Dual-Energy CT for Pulmonary Embolism: Current and Evolving Clinical Applications

Pulmonary embolism (PE) is a potentially fatal disease if the diagnosis or treatment is delayed. Currently, multidetector computed tomography (MDCT) is considered the standard imaging method for diagnosing PE. Dual-energy CT (DECT) has the advantages of MDCT and can provide functional information for patients with PE. The aim of this review is to present the potential clinical applications of DECT in PE, focusing on the diagnosis and risk stratification of PE.

Dual-Energy CT for Pulmonary Embolism: Current and Evolving Clinical Applications

Pulmonary embolism (PE) is a potentially fatal disease if the diagnosis or treatment is delayed. Currently, multidetector computed tomography (MDCT) is considered the standard imaging method for diagnosing PE. Dual-energy CT (DECT) has the advantages of MDCT and can provide functional information for patients with PE. The aim of this review is to present the potential clinical applications of DECT in PE, focusing on the diagnosis and risk stratification of PE.

Cohort Profile: Firefighter Research on the Enhancement of Safety and Health (FRESH), a Prospective Cohort Study on Korean Firefighters

40 years or new hires with less than 1 year of service.

Prognostic Value of Dual-Energy CT-Based IodineQuantification versus Conventional CT in AcutePulmonary Embolism: A Propensity-Match Analysis

Objective@#The present study aimed to investigate whether quantitative dual-energy computed tomography (DECT) parametersoffer an incremental risk stratification benefit over the CT ventricular diameter ratio in patients with acute pulmonary embolism(PE) by using propensity score analysis. @*Materials and Methods@#This study was conducted on 480 patients with acute PE who underwent CT pulmonary angiography(CTPA) or DECT pulmonary angiography (DE CT-PA). This propensity-matched study population included 240 patients with acutePE each in the CTPA and DECT groups. Altogether, 260 (54.1%) patients were men, and the mean age was 64.9 years (64.9 ±13.5 years). The primary endpoint was all-cause death within 30 days. The Cox proportional hazards regression model was usedto identify associations between CT parameters and outcomes and to identify potential predictors. Concordance (C) statisticswere used to compare the prognoses between the two groups. @*Results@#In both CTPA and DECT groups, right to left ventricle diameter ratio ≥ 1 was associated with an increased risk of allcausedeath within 30 days (hazard ratio: 3.707, p< 0.001 and 5.573, p< 0.001, respectively). However, C-statisticsshowed no statistically significant difference between the CTPA and DECT groups for predicting death within 30 days(C-statistics: 0.759 vs. 0.819, p= 0.117). @*Conclusion@#Quantitative measurement of lung perfusion defect volume by DECT had no added benefit over CT ventriculardiameter ratio for predicting all-cause death within 30 days.

Guidelines for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging (KOSCI) - Part 3: Perfusion, Delayed Enhancement, and T1- and T2 Mapping

This document is the third part of the guidelines for the interpretation and post-processing of cardiac magnetic resonance (CMR) studies. These consensus recommendations have been developed by a Consensus Committee of the Korean Society of Cardiovascular Imaging (KOSCI) to standardize the requirements for image interpretation and post-processing of CMR. This third part of the recommendations describes tissue characterization modules, including perfusion, late gadolinium enhancement, and T1- and T2 mapping. Additionally, this document provides guidance for visual and quantitative assessment, consisting of “What-to-See,” “How-To,” and common pitfalls for the analysis of each module. The Consensus Committee hopes that this document will contribute to the standardization of image interpretation and post-processing of CMR studies.

Guidelines for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging—Part 3: Perfusion, Delayed Enhancement, and T1- and T2 Mapping

This document is the third part of the guidelines for the protocol, the interpretation and post-processing of cardiac magnetic resonance (CMR) studies. These consensus recommendations have been developed by the Consensus Committee of the Korean Society of Cardiovascular Imaging to standardize the requirements for image interpretation and post-processing of CMR. This third part of the recommendations describes tissue characterization modules, including perfusion, late gadolinium enhancement, and T1- and T2 mapping. Additionally, this document provides guidance for visual and quantitative assessment consisting of “What-to-See,” “How-To,” and common pitfalls for the analysis of each module. The Consensus Committee hopes that this document will contribute to the standardization of image interpretation and post-processing of CMR studies.

