• Title/Summary/Keyword: Imaging studies

Search Result 1,610, Processing Time 0.024 seconds

Usefulness of MR Imaging for Diseases of the Small Intestine: Comparison with CT

  • Ji-Hoon Kim;Hyun Kwon Ha;Min Jee Sohn;Byung Suck Shin;Young Suk Lee;Soo Yoon Chung;Pyo Nyun Kim;Moon-Gyu Lee;Yong-Ho Auh
    • Korean Journal of Radiology
    • /
    • v.1 no.1
    • /
    • pp.43-50
    • /
    • 2000
  • Objective: To evaluate the usefulness of MR imaging for diseases of the small intestine, emphasizing a comparison with CT. Materials and Methods: Thirty-four patients who underwent both CT and MR imaging using FLASH 2D and HASTE sequences were analyzed. All patients had various small bowel diseases with variable association of peritoneal lesions. We compared the detectabilities of CT and MR imaging using different MR pulse sequences. The capability for analyzing the characteristics of small intestinal disease was also compared. Results: MR imaging was nearly equal to CT for detecting intraluminal or peritoneal masses, lesions in the bowel and mesentery, and small bowel obstruction, but was definitely inferior for detecting omental lesions. The most successful MR imaging sequence was HASTE for demonstrating bowel wall thickening, coronal FLASH 2D for mesenteric lesions, and axial FLASH 2D for omental lesions. MR imaging yielded greater information than CT in six of 12 inflammatory bowel diseases, while it was equal to CT in six of seven neoplasms and inferior in five of seven mesenteric ischemia. In determining the primary causes of 15 intestinal obstructions, MR imaging was correct in 11 (73%) and CT in nine (60%) patients. Conclusion: MR imaging can serve as an alternative diagnostic tool for patients with suspected inflammatory bowel disease, small intestinal neoplasm or obstruction.

  • PDF

Magnetic Resonance Imaging and Ultrasonographic Evaluation of Canine Tarsus

  • Soomin Park;Sang-hwa Ryu;Jae-gwan Heo;Eun-jee Kim;Jihye Choi;Junghee Yoon
    • Journal of Veterinary Clinics
    • /
    • v.41 no.2
    • /
    • pp.79-87
    • /
    • 2024
  • The tarsus in dogs has a complex structure that makes its evaluation relatively challenging. Because an accurate diagnosis of the tarsus is difficult through basic examinations alone, imaging tests are essential. Previous studies have explored the anatomical and radiological features of the canine tarsus using several imaging modalities. However, the imaging utility of the tarsus across different modalities has not been thoroughly evaluated. This study aimed to visualize the tarsal structures using magnetic resonance imaging (MRI) and ultrasonography, compare their utility, and propose suitable imaging modalities and conditions for evaluating specific tarsal structures. Magnetic resonance imaging and ultrasound scans of the tarsus of four healthy dogs were performed, and two observers rated the utility of each image on a five-point scale. Although MRI is more beneficial for assessing the tarsal structures than ultrasound, ultrasound also appears clinically useful for evaluating the cranial tibialis muscle, deep digital flexor tendon, subcutaneous fat, joint space, and superficial digital flexor tendon. In addition, each structure of interest can be evaluated for optimal visibility using specific ultrasound sections, MRI sequences, and planes. In veterinary clinical practice, an initial assessment using ultrasound imaging with optimal visibility is required and if further evaluation is necessary, MRI examinations with optimal MRI sequences and planes can be performed.

Cardiovascular Magnetic Resonance Versus Histopathologic Study for Diagnosis of Benign and Malignant Cardiac Tumours: A Systematic Review and Meta-Analysis

  • Sandra Nobrega;Catarina Martins da Costa;Ana Filipa Amador;Sofia Justo;Elisabete Martins
    • Journal of Cardiovascular Imaging
    • /
    • v.31 no.4
    • /
    • pp.159-168
    • /
    • 2023
  • BACKGROUND: The gold standard for diagnosis of cardiac tumours is histopathological examination. Cardiovascular magnetic resonance (CMR) is a valuable non-invasive, radiation-free tool for identifying and characterizing cardiac tumours. Our aim is to understand CMR diagnosis of cardiac tumours by distinguishing benign vs. malignant tumours compared to the gold standard. METHODS: A systematic search was performed in the PubMed, Web of Science, and Scopus databases up to December 2022, and the results were reviewed by 2 independent investigators. Studies reporting CMR diagnosis were included in a meta-analysis, and pooled measures were obtained. The risk of bias was assessed using the Quality Assessment Tools from the National Institutes of Health. RESULTS: A total of 2,321 results was obtained; 10 studies were eligible, including one identified by citation search. Eight studies were included in the meta-analysis, which presented a pooled sensitivity of 93% and specificity of 94%, a diagnostic odds ratio of 185, and an area under the curve of 0.98 for CMR diagnosis of benign vs. malignant tumours. Additionally, 4 studies evaluated whether CMR diagnosis of cardiac tumours matched specific histopathological subtypes, with 73.6% achieving the correct diagnosis. CONCLUSIONS: To the best of our knowledge, this is the first published systematic review on CMR diagnosis of cardiac tumours. Compared to histopathological results, the ability to discriminate benign from malignant tumours was good but not outstanding. However, significant heterogeneity may have had an impact on our findings.

