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1.
J Hepatol ; 70(3): 412-422, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30389550

RESUMO

BACKGROUND & AIMS: Non-selective beta-blockers (NSBBs) are the mainstay of primary prophylaxis of esophageal variceal bleeding in patients with liver cirrhosis. We investigated whether non-invasive markers of portal hypertension correlate with hemodynamic responses to NSBBs in cirrhotic patients with esophageal varices. METHODS: In this prospective cohort study, 106 cirrhotic patients with high-risk esophageal varices in the derivation cohort received carvedilol prophylaxis, and completed paired measurements of hepatic venous pressure gradient, liver stiffness (LS), and spleen stiffness (SS) at the beginning and end of dose titration. LS and SS were measured using acoustic radiation force impulse imaging. A prediction model for hemodynamic response was derived, and subject to an external validation in the validation cohort (63 patients). RESULTS: Hemodynamic response occurred in 59 patients (55.7%) in the derivation cohort, and in 33 patients (52.4%) in the validation cohort, respectively. Multivariate logistic regression analysis identified that ΔSS was the only significant predictor of hemodynamic response (odds ratio 0.039; 95% confidence interval 0.008-0.135; p <0.0001). The response prediction model (ModelΔSS = 0.0490-2.8345 × ΔSS; score = (exp[ModelΔSS])/(1 + exp[ModelΔSS]) showed good predictive performance (area under the receiver-operating characteristic curve [AUC] = 0.803) using 0.530 as the threshold value. The predictive performance of the ModelΔSS in the validation set improved using the same threshold value (AUC = 0.848). CONCLUSION: A new model based on dynamic changes in SS exhibited good performance in predicting hemodynamic response to NSBB prophylaxis in patients with high-risk esophageal varices. LAY SUMMARY: Non-selective beta-blockers are the mainstay of primary prophylaxis to prevent variceal bleeding in patients with cirrhosis and high-risk esophageal varices. This prospective study showed that a prediction model based on changes in spleen stiffness before vs. after dose titration might be a non-invasive marker for response to prophylactic non-selective beta-blocker (carvedilol) therapy in patients with cirrhosis and high-risk esophageal varices. ClinicalTrials.gov Identifier: NCT01943318.


Assuntos
Carvedilol/administração & dosagem , Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Hipertensão Portal , Cirrose Hepática , Baço/patologia , Antagonistas Adrenérgicos beta/administração & dosagem , Quimioprevenção/métodos , Regras de Decisão Clínica , Técnicas de Imagem por Elasticidade/métodos , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/prevenção & controle , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão Portal/diagnóstico , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Fígado/patologia , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
2.
Eur Radiol ; 28(8): 3484-3493, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29352379

RESUMO

PURPOSE: To investigate added value of MRI to preoperative staging MDCT for evaluation of focal liver lesions (FLLs) in potentially resectable pancreatic ductal adenocarcinomas (PDACs). MATERIALS AND METHODS: In patients with potentially resectable PDACs after staging MDCT (n=167), characteristics of FLLs were scored as benign, indeterminate or metastases on an MDCT set and combined MDCT and MRI set by two readers, independently. Size of hepatic lesions was measured and detection rate of hepatic metastasis unsuspected by MDCT and diagnostic yield of MRI for FLLs were assessed. RESULTS: Reader-averaged figure-of-merit (FOM) of the combined set was significantly higher than that of MDCT alone (0.94 vs. 0.86, p=.028). In the negative-on-CT group, the diagnostic yield of MRI was 1.5-2.3% (2/133 and 3/133 for readers 1 and 2, respectively). In the indeterminate-on-CT group, MRI yield was 10.5-13.6% (2/19 and 3/22) and in patients with suspicious-metastasis-on-CT, 8.3-26.7% (1/12 and 4/15). All lesions with false-positive and false-negative CT findings were ≤1 cm. CONCLUSION: In potentially resectable PDACs, addition of MRI with DWI can provide significantly better diagnostic performance in characterization of focal liver lesions, especially for small-sized (≤ 1 cm) MDCT-indeterminate or suspicious metastasis lesions, aiding in determination of appropriate operation candidates. KEY POINTS: • Addition of MRI provides better diagnostic performance in characterization of liver lesions. • Combined interpretation of MRI and MDCT provided less frequent indeterminate liver lesions. • Diagnostic yield of MRI was high in CT-indeterminate or suspicious metastatic lesions. • Operation candidates can be determined with greater confidence in potentially resectable PDACs.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Tomografia Computadorizada Multidetectores/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
AJR Am J Roentgenol ; 211(1): 114-120, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29702017

