• Investigative Magnetic Resonance Imaging
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• 제25권4호
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• pp.229-251
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• 2021

Arteriosclerosis is the leading cause of stroke, with a fatality rate surpassing that of ischemic heart disease. High-resolution vessel wall magnetic resonance imaging is generally recognized as a non-invasive and panoramic method for the evaluation of arterial plaque; however, this method requires improved signal-to-noise ratio and scanning speed. Recent advances in high-density head and neck coil arrays are characterized by broad coverage, multiple channels, and closefitting designs. This review analyzes fast magnetic resonance imaging from the perspective of accelerated algorithms for vessel wall imaging and demonstrates the need for effective algorithms for signal acquisition using advanced radiofrequency system. We summarize different phased-array structures under various experimental objectives and equipment conditions, introduce current research results, and propose prospective research studies in the future.

• Annals of Clinical Neurophysiology
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• 제23권1호
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• pp.17-28
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• 2021

The pathogenesis of many strokes originates in the vessel wall. Despite this, most traditional imaging focuses on the vascular lumen. Vessel-wall magnetic resonance imaging (VWMRI) is useful for establishing the etiology of intracranial stenosis. It also provides information regarding atherosclerotic plaque composition and thus plaque vulnerability, which is an indication of its potential to cause a stroke. In this review we focus on the characteristics of VWMRI findings in various arteriopathies related to intracranial artery stenosis, and discuss the clinical implications of these findings.

• Journal of Korean Neurosurgical Society
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• 제58권2호
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• pp.155-158
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• 2015

The equipment and techniques associated with magnetic resonance imaging (MRI) have rapidly evolved. The development of 3.0 Tesla MRI has enabled high-resolution imaging of the intracranial vessel wall. High-resolution MRI (HRMRI) can yield excellent visualization of both the arterial wall and lumen, thus facilitating the detection of the primary and secondary features of intracranial arterial dissection. In the present report, we describe the manner in which HRMRI affected our endovascular treatment planning strategy in 2 cases with unruptured intracranial vertebral artery dissection aneurysm. HRMRI provides further information about the vessel wall and the lumen of the unruptured intracranial vertebral artery dissecting aneurysm, which was treated by an endovascular approach in the 2 current cases.

• Journal of Korean Neurosurgical Society
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• 제65권2호
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• pp.245-254
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• 2022

Objective : The etiology of angiographically occult spontaneous subarachnoid hemorrhage (AOsSAH) is unclear. Three-dimensional (3D) high-resolution vessel wall magnetic resonance imaging (HVM) might be useful in detecting the hidden arterial wall angiopathy in patients with AOsSAH. We aimed to demonstrate the feasibility of HVM for detecting the arterial cause of AOsSAH. Methods : Patients, who were diagnosed with AOsSAH in the first evaluations and underwent HVM, were enrolled. Their clinical and radiologic data were retrospectively reviewed. Especially, focal enhancement of arterial wall on HVM and repetitive catheterized angiograms were precisely compared. Results : Among 251 patients with spontaneous SAH, 22 patients were diagnosed with AOsSAH in the first evaluations (8.76%). After excluding three patients who did not undergo 3D-HVM, 19 patients were enrolled and classified as convexal (n=2) or perimesencephalic (n=4), and diffuse (n=13) groups. In convexal and perimesencephalic groups, no focal enhancement on HVM and no positive findings on repetitive angiography were noted. In diffuse group, 10 patients showed focal enhancement of arterial wall on HVM (10/13, 76.9%). Repeated angiography with 3D reconstruction revealed four patients of angiographically positive causative arteriopathy and possible lesion in one case in the concordant location of intramural enhancement on 3D-HVM (5/10, 50%). Three of them were treated with endovascular stent insertion. All patients, except one, recovered with good clinical outcome (3-month modified Rankin score, 0 and 1). Conclusion : 3D-HVM was useful in detecting hidden true arteriopathy in AOsSAH. It may provide new insights into the etiologic investigation of AOsSAH by proving information about the arterial wall status.

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

• 대한영상의학회지
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• 제81권5호
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• pp.1239-1245
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• 2020

가역성 대뇌 혈관 수축 증후군(reversible cerebral vasoconstriction syndrome)은 벼락두통과 함께 3개월 안에 소실되는 뇌혈관의 다발성 협착을 특징으로 하는 임상적 영상의학적 증후군이다. 해당 환자 중 일부에서 혈관 벽 조영증강이 보고되고 있으나 그 병태생리학적 의미와 진단적 가치는 불분명하다. 이에 혈관 벽 조영증강을 동반한 가역성 대뇌 혈관 수축 증후군의 증례를 보고하고 병태생리학적 의미와 진단적 가치를 고찰하고자 한다.

