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1.
Sci Rep ; 6: 21136, 2016 02 17.
Article in English | MEDLINE | ID: mdl-26883174

ABSTRACT

Anisotropic graphene domains are of significant interest since the electronic properties of pristine graphene strongly depend on its size, shape, and edge structures. In this work, considering that the growth of graphene domains is governable by the dynamics of the graphene-substrate interface during growth, we investigated the shape and defects of graphene domains grown on copper lattices with different indices by chemical vapor deposition of methane at either low pressure or atmospheric pressure. Computational modeling identified that the crystallographic orientation of copper strongly influences the shape of the graphene at low pressure, yet does not play a critical role at atmospheric pressure. Moreover, the defects that have been previously observed in the center of four-lobed graphene domains grown under low pressure conditions were demonstrated for the first time to be caused by a lattice mismatch between graphene and the copper substrate.

2.
PLoS One ; 9(4): e95887, 2014.
Article in English | MEDLINE | ID: mdl-24755938

ABSTRACT

OBJECTIVE: Aortic unfolding occurs with aging and reflects proximal aortic dilation, aortic arch widening, and decreased curvature. This study 1) evaluated the relationship between aortic unfolding measured using non-contrast cardiac-gated computed tomography (CT) and age, 2) assessed factors influencing aortic unfolding, and 3) determined the association of this measurement with coronary artery calcium (CAC) score. METHODS: We reviewed the charts of 219 subjects (142 men, 77 women; mean age 54.2±9.3 years) who underwent coronary artery calcium scanning during routine health screening from December 2010 to May 2011. Multivariate regression analysis according to cardiovascular risk factors was performed. We also analyzed the relationship between aortic unfolding measurements and CAC score using stepwise multiple linear regression. RESULTS: Mean aortic unfolding was 103.7±13.9 mm (men, 106.5±13.5 mm; women, 98.4±12.9 mm). Age, body surface area, and hypertension were exclusively associated with aortic unfolding. The association between aortic unfolding and CAC score was significant after adjustment for age and gender (ß = 1.89, p = 0.017) and for Framingham risk score (ß = 2.83, p<0.001). CONCLUSIONS: Aortic unfolding defined by measuring aortic width was a reproducible and practical method with non-contrast cardiac CT and associated with age, body surface area, and hypertension. CAC score, a well-established surrogate marker of cardiovascular disease, is positively associated with aortic unfolding. Further study to evaluate aortic unfolding as a potential predictor of cardiovascular risk is warranted.


Subject(s)
Aortic Diseases/diagnostic imaging , Coronary Vessels/pathology , Vascular Calcification/diagnostic imaging , Adult , Age Distribution , Age Factors , Aged , Coronary Vessels/diagnostic imaging , Female , Humans , Male , Middle Aged , Risk , Sex Distribution , Tomography, X-Ray Computed
3.
J Nanosci Nanotechnol ; 14(12): 9169-73, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25971031

ABSTRACT

We report that graphene flakes and films which were synthesized by copper-catalyzed atmospheric pressure chemical vapor deposition (APCVD) method using a mixture of Ar, H2, and CH4 gases. It was found that variations in the reaction parameters, such as reaction temperature, annealing time, and growth time, influenced the domain size of as-grown graphene. Besides, the reaction parameters influenced the number of layers, degree of defects and uniformity of the graphene films. The increase in growth temperature and annealing time tends to accelerate the graphene growth rate and increase the diffusion length, respectively, thereby increasing the average size of graphene domains. In addition, we confirmed that the number of pinholes reduced with increase in the growth time. Micro-Raman analysis of the as-grown graphene films confirmed that the continuous graphene monolayer film with low defects and high uniformity could be obtained with prolonged reaction time, under the appropriate annealing time and growth temperature.

4.
Magn Reson Med ; 69(6): 1645-9, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22760954

ABSTRACT

In this study, we investigated the effects of changes in pulmonary blood flow on oxygen-enhanced lung magnetic resonance imaging. Increased pulmonary blood flow was produced by intravenous infusion of sildenafil (0.2 mg/kg) in 10 New Zealand white rabbits. Decreased pulmonary blood flow was produced by single subcutaneous injection of monocrotaline (60 mg/kg). A velocity-encoded cine magnetic resonance imaging for pulmonary blood flow and an oxygen-enhanced lung magnetic resonance imaging were performed at baseline, during sildenafil infusion, and after monocrotaline injection. We compared the baseline data to those obtained during sildenafil infusion and after monocrotaline injection for pulmonary blood flow changes and signal intensity enhancement ratios of oxygen-enhanced lung magnetic resonance imaging. Wilcoxon's signed rank test was used for statistical analysis. There was a significant difference between pulmonary blood flow at baseline (418.6±108.9 mL/min) and after sildenafil (491.9±118.0 mL/min; P=0.005) or between pulmonary blood flow at baseline and after monocrotaline administration (356.3±85.8 mL/min; P=0.017). However, there was no significant difference between the signal intensity enhancement ratios at baseline (23.8±11.4%) and after sildenafil (24.0±7.9%; P=0.953) or the signal intensity enhancement ratios at baseline and after monocrotaline administration (22.7±10.3%; P=0.374). Changes in pulmonary blood flow had little effect on the signal intensity enhancement ratio of oxygen-enhanced lung magnetic resonance imaging.