RESUMO

OBJECTIVE: The objective of our study was to evaluate the performance of multiparametric MRI with Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) for detecting prostate cancer (PCA) and clinically significant PCA through this per-lesion one-to-one correlation study between pathologically proven lesions and MRI-visible lesions. MATERIALS AND METHODS: A total of 93 PCA lesions from 44 patients who underwent radical prostatectomy were included in this retrospective study. Two radiologists scored every visible lesion with a PI-RADSv2 score of 3, 4, or 5 in each patient's multiparametric MRI examination using PI-RADSv2. A per-lesion one-to-one correlation between MRI-visible lesions and pathologically confirmed PCA lesions was conducted during regular radiology-pathology meetings at our center. The detection rates of clinically significant PCA and the proportions of clinically significant PCAs from MRI-visible and MRI-invisible PCAs were calculated. The performance of PI-RADSv2 for detecting clinically significant PCA was evaluated using the positive predictive value (PPV), negative predictive value (NPV), and area under the ROC curve (AUC) value. RESULTS: Using a PI-RADSv2 score of 3, 4, or 5 as an MRI-visible lesion, 46.88% of clinically significant PCA lesions were detected. The PPV, NPV, and AUC were 96.77%, 45.16%, and 0.72, respectively. Tumor volume and secondary Gleason grade showed a statistically significant difference between MRI-visible and MRI-invisible clinically significant PCAs. CONCLUSION: Multiparametric MRI with PI-RADSv2 missed a considerable number of clinically significant PCA lesions in this per-lesion analysis, causing a relatively low NPV and diagnostic performance compared with previous per-patient studies. However, the high PPV indicates that multiparametric MRI with PI-RADSv2 may be useful for follow-up of active surveillance and planning focal therapy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Meios de Contraste , Erros de Diagnóstico/estatística & dados numéricos , Humanos , Masculino , Meglumina , Pessoa de Meia-Idade , Gradação de Tumores , Compostos Organometálicos , Valor Preditivo dos Testes , Prostatectomia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
5.
Eur Radiol ; 27(4): 1740-1747, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27510623

RESUMO

OBJECTIVES: The purpose of this study is to evaluate high-resolution ultrasound and magnetic resonance imaging (MRI) in monitoring of cholangiocarcinoma in the hamsters with C. sinensis infection and N-nitrosodimethylamine (NDMA). MATERIALS AND METHODS: Twenty-four male Syrian golden hamsters of were divided into four groups composed of five hamsters as control, five hamsters receiving 30 metacercariae of C. sinensis per each hamster, five hamsters receiving NDMA in drinking water, and nine hamsters receiving both metacercariae and NDMA. Ultrasound was performed every other week from baseline to the 12th week of infection. MRI and histopathologic examination was done from the 4th week to 12th week. RESULTS: Cholangiocarcinomas appeared as early as the 6th week of infection. There were 12 cholangiocarcinomas, nine and ten of which were demonstrated by ultrasound and MRI, respectively. Ultrasound and MRI findings of cholangiocarcinomas in the hamsters were similar to those of the mass-forming intrahepatic cholangiocarcinomas in humans. Ultrasound and MRI also showed other findings of disease progression such as periductal increased echogenicity or signal intensity, ductal dilatation, complicated cysts, and sludges in the gallbladder. CONCLUSIONS: High-resolution ultrasound and MRI can monitor and detect the occurrence of cholangiocarcinoma in the hamsters non-invasively. KEY POINTS: • High-resolution ultrasound and MRI can monitor occurrence of cholangiocarcinoma in the hamsters. • Cholangiocarcinomas were detected as early as the 6th week after C. sinensis infection. • Axial T2-weighted MRI demonstrated cholangiocarcinomas and various inflammatory findings in the hamsters.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Animais , Neoplasias dos Ductos Biliares/etiologia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/etiologia , Colangiocarcinoma/patologia , Clonorquíase/complicações , Cocarcinogênese , Cricetinae , Dimetilnitrosamina , Modelos Animais de Doenças , Progressão da Doença , Imageamento por Ressonância Magnética/métodos , Masculino , Mesocricetus , Ultrassonografia/métodos
6.
Radiology ; 277(3): 881-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26147680

