• Investigative Magnetic Resonance Imaging
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• 제25권3호
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• pp.197-200
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• 2021

Ramsay Hunt syndrome (RHS) is a disease caused by varicella-zoster virus (VZV) infection that can be diagnosed through clinical symptoms with or without imaging evaluations. The typical features of RHS on imaging evaluation include signal changes and enhancement in the internal auditory canal (IAC) nerves, and the labyrinthine segment of cranial nerve VII (CN VII) and cranial nerve VIII (CN VIII). In some patients, inner ear structure (cochlear and vestibular apparatus) is involved in RHS. Neurologic complications, such as encephalitis and meningitis, are rare in RHS, but are known to occur. Therefore, magnetic resonance imaging (MRI) is necessary to detect both abnormal signal intensity in the IAC, CN VII, CN VIII, inner and ear structure, and CNS complications. We report an RHS patient with CN VII, VIII, and leptomeningeal enhancement within the cerebellar folia on 10-min delayed, contrast-enhanced (CE), three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) imaging.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3821-3823
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• 2011

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.597-599
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• 1998

The clinical acceptance of magnetic resonance imaging(MRI) system has been more rapid than that of the other medical image diagnosis system(X-ray, CT, etc) with the advantage of nonhazardous nature, high resolution capability, potential for chemically specified imaging. MRI system is composed of super conducting magnet, gradient fields, rf transceiver, system controller and imaging software technology. In this paper, introducing the principle of magnetic resonance imaging, it proposes the implementation of PC-based MRI system.

• Applied Microscopy
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• 제46권4호
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• pp.179-183
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• 2016

Mapping brain structural and functional connections through the whole brain is essential for understanding brain mechanisms and the physiological bases of brain diseases. Although region specific structural or functional deficits cause brain diseases, the changes of interregional connections could also be important factors of brain diseases. This review will introduce common neuroimaging modalities, including structural magnetic resonance imaging (MRI), functional MRI (fMRI), diffusion tensor imaging, and other recent neuroimaging analyses methods, such as voxel-based morphometry, cortical thickness analysis, local gyrification index, and shape analysis for structural imaging. Tract-Based Spatial Statistics, TRActs Constrained by UnderLying Anatomy for diffusion MRI, and independent component analysis for fMRI also will also be introduced.

• 대한수의학회지
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• 제63권4호
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• pp.39.1-39.5
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• 2023

A 14-year-old, spayed female, poodle was presented with dysuria and hematuria. A mass that appeared hypoechoic on ultrasound and hypoattenuating on computed tomography (CT) extended from the bladder neck to the urethra. Magnetic resonance imaging (MRI) showed the mass invading the muscular layer of the bladder, urethra, and prostate with distinct margins. Transitional cell carcinoma (TCC) was confirmed with the CADET-BRAF test. This study describes the CT and MRI features of suspected TCC lesions involving the bladder, prostate, and urethra. MRI showed superior soft tissue contrast resolution, enabling evaluation of invasion of the muscular layer of the bladder and urethra.

• Korean Journal of Radiology
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• 제22권2호
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• pp.243-252
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• 2021

Objective: To compare and correlate the findings of intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging and arterial spin labeling (ASL) imaging in characterizing parotid gland tumors. Materials and Methods: We retrospectively reviewed 56 patients with parotid gland tumors evaluated by MR imaging. The true diffusion coefficient (D), pseudo-diffusion coefficient (D^*), and fraction of perfusion (f) values of IVIM imaging and tumor-to-parotid gland signal intensity ratio (SIR) on ASL imaging were calculated. Spearman rank correlation coefficient, chi-squared, Mann-Whitney U, and Kruskal-Wallis tests with the post-hoc Dunn-Bonferroni method and receiver operating characteristic curve assessments were used for statistical analysis. Results: Malignant parotid gland tumors showed significantly lower D than benign tumors (p = 0.019). Within subgroup analyses, pleomorphic adenomas (PAs) showed significantly higher D than malignant tumors (MTs) and Warthin's tumors (WTs) (p < 0.001). The D^* of WTs was significantly higher than that of PAs (p = 0.031). The f and SIR on ASL imaging of WTs were significantly higher than those of MTs and PAs (p < 0.05). Significantly positive correlation was found between SIR on ASL imaging and f (r = 0.446, p = 0.001). In comparison with f, SIR on ASL imaging showed a higher area under curve (0.853 vs. 0.891) in discriminating MTs from WTs, although the difference was not significant (p = 0.720). Conclusion: IVIM and ASL imaging could help differentiate parotid gland tumors. SIR on ASL imaging showed a significantly positive correlation with f. ASL imaging might hold potential to improve the ability to discriminate MTs from WTs.

• Investigative Magnetic Resonance Imaging
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• 제21권2호
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• pp.119-124
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• 2017

Chromophobe renal cell carcinoma (RCC) is an uncommon subtype of RCC having a better prognosis than clear cell RCC. Although there are several reports of seeding metastasis of RCC after biopsy, seeding metastasis of chromophobe RCC after surgical resection has seldom been reported. Here, we describe a case of multiple seeding metastases in the abdomen and pelvis 78 months after robot-assisted laparoscopic partial nephrectomy, without prior history of biopsy for chromophobe RCC in the right kidney. As magnetic resonance imaging (MRI) of the pelvic mass showed a similar appearance to the primary renal mass and displayed separate margins with the rectum and prostate gland, we were able to make a diagnosis before pathologic confirmation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제18권3호
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• pp.149-159
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• 2015

Crohn's disease is a chronic idiopathic inflammatory disease of the intestines characterized by frequent relapse and remission. It often develops in children and adolescents, who are vulnerable to repeated exposure to ionizing radiations. Magnetic resonance enterography (MRE) is an increasingly important radiation-free imaging modality that is used to evaluate pediatric patients with Crohn's disease. MRE can evaluate extraluminal and extraintestinal abnormalities as well as the status of the bowel wall. In addition, MRE has an advantage in the evaluation of the small bowel involvement. MRE can be used for the initial diagnosis of Crohn's disease, and can aid in the assessment of disease activity and complications such as penetrating and fibrostenotic diseases. The aims of this article are to review the MRE technique for obtaining diagnostic and high-quality images and to discuss interpretations of imaging findings in patients with Crohn's disease.

• Investigative Magnetic Resonance Imaging
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• 제17권1호
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• pp.47-49
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• 2013

내인성안구염은 외부 혹은 내부의 원인으로 인한 안구 내의 염증반응으로 생기는 드문 질환이다. 자기공명영상은 안구염의 진단과 뇌농양의 진단에 모두 유용한 것으로 알려져 있다. 저자들은 내인성안구염과 함께 뇌농양이 동시에 병발된 예가 있어 자기공명영상 소견과 함께 보고하고자 한다.

• 한국자기공명학회논문지
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• 제19권3호
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• pp.124-131
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• 2015

Hyperpolarization methods are the most emerging techniques in the field of magnetic resonance (MR) researches since they make a contribution to overcoming sensitivity limitation of MR spectroscopy and imaging, leading to new fields of researches, real-time in vivo metabolic/molecular imaging and MR analysis of chemical/biological reactions in non-equilibrium conditions. Make use of enormous signal enrichments, it becomes feasible to investigate various chemical and biochemical systems with low ${\gamma}$ nuclei in real-time. This review deals with the theoretical principals of common hyperpolarization methods and their experimental features. In addition, more detailed theories, mechanisms, and applications of dissolution dynamic nuclear polarization (D-DNP) are discussed.