• Journal of radiological science and technology
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• v.42 no.5
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• pp.351-356
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• 2019

This study aimed to determine whether there was a difference in measurements between North American Symptomatic Carotid Endarterectomy Trial(NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease(WASID) methods that measure the middle cerebral artery stenosis in Digital Subtraction Angiography (DSA) and Magnetic Resonance Angiography (MRA). It involved 24 patients who had completed both DSA and MRA among patients with Middle Cerebral Artery (MCA) stenosis. The Middle Cerebral Artery (MCA) stenosis was measured using the NASCET and WASID methods through a retrospective analysis. For the NASCET and WASID methods, they performed measurements on normal blood vessels located far from and close to the stenosis, respectively. The mean value and standard deviation of the Digital Subtraction Angiography (DSA) measured by the NASCET method were 59.23% and 13.27%. On the other hand, those of the Digital Subtraction Angiography (DSA) measured by the WASID method were 66.64% and 12.47%. And, the mean value and standard deviation of the Magnetic Resonance Angiography (MRA) measured by the NASCET method were 49.82% and 12.06%. By contrast, those of the Magnetic Resonance Angiography (MRA) measured by the WASID method were 56.63% and 10.67%. All the p-values obtained by the Pearson and Spearman correlation tests in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) were <0.01. In conclusion, this study suggests that both the NASCET and WASID methods to measure the middle cerebral artery stenosis in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) can be used if they are not used interchangeably.

• Imaging Science in Dentistry
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• v.51 no.3
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• pp.329-332
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• 2021

A markedly enlarged foramen transversarium was discovered incidentally on a cone-beam computed tomography scan of a 72-year-old male patient who was referred for dental implant placement. Further evaluation with magnetic resonance angiography revealed that the foramen enlargement was caused by a tortuosity in the course of the vertebral artery. This case report highlights the importance of recognizing significant incidental findings on diagnostic images and the potential need for additional imaging as part of the complete interpretative process.

• Investigative Magnetic Resonance Imaging
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• v.22 no.1
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• pp.71-77
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• 2018

Purpose: To develop a two-dimensional (2D) image-based respiratory motion correction technique for free-breathing coronary magnetic resonance angiography (MRA). Materials and Methods: The proposed respiratory navigator obtained aliased a 2D sagittal image from under-sampled k-space data and utilized motion correlation between the aliased images. The proposed navigator was incorporated into the conventional coronary MRA sequence including the diaphragm navigator and tested in three healthy subjects. Results: The delineation of major coronary arteries was significantly improved using the proposed 2D motion correction (S/I and A/P) compared to one-dimensional (S/I) correction using the conventional diaphragm navigator. Conclusion: The 2D image-based respiratory navigator was proposed for free-breathing coronary angiography and showed the potential for improving respiratory motion correction compared to the conventional 1D correction.

• Investigative Magnetic Resonance Imaging
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• v.25 no.4
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• pp.209-217
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• 2021

Magnetic resonance angiography (MRA) plays an important role in accurate diagnosis and appropriate treatment planning for patients with arterial disease. Contrast-enhanced (CE) MRA is fast and robust, offering hemodynamic information of arterial flow, but involves the risk of a side effect called nephrogenic systemic fibrosis. Various non-contrast-enhanced (NCE) MRA techniques have been developed by utilizing the fact that arterial blood is moving fast compared to background tissues. NCE MRA is completely free of any safety issues, but has different drawbacks for various approaches. This review article describes basic principles of CE and NCE MRA techniques with a focus on how to generate angiographic image contrast from a pulse sequence perspective. Advantages, pitfalls, and key applications are also discussed for each MRA method.

• Journal of Korean Neurosurgical Society
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• v.37 no.2
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• pp.101-104
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• 2005

Objective: A persistent trigeminal artery (PTA) may be found incidentally on conventional cerebral angiography and magnetic resonance(MR) angiography. Our goal is to examine the course and relationships of the vessel to the surrounding structures. Methods: Cerebral angiography was performed in 494 patients and MRA in 880; the patients had or were suspected to have cerebrovascular disease. In the images, the incidence, origin, course, and relationships of the PTA were evaluated. Results: A PTA was found in two (0.4%) of the patients undergoing cerebral angiography and three (0.34%) receiving an MR angiography. In four patients, the PTA arose from the lateral part of the cavernous segment of the internal carotid artery, then passed caudally and around the base of the dorsum sellae. In the other patient, the PTA arose from the medial aspect of the siphon, and ascended sharply to pierce the dorsum sellae and join the basilar artery. In four cases, there was hypoplasia of a proximal basilar artery below the abnormal communication; the vessel was of increased diameter above the communication. Conclusion: Identification of a PTA with a trans-sellar course is crucial if trans-sphenoidal surgery is planned. Hypoplasia of a proximal basilar artery should not be mistaken for an acquired narrowing.

• Journal of Korean Neurosurgical Society
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• v.37 no.4
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• pp.263-267
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• 2005

Objective: Middle cerebral artery(MCA) anomalies are found incidentally on conventional cerebral angiography and magnetic resonance angiography(MRA). Our goal is to examine the incidence and types of MCA anomalies. Methods: Cerebral angiography was performed in 448 patients and MRA in 743; the patients had or were suspected to have cerebrovascular disease. The images were retrospectively evaluated for arterial anatomic anomalies. We use Teal's classification for definition of accessory and duplicated MCAs. Results: On cerebral angiography, the following anomalies of the MCA were found in seven patients: fenestration (n = 2, incidence = 0.45%); duplication (n = 2, incidence = 0.45%); accessory MCA (n = 2, incidence = 0.45%); aplasia (n = 1, incidence = 0.22%). On MRA, eight patients had anomalous MCAs : fenestration (n = 1, incidence = 0.14%); duplication (n= 6, incidence = 0.81%); accessory (n = 1, incidence = 0.14%). Conclusion: Although the clinical significance is not great, we find a relatively high incidence of anomalous MCAs. Knowledge and recognition of these MCA anomalies are useful and important in the interpretation of cerebral images and during neurosurgical procedures.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.4
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• pp.291-298
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• 2003

It is important to visualize a lesion accurately in diagnosis of disease. Many diseases result in a change of lesion. Magnetic resonance angiography can visualize the morphological characteristics of blood vessel. The magnetic resonance angiography (MRA) can be categorized to time-of-flight, phase contrast, and contrast enhanced MRA. In this paper, we introduce a principle, sequence, and feature of angiography For better image quality we describe data processing methods and show several applications to human bodies

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.117-122
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• 2002

Contrast-enhanced MR angiography has become a widely used method useful for clinical diagnosis. Early studies identified a number of technical issues, and many of these have been addressed with various MRI physics innovations over the last several years. The quality of the results is high enough that CE MRA is replacing conventional x-ray angiography methods at many institutions. Ongoing research is expected to provide further improvements in performance, most notably in additional reductions in examination time, in time-resolved 3D imaging, and in improved imaging of the peripheral vasculature with extended fields of view.

• Proceedings of the KSMRM Conference
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• 2000.11a
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• pp.74-74
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• 2000

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.578-581
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• 2007

Moyamoya disease is characterized by the angiographic findings of bilateral occlusion of the distal portion of the internal carotid arteries with a vascular network at the base of the brain. The typical findings on conventional angiography and magnetic resonance imaging usually confirm the correct diagnosis of moyamoya disease. We experienced a 11-year-old girl with moyamoya disease showing repeated transient ischemic attacks and we report on this case with a review of the literature.