RESUMO

PURPOSE: To compare the reliability of acoustic radiation force impulse (ARFI) imaging and supersonic shear imaging (SSI) in measurement of liver stiffness. MATERIALS AND METHODS: This study was approved by the institutional review board, and written informed consent was obtained for all patients. Seventy-nine patients (25 healthy patients, 26 with Child-Pugh class A, and 28 with Child-Pugh class B or C) were enrolled and analyzed from April 2012 to April 2013. In each patient, three abdominal radiologists performed nine measurements of hepatic shear-wave speed with both ARFI imaging and SSI on the same day. Four weeks later, a second session was performed with the same protocol. Interobserver and intraobserver agreements were calculated by using intraclass correlation coefficients. Technical failures and measurement time were evaluated. RESULTS: There were four technical failures in the SSI group and one in the ARFI group (P = .375). The overall interobserver agreement of ARFI imaging was significantly higher than that of SSI (0.941 vs 0.828, P < .001). The overall intraobserver agreement of ARFI imaging was significantly higher than that of SSI (0.915 vs 0.829, P < .001). The overall shear-wave speed measured with SSI was higher than that measured with ARFI imaging (2.04 m/sec ± 0.88 vs 1.80 m/sec ± 0.81, P < .001). The measurement time of SSI was longer than that of ARFI imaging (310.8 seconds ± 88.5 vs 84.5 seconds ± 15.4, P < .001). CONCLUSION: ARFI imaging was more reliable than SSI in measurement of liver stiffness. The hepatic shear-wave speed measured with SSI was higher than that measured with ARFI imaging, which means that the shear-wave speeds measured with ARFI imaging and SSI cannot be used interchangeably.


Assuntos
Diagnóstico por Imagem/métodos , Técnicas de Imagem por Elasticidade , Cirrose Hepática/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Resistência ao Cisalhamento
7.
AJR Am J Roentgenol ; 205(6): W594-611, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26587949

RESUMO

OBJECTIVE: The objective of our study was to prospectively evaluate the initial diagnostic performance and learning curve of a community of radiologists and residents in interpreting 2-mSv appendiceal CT. SUBJECTS AND METHODS: We included 46 attending radiologists and 153 radiology residents from 22 hospitals who completed an online training course of 30 2-mSv CT cases. Appendicitis was confirmed in 14 cases. Most of the readers had limited (≤ 10 cases, n = 32) or no (n = 118) prior experience with low-dose appendiceal CT. The order of cases was randomized for each reader. A multireader multicase ROC analysis was performed. Generalized estimating equations were used to model the learning curves in diagnostic performance. RESULTS: Diagnostic performance gradually improved with years of training. The average AUC was 0.94 (95% CI, 0.90-0.98), 0.92 (0.88-0.96), 0.90 (0.85-0.96), and 0.86 (0.80-0.92) for the attending radiologists, senior residents, 2nd-year residents, and 1st-year residents, respectively. We did not observe any notable intrareader learning curves over the training course of the 30 cases except a decrease in reading time. Diagnostic accuracy and sensitivity were significantly affected by the reader training level and prior overall experience with appendiceal CT but not by the prior specific experience with low-dose appendiceal CT. CONCLUSION: The learning curve is likely prolonged and forms gradually over years by overall radiology training and clinical experience in general rather than by experience with low-dose appendiceal CT specifically.


Assuntos
Apendicite/diagnóstico por imagem , Competência Clínica , Educação de Pós-Graduação em Medicina , Radiologia/educação , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Internato e Residência , Masculino , Doses de Radiação , Sensibilidade e Especificidade
8.
AJR Am J Roentgenol ; 203(1): 3-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24951190