Subject(s)
Lung/anatomy & histology , Lung/physiology , Magnetic Resonance Angiography/methods , Magnetic Resonance Imaging/methods , Oxygen/blood , Pulmonary Circulation/physiology , Administration, Inhalation , Animals , Blood Flow Velocity/physiology , Contrast Media/administration & dosage , Male , Oxygen/administration & dosage , Rabbits , Reproducibility of Results , Sensitivity and Specificity
5.
Cancer Cytopathol ; 121(4): 214-22, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23225527

ABSTRACT

BACKGROUND: The purpose of this study was to assess whether analyses of tumor markers in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) for the diagnosis of ground-glass opacity (GGO) pulmonary lesions. METHODS: Forty-two patients were prospectively enrolled for CT-guided NAB. Levels of cytokeratin 19 fragments (CYFRA 21-1) and carcinoembryonic antigen (CEA) from serum and cytological fluid were measured. The cutoff values of 3.3 ng/mL for CYFRA 21-1 and 5.0 ng/mL for CEA (threshold A) or thresholds by adding 2 standard deviations to the mean levels of markers found in patients without malignancy (threshold B) were used to identify malignancy. The sensitivity and area under the curve (AUC) of NAB alone were compared with those of NAB combined with serum or cytological tumor markers. RESULTS: Among the 42 patients, 30 (71.4%) had malignant and 12 (28.6%) had benign lesions. For NAB alone, the sensitivity, specificity, and AUC for diagnosing GGO were 70.0%, 100%, and 0.850, respectively. The sensitivity and AUC increased significantly for NAB with cytological CYFRA 21-1 compared with NAB alone, using both thresholds (threshold A: 86.7%, P=.026 and .933, P=.016; threshold B: 93.3%, P=.008 and .925, P=.046). CONCLUSIONS: Cytological fluid measurements of CYFRA 21-1 can improve the diagnostic performance of CT-guided NAB for GGO pulmonary lesions.


Subject(s)
Antigens, Neoplasm/metabolism , Biomarkers, Tumor/metabolism , Keratin-19/metabolism , Lung Diseases/diagnosis , Lung/pathology , Tomography, X-Ray Computed , Adult , Aged , Biopsy, Needle , Carcinoembryonic Antigen/metabolism , Cytodiagnosis , Female , Humans , Image-Guided Biopsy , Lung/metabolism , Lung Diseases/metabolism , Male , Middle Aged , Prognosis , Prospective Studies , ROC Curve , Sensitivity and Specificity
6.
Int J Cardiovasc Imaging ; 28 Suppl 2: 101-7, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23099512

ABSTRACT

To determine the feasibility of dual-source coronary CT angiography (CTA) using a prospectively electrocardiogram (ECG)-triggered axial mode to target end-systole in patients with high heart rates (HR) as compared with the retrospective mode. One hundred fifty consecutive patients with regular HR > 75 bpm who underwent coronary CTA were enrolled; 75 patients underwent prospectively ECG-triggered coronary CTA targeting only end-systole (Prospective Axial Group) and 75 patients underwent retrospectively ECG-gated coronary CTA (Retrospective Helical Group). The image quality of multiple coronary artery segments was evaluated and radiation doses were recorded. The diagnostic performance of coronary CTA was compared to the reference standard of invasive coronary angiography in 52 patients (35 %) (28 patients in Prospective Axial Group and 24 patients in Retrospective Helical Group). Image quality was not significantly different between the 2 groups (P = 0.784). In subgroup analysis, segment-based sensitivity, specificity, and positive and negative predictive values of coronary CTA were 98, 96, 88 and 99 %, respectively, in the Prospective Axial Group and were 97, 95, 82, and 99 %, respectively, in the Retrospective Helical Group. Mean radiation dose was significantly lower for the Prospective Axial Group than for the Retrospective Helical Group (2.9 ± 1.4 vs. 7.4 ± 3.3 mSv; P < 0.0001). Dual source coronary CTA with a prospective ECG-triggered axial mode targeting end-systole is feasible in patients with regular high HRs for evaluation of coronary artery disease. It provides comparable image quality and diagnostic value with substantially lower radiation exposure as compared to the retrospective ECG-gated helical technique.


