OBJECTIVE: This study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency. MATERIALS AND METHODS: Between May 2005 and June 2014, after stent placement for the treatment of IVCS with acute ilio-femoral deep vein thrombosis, follow-up CT venography was performed in 48 patients (35 women, 13 men; age range 23-87 years; median age 56 years). Using follow-up CT venography, the degree of the stent compression was calculated and used to divide patients into two groups. Possible factors associated with stent compression and patency were evaluated. The cumulative degree of stent compression and patency rate were analyzed. RESULTS: All of the stents used were laser-cut nitinol stents. The proportion of limbs showing significant stent compression was 33%. Fifty-six percent of limbs in the significant stent compression group developed stent occlusion. On the other hand, only 9% of limbs in the insignificant stent compression group developed stent occlusion. Significant stent compression was inversely correlated with stent patency (p < 0.001). The median patency period evaluated with Kaplan-Meier analysis was 20.0 months for patients with significant stent compression. Other factors including gender, age, and type of stent were not correlated with stent patency. Significant stent compression occurred most frequently (87.5%) at the upper end of the stent (ilio-caval junction). CONCLUSION: Significant compression of nitinol stents placed in IVCS highly affects stent patency. Therefore, in order to prevent stent compression in IVCS, nitinol stents with higher radial resistive force may be required.
Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Iliac Vein/pathology/*radiography ; Kaplan-Meier Estimate ; Male ; May-Thurner Syndrome/*diagnosis/radiography/*therapy ; Middle Aged ; Phlebography ; Retrospective Studies ; Stents/adverse effects ; Tomography, X-Ray Computed ; Treatment Outcome ; Vascular Patency/*physiology ; Venous Thrombosis/radiography/*therapy ; Young Adult

Peripheral arterial occlusive disease caused by atherosclerosis can present with intermittent claudication or critical limb ischemia. Proper diagnosis and management is warranted to improve symptoms and salvage limbs. With the introduction of new techniques and dedicated materials, endovascular recanalization is widely performed for the treatment of peripheral arterial occlusive disease because it is less invasive than surgery. However, there are various opinions regarding the appropriate indications and procedure methods for interventional recanalization according to operator and institution in Korea. Therefore, we intend to provide evidence based guidelines for interventional recanalization by multidisciplinary consensus. These guidelines are the result of a close collaboration between physicians from many different areas of expertise including interventional radiology, interventional cardiology, and vascular surgery. The goal of these guidelines is to ensure better treatment, to serve as a guide to the clinician, and consequently, to contribute to public health care.
Arterial Occlusive Diseases/radiography/*therapy ; Arteries/pathology ; Endovascular Procedures/*standards ; Humans ; Intermittent Claudication/radiography/therapy ; Limb Salvage/methods ; Lower Extremity/*blood supply ; Peripheral Arterial Disease/radiography/*therapy ; *Practice Guidelines as Topic ; Republic of Korea

In patients with non-ischemic cardiomyopathy (NICM), risk stratification for sudden cardiac death (SCD) and selection of patients who would benefit from prophylactic implantable cardioverter-defibrillators remains challenging. We aim to discuss the evidence of cardiac magnetic resonance (CMR)-derived myocardial scar for the prediction of adverse cardiovascular outcomes in NICM. From the 15 studies analyzed, with a total of 2747 patients, the average prevalence of myocardial scar was 41%. In patients with myocardial scar, the risk for adverse cardiac events was more than 3-fold higher, and risk for arrhythmic events 5-fold higher, as compared to patients without scar. Based on the available observational, single center studies, CMR scar assessment may be a promising new tool for SCD risk stratification, which merits further investigation.
Arrhythmias, Cardiac/*diagnosis ; Cardiomyopathies/*diagnosis ; Cicatrix/*diagnosis ; Death, Sudden, Cardiac ; Defibrillators, Implantable ; Female ; Humans ; Magnetic Resonance Imaging, Cine/*methods ; Myocardium/pathology ; Risk Assessment ; Risk Factors

No abstract available.
Appendicitis* ; Appendix ; Immunoglobulins*

OBJECTIVE: To assess the current practice patterns of radiologists who perform transthoracic needle biopsy (TNB). MATERIALS AND METHODS: An email survey of 71 questions on TNB was sent to 240 members of the Korean Society of Thoracic Radiology. The answers to multiple-choice questions (n = 56) were analyzed. RESULTS: Of 60 respondents, 45% had 10 or more years of experience in chest radiology, and 70% had 5 or more years of experience in TNB. For the question on the most frequently used diagnostic method for lesions with high probability of being resectable-stage lung cancer, 70% of respondents answered that TNB is initially used, with or without bronchoscopy. In patients at high-risk of TNB-related complications, the proportion of the respondents who consistently declined TNB was only 5%. The number of rebiopsies was said to be increased; molecular analysis for an established target therapy (43.6%) and clinical trial of a new drug (28.2%) were the two most common reasons for it. The most popular needle type was the coaxial cutting needle (55%), and the popular guiding modality was conventional computed tomography (CT) (56.7%). In addition, 15% of respondents have encountered air embolism. CONCLUSION: Despite high variation in how TNB is being performed in Korea, some patterns were noted. It is common for patients with resectable-stage lung cancer to undergo TNB prior to surgery. Rebiopsy is now more common than before, with personalized medicine as the most important reason for it. The most popular type of needle is the coaxial system; the most popular modality for guidance is still CT.
Biopsy, Needle* ; Bronchoscopy ; Electronic Mail ; Embolism, Air ; Humans ; Korea ; Lung Neoplasms ; Methods ; Needles* ; Precision Medicine ; Surveys and Questionnaires ; Thorax

One of the major problems radiologists face in everyday practice is to decide the correct diagnosis, or at least narrow down the list of possibilities. In this context, indicative evidences (signs) are useful to recognize pathologies, and also to narrow the list of differential diagnoses. Despite classically being described for a single disease, or a closely related family of disorders, most indications are not restricted exclusively to their traditional definition. Therefore, using signs for prognosis requires knowledge of the mechanism of their appearance, and which pathologies they are observed in. In this study, we demonstrate some of the more common and useful neuroradiologic signs with relevant images, and discuss their use in differential diagnosis.
Brain ; Diagnosis ; Diagnosis, Differential ; Humans ; Magnetic Resonance Imaging ; Pathology ; Prognosis ; Ultrasonography

OBJECTIVE: To identify potential imaging biomarkers of Alzheimer's disease by combining brain cortical thickness (CThk) and functional connectivity and to validate this model's diagnostic accuracy in a validation set. MATERIALS AND METHODS: Data from 98 subjects was retrospectively reviewed, including a study set (n = 63) and a validation set from the Alzheimer's Disease Neuroimaging Initiative (n = 35). From each subject, data for CThk and functional connectivity of the default mode network was extracted from structural T1-weighted and resting-state functional magnetic resonance imaging. Cortical regions with significant differences between patients and healthy controls in the correlation of CThk and functional connectivity were identified in the study set. The diagnostic accuracy of functional connectivity measures combined with CThk in the identified regions was evaluated against that in the medial temporal lobes using the validation set and application of a support vector machine. RESULTS: Group-wise differences in the correlation of CThk and default mode network functional connectivity were identified in the superior temporal (p < 0.001) and supramarginal gyrus (p = 0.007) of the left cerebral hemisphere. Default mode network functional connectivity combined with the CThk of those two regions were more accurate than that combined with the CThk of both medial temporal lobes (91.7% vs. 75%). CONCLUSION: Combining functional information with CThk of the superior temporal and supramarginal gyri in the left cerebral hemisphere improves diagnostic accuracy, making it a potential imaging biomarker for Alzheimer's disease.
Alzheimer Disease* ; Biomarkers ; Brain ; Cerebrum ; Humans ; Magnetic Resonance Imaging ; Neuroimaging* ; Parietal Lobe ; Retrospective Studies ; Support Vector Machine ; Temporal Lobe