RESUMO

OBJECTIVE: The purpose of this study was to simulate a mobile consultation in patients with inconclusive diagnosis of appendicitis made by on-call radiologists, as well as to measure the diagnostic confidence and performance of the mobile consultation. MATERIALS AND METHODS: Two off-site abdominal radiologists interpreted the CT images from 68 patients (including 29 patients with confirmed appendicitis) on a smart-phone for whom the preliminary CT reports by 25 in-house on-call radiologists were inconclusive. The smartphone readings were compared with the preliminary reports by on-call radiologists and with the original final reports by in-house abdominal radiologists. Heat maps, kappa statistics, Wilcoxon signed-rank tests, and ROC curves were used for data analysis. RESULTS: The heat maps and kappa statistics showed that the smartphone readings were more similar to the final reports than to the preliminary reports. In diagnosing or ruling out appendicitis, the smartphone readings were more confident than the preliminary reports (p ≤ 0.01) and did not significantly differ in diagnostic confidence from the final reports (p ≥ 0.19). The AUCs of the smartphone readings (0.91 and 0.92) did not differ significantly from those of the preliminary (0.85) or final (0.97) reports (p ≥ 0.09). CONCLUSION: With the given study sample, the diagnostic performance of the off-site smartphone readings did not differ significantly from that of the in-house preliminary reports. However, the smartphone readings provided higher diagnostic confidence than the preliminary reports.


Assuntos
Apendicite/diagnóstico por imagem , Telefone Celular , Consulta Remota , Telerradiologia/métodos , Tomografia Computadorizada Espiral , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Curva ROC , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Estatísticas não Paramétricas
9.
Abdom Imaging ; 39(6): 1350-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24802548

RESUMO

PURPOSE: To determine the computed tomographic (CT) findings of acute pelvic inflammatory disease (PID). METHODS: This retrospective, single-institution case-control study was approved by our institutional review board, and the informed consent was waived owing to the retrospective nature of the study. CT images of 32 women with clinically proven acute PID and 32 control subjects with other conditions of similar presentation were retrospectively reviewed. Analysis of CT findings included hepatic capsular enhancement, pelvic fat haziness, complicated ascites, uterine serosal enhancement, tubal thickening, endometritis, and oophoritis. Comparison of CT findings was performed with the Chi square test or the Fisher exact test and logistic regression analysis was used to determine significant CT findings in predicting PID. RESULTS: The CT findings that showed a statistically significant difference were hepatic capsular enhancement on late arterial phase (p = 0.003), pelvic fat haziness (p = 0.045), and tubal thickening (p = 0.001). Subsequent multivariate logistic regression analysis revealed that the presence of hepatic capsular enhancement on late arterial phase and tubal thickening were significant predictors of PID (hepatic capsular enhancement on late arterial phase, p = 0.015, odds ratio [OR] = 4.8; tubal thickening, p = 0.005, OR = 10.5). CONCLUSION: Diagnostic morphological CT findings in women with clinically proven PID and acute abdominal pain include hepatic capsular enhancement on late arterial phase and tubal thickening.


Assuntos
Doença Inflamatória Pélvica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Adolescente , Adulto , Estudos de Casos e Controles , Meios de Contraste , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Iohexol , Pessoa de Meia-Idade , Variações Dependentes do Observador , Pelve/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Estudos Retrospectivos , Adulto Jovem
10.
Cardiovasc Intervent Radiol ; 42(11): 1619-1626, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471721

RESUMO

PURPOSE: This study evaluates the image quality of lower extremity CT venography reconstructed with orthopedic metal artifact reduction (O-MAR) in patients with unilateral or bilateral metallic prostheses in the hip or knee. METHODS: This retrospective study was approved by our institutional review board, and informed consent was waived. Twenty-nine patients of lower extremity CT with 51 metallic hip or knee prostheses were reconstructed to both standard CT images and O-MAR images. The subjective image quality and vessel conspicuity for both images were evaluated by two readers using five-point scales (0-4). Vessel conspicuity scores of 3 or 4 were considered diagnostically acceptable. Image noise was measured in the air and subcutaneous fat. RESULTS: O-MAR images showed significantly higher scores of subjective image quality (p < .001) and vessel conspicuity (p = .002) than standard CT images. Diagnostic acceptance of vessel conspicuity was not significantly different between O-MAR images and standard CT images (p = 1.000). O-MAR images showed significantly less image noise than conventional CT images (p < .001 for both air and subcutaneous fat). CONCLUSION: O-MAR may be an effective solution for the metal artifacts in lower extremity CT venography; however, the distance between prostheses and vessels affects the diagnostic acceptance in patients with metallic hip or knee prostheses. LEVEL OF EVIDENCE: Level 4, Case Series.