Guidelines for Cardiovascular Magnetic Resonance Imaging from Korean Society of Cardiovascular Imaging (KOSCI) - Part 1: Standardized Protocol

Cardiac magnetic resonance (CMR) imaging is widely used in many areas of cardiovascular disease assessment. This is a practical, standard CMR protocol for beginners that is designed to be easy to follow and implement. This protocol guideline is based on previously reported CMR guidelines and includes sequence terminology used by vendors, essential MR physics, imaging planes, field strength considerations, MRI-conditional devices, drugs for stress tests, various CMR modules, and disease/symptom-based protocols based on a survey of cardiologists and various appropriate-use criteria. It will be of considerable help in planning and implementing tests. In addressing CMR usage and creating this protocol guideline, we particularly tried to include useful tips to overcome various practical issues and improve CMR imaging. We hope that this document will continue to standardize and simplify a patient-based approach to clinical CMR and contribute to the promotion of public health.

Guidelines for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging (KOSCI) - Part 2: Interpretation of Cine, Flow, and Angiography Data

Cardiovascular magnetic resonance imaging (CMR) is expected to be increasingly used in Korea due to technology advances and the expanded national insurance coverage of these tests. For improved patient care, it is crucial not only that CMR images are properly acquired but that they are accurately interpreted by well-trained personnel. In response to the increased demand for CMR, the Korean Society of Cardiovascular Imaging (KOSCI) has issued interpretation guidelines in conjunction with the Korean Society of Radiology (KSR). KOSCI has also created a formal Committee on CMR Guidelines to write updated practices. The members of this Committee review previously published interpretation guidelines and discuss the patterns of CMR use in Korea.

Erratum: Analysis of Complications of Percutaneous Transthoracic Needle Biopsy Using CT-Guidance Modalities In a Multicenter Cohort of 10568 Biopsies

On page 323, the grant number was incorrectly numbered as HI15C1234. The correct number is HI15C3390.

Analysis of Complications of Percutaneous Transthoracic Needle Biopsy Using CT-Guidance Modalities In a Multicenter Cohort of 10568 Biopsies

OBJECTIVE: To analyze the complications of percutaneous transthoracic needle biopsy using CT-based imaging modalities for needle guidance in comparison with fluoroscopy in a large retrospective cohort. MATERIALS AND METHODS: This study was approved by multiple Institutional Review Boards and the requirement for informed consent was waived. We retrospectively included 10568 biopsies from eight referral hospitals from 2010 through 2014. In univariate and multivariate logistic analyses, 3 CT-based guidance modalities (CT, CT fluoroscopy, and cone-beam CT) were compared with fluoroscopy in terms of the risk of pneumothorax, pneumothorax requiring chest tube insertion, and hemoptysis, with adjustment for other risk factors. RESULTS: Pneumothorax occurred in 2298 of the 10568 biopsies (21.7%). Tube insertion was required after 316 biopsies (3.0%), and hemoptysis occurred in 550 cases (5.2%). In the multivariate analysis, pneumothorax was more frequently detected with CT {odds ratio (OR), 2.752 (95% confidence interval [CI], 2.325–3.258), p < 0.001}, CT fluoroscopy (OR, 1.440 [95% CI, 1.176–1.762], p < 0.001), and cone-beam CT (OR, 2.906 [95% CI, 2.235–3.779], p < 0.001), but no significant relationship was found for pneumothorax requiring chest tube insertion (p = 0.497, p = 0.222, and p = 0.216, respectively). The incidence of hemoptysis was significantly lower under CT (OR, 0.348 [95% CI, 0.247–0.491], p < 0.001), CT fluoroscopy (OR, 0.594 [95% CI, 0.419–0.843], p = 0.004), and cone-beam CT (OR, 0.479 [95% CI, 0.317–0.724], p < 0.001) guidance. CONCLUSION: Hemoptysis occurred less frequently with CT-based guidance modalities in comparison with fluoroscopy. Although pneumothorax requiring chest tube insertion showed a similar incidence, pneumothorax was more frequently detected using CT-based guidance modalities.