Subject(s)
Cardiac-Gated Imaging Techniques/methods , Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Electrocardiography , Heart Rate , Tomography, Spiral Computed , Aged , Cardiac-Gated Imaging Techniques/standards , Chi-Square Distribution , Coronary Angiography/standards , Coronary Artery Disease/physiopathology , Feasibility Studies , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Radiation Dosage , Reference Standards , Sensitivity and Specificity , Systole , Tomography, Spiral Computed/standards
7.
BMC Cancer ; 12: 392, 2012 Sep 07.
Article in English | MEDLINE | ID: mdl-22954172

ABSTRACT

BACKGROUND: Cytological fluid from a needle aspiration biopsy (NAB) is obtained directly from tumor tissue, therefore many biomarker candidates will be present in high concentrations. The aim of this study was to prospectively assess and validate the tumor markers CYFRA 21-1, CEA, and SCC in cytological fluid obtained from NAB samples to determine if they improved the performance of NAB for diagnosing non-small cell lung cancer (NSCLC). METHODS: A total of 194 patients (M:F = 128:66, mean age 63.7 years) with suspected malignant pulmonary lesions were prospectively enrolled and underwent percutaneous NAB. Levels of CYFRA 21-1, CEA, and SCC were measured by immunoassay in serum and cytological fluid obtained during aspiration biopsy. Cut-off values to determined malignancy were 3.3 ng/mL in serum and 15.7 ng/mL in cytological fluid for CYFRA 21-1, 5 ng/mL and 0.6 ng/mL for CEA, and 2 ng/mL and 0.86 ng/mL for SCC. RESULTS: Of 194 patients, 139 patients (71.6%) had NSCLC and 55 (28.4%) had benign lesions. Sensitivity increased significantly for NAB combined with cytological tumor markers compared with NAB alone (CYFRA 21-1: 95% versus 83.5%, p < 0.001, CEA: 92.1% versus 83.5%, p = 0.002, SCC: 91.4% versus 83.5%, p = 0.003). Accuracy improved significantly for NAB combined with cytological CYFRA 21-1 compared with NAB alone (95.9% versus 88.1%, p < 0.001). The area under curve (AUC) of NAB with cytological CYFRA 21-1 was significantly larger than for NAB alone (0.966 versus 0.917, p = 0.009). CONCLUSION: Of the tested tumor markers, cytological fluid measurements of CYFRA 21-1 improved the diagnostic performance of NAB for NSCLC.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/diagnosis , Extracellular Fluid/metabolism , Lung Neoplasms/diagnosis , Aged , Antigens, Neoplasm/blood , Antigens, Neoplasm/metabolism , Biomarkers, Tumor/blood , Biopsy, Needle , Carcinoembryonic Antigen/blood , Carcinoembryonic Antigen/metabolism , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Keratin-19/blood , Keratin-19/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , ROC Curve , Reproducibility of Results , Serpins/blood , Serpins/metabolism
8.
Korean J Fam Med ; 33(4): 237-42, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22916326

ABSTRACT

BACKGROUND: Improvement of additional immunization rate is indicated as an important factor for effective immunization of diseases. In this study, the relationship between retention of mother and child health handbook and additional immunization rate of Japanese encephalitis and tetanus was examined. METHODS: A survey via questionnaire was performed against parents of students of middle schools in Gwangmyeong-si, Gyeonggi-do, and elementary schools in Seoul. Among 350 copies of the questionnaire delivered via post mail, 261 copies were collected and used in the analysis. The questionnaire included general features of subjects and their children, retention of the mother and child health handbook, and recognition of additional immunization of the Japanese encephalitis and tetanus vaccine. RESULTS: It was found that 80.8% of subjects answered affirmative to retaining the mother and child health handbook, and the group retaining the handbook had higher recognition rate of the need for additional immunization than the group that did not, for the Japanese encephalitis vaccine (83.2% vs. 51.2%, P < 0.001) and for the tetanus vaccine (66.5% vs. 31.7%, P < 0.001). Although the group retaining the handbook had a significantly higher additional immunization rate of the tetanus vaccine of 48.6% vs. 17.1% (P = 0.001), the immunization rate of the Japanese encephalitis vaccine did not show a significant difference (P = 0.231). The group recognizing the need for additional immunization of the Japanese encephalitis and tetanus vaccine had a significantly higher additional immunization rate than the counterpart (P < 0.001). CONCLUSION: It was considered that retention of the mother and child health handbook was related to recognition and execution of additional immunizations.

9.
J Cardiovasc Comput Tomogr ; 6(3): 184-90, 2012.
Article in English | MEDLINE | ID: mdl-22551594

ABSTRACT

BACKGROUND: The use of Automatic Tube Potential Selection with Tube Current Modulation (APSCM) may lower radiation dose, but it is unknown whether image quality is maintained. OBJECTIVE: The aim of this study was to evaluate the radiation dose and image quality of APSCM application compared with conventional body mass index (BMI)-based examination protocol for coronary computed tomography angiography (CTA). METHODS: Consecutive patients (n = 487) were retrospectively enrolled: 239 patients who underwent coronary CTA with APSCM (APSCM group) and 248 patients who underwent coronary CTA with a BMI-based tube potential (in kV) and tube current-time product (in mAs) protocol (BMI-based group). Comparison of quantitative and qualitative image quality and radiation dose was performed. RESULTS: The use of APSCM found significant reduction in radiation dose compared with the BMI-based protocol, with a significantly more frequent use of 80 kV (P < 0.0001). Diagnostic image quality was maintained, with no significant difference between the 2 groups (P = 0.887). CONCLUSION: The use of APSCM for coronary CTA significantly reduced radiation dose while maintaining image quality; therefore, it is feasible in daily practice which covers patients with various BMI values.


Subject(s)
Coronary Angiography/methods , Image Enhancement/methods , Radiation Dosage , Radiation Protection/methods , Radiographic Image Enhancement/methods , Software , Tomography, X-Ray Computed/methods , Algorithms , Body Mass Index , Humans , Reproducibility of Results , Sensitivity and Specificity , Software Validation
10.
Radiology ; 263(3): 688-95, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22495682

ABSTRACT

PURPOSE: To assess the diagnostic performance of dual-energy cardiac computed tomography (CT) in the detection of left atrial appendage (LAA) thrombi and differentiation between thrombus and circulatory stasis in patients with stroke, by using transesophageal echocardiography (TEE) as the reference standard. MATERIALS AND METHODS: The institutional review board approved this study, and patients provided informed consent. Thirty-two patients with stroke who had atrial fibrillation (AF) and either thrombus or the spontaneous echo contrast (SEC) echo pattern at TEE were prospectively enrolled. For the control group, 31 patients who were planning to undergo AF ablation and who had no abnormalities at TEE were enrolled. All patients underwent dual-energy cardiac CT that was not electrocardiographically gated. For quantitative analysis, iodine concentration was measured on CT images. The statistical significance of differences in mean iodine concentration between thrombus and SEC as measured at CT was assessed by using the Student t test. RESULTS: Among the 63 patients, a total of 13 thrombi and 19 instances of SEC were detected at TEE. Using TEE as the reference standard, the overall sensitivity, specificity, positive predictive value, and negative predictive value of dual-energy cardiac CT in the detection of thrombi and SEC in the LAA were 97% (95% confidence interval [CI]: 82%, 100%), 100% (95% CI: 86%, 100%), 100%, and 97%, respectively. At CT, the mean iodine concentration was 1.23 mg/mL ± 0.34 (standard deviation) for thrombus and 3.61 mg/mL ± 1.01 for SEC (P = .001). CONCLUSION: Dual-energy cardiac CT is a highly sensitive modality for detecting LAA thrombus and for differentiating thrombus from SEC in patients with stroke.


Subject(s)
Atrial Appendage/diagnostic imaging , Coronary Thrombosis/complications , Coronary Thrombosis/diagnostic imaging , Stroke/etiology , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Case-Control Studies , Chi-Square Distribution , Contrast Media , Coronary Circulation , Diagnosis, Differential , Echocardiography, Transesophageal , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , ROC Curve , Radiographic Image Interpretation, Computer-Assisted , Risk Factors , Sensitivity and Specificity , Triiodobenzoic Acids
11.
Eur Heart J Cardiovasc Imaging ; 13(9): 776-85, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22461571

ABSTRACT

AIMS: The clinical implication of a zero coronary calcium score (CCS) in patients with chest pain syndrome has been under debate. This study was undertaken to determine the meaning of a CCS of zero in a large sample of symptomatic patients referred for coronary computed tomographic (CT) angiography. METHODS AND RESULTS: We consecutively enrolled 2088 patients (age 58 ± 10 years, 1028 men) who had undergone 64-slice cardiac CT due to chest pain syndrome. A CCS of zero was detected in 1114 patients (471 men and 643 women). Of these 1114 patients, obstructive coronary artery disease (CAD) was found in a total of 48 patients (4.3%); 35 men (7.4%) and 13 women (2.0%). Among the zero CCS patients with obstructive CAD, men had a higher prevalence of both premature CAD (49 vs. 0%) and multivessel disease (20 vs. 8%) than women. During the follow-up period (1033 ± 136 days), early revascularization was done in 25 patients (2.2%, 18 men and 7 women) and there were 14 major adverse cardiac events (1.3%, 8 men and 7 women) among the zero CCS patients. CAD severity was a strong prognostic indicator in the zero CCS patients. CONCLUSION: A CCS of zero cannot be used by itself to exclude obstructive CAD in symptomatic patients referred for coronary CT angiography (CCTA). The prevalence of obstructive CAD and adverse cardiac events are not negligible in symptomatic patients with a CCS of zero, and CAD severity by CCTA is associated with higher rates of adverse cardiac event.


Subject(s)
Calcinosis/diagnostic imaging , Chest Pain/diagnostic imaging , Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Cardiac-Gated Imaging Techniques , Chi-Square Distribution , Contrast Media , Female , Humans , Iopamidol , Male , Middle Aged , Prevalence , Proportional Hazards Models , Retrospective Studies , Risk Assessment , Risk Factors
12.
Radiology ; 262(1): 101-8, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22056684

ABSTRACT

PURPOSE: To classify anomalous origins of the right coronary artery (RCA) from the left coronary sinus (AORL) with an interarterial course into two subtypes and to evaluate the clinical importance of each. MATERIALS AND METHODS: Institutional review board approval was obtained for this retrospective study, and informed consent was waived. Through a retrospective review of 22,925 consecutive cardiac computed tomographic (CT) scans, 124 cases of AORL with an interarterial course were identified. These anomalies were classified into two subtypes according to the location of the anomalous RCA ostium: high interarterial course (between the aorta and the pulmonary artery) and low interarterial course (between the aorta and the right ventricular outflow tract). The clinical records were evaluated, and differences in prevalence of typical angina and major adverse cardiac events (MACEs) between the subtypes were analyzed through the χ(2) contingency tables or Fisher exact test. RESULTS: After excluding patients with combined cardiac disease, 87 patients (51 [59%] men, 36 [41%] women; mean age, 56.0 years) were enrolled. Of the 87 patients, 53 had a high interarterial course and 34 had a low interarterial course. A significant difference in the prevalence of typical angina (high [43%] vs low [6%], P = .001) and MACE (high [28%] vs low [6%], P = .012) was observed between the two subtypes. For patients with a high interarterial course, the odds ratio for typical angina was 12.3 (95% confidence interval: 2.7, 56.6), and the odds ratio for MACE was 6.3 (95% confidence interval: 1.3, 29.7). CONCLUSION: The prevalence of typical angina and that of MACE were significantly higher in patients with a high interarterial course than in those with a low interarterial course.


Subject(s)
Coronary Vessel Anomalies/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Angina, Unstable/diagnostic imaging , Angina, Unstable/mortality , Biomarkers/analysis , Chi-Square Distribution , Contrast Media , Coronary Vessel Anomalies/classification , Coronary Vessel Anomalies/mortality , Death, Sudden, Cardiac/epidemiology , Electrocardiography , Female , Follow-Up Studies , Humans , Iopamidol , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/mortality , Retrospective Studies
13.
Int J Cardiovasc Imaging ; 28(2): 353-63, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21279690

ABSTRACT

The aim of this study was to compare delayed-phase computed tomography angiography (CTA) attenuation values with histopathology, in ability to differentiate between fibrous and lipid-rich plaques in an experimental rabbit model. Twelve atherosclerotic rabbits underwent CTA of the abdominal aorta. The scan protocol included early-phase scans (EP), delayed scans at 90 s after contrast injection (DP(90s)), delayed scans at 10 min after contrast injection (DP(10min)), and delayed scan with saline infusion (DP(Saline)). Plaque composition was analyzed by histopathology (% of lipid-rich, fibrous and macrophage areas) and CT attenuation values in Hounsfield units. Using histopathology as the reference standard (n = 119), the overall sensitivity, specificity and accuracy of 64-slice CTA for the detection of plaques was 59, 100 and 79% for the EP scans; 88, 100 and 94% for the DP(90s) scans; 81, 100 and 90% for the DP(10min) scans; and 53, 100 and 76% for the DP(Saline) scans. CT density measurements showed a substantial overlap between fibrous and lipid-rich plaques, and poor correlations with the percentage of macrophage areas in both fibrous and lipid-rich plaques (r = 0.408, and r = 0.333). In delayed-phase 64-slice CTA, DP(90s) images have the best diagnostic performance for the detection of aortic plaques.


