• Investigative Magnetic Resonance Imaging
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• v.21 no.2
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• pp.71-81
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• 2017

Purpose: To compare three, motion-resistant, T1-weighted MR sequences on the hepatobiliary phase for gadoxetic acid-enhanced MR imaging of the liver. Materials and Methods: In this retrospective study, 79 patients underwent gadoxetic acid-enhanced, 3T liver MR imaging. Fifty-nine were examined using a standard protocol, and 20 were examined using a motion-resistant protocol. During the hepatocyte-specific phase, three MR sequences were acquired: 1) gradient recalled echo (GRE) with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA); 2) radial GRE with the interleaved angle-bisection scheme (ILAB); and 3) radial GRE with golden-angle scheme (GA). Two readers independently assessed images with motion artifacts, streaking artifacts, liver-edge sharpness, hepatic vessel clarity, lesion conspicuity, and overall image quality, using a 5-point scale. The images were assessed by measurement of liver signal-to-noise ratio (SNR), and tumor-to-liver contrast-to-noise ratio (CNR). The results were compared, using repeated post-hoc, paired t-tests with Bonferroni correction and the Wilcoxon signed rank test with Bonferroni correction. Results: In the qualitative analysis of cooperative patients, the results for CAIPIRINHA had significantly higher ratings for streak artifacts, liver-edge sharpness, hepatic vessel clarity, and overall image quality as compared to, radial GRE, (P < 0.016). In the imaging of uncooperative patients, higher scores were recorded for ILAB and GA with respect to all of the qualitative assessments, except for streak artifact, compared with CAIPIRINHA (P < 0.016). However, no significant differences were found between ILAB and GA. For quantitative analysis in uncooperative patients, the mean liver SNR and lesion-to-liver CNR with radial GRE were significantly higher than those of CAIPIRINHA (P < 0.016). Conclusion: In uncooperative patients, the use of the radial GRE sequence can improve the image quality compared to GRE imaging with CAIPIRINHA, despite the data acquisition methods used. The GRE imaging with CAIPIRINHA is applicable for patients without breath-holding difficulties.

• Journal of Veterinary Clinics
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• v.39 no.6
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• pp.326-333
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• 2022

The purpose of this study was to evaluate the radiographic positioning techniques used in local animal hospitals, identify the most common positioning problem, and determine whether there were changes after teleradiology consultations. From September 2016 to April 2021, 15 local animal hospitals that requested radiographic interpretation more than 10 times and for more than six cases of thoracic radiographs were selected. Six sets of two-views of (lateral and ventrodorsal [VD] or dorsoventral [DV] views) digital thoracic radiographs from six dogs per hospital were evaluated in four categories. For the lateral view, radiographic technique scores used in ten local animal hospitals improved, one remained the same, and four became worse. For the VD/DV view, the score for eleven hospitals improved and worsened for four. The most common problem was rotation (57/90) for the lateral view, followed by an inappropriate field of view (59/90), and incorrect beam center (71/90). For the VD/DV view, an inappropriate field of view (54/90) was the most common problem, followed by asymmetry (63/90), and incorrect beam center (73/90). Every factor, except rotation in the lateral view, improved after obtaining technical consultation; however, the degrees of improvement were not remarkable. There was no significant correlation between the number of requests and the degree of improvement. According to the results, the radiographic technique used in local animal hospitals was improved by technical advice on teleradiology. These changes make it possible to provide accurate diagnoses of the requested images. There are some limitations regarding the indicators of evaluation and the number of cases; therefore, further studies that use detailed indicators in large cohort group are needed. In addition, an effective method of teaching should be developed to improve radiographic techniques in local animal hospitals.

• Korean Journal of Radiology
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• v.22 no.8
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• pp.1416-1435
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• 2021

Non-infectious granulomatous lung disease represents a diverse group of disorders characterized by pulmonary opacities associated with granulomatous inflammation, a relatively nonspecific finding commonly encountered by pathologists. Some lesions may present a diagnostic challenge because of nonspecific imaging features; however, recognition of the various imaging manifestations of these disorders in conjunction with patients' clinical history, such as age, symptom onset and duration, immune status, and presence of asthma or cutaneous lesions, is imperative for narrowing the differential diagnosis and determining appropriate management of this rare group of disorders. In this pictorial review, we describe the pathologic findings of various non-infectious granulomatous lung diseases as well as the radiologic features and high-resolution computed tomography imaging features.

• Korean Journal of Digital Imaging in Medicine
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• v.6 no.1
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• pp.65-68
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• 2003

• Korean Journal of Radiology
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• v.24 no.12
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• pp.1303-1305
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• 2023

• Journal of The Korean Radiological Technologist Association
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• v.30 no.1
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• pp.58-62
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• 2004

The purpose of this study was to determine the factors influencing on the size of Radiofrequency ablation using an internally cooled needle electrodes in cattle liver. Ablation procedures involved the use of cool-tip RF system generator and internally coo

• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.266-267
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• 1999

• Investigative Magnetic Resonance Imaging
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• v.25 no.4
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• pp.323-331
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• 2021

Purpose: To investigate the diagnostic criteria of T1-weighted imaging (T1W) and time-of-flight (TOF) imaging for detecting intraplaque hemorrhage (IPH) of a vertebrobasilar artery (VBA) compared with simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) imaging. Materials and Methods: Eighty-seven patients with VBA atherosclerosis who underwent high resolution MR imaging for evaluation of VBA plaque were reviewed. The presence and location of VBA plaque and IPH on SNAP were determined. The signal intensity (SI) of the VBA plaque on T1W and TOF imaging was manually measured and the SI ratio against adjacent muscles was calculated. The receiver-operating characteristic (ROC) curve was used to compare the diagnostic accuracy for detecting VBA IPH. Results: Of 87 patients, 67 had IPH and 20 had no IPH on SNAP. The SI ratio between VBA IPH and temporalis muscle on T1W was significantly higher than that in the no-IPH group (235.9 ± 16.8 vs. 120.0 ± 5.1, P < 0.001). The SI ratio between IPH and temporalis muscle on TOF was also significantly higher than that in the no-IPH group (236.8 ± 13.3 vs. 112.8 ± 7.4, P < 0.001). Diagnostic efficacies of SI ratios on TOF and TIW were excellent (AUC: 0.976 on TOF and 0.964 on T1W; cutoff value: 136.7% for TOF imaging and 135.1% for T1W imaging). Conclusion: Compared with SNAP, cutoff levels of the SI ratio between VBA plaque and temporalis muscle on T1W and TOF imaging for detecting IPH were approximately 1.35 times.

• Journal of Chest Surgery
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• v.53 no.5
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• pp.310-312
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• 2020

Transcatheter leadless pacemaker dislodgment is a rare and potentially fatal complication of leadless device implantation. We present the first case of multidetector computed tomography images of leadless pacemaker migration and embolization in the pulmonary middle lobe artery. The patient was managed by percutaneous retrieval of the dislodged device and re-implantation in the appropriate position.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.05a
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• pp.147-147
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• 2007