Assuntos
Artefatos , Extremidade Inferior/diagnóstico por imagem , Flebografia/métodos , Próteses e Implantes , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Extremidade Inferior/irrigação sanguínea , Masculino , Metais , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
ChemSusChem ; 12(20): 4645-4654, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31419074

RESUMO

Sodium batteries have been recognized as a promising alternative to lithium-ion batteries. However, the liquid electrolyte used in these batteries has inherent safety problems. Polymer electrolytes have been considered as safer and more reliable electrolyte systems for rechargeable batteries. Herein, a thermoplastic polyurethane elastomer-based gel polymer electrolyte with high ionic conductivity and high elasticity was reported. It had an ambient-temperature ionic conductivity of 1.5 mS cm-1 and high stretchability, capable of withstanding 610 % strain. Coordination between Na+ ions and polymer chains increased the degree of salt dissociation in the gel polymer electrolyte compared with the liquid electrolyte. An Na/Na3 V2 (PO4 )3 cell assembled with gel polymer electrolyte exhibited good cycling performance in terms of discharge capacity, cycling stability, and rate capability, which was owing to the effective trapping ability of organic solvents in the polymer matrix and uniform flux of sodium ions through the gel polymer electrolyte.

12.
Radiat Res ; 192(1): 23-27, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31021708

RESUMO

Epidemiologic studies using clinical indicators are limited in the assessment of the biological effects of low-dose ionizing radiation for medical purposes. We evaluated the biological effect of low-dose radiation by comparing translocation frequencies in patients with repeated computed tomography (CT) exposure and CT-naïve patients. The goal of this prospective case-control study was to determine whether repeated CT exposure is associated with increased frequency in chromosomal translocations. Two cohorts, comprised of case patients with a history of repeated CT exposure and age- and sex-matched CT-naïve control patients (n = 48 per cohort), were consecutively enrolled in this single-institution study. CT-radiation exposure was estimated using dose-length products, and translocation frequencies of peripheral blood lymphocytes were assessed using whole chromosome paints by fluorescence in situ hybridization (FISH). Comparison of translocation frequencies between cases and controls was performed using the Wilcoxon rank sum test (paired samples), and the relationship between cumulative radiation exposure and translocation frequency was assessed using a partial correlation analysis. Translocation frequencies were significantly different between cases and controls (P = 0.0003). The median translocation frequency was 7 [95% confidence interval (CI): 6, 8] for cases and 4 (95% CI: 3, 6) for controls. By using cumulative radiation exposure as the effect variable and translocation frequency as the response variable, we found a significant correlation between cumulative radiation exposure and translocation frequency (r = 0.6579, P < 0.0001). Chromosomal translocations were more frequent with repeated CT-exposed patients than in CT-naïve patients, and a positive dose-response relationship was present between cumulative radiation exposure and translocation frequency.


Assuntos
Exposição à Radiação/efeitos adversos , Tomografia Computadorizada por Raios X/efeitos adversos , Translocação Genética/efeitos da radiação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
13.
PLoS One ; 13(7): e0200190, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29995921

RESUMO

OBJECTIVE: The purpose of our study was to assess computed tomographic (CT) findings of adnexal torsion through a matched case-control analysis. MATERIALS AND METHODS: This retrospective, single-institution case-control study included 43 women with adnexal torsion and 43 age- and ovarian mass-matched control women. CT images were evaluated independently by two readers for the following: prominent peripheral follicles, uterine deviation, thickened pedicles, a whirl sign, and a navel sign. Comparisons of CT findings were performed using the Chi square test and receiver operating characteristic (ROC) curves were obtained to assess the diagnostic performance. Differences between the areas under the ROC curves (AUCs) were compared by using a Delong test. RESULTS: The CT findings significant for adnexal torsion were uterine deviation toward the side of the affected ovary (P = < .01 for reader 1 and P = .02 for reader 2) and thickened pedicles with ancillary findings including a whirl sign, a navel sign, and uterine deviation facing thickened pedicles (P < .01 for both readers). Thickened pedicles with ancillary findings had the highest diagnostic accuracy, as measured with ROC curves (AUC, 0.86 in reader 1 and 0.85 in reader 2). Combining uterine deviation toward the side of the affected ovary with thickened pedicles with ancillary findings did not increase the performance relative to that of thickened pedicles with ancillary findings alone. CONCLUSIONS: Thickened pedicles with ancillary findings including a whirl sign, a navel sign, and uterine deviation facing thickened pedicles could be helpful for the diagnosis of adnexal torsion.