Subject(s)
Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/pathology , Aortic Diseases/diagnosis , Aortography/methods , Atherosclerosis/diagnosis , Contrast Media , Plaque, Atherosclerotic/diagnosis , Tomography, X-Ray Computed , Animals , Aorta, Abdominal/chemistry , Aortic Diseases/diagnostic imaging , Aortic Diseases/metabolism , Aortic Diseases/pathology , Atherosclerosis/diagnostic imaging , Atherosclerosis/metabolism , Atherosclerosis/pathology , Disease Models, Animal , Fibrosis , Lipids/analysis , Macrophages/diagnostic imaging , Macrophages/pathology , Male , Plaque, Atherosclerotic/chemistry , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/pathology , Predictive Value of Tests , Rabbits , Reproducibility of Results , Sensitivity and Specificity
14.
Int J Cardiovasc Imaging ; 27 Suppl 1: 89-95, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22002687

ABSTRACT

The objectives of this study were to evaluate the diagnostic value of delayed-enhancement cardiovascular magnetic resonance (DE-CMR) imaging in differentiating cardiac tumors from thrombi in patients with suspected cardio-embolic stroke. Two radiologists blinded to the study protocol retrospectively evaluated MR images of 22 patients (12 men and 10 women; mean age 59.2 years) that had recently experienced a stroke and undergone CMR. Six cardiac tumors and 16 thrombi were confirmed on surgery or follow-up examinations. On DE-CMR, a tumor was defined as an intracardiac mass showing post-contrast enhancement, and a thrombus was defined as an intracardiac mass showing black signal intensity (SI) without post-contrast enhancement. The mean SI in regions of interest in the normal myocardium and cardiac mass were measured using cine-CMR and DE-CMR. Visual assessment of enhancement characteristics of cardiac masses on DE-CMR could accurately differentiate cardiac tumors from thrombi in all cases. On cine-CMR, the mean SI ratios for tumors and thrombi were 1.45 ± 0.45 (range, 1.12-2.16) and 1.39 ± 0.33 (range, 0.87-2.09), respectively (P = 0.745). On DE-CMR, the mean SI ratios for tumors and thrombi were 5.65 ± 2.96 (range, 2.98-9.92) and 1.06 ± 0.43 (range, 0.67-1.95), respectively (P < 0.001). DE-CMR is a non-invasive modality for detecting intra-cardiac mass can differentiate tumors from thrombi in cardio-embolic stroke patients.


Subject(s)
Contrast Media , Heart Neoplasms/pathology , Image Enhancement/methods , Magnetic Resonance Imaging/methods , Stroke/complications , Thrombosis/pathology , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Follow-Up Studies , Heart Neoplasms/complications , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging, Cine , Male , Middle Aged , Observer Variation , Reproducibility of Results , Retrospective Studies , Thrombosis/complications
15.
J Thorac Oncol ; 6(8): 1330-5, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21847061

ABSTRACT

PURPOSE: The aim of this study was to prospectively assess whether analysis of the tumor markers cytokeratin 19 fragments (CYFRA 21-1), carcinoembryonic antigen (CEA), and squamous cell carcinoma (SCC) antigen in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) in the diagnosis of non-small cell lung cancer (NSCLC). METHODS: A total of 100 patients (men:women = 41:59, mean age: 63 years) with suspected malignant pulmonary lesions were prospectively enrolled for CT-guided NAB procedures. Levels of CYFRA 21-1, CEA, and SCC in the cytological fluid were measured by immunoradiometric assays. The cutoff value for tumor markers was selected on the basis of best accuracy through receiver operating characteristic curves. The sensitivity and areas under the curve (AUC) of NAB alone were compared with those of NAB combined with cytological tumor markers (CYFRA 21-1, CEA, and SCC). RESULTS: Among 100 patients, 71 (71%) had NSCLC and 29 (29%) had benign lesions. The sensitivity, specificity, and accuracy for diagnosing NSCLC were 85.7%, 100%, and 89%, respectively, for NAB alone. The sensitivity increased significantly for NAB combined with a tumor marker compared with NAB alone (100% for CYFRA 21-1, 92.9% for CEA, and 94.2% for SCC; p = 0.001, p = 0.025, and p = 0.014, respectively). The AUC of NAB with CYFRA 21-1 was significantly larger than the AUC of NAB alone (p = 0.001). CONCLUSION: Evaluation of tumor markers CYFRA 21-1, CEA, and SCC in the cytological fluid can improve the diagnostic performance of CT-guided NAB for NSCLC. Of these markers, CYFRA 21-1 is the most useful cytological tumor marker.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/diagnosis , Lung Neoplasms/metabolism , Tomography, X-Ray Computed , Adenocarcinoma/diagnosis , Adenocarcinoma/metabolism , Adult , Aged , Aged, 80 and over , Antigens, Neoplasm/metabolism , Biopsy, Fine-Needle , Carcinoembryonic Antigen/metabolism , Carcinoma, Large Cell/diagnosis , Carcinoma, Large Cell/metabolism , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/metabolism , Cell Cycle Proteins , Cohort Studies , DNA-Binding Proteins , Female , Follow-Up Studies , Humans , Immunoradiometric Assay , Keratin-19/metabolism , Male , Middle Aged , Neoplasm Staging , Nuclear Proteins/metabolism , Phosphoproteins/metabolism , Prognosis , Prospective Studies , ROC Curve , Sensitivity and Specificity , Serpins/metabolism , Survival Rate
16.
Stroke ; 42(9): 2471-7, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21757676

