography), 컴퓨터단층조영술(CTA) 및 자기공명조영술(MRA)로부터 얻어진 경동맥의 투영 영상을 이용하여 북미, 유럽 표준 및 총경동맥 방법이 사용되고 있다. 본 논문에서는 기존의 기계적인 측경기를 이용하는 전형적인 경동맥 협착 측정 방법의 단점을 극복하고, 측정자간의 변화율을 최소화하기 위해 자기공명조영술의 단면 영상을 사용하고 컴퓨터화한 새로운 협착증 정도 측정 방법을 개발하였다. 영상 분할에 사용되는 방법중 가장 널리 사용되고 효율적인 명암값 임계치 방법을 사용하여 경동맥 및 동맥의 내강을 분할하였다. 또한, 각 증례의 측정된 총경동맥의 혈관두께를 사용하여 분할된 경동맥으로부터 혈관을 제거 하였고, 혈관이 제거된 경동맥을 혈류 영역과 플라그 영역으로 분할하였다. 각 단면 영상에서의 경동맥 협착증 정도 측정은 (분할된 플라그 영역/혈류영역 및 플라그를 합한 면적) * 100% 식으로 계산된다.

• Journal of Korean Neurosurgical Society
• /
• 제57권2호
• /
• pp.94-99
• /
• 2015

Objective : The purpose of our study was to assess prevalence of carotid intraplaque hemorrhage (IPH) and associations between territorial acute infarction and IPH on magnetization-prepared rapid acquisition with gradient-echo (MPRAGE) in patients with acute neurologic symptoms. Methods : 83 patients with suspected acute neurologic symptoms were evaluated with both brain diffusion weighted imaging (DWI) and carotid MPRAGE sequences. Carotid plaque with high signal intensity on MPRAGE of >200% that of adjacent muscle was categorized as IPH. We analyzed the prevalence of IPH and its correlation with territorial acute infarction. Results : Of 166 arteries, 39 had a carotid artery plaque. Of these arteries, 26 had carotid artery stenosis less than 50%. In all carotid arteries, MR-depicted IPH was found in 7.2% (12/166). High-signal intensity on DWI was found in 17.5% (29/166). Combined lesion with ipsilateral high-signal intensity on DWI and IPH on carotid MPRAGE sequence was found in 6 lesions (6/166, 3.6%). Of patients with carotid artery plaque, MR-predicted IPH was found in 30.8% (12/39) and match lesions with high-signal intensity on DWI and MPRAGE was found in 15.4% (6/39). MR-predicted IPH was significantly higher prevalence in high-grade stenosis group (p=0.010). Relative risk between carotid MPRAGE-positive signal and ipsilateral high-signal intensity on DWI in arteries with carotid artery plaques was 6.8 (p=0.010). Conclusion : Carotid MPRAGE-positive signal in patients was associated with an increased risk of territorial acute infarction as detected objectively by brain DWI. The relative risk of stroke was increased in high-grade stenosis categories.

• Annals of Clinical Neurophysiology
• /
• 제23권2호
• /
• pp.82-91
• /
• 2021

Carotid duplex ultrasound is commonly used to diagnose various carotid artery diseases due to it being noninvasive and easy to perform. Carotid atherosclerosis is a major indicator for the need to perform carotid duplex ultrasound, which can determine the degree of stenosis, plaque characteristics, and intima-media thickness. It can also be used to screen and follow-up after carotid revascularization. Here we discuss the standard techniques, interpretations, and clinical indicators for carotid duplex ultrasounds.

• Journal of Chest Surgery
• /
• 제28권3호
• /
• pp.324-327
• /
• 1995

Extracranial carotid artery disease is rare and closely related to cardiovascular morbidity and mortality.We experienced one case of surgical treatment of left common carotid artery stenosis using internal shunt.The patient was 54-year-old female presented as headache and dizziness for about 2 years.On Doppler ultrasound, an atheromatous plaque was noted along the posteromedial wall of left common carotid artery resulting in luminal narrowing in about 75s of cross section area.The atheroma was resected through carotid endarterectomy, measured about 5.2cm in length. Postoperative course was uneventful and she was discharged in good condition.

• Imaging Science in Dentistry
• /
• 제53권4호
• /
• pp.291-302
• /
• 2023

Purpose: Early detection of carotid stenosis can reduce cardiovascular risk. In this study, the maximum-carotid intima-media thickness (CIMT), the mean-CIMT, and the presence of plaque were examined in healthy young Thai adults. Additionally, correlations between CIMT and cardiovascular risk factors were assessed. Materials and Methods: Left and right carotid arteries of 302 participants(15-45 years old) were scanned, with CIMT measured at the far walls of the common carotid artery, carotid bulb, and internal carotid artery. Demographics and risk factors were assessed using a questionnaire. Ten random participants were re-scanned after 4 weeks. Results: The study included 123 (40.70%) male and 179 (59.30%) female participants. The max-CIMT, mean-CIMT, and plaque thickness were 0.400±0.100, 0.403±0.095 and 1.520±0.814 mm, respectively. Male participants had significantly higher CIMT values for nearly all locations and age groups. The right-sided CIMT values were higher for all locations. The carotid bulb had the greatest CIMT values(0.437±0.178 mm), followed by the common (0.403±0.095 mm) and internal(0.361±0.099 mm) carotid arteries. Plaque was present in 18 locations (1.00%), affecting 15 participants (4.97%). These plaques were found in the right carotid bulb (n=9; 0.50%), left carotid bulb (n=7; 0.39%), and right internal carotid artery (n=2; 0.11%). Adjusted multivariable regression revealed significant positive associations between CIMT and male, increased age and "other" occupation (P<0.05). Conclusion: Both max-CIMT and mean-CIMT were approximately 0.4 mm. Plaque was observed in 4.97% of patients, with an average thickness of 1.5 mm. The most influential risk factors for increased CIMT were sex, age, and occupation.