Guideline for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging—Part 1: Standardized Protocol

Cardiac magnetic resonance (CMR) imaging is widely used in many areas of cardiovascular disease assessment. This is a practical, standard CMR protocol for beginners that is designed to be easy to follow and implement. This protocol guideline is based on previously reported CMR guidelines and includes sequence terminology used by vendors, essential MR physics, imaging planes, field strength considerations, MRI-conditional devices, drugs for stress tests, various CMR modules, and disease/symptom-based protocols based on a survey of cardiologists and various appropriate-use criteria. It will be of considerable help in planning and implementing tests. In addressing CMR usage and creating this protocol guideline, we particularly tried to include useful tips to overcome various practical issues and improve CMR imaging. We hope that this document will continue to standardize and simplify a patient-based approach to clinical CMR and contribute to the promotion of public health.

Guidelines for Cardiovascular Magnetic Resonance Imaging from the Korean Society of Cardiovascular Imaging—Part 2: Interpretation of Cine, Flow, and Angiography Data

Cardiovascular magnetic resonance imaging (CMR) is expected to be increasingly used in Korea due to technological advances and the expanded national insurance coverage of CMR assessments. For improved patient care, proper acquisition of CMR images as well as their accurate interpretation by well-trained personnel are equally important. In response to the increased demand for CMR, the Korean Society of Cardiovascular Imaging (KOSCI) has issued interpretation guidelines in conjunction with the Korean Society of Radiology. KOSCI has also created a formal Committee on CMR guidelines to create updated practices. The members of this committee review previously published interpretation guidelines and discuss the patterns of CMR use in Korea.

Myocardial T1 and T2 Mapping: Techniques and Clinical Applications

Cardiac magnetic resonance (CMR) imaging is widely used in various medical fields related to cardiovascular diseases. Rapid technological innovations in magnetic resonance imaging in recent times have resulted in the development of new techniques for CMR imaging. T1 and T2 image mapping sequences enable the direct quantification of T1, T2, and extracellular volume fraction (ECV) values of the myocardium, leading to the progressive integration of these sequences into routine CMR settings. Currently, T1, T2, and ECV values are being recognized as not only robust biomarkers for diagnosis of cardiomyopathies, but also predictive factors for treatment monitoring and prognosis. In this study, we have reviewed various T1 and T2 mapping sequence techniques and their clinical applications.

Predictors of False-Negative Results from Percutaneous Transthoracic Fine-Needle Aspiration Biopsy: An Observational Study from a Retrospective Cohort

PURPOSE: We investigated factors predictive of false-negative pulmonary lesions with nonspecific benign cytology results on percutaneous transthoracic fine-needle aspiration biopsy (FNAB). MATERIALS AND METHODS: We included 222 pulmonary lesions that had a nonspecific benign result from percutaneous transthoracic FNAB between March 2005 and December 2012, and were confirmed by subsequent pathologic results or adequate clinical follow up over at least 2 years. Clinical, imaging, and biopsy procedure-related findings were compared between lesions with a final diagnosis of malignancy (false-negative) and lesions with a benign diagnosis (true-negative). Multivariate logistic regression analysis was performed to identify significant predictors of false-negatives. RESULTS: Of 222 lesions, 115 lesions were proved to be false-negatives, and 107 were true-negatives. Compared with the true-negatives, false-negative lesions showed significantly older age (p=0.037), higher maximum standardized uptake value (SUVmax) on positron emission tomography (p=0.001), larger lesion size (p=0.007), and lesion characteristics of a subsolid nodule (p=0.007). On multivariate logistic regression analysis, SUVmax, lesion size, and lesion characteristics were significant predictors of false-negative results. CONCLUSION: Among the clinical, radiologic, and procedure-related factors analyzed, high SUVmax, large lesion size, and subsolid lesions were useful for predicting malignancy in pulmonary lesions with nonspecific benign cytology results on FNAB.