ABSTRACT

BACKGROUND AND PURPOSE: A noninvasive method with high reliability and accuracy comparable to transesophageal echocardiography for identification of left atrial appendage thrombus would be of significant clinical value. The aim of this study was to assess the diagnostic performance of a dual-enhanced cardiac CT protocol for detection of left atrial appendage thrombi and for differentiation between thrombus and circulatory stasis in patients with stroke. METHODS: We studied 83 consecutive patients with stroke (56 men and 27 women; mean age, 62.6 years) who had high risk factors for thrombus formation and had undergone both dual-source CT and transesophageal echocardiography within a 3-day period. CT was performed with prospective electrocardiographic gating, and scanning began 180 seconds after the test bolus. RESULTS: Among the 83 patients, a total of 13 thrombi combined with spontaneous echo contrast and 14 spontaneous echo contrasts were detected by transesophageal echocardiography. All 13 thrombi combined with spontaneous echo contrast were correctly diagnosed on CT. Using transesophageal echocardiography as the reference standard, the overall sensitivity and specificity of CT for the detection of thrombi and circulatory stasis in the left atrial appendage were 96% (95% CI, 78% to 99%), and 100% (95% CI, 92% to 100%), respectively. On CT, the mean left atrial appendage/ascending aorta Hounsfield unit ratios were significantly different between thrombus and circulatory stasis (0.15 Hounsfield unit versus 0.27 Hounsfield unit, P=0.001). The mean effective radiation dose was 3.11 mSv. CONCLUSIONS: Dual-enhanced cardiac CT with prospective electrocardiographic gating is a noninvasive and sensitive modality for detecting left atrial appendage thrombus with an acceptable radiation dose.


Subject(s)
Atrial Appendage/diagnostic imaging , Atrial Appendage/ultrastructure , Echocardiography, Transesophageal/methods , Thrombosis/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity
17.
Am J Cardiol ; 108(4): 536-40, 2011 Aug 15.
Article in English | MEDLINE | ID: mdl-21624544

ABSTRACT

Recently contrast-enhanced cardiac computed tomography (CT) was found to be useful for imaging the left atrium and pulmonary veins (PVs) before radiofrequency catheter ablation in patients with atrial fibrillation. However, the risks of contrast agent in patients with impaired renal function must be considered. We investigated the accuracy of low-dose electrocardiographically synchronized nonenhanced cardiac CT (NECT) for identifying PV anatomy. One hundred eight consecutive patients who underwent cardiac CT before radiofrequency catheter ablation of atrial fibrillation were included. Nonenhanced cardiac computed tomogram was retrospectively evaluated for each patient by 2 radiologists for the following PV anatomy: conventional pattern, conjoined ostium, and accessory PVs with number and location. Sensitivity and specificity for variations in PVs were calculated using contrast-enhanced cardiac computed tomogram as the reference standard. Detection rates for each variation were also calculated. Twenty-one right PV (RPV) variations and 11 left PV (LPV) variations were observed. NECT showed a high diagnostic performance in detecting variations in PVs for the 2 observers. For RPV variations overall sensitivity was 97.6% and specificity was 96.6%. For LPV variations overall sensitivity was 90.9% and specificity was 97.9%. Overall detection rates for variation between the 2 observers were 97.1% for accessory RPV from the right middle lobe, 100% for 4 ostia with accessory RPV from the right middle lobe and accessory RPV from the superior segment of the right lower lobe, 100% for accessory RPV from the superior segment of the right lower lobe, 88.9% for conjoined ostium of the LPV, and 100% for accessory LPV from the left lingular segment. In conclusion, variations in PV anatomy were detected with great accuracy by NECT.