• 대한영상의학회지
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• 제82권1호
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• pp.261-266
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• 2021

가역적 뇌혈관 수축 증후군은 허혈성 뇌졸중을 야기할 수 있으며 다양한 질환이 원인이 된다. 하지만 빈혈과 가역적 뇌혈관 수축 증후군의 연관성을 나타내는 사례 보고는 거의 없다. 이에 저자들은 보존적 치료로 호전된 66세 여성의 허혈성 뇌졸중과 뇌혈관 수축을 동반한 중증 철결핍빈혈의 사례를 보고하고자 한다. 고해상도 혈관벽 자기공명영상 소견 및 뇌혈관 협착의 가역성을 토대로 가역적 뇌혈관 수축 증후군을 진단할 수 있었다. 가역적 뇌혈관 수축 증후군 및 허혈성 뇌졸중을 가진 환자에서 철결핍빈혈은 하나의 원인으로 고려되어야 하며 즉각적인 처치를 통해 질병의 진행 및 재발을 방지해야 한다.

• Journal of Korean Neurosurgical Society
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• 제64권2호
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• pp.189-197
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• 2021

Objective : This study aims to investigate the relationship between aneurysm wall enhancement and clinical rupture risks based on the magnetic resonance vessel wall imaging (MR-VWI) quantitative methods. Methods : One hundred and eight patients with 127 unruptured aneurysms were prospectively enrolled from Feburary 2016 to October 2017. Aneurysms were divided into high risk (≥10) and intermediate-low risk group (<10) according to the PHASES (Population, Hypertension, Age, Size of aneurysm, Earlier SAH history from another aneurysm, Site of aneurysm) scores. Clinical risk factors, aneurysm morphology, and wall enhancement index (WEI) calculated using 3D MR-VWI were analyzed and compared. Results : In comparison of high-risk and intermediated-low risk groups, univariate analysis showed that neck width (4.5±3.3 mm vs. 3.4±1.7 mm, p=0.002), the presence of wall enhancement (100.0% vs. 62.9%, p<0.001), and WEI (1.6±0.6 vs. 0.8±0.8, p<0.001) were significantly associated with high rupture risk. Multivariate regression analysis revealed that WEI was the most important factor in predicting high rupture risk (odds ratio, 2.6; 95% confidence interval, 1.4-4.9; p=0.002). The receiver operating characteristic (ROC) curve analysis can efficiently differentiate higher risk aneurysms (area under the curve, 0.780; p<0.001) which have a reliable WEI cutoff value (1.04; sensitivity, 0.833; specificity, 0.67) predictive of high rupture risk. Conclusion : Aneurysms with higher rupture risk based on PHASES score demonstrate increased neck width, wall enhancement, and the enhancement intensity. Higher WEI in unruptured aneurysms has a predictive value for increased rupture risk.

• 비파괴검사학회지
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• 제31권5호
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• pp.479-486
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• 2011

의료영상을 기반으로 한 경동맥 분기부 혈류유동장 전산유체역학 해석의 수행에 있어 입구부 경계 조건 도출을 위한 환자 특정 시간 변동 상세 유속 분포를 얻는 것은 일반적으로 쉽지 않다. 그러므로 대부분의 경우 계측된 혈류량을 바탕으로 이상적인 축대칭 완전발달 유속 분포를 적용하게 된다. 그러나 MRI로 직접 계측한 총경동맥 혈류 유속분포를 적용한 기존의 연구에서 입구부 유속분포 경계 조건이 경동맥 분기부 혈류 유동장 해석 결과에 중요한 영향을 미친다는 것을 보였으며, 특히 계측된 혈류 유속분포가 전형적인 Dean type 유동과 다른 독특한 형태를 가진다는 것을 보고하였다. 본 연구에서는 이러한 독특한 형태의 유속 분포가 경동맥 입구부 형상의 이차곡률에 의해 생성됨을 보이고, 직접 경동맥 분기부 유동장 CFD 해석의 경계 조건으로 적용하여 이의 영향을 조사하였다. 이를 통하여 충분한 길이의 실제 경동맥 입구부 형상을 적용 할 경우, 입구부 경계 조건의 영향이 의료영상으로 부터 혈관 형상을 도출하는 과정에서 불가피하게 유기되는 영상 처리 오차에 의한 영향에 비해 상대적으로 크지 않음을 알 수 있었다.

• 대한영상의학회지
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• 제83권1호
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• pp.178-183
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• 2022

진성적혈구증가증은 드문 골수 증식성 질환이며 제어되지 않은 적혈구 생산으로 인해 절대 적혈구 질량이 증가한다. 진성적혈구증가증은 큰 혈관의 협착 또는 폐색과 함께 허혈성 뇌졸중의 위험이 높다. 진성적혈구증가증 환자에서 뇌경색에 대한 많은 증례 보고가 있다. 그러나 합병증으로 뇌졸중이 발생한 진성적혈구증가증 환자의 좁아진 혈관에서 혈관벽 자기공명영상 소견은 보고되지 않았다. 저자들은 뇌졸중으로 인해 입원한 후 PV로 진단된 30세 남성의 경동맥 VW-MRI 소견에 관해 보고하고자 하며, 이는 우리가 아는 한 영어로 된 첫 번째 보고이다.