Measurement of Opening and Closing Angles of Aortic Valve Prostheses In Vivo Using Dual-Source Computed Tomography: Comparison with Those of Manufacturers' in 10 Different Types

OBJECTIVE: The aims of this study were to compare opening and closing angles of normally functioning mechanical aortic valves measured on dual-source computed tomography (CT) with the manufacturers' values and to compare CT-measured opening angles according to valve function. MATERIALS AND METHODS: A total of 140 patients with 10 different types of mechanical aortic valves, who underwent dual-source cardiac CT, were included. Opening and closing angles were measured on CT images. Agreement between angles in normally functioning valves and the manufacturer values was assessed using the interclass coefficient and the Bland-Altman method. CT-measured opening angles were compared between normal functioning valves and suspected dysfunctioning valves. RESULTS: The CT-measured opening angles of normally functioning valves and manufacturers' values showed excellent agreement for seven valve types (intraclass coefficient [ICC], 0.977; 95% confidence interval [CI], 0.962-0.987). The mean differences in opening angles between the CT measurements and the manufacturers' values were 1.2degrees in seven types of valves, 11.0degrees in On-X valves, and 15.5degrees in ATS valves. The manufacturers' closing angles and those measured by CT showed excellent agreement for all valve types (ICC, 0.953; 95% CI, 0.920-0.972). Among valves with suspected dysfunction, those with limitation of motion (LOM) and an increased pressure gradient (PG) had smaller opening angles than those with LOM only (p < 0.05). CONCLUSION: Dual-source cardiac CT accurately measures opening and closing angles in most types of mechanical aortic valves, compared with the manufacturers' values. Opening angles on CT differ according to the type of valve dysfunction and a decreased opening angle may suggest an elevated PG.

Bullous Dermatomyositis Associated with Squamous Cell Carcinoma of the Lung / 대한피부과학회지

Dermatomyositis (DM) is a rare progressive autoimmune disease characterized by inflammatory myopathy, which classically manifests as several characteristic cutaneous features, including Gottron's papules, periorbital heliotrope rashes, poikiloderma, and reticular telangiectasis. Vesicle or bulla formation in dermatomyositis was first reported in 1903, and a few similar cases have been reported since then. Bullous DM has been associated with internal malignancies. We herein describe a case of bullous DM with squamous cell carcinoma of the lung in a 69-year old man.

A Case of Influenza-associated Encephalopathy

Influenza-associated encephalopathy is regarded as one of the major neurologic disease entities along with those of Reye syndrome, acute necrotizing encephalopathy, and myelitis which are known to be related to influenza virus, mostly type A. And it is being actively researched in Japan as it has caused a tremendous increase in the number of deaths from 1997 to 2002, but it has not been yet reported in the Korean pediatric medical community. It attacks those previously healthy children, who have not been vaccinated. Patients start with such symptoms as fever and common respiratory problems, but within 24 to 48 hours they suffer from seizures with acute mental deterioration, become worse, and suffer multiple organ failures including marked elevated transaminase levels as well as coagulopathy. It induces deaths in a couple of days after the symptoms appear or remains a serious neurologic sequelae. Confirmative diagnosis is used to demonstrate influenza viral infection. We report here a 37 month aged boy who was admitted to our hospital during the last influenza season under the diagnosis of influenza associated encephalopathy on the basis of serologic testing by hemagglutinin inhibition(HI). This is the first report confirmed by increased antibody titer of the influenza A virus in Korea.