Subject(s)
Atrial Fibrillation/therapy , Catheter Ablation , Heart Atria/diagnostic imaging , Pulmonary Veins/diagnostic imaging , Electrocardiography , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed
18.
Korean J Radiol ; 12(2): 252-5, 2011.
Article in English | MEDLINE | ID: mdl-21430944

ABSTRACT

A diffuse interstitial infiltrative pattern of lung metastasis in a patient with malignant melanoma is rare and can be confused with benign conditions such as pulmonary edema or drug-induced pneumonitis. We experienced a case of diffuse interstitial infiltrative lung metastasis in malignant melanoma in a 37-year-old man. This case was confirmed by a transbronchial lung biopsy. We herein describe the findings on CT and positron emission tomography scan.


Subject(s)
Lung Neoplasms/secondary , Melanoma/secondary , Skin Neoplasms/pathology , Adult , Biopsy , Diagnosis, Differential , Fatal Outcome , Humans , Lung Neoplasms/diagnosis , Lymphatic Metastasis , Male , Melanoma/diagnosis , Positron-Emission Tomography , Radiography, Thoracic , Tomography, X-Ray Computed
19.
Eur Radiol ; 21(2): 232-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20730613

ABSTRACT

OBJECTIVE: We evaluated radiation doses, complication rates, and diagnostic accuracy for CT-guided percutaneous needle aspiration biopsy (NAB) procedures of pulmonary lesions performed with or without fluoroscopic guidance. METHODS: A total of 142 patients were prospectively enrolled to receive CT-guided NAB with (Group I, n = 72) or without (Group II, n = 70) fluoroscopic guidance. Outcome measurements were patient and doctor radiation dose, and complication rate. Sensitivity, specificity and accuracy were calculated based on 123 NAB results. RESULTS: The mean estimated effective patient radiation dose was 6.53 mSv in Group I and 2.72 mSv in Group II (p < 0.001). The mean estimated effective doctor dose was 0.054 mSv in Group I and 0.029 mSv in Group II (p < 0.001). The complication rate was significantly different between the two groups (13.4% versus 31.4%, p = 0.012). Sensitivity, specificity and accuracy for diagnosing pulmonary lesions were 97.8%, 100% and 98.4% in group I and 95.3%, 100% and 89.5% in group II (p > 0.05). CONCLUSIONS: CT fluoroscopy-guided NAB of pulmonary lesions provides high diagnostic accuracy and can be performed with significantly fewer complications. However, radiation exposure to both patient and doctor were significantly higher than conventional CT-guided NAB.


Subject(s)
Biopsy, Needle/statistics & numerical data , Lung Neoplasms/diagnosis , Lung Neoplasms/epidemiology , Postoperative Complications/epidemiology , Radiation Dosage , Radiography, Interventional/statistics & numerical data , Tomography, X-Ray Computed/statistics & numerical data , Comorbidity , Female , Humans , Incidence , Male , Middle Aged , Prospective Studies , Radiometry/statistics & numerical data , Reproducibility of Results , Republic of Korea/epidemiology , Risk Assessment/methods , Risk Factors , Sensitivity and Specificity
20.
Clin Imaging ; 34(5): 400-3, 2010.
Article in English | MEDLINE | ID: mdl-20813309

ABSTRACT

Torsion of the remaining lung lobe after lobectomy is a rare complication, and sometimes, diagnosis can be difficult. But early detection is important to prevent resection and fatal complication. We present a case of left lower lobe torsion with reconstructed image of multidetector computed tomography (MDCT) findings, which propose a possibility of early detection on retrospective review after surgical reduction. Multiplanar reconstruction of MDCT image, 3-dimensional CT angiography, and CT bronchography could provide important diagnostic clues.


Subject(s)
Carcinoma, Neuroendocrine/surgery , Image Processing, Computer-Assisted/methods , Lung Diseases/diagnosis , Lung Neoplasms/surgery , Postoperative Complications/diagnosis , Tomography, X-Ray Computed/methods , Torsion Abnormality/diagnosis , Bronchography/methods , Diagnosis, Differential , Dyspnea/etiology , Early Diagnosis , Female , Humans , Imaging, Three-Dimensional/methods , Lung/diagnostic imaging , Lung/surgery , Lung Diseases/complications , Lung Diseases/surgery , Middle Aged , Postoperative Complications/surgery , Pulmonary Veins/diagnostic imaging , Torsion Abnormality/complications , Torsion Abnormality/surgery
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