• 대한의생명과학회지
• /
• 제21권4호
• /
• pp.198-207
• /
• 2015

ST-segment elevation myocardial infarction (STEMI) and chronic total occlusion (CTO) of coronary artery are well-known atherosclerotic vascular diseases. However, the difference of intima-media thickness and plaque characteristics of carotid arteries between STEMI and CTO patients were not directly compared in previous studies. Medical records of a total of 158 (101 STEMI, 57 CTO) patients, who underwent carotid artery ultrasonography, were selected for the analysis. The baseline characteristics, ultrasonography findings, and clinical outcomes of the two groups were compared. The prevalence of hypertension, diabetes mellitus, and dyslipidemia was significantly higher in CTO patients. Carotid intima-media thickness ($0.97{\pm}0.13$ vs. $0.78{\pm}0.17cm$, P < 0.0001) and number of plaques ($2.2{\pm}1.0$ vs. $1.7{\pm}1.2$, P < 0.0001) were greater in CTO than STEMI patients. Multiple (${\geq}3$) or echogenic plaques were more frequently observed in CTO patients. During the median follow-up duration of 27 months, major adverse cardiovascular events occurred in 31% of CTO and 14% of STEMI patients (P = 0.008). We found that, compared with STEMI, CTO patients have higher burden of carotid artery atherosclerosis associated with more comorbid diseases and poor clinical outcomes.

• 한국항행학회논문지
• /
• 제17권1호
• /
• pp.115-122
• /
• 2013

최근 의료영상을 이용한 질병 진단법에 대한 관심이 증가하고 있는 추세이다. 관절경화증은 경동맥의 동맥을 좁게 하여 뇌로 들어가는 혈류의 일부 또는 전체를 차단하는 원인이 된다. 뇌로 흘러가는 혈류가 차단되는 경우 심각한 뇌졸중을 야기하기도 한다. 만일 초기에 경동맥 플라크를 발견하고 이를 치료하면 심각한 뇌졸중을 예방할 수 있다. 본 논문에서는 경동맥의 동맥 초음파 영상에서 경동맥 플라크를 쉽게 발견하기 위한 능동적 윤곽선 추출기법에 기반을 둔 자동 분할기법을 제안한다. 실험에서 사용되는 초음파 영상은 자동 분할기법을 적용하기 전에 적절히 정렬되어있다고 가정한다. 경동맥의 동맥 초음파 영상에 대하여 스네이크 모델을 이용하여 자동분할 방법과 수동분할 방법을 질적 비교한 결과 제안된 방법이 성공적으로 적용되었음을 보여준다. 실험결과 제안된 방법은 방사선사들이 플라크를 쉽게 찾는데 도움을 줄 수 있는 자동화 방법이 될 것으로 예상된다.

• Journal of Yeungnam Medical Science
• /
• 제21권2호
• /
• pp.143-150
• /
• 2004

A thromboembolic stroke is believed to be precipitated by a rupture of vulnerable atheromatous plaques. Until recently the assessment of a further risk of stroke in high-risk patients in whom atherosclerosis has presented with a transient ischaemic attack (TIA), has been confined to a quantitative assessment of the luminal patency of the internal carotid artery. These traditional stratification parameters are no longer believed to be the most accurate predictors of a thrombo-embolism. This is because the process of vessel wall remodeling can maintain a luminal patency, and consequently, quite large friable plaques may remain unidentified. Accordingly, there is a need for an improved risk assessment. The fibrous cap of a vulnerable plaque is thinner, and an intraplaque hemorrhage and inflammation can occur during the development of atherosclerotic plaque. Several imaging methods for identifying vulnerable plaques have been developed. Recently, high resolution magnetic resonance (MR) imaging has emerged as an accurate non-invasive tool that can characterize the carotid plaque components in vivo. A High resolution carotid magnetic resonance is capable of distinguishing an intact, thick fibrous cap from a thin and ruptured cap in carotid plaque. In addition, a plaque MR can identify the active inflammation and detect a hemorrhage. High resolution carotid MR imaging is a valuable noninvasive method for quantifying the plaque components and identifying vulnerable plaque.

• 한국방사선학회논문지
• /
• 제17권3호
• /
• pp.465-472
• /
• 2023

본 연구는 혈관질환을 예측하는 데 있어서 일차 선별검사로서 경동맥 초음파 검사와 혈액학적 검사를 실시한 환자를 대상으로 경동맥 내중막 두께의 변화를 확인하고 죽상경화반의 발현에 위험인자들이 미치는 영향을 알아보고자 하였다. 일개 병원에서 건강검진을 목적으로 내원하여 경동맥 초음파 검사를 실시한 건강한 성인 469명을 대상으로 후향적으로 분석하였다. 그 결과 경동맥 내중막 두께, 연령, 체질량지수, 허리둘레, 수축기 혈압, 총콜레스테롤, 고비중지단백 콜레스테롤, 저비중지단백 콜레스테롤, 공복혈당이 죽상경화반의 유의한 예측인자로 분석되었다(p<0.001). ROC curve 분석을 통해 결정된 죽상경화반 위험인자들의 Cut off value를 기준으로 위험비를 산출하였으며 경동맥 내중막 두께는 8.06배, 연령은 7.53배, 허리둘레는 3.97배, 공복혈당은 2.02배 순으로 높게 나타났다. 따라서 본 연구에서는 죽상경화반의 유무에 영향을 주는 임상학적 위험요인들의 한국인 기준치를 마련할 수 있었으며, 초음파를 이용한 경동맥의 관찰은 심뇌혈관 질환을 조기에 진단하거나 예측하는데 도움이 될 것으로 생각된다.