The Clinical Features of Acute Disseminated Encephalomyelitis in Children / 대한소아신경학회지

PURPOSE: Acute disseminated encephalomyelitis(ADEM) is an immunologically mediated demyelinating disease of the central nervous system. We investigated the clinical features and outcomes of children with ADEM presenting with different neurologic symptoms and clinical courses. METHODS: Fifteen cases(male 10 and female 5) of ADEM who were diagnosed in the department of pediatrics, Samsung Medical Center from July 1997 to April 2001 were reviewed. RESULTS: The ages at initial presentations were from 1 year 5 months to 14 year 8 months. The presence of preceding events was present in all patients. The most common presenting symptom was seizure(60%), followed by altered consciousness(40%), ataxia(33 %), cranial nerve palsy, headache, quadriparesis, visual disturbance, and tremor. Brain magnetic resonance imaging showed relatively symmetrical, multifocal hyperintense lesions on T2-weighted image. One out of 4 brain CT showed an abnormal finding and remaining 3 cases showed abnormal findings in MRI only. Two patients had normal MRI findings at the initial phase of the illness but later revealed MRI findings compatible with ADEM. Thirteen patients were managed on high dose methylprednisolone therapy and/or intravenous immunoglobulin. After treatments, all patients revealed rapid clinical recovery. Relapse occurred in four patients(26%) 3 weeks to 1 year 6 months after developing their first illness. Among them, two patients were diagnosed as multiple sclerosis later. CONCLUSION: We experienced 15 children with the initial diagnosis of ADEM. Even though immunosuppressive drugs were effective to eliminate their presenting symptoms in most patients, there was 26% of relapse rate with 2 patients with later diagnosis of multiple sclerosis during long-term follow-up suggesting heterogeneity existed with regard to etiology and clinical courses of ADEM.

Mobilization and Collection of the Peripheral Blood Stem Cell from Normal Bone Marrow by G-CSF Alone / 대한소아혈액종양학회지

PURPOSE: Peripheral blood stem cells (PBSC) can be mobilized by use of G-CSF alone from normal bone marrow. In this study, feasibility of mobilization, collection, and hematologic recovery after transplantion were evaluated. METHPDS: From normal undamaged bone marrow of normal PBSC donors and patients with high risk brain tumor who had no experience of chemotherapy or radiotherapy, PBSC was mobilized by use of G-CSF alone. Ten ug/kg/day of G-CSF was injected subcutaneously and leukaphereses were done on the fourth and fifth day of G-CSF injection. Nucleated cells (NC), mononuclear cells (MNC), CD34+ cells and colony forming cells (CFC) were counted. Hematologic recovery was evaluated in 4 autologous transplantations and 6 allogeneic transplantations, 4 of which were done after T cell depletion. RESULTS: Twenty four leukaphereses were done in 6 normal donors and 6 patients with high risk brain tumor. Median 603.3 (342.6~834.5) mL/kg of blood was processed for median 447 (392~549) minutes. Collected cells were as follows; NC: 11.88 (3.11~25.89)x108/kg of donor, MNC: 8.66 (2.61~12.84)x10(8)/kg of donor, CD34+ cells: 7.05 (2.95~11.73)x10(6)/kg of donor, CFC: 25.38 (3.62~35.27)x10(5)/kg of donor, respectively. In allogeneic transplantation, time to reach absolute neutrophil count (ANC)> 500/uL, 1,000/ uL and platelet count> 20,000/uL, 50,000/uL were 10 (9~15) days, 11 (9~16) days, 11 (8~30) days, and 32 (19~156) days, respectively. In autologous transplantation, time to reach ANC> 500/uL, 1,000/uL and platelet count> 20,000/uL, 50,000/uL were 9.5 (9~11) days, 10.0 (9~11) days, 10.5 (9~13) days, and 14.5 (13~17) days, respectively. CONCLUSION: Sufficient number of undamaged PBSC was collected from normal bone marrow by use of G-CSF alone. Hematologic recovery after transplantaion was more rapid than allogeneic bone marrow transplantation or autologous PBSCT which was done with cells collected after chemotherapy and/or radiotherapy.

Two Cases of Actinic Granuloma / 대한피부과학회지

Actinic granuloma is a specific disease entity characterized by clinical lesions indistinguishable from granuloma annulare, but occuring on solar damageci skin. Ilistologically, elastic tissues are destroyed by the granulomatous process in actinic granuloma, but not, in granuloma anriulare. We report two cases of actinic granuloma with each diagnosed as a giant cell and sarcoirlal variant of the disease. Interestingly, one case developed on the non sun-exposed skin and anothr case related to the history of an insect bite.