OBJECTIVE: To compare the contrast-enhanced fluid-attenuated inversion recovery (CE-FLAIR), the CE T1-weighted (CE-T1W) sequence with fat suppression (FS) and magnetization transfer (MT) for early detection and characterization of infectious meningitis. MATERIALS AND METHODS: Fifty patients and 10 control subjects were evaluated with the CE-FLAIR and the CE-T1W sequences with FS and MT. Qualitative assessment was done by two observers for presence and grading of abnormal leptomeningeal enhancement. Quantitative assessment included computation of net meningeal enhancement, using single pixel signal intensity software. A newly devised FLAIR based scoring system, based on certain imaging features including ventricular dilatation, ependymal enhancement, infarcts and subdural effusions was used to indicate the etiology. Data were analysed using the Student's t test, Cohen's Kappa coefficient, Pearson's correlation coefficient, the intraclass correlation coefficient, one way analysis of variance, and Fisher's exact test with Bonferroni correction as the post hoc test. RESULTS: The CE-FLAIR sequence demonstrated a better sensitivity (100%), diagnostic accuracy (95%), and a stronger correlation with the cerebrospinal fluid, total leukocyte count (r = 0.75), protein (r = 0.77), adenosine deaminase (r = 0.81) and blood glucose (r = -0.6) values compared to the CE-T1W sequences. Qualitative grades and quantitative meningeal enhancement on the CE-FLAIR sequence were also significantly greater than those on the other sequences. The FLAIR based scoring system yielded a diagnostic accuracy of 91.6% and a sensitivity of 96%. A strong inverse Pearson's correlation (r = -0.95) was found between the assigned score and patient's Glasgow Coma Scale at the time of admission. CONCLUSION: The CE-FLAIR sequence is better suited for evaluating infectious meningitis and could be included as a part of the routine MR imaging protocol.
Adenosine Deaminase ; Blood Glucose ; Cerebrospinal Fluid ; Dilatation ; Glasgow Coma Scale ; Humans ; Leukocyte Count ; Magnetic Resonance Imaging ; Meningitis*

OBJECTIVE: To evaluate the utility of high-resolution vessel wall imaging (HR-VWI) of middle cerebral artery (MCA), and to compare HR-VWI findings between striatocapsular infarction (SC-I) and lenticulostriate infarction (LS-I). MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board, and informed consent was waived. From July 2009 to February 2012, 145 consecutive patients with deep subcortical infarctions (SC-I, n = 81; LS-I, n = 64) who underwent HR-VWI were included in this study. The degree of MCA stenosis and the characteristics of MCA plaque (presence, eccentricity, location, extent, T2-high signal intensity [T2-HSI], and plaque enhancement) were analyzed, and compared between SC-I and LS-I, using Fisher's exact test. RESULTS: Stenosis was more severe in SC-I than in LS-I (p = 0.040). MCA plaque was more frequent in SC-I than in LS-I (p = 0.028), having larger plaque extent (p = 0.001), more T2-HSI (p = 0.001), and more plaque enhancement (p = 0.002). The eccentricity and location of the plaque showed no significant difference between the two groups. CONCLUSION: Both SC-I and LS-I have similar HR-VWI findings of the MCA plaque, but SC-I had more frequent, larger plaques with greater T2-HSI and enhancement. This suggests that HR-VWI may have a promising role in assisting the differentiation of underlying pathophysiological mechanism between SC-I and LS-I.
Cerebral Infarction* ; Constriction, Pathologic ; Ethics Committees, Research ; Humans ; Infarction ; Informed Consent ; Magnetic Resonance Imaging* ; Middle Cerebral Artery* ; Retrospective Studies ; Stroke

OBJECTIVE: Lister's tubercle is used as a standard anatomical landmark in hand surgery and arthroscopy procedures. In this study, we aimed to evaluate and propose a classification for anatomical variants of Lister's tubercle. MATERIALS AND METHODS: Between September 2011 and July 2014, 360 MRI examinations for wrists performed using 1.5T scanners in a single institution were retrospectively evaluated. The prevalence of anatomical variants of Lister's tubercle based on the heights and morphology of its radial and ulnar peaks was assessed. These were classified into three distinct types: radial peak larger than ulnar peak (Type 1), similar radial and ulnar peaks (Type 2) and ulnar peak larger than radial peak (Type 3). Each type was further divided into 2 subtypes (A and B) based on the morphology of the peaks. RESULTS: The proportions of Type 1, Type 2, and Type 3 variants in the study population were 69.2, 21.4, and 9.5%, respectively. For the subtypes, the Type 1A variant was the most common (41.4%) and conformed to the classical appearance of Lister's tubercle; whereas, Type 3A and 3B variants were rare configurations (6.4% and 3.1%, respectively) wherein the extensor pollicis longus tendon coursed along the radial aspect of Lister's tubercle. CONCLUSION: Anatomical variations of Lister's tubercle have potential clinical implications for certain pathological conditions and pre-procedural planning. The proposed classification system facilitates a better understanding of these anatomical variations and easier identification of at-risk and rare variants.
Arthroscopy ; Classification* ; Hand ; Magnetic Resonance Imaging* ; Prevalence ; Retrospective Studies ; Tendons ; Wrist