Assuntos
Doenças dos Anexos/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Anormalidade Torcional/diagnóstico por imagem , Anexos Uterinos/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Adulto Jovem
14.
ACS Appl Mater Interfaces ; 10(1): 687-695, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29235851

RESUMO

A major challenge of lithium-oxygen batteries is to develop a stable electrolyte not only to suppress solvent evaporation and lithium dendrite growth, but also to resist the attack by superoxide anion radical formed at the positive electrode. The present study demonstrates the enhancement of cycling stability by addressing the above challenges through the use of three-dimensional semi-interpenetrating polymer network (semi-IPN) composite gel polymer electrolyte when fabricating the lithium-oxygen cell. The semi-IPN composite gel electrolyte synthesized from poly(methyl methacrylate), divinylbenzene, and vinyl-functionalized silica effectively encapsulated electrolyte solution and exhibited stable interfacial characteristics toward lithium electrodes. Matrix polymers in the semi-IPN composite gel electrolyte also retained high stability without any decomposition by superoxide anion radicals during cycling. The lithium-oxygen cell employing semi-IPN composite gel polymer electrolyte was shown to cycle with good capacity retention at 0.25 mAh cm-2. The semi-IPN composite gel electrolyte is one of the promising electrolytes for the stable lithium-oxygen battery with high energy density.

15.
Korean J Radiol ; 19(6): 1053-1065, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30386137

RESUMO

Objective: To evaluate the clinical impact of using registration software for ablative margin assessment on pre-radiofrequency ablation (RFA) magnetic resonance imaging (MRI) and post-RFA computed tomography (CT) compared with the conventional side-by-side MR-CT visual comparison. Materials and Methods: In this Institutional Review Board-approved prospective study, 68 patients with 88 hepatocellulcar carcinomas (HCCs) who had undergone pre-RFA MRI were enrolled. Informed consent was obtained from all patients. Pre-RFA MRI and post-RFA CT images were analyzed to evaluate the presence of a sufficient safety margin (≥ 3 mm) in two separate sessions using either side-by-side visual comparison or non-rigid registration software. Patients with an insufficient ablative margin on either one or both methods underwent additional treatment depending on the technical feasibility and patient's condition. Then, ablative margins were re-assessed using both methods. Local tumor progression (LTP) rates were compared between the sufficient and insufficient margin groups in each method. Results: The two methods showed 14.8% (13/88) discordance in estimating sufficient ablative margins. On registration software-assisted inspection, patients with insufficient ablative margins showed a significantly higher 5-year LTP rate than those with sufficient ablative margins (66.7% vs. 27.0%, p = 0.004). However, classification by visual inspection alone did not reveal a significant difference in 5-year LTP between the two groups (28.6% vs. 30.5%, p = 0.79). Conclusion: Registration software provided better ablative margin assessment than did visual inspection in patients with HCCs who had undergone pre-RFA MRI and post-RFA CT for prediction of LTP after RFA and may provide more precise risk stratification of those who are treated with RFA.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Ablação por Radiofrequência , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Progressão da Doença , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Software , Resultado do Tratamento
17.
Korean J Radiol ; 18(4): 607-614, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670155

RESUMO

OBJECTIVE: To evaluate the determinant pretreatment CT findings that can predict surgical intervention for patients suffering from corpus luteal cyst rupture with hemoperitoneum. MATERIALS AND METHODS: From January 2009 to December 2014, a total of 106 female patients (mean age, 26.1 years; range, 17-44 years) who visited the emergency room of our institute for acute abdominal pain and were subsequently diagnosed with ruptured corpus luteal cyst with hemoperitoneum were included in the retrospective study. The analysis of CT findings included cyst size, cyst shape, sentinel clot sign, ring of fire sign, hemoperitoneum depth, active bleeding in portal phase and attenuation of hemoperitoneum. The comparison of CT findings between the surgery and conservative management groups was performed with the Mann-Whitney U test or chi-square test. Logistic regression analysis was used to determine significant CT findings in predicting surgical intervention for a ruptured cyst. RESULTS: Comparative analysis revealed that the presence of active bleeding and the hemoperitoneum depth were significantly different between the surgery and conservative management groups and were confirmed as significant CT findings for predicting surgery, with adjusted odds ratio (ORs) of 3.773 and 1.318, respectively (p < 0.01). On the receiver-operating characteristic curve analysis for hemoperