• Title/Summary/Keyword: magnetic resonance imaging

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Tumor-like Presentation of Tubercular Brain Abscess: Case Report

  • Karki, Dan B.;Gurung, Ghanashyam;Sharma, Mohan R.;Shrestha, Ram K.;Sayami, Gita;Sedain, Gopal;Shrestha, Amina;Ghimire, Ram K.
    • Investigative Magnetic Resonance Imaging
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    • v.19 no.4
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    • pp.231-236
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    • 2015
  • A 17-year-old girl presented with complaints of headache and decreasing vision of one month's duration, without any history of fever, weight loss, or any evidence of an immuno-compromised state. Her neurological examination was normal, except for papilledema. Laboratory investigations were within normal limits, except for a slightly increased Erythrocyte Sedimentation Rate (ESR). Non-contrast computerized tomography of her head revealed complex mass in left frontal lobe with a concentric, slightly hyperdense, thickened wall, and moderate perilesional edema with mass effect. Differential diagnoses considered in this case were pilocytic astrocytoma, metastasis and abscess. Magnetic resonance imaging (MRI) obtained in 3.0 Tesla (3.0T) scanner revealed a lobulated outline cystic mass in the left frontal lobe with two concentric layers of T2 hypointense wall, with T2 hyperintensity between the concentric ring. Moderate perilesional edema and mass effect were seen. Post gadolinium study showed a markedly enhancing irregular wall with some enhancing nodular solid component. No restricted diffusion was seen in this mass in diffusion weighted imaging (DWI). Magnetic resonance spectroscopy (MRS) showed increased lactate and lipid peaks in the central part of this mass, although some areas at the wall and perilesional T2 hyperintensity showed an increased choline peak without significant decrease in N-acetylaspartate (NAA) level. Arterial spin labelling (ASL) and dynamic susceptibility contrast (DSC) enhanced perfusion study showed decrease in relative cerebral blood volume at this region. These features in MRI were suggestive of brain abscess. The patient underwent craniotomy with excision of a grayish nodular lesion. Abundant acid fast bacilli (AFB) in acid fast staining, and epithelioid cell granulomas, caseation necrosis and Langhans giant cells in histopathology, were conclusive of tubercular abscess. Tubercular brain abscess is a rare manifestation that simulates malignancy and cause diagnostic dilemma. MRI along with MRS and magnetic resonance perfusion studies, are powerful tools to differentiate lesions in such equivocal cases.

In Vivo Reporter Gene Imaging: Recent Progress of PET and Optical Imaging Approaches

  • Min, Jung-Joon
    • Bioinformatics and Biosystems
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    • v.1 no.1
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    • pp.17-27
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    • 2006
  • Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene delivery and/or expression. This article reviews the use of radionuclide, magnetic resonance, and optical imaging technologies as they have been used in imaging gene delivery and gene expression for molecular imaging applications. The studies published to date demonstrate that noninvasive imaging tools will help to accelerate pre-clinical model validation as well as allow for clinical monitoring of human diseases.

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Characteristics of Pediatric Pancreatitis on Magnetic Resonance Cholangiopancreatography

  • Hwang, Jae-Yeon;Yoon, Hye-Kyung;Kim, Kyung Mo
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.18 no.2
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    • pp.73-84
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    • 2015
  • Pediatric pancreatitis is not uncommon and results in considerable morbidity and mortality in the affected children. Unlike adults, pediatric pancreatitis is more frequently associated with underlying structural abnormalities, trauma, and drugs rather than an idiopathic etiology. Magnetic resonance cholangiopancreatography (MRCP) is a good imaging modality for evaluating pancreatitis and determining etiology without exposure to radiation. This article focuses on MRCP findings associated with various causes of pancreatitis in children, particularly structural abnormalities of the pancreaticobiliary system, as well as describing the feasibility, limitations, and solutions associated with pediatric MRCP.

Microwave and RF Heating for Medical Application under Noninvasive Temperature Measurement Using Magnetic Resonance

  • Nikawa, Yoshio;Ishikawa, Akira
    • Journal of electromagnetic engineering and science
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    • v.10 no.4
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    • pp.244-249
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    • 2010
  • Recent development of magnetic resonance imaging (MRI) equipment enables interventional radiology (IVR) as diagnosis and treatment under MRI usage. In this paper, a new methodology for magnetic resonance (MR) scanner to apply not only diagnostic equipment but for treatment one is discussed. The temperature measuring procedure under MR is to measure phase shift of $T_1$, which is the longitudinal relaxation time of proton, for the position inside a sample material with the application of pulsed RF for heating inside the sample as artificial dielectrics. The result shows the possibility to apply MR as temperature measuring equipment and as a heating equipment for applying such as hyperthermia heating modality.

The MRI Findings of Flexor Digitorum Accessorius Longus Muscle: a Case Report

  • Shin, Jae Hwan;Shim, Jae-Chan;Lee, Kyoung Eun;Kim, Ho Kyun;Lee, Ghi Jai;Suh, Jung Ho
    • Investigative Magnetic Resonance Imaging
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    • v.20 no.2
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    • pp.123-126
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    • 2016
  • The flexor digitorum accessorius longus (FDAL) is the most common accessory muscle found in the posterior compartment of the ankle area. The accessory muscle in this area such as the FDAL may be incidentally identified on magnetic resonance images (MRI). There are some case reports about the FDAL in cadaver researches. However, the MRI findings about the FDAL have been reported in a few cases. In this paper, we report a case of the FDAL incidentally identified on MRI with review of the literature about the FDAL.

Liver MRI Protocol (간의 자기공명영상 프로토를)

  • 김용우;이석홍
    • Investigative Magnetic Resonance Imaging
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    • v.4 no.1
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    • pp.1-6
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    • 2000
  • Protocol이란 Dorland의 의학사전에 의하면 "어떤 술기의 절차에 대한 명백하고 상세한 계획서(an explicit detiled plan of a procedure)"로 정의된다. 그래서 liver MR imaging protocol은 간에 발생한 병적 문제를 해결하기 위해서, 자기공명 영상술을 실시하는 구체적이고 세부적인 지침서를 말하게 된다. 그러나 현실적으로 병원에 따라 imaging protocol은 조금씩 다르다. 왜냐하면 자기공명영상 장비가 다르고, 적절한 펄스파형(pulse sequence)에 대한 통일된 안이 없기 때문이다. 자기공명영상술은 지금도 계속해서 빠르게 발전하고 있기 때문에, 현재 통용되는 영상 술기에 대한 자세한 지침은 곧 소용이 없게 된다. 그래서 본 소고에서는 간의 자기공명영상화의 병변의 특성화에 대한 기본적인 면에 더욱 중점을 두고 기술하고자 한다.

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Tenosynovial Giant Cell Tumor Showing Severe Bone Erosion in the Finger: Case Report and Review of the Imaging Findings and Their Significance

  • Lee, Kyung Ryeol;Hyun, Chang Lim
    • Investigative Magnetic Resonance Imaging
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    • v.20 no.2
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    • pp.127-131
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    • 2016
  • We report a case of tenosynovial giant cell tumor with severe bone erosion in the right fifth finger of a 46-year-old man. Throughout this case review, we describe the imaging findings of tenosynovial giant cell tumor with severe bone erosion and review the literatures regarding osseous lesions caused by tenosynovial giant cell tumor and their significance related to the differential diagnosis and patient treatment.

Collison Tumor of Adenocarcinoma and Diffuse Large B-Cell Lymphoma in the Rectum: a Case Report and Literature Review

  • Kim, See Hyung
    • Investigative Magnetic Resonance Imaging
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    • v.23 no.4
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    • pp.374-380
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    • 2019
  • Collision tumor is a synchronous neoplasm wherein two histologically distinct tumors co-exist within the same anastomosis site. Collision tumor can occur in any organ, but the incidence is markedly rare. Additionally, preoperative diagnosis can be challenging to the radiologist. Herein, we report an age 60 male with collision tumor of rectal adenocarcinoma and diffuse large B-cell lymphoma, presented as a semi-annular wall thickening and bulky exophytic mass on MR imaging.

Recent Developments in Magnetic Resonance Imaging (최근 자기공명 의료영상기기의 발전)

  • Cho, Z.H.;Ro, Y.M.;Chung, S.C.;Park, S.H.;Mun, C.W.
    • Proceedings of the KOSOMBE Conference
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    • v.1994 no.05
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    • pp.9-15
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    • 1994
  • In last few decades, medical imaging techniques have been developed startling progress. Especially in MRI (Magnetic Resonance Imaging), many imaging techniques such as chemical shift imaging, flow imaging, diffusion and perfusion imaging, fast imaging, susceptibility imaging and functional imaging have been studied and many of them were well known as useful diagnostic instruments. In this paper, recently developing techniques, i.e., NMR microscopy, fringe field imaging and functional imaging will be presented.

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Cetyl Trimethyl Ammonium Bromide-coated Nickel Ferrite Nanoparticles for Magnetic Hyperthermia and T2 Contrast Agents in Magnetic Resonance Imaging

  • Lee, Da-Aemm;Bae, Hongsubm;Rhee, Ilsum
    • Journal of the Korean Physical Society
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    • v.73 no.9
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    • pp.1334-1339
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    • 2018
  • Spherical nickel ferrite nanoparticles were synthesized using the thermal decomposition method and coated with cetyl trimethyl ammonium bromide (CTAB) after the synthesis. Transmission electron microscopy images showed that the average diameter of the particles was 9.40 nm. The status of the CTAB-coating on the surface of the particles was checked using Fourier-transform infrared spectroscopy. Their hysteresis curve showed that the particles exhibited a superparamagnetic behavior. The $T_1$ and the $T_2$ relaxations of the nuclear spins were observed in aqueous solutions of the particles with different particles concentrations by using a magnetic resonance imaging (MRI) scanner, which showed that the $T_1$ and the $T_2$ relaxivities of the particles in water were $0.57mM^{-1}{\cdot}s^{-1}$ and $10.42mM^{-1}{\cdot}s^{-1}$, respectively. In addition, using an induction heating system, we evaluated their potentials for magnetic hyperthermia applications. The aqueous solution of the particles with a moderate concentration (smaller than 6.5 mg/mL) showed a saturation temperature larger than the hyperthermia target temperature of $42^{\circ}C$. These findings show that the CTAB-coated nickel ferrite particles are suitable for applications as $T_2$ contrast agents in MRI and heat generators in magnetic hyperthermia.