Diagnostic Imaging of Biliary Atresia (담도폐쇄증의 영상 진단)

  • Haesung Yoon;Hyun Ji Lim;Jisoo Kim;Mi-Jung Lee
    • Journal of the Korean Society of Radiology
    • /
    • v.83 no.5
    • /
    • pp.991-1002
    • /
    • 2022
  • Biliary atresia is a rare but significant cause of neonatal cholestasis. An early and accurate diagnosis is important for proper management and prognosis. To diagnose biliary atresia, various imaging studies using ultrasonography, MRI, hepatobiliary scans, and cholangiography can be performed, although ultrasonography is more important for initial imaging studies. In this article, we review the findings of biliary atresia from various imaging modalities, including ultrasonography, MRI, hepatobiliary scans, and cholangiography. The known key imaging features include abnormal gallbladder size and shape, periportal thickening visible as a 'triangular cord' sign, invisible common bile duct, increased hepatic arterial flow, and combined anomalies. Aside from the imaging findings of biliary atresia, we also reviewed the diagnostic difficulty in the early neonatal period and the role of imaging in predicting hepatic fibrosis. We hope that this review will aid in the diagnosis of biliary atresia.

Imaging Assessment of Primary Prostate Cancer, Focused on Advanced MR Imaging and PET/CT (자기공명영상과 PET/CT를 중심으로 한 전립선 암의 영상 진단)

  • Jang, Jin-Hee;Byun, Jae-Young;Kim, Min-Sung;Lee, Young-Joon;Oh, Sun-Nam;Rha, Sung-Eun;Yoo, Ie-Ryung
    • Investigative Magnetic Resonance Imaging
    • /
    • v.12 no.2
    • /
    • pp.89-99
    • /
    • 2008
  • Imaging assessment of prostate cancer is one of the most difficult sections of oncology imaging. Detecting, localizing and staging of the primary prostate cancer by preoperative imaging are still challenging for the radiologist. Magnetic resonance (MR) imaging provides excellent soft tissue contrast and is widely used for solid organ imaging, but results of preoperative imaging of the prostate gland with conventional MR imaging is unsatisfactory. Positron emission tomography and computed tomography (PET/CT) is the cornerstone in oncology imaging, but some limitations prohibit the assessment of primary prostate cancer with PET or PET/CT. Recent studies to overcome these insufficient accuracies of imaging evaluation of primary prostate cancers with advanced MR techniques and PET and PET/CT are reported. In this article, we review the imaging findings of prostate cancer on variable modalities, focused on MR imaging and PET/CT.

  • PDF

Brain Iron Imaging in Aging and Cognitive Disorders: MRI Approaches (노화 및 인지기능장애에서 뇌 철 영상 기법: 자기공명영상을 이용한 접근)

  • Jinhee Jang;Junghwa Kang;Yoonho Nam
    • Journal of the Korean Society of Radiology
    • /
    • v.83 no.3
    • /
    • pp.527-537
    • /
    • 2022
  • Iron has a vital role in the human body, including the central nervous system. Increased deposition of iron in the brain has been reported in aging and important neurodegenerative diseases. Owing to the unique magnetic resonance properties of iron, MRI has great potential for in vivo assessment of iron deposition, distribution, and non-invasive quantification. In this paper, we will review the MRI methods for iron assessment and their changes in aging and neurodegenerative diseases, focusing on Alzheimer's disease. In addition, we will summarize the limitations of current approaches and introduce new areas and MRI methods for iron imaging that are expected in the future.

Lung Perfusion Imaging and $Tc^{99m}-Macroaggregated$ Human Serum Albumin

  • Haider, Kh.H.;Ilyas, M.;Hyder, Q.;Kim, Chong-Kook
    • Journal of Pharmaceutical Investigation
    • /
    • v.31 no.2
    • /
    • pp.73-80
    • /
    • 2001
  • Lung perfusion scanning, invariably combined with ventilation studies provides a reliable and non-invasive mean to diagnose lung related pathologies despite the availability of modern techniques such as angiography, magnetic resonance imaging, magnetic resonance angiography, and helical (spiral) computed tomography. The technique involves the generation of images by radiations emitted from radioisotopes introduced in to the lungs. Various radiopharmaceuticals have been proposed and designed to incorporate $Tc^{99m}$ in to macroparticulate form for lung perfusion imaging. However, most of these have associated difficulties such as reproducibility of the product with regards to particle size distribution and poor elimination from the lung capillary bed. $Tc^{99m}$ macroaggregated albumin $(Tc^{99m}-MAA)$ is used extensively for clinical lung perfusion imaging and is considered as the radiopharmaceutical of choice. It is non-toxic, safe, and being biodegradable, is easily eliminated from the lung capillary bed by proteolytic enzyme metabolism and by mechanical forces due to lung movement.

  • PDF

A Review of Brain Magnetic Resonance Imaging Correlates of Successful Cognitive Aging (뇌자기공명영상의 노화에 따른 변화)

  • Ji, Eun-Kyung;Chung, In-Won;Youn, Tak
    • Korean Journal of Biological Psychiatry
    • /
    • v.21 no.1
    • /
    • pp.1-13
    • /
    • 2014
  • Normal aging causes changes in the brain volume, connection, function and cognition. The brain changes with increases in age and difference of gender varies at all levels. Studies about normal brain aging using various brain magnetic resonance imaging (MRI) variables such as gray and white matter structural imaging, proton spectroscopy, apparent diffusion coefficient, diffusion tensor imaging and functional MRI are reviewed. Total volume of brain increases after birth but decreases after 9 years old. During adulthood, total volume of brain is relatively stable. After 35 years old, brain shrinks gradually. The changes of gray and white matters by aging show different features. N-acetylaspartate decreases or remains unchanged but choline, creatine and myo-inositol increase with aging. Apparent diffusion coefficient decreases till 20 years old and then becomes stable during adulthood and increase after 60 years old. Diffusion tensor properties in white matter tissue are variable during aging. Resting-state functional connectivity decreases after middle age. Structural and functional brain changes with normal aging are important for studying various psychiatric diseases such as dementia, schizophrenia and bipolar disorder. Our review may be helpful for studying longitudinal changes of these diseases and successful aging.

Application of MALDI Tissue Imaging of Drugs and Metabolites: A New Frontier for Molecular Histology

  • Shanta, Selina Rahman;Kim, Young-Jun;Kim, Young-Hwan;Kim, Kwang-Pyo
    • Biomolecules & Therapeutics
    • /
    • v.19 no.2
    • /
    • pp.149-154
    • /
    • 2011
  • Matrix assisted laser desorption ionization (MALDI) mass spectrometry is commonly used to analyze biological molecules such as proteins, peptides and lipids from cells or tissue. Recently MALDI Imaging mass spectrometry (IMS) has been widely applied for the identification of different drugs and their metabolites in tissue. This special feature has made MALDI-MS a common choice for investigation of the molecular histology of pathological samples as well as an important alternative to other conventional imaging methods. The basic advantages of MALDI-IMS are its simple technique, rapid acquisition, increased sensitivity and most prominently, its capacity for direct tissue analysis without prior sample preparation. Moreover, with ms/ms analysis, it is possible to acquire structural information of known or unknown analytes directly from tissue sections. In recent years, MALDI-IMS has made enormous advances in the pathological field. Indeed, it is now possible to identify various changes in biological components due to disease states directly on tissue as well as to analyze the effect of treated drugs. In this review, we focus on the advantages of MALDI tissue imaging over traditional methods and highlight some motivating findings that are significant in pathological studies.

Validation of a low-cost portable 3-dimensional face scanner

  • Liu, Catherine;Artopoulos, Andreas
    • Imaging Science in Dentistry
    • /
    • v.49 no.1
    • /
    • pp.35-43
    • /
    • 2019
  • Purpose: The goal of this study was to assess the accuracy and reliability of a low-cost portable scanner (Scanify) for imaging facial casts compared to a previously validated portable digital stereophotogrammetry device (Vectra H1). This in vitro study was performed using 2 facial casts obtained by recording impressions of the authors, at King's College London Academic Centre of Reconstructive Science. Materials and Methods: The casts were marked with anthropometric landmarks, then digitised using Scanify and Vectra H1. Computed tomography (CT) scans of the same casts were performed to verify the validation of Vectra H1. The 3-dimensional (3D) images acquired with each device were compared using linear measurements and 3D surface analysis software. Results: Overall, 91% of the linear Scanify measurements were within 1 mm of the corresponding reference values. The mean overall surface difference between the Scanify and Vectra images was <0.3mm. Significant differences were detected in depth measurements. Merging multiple Scanify images produced significantly greater registration error. Conclusion: Scanify is a very low-cost device that could have clinical applications for facial imaging if imaging errors could be corrected by a future software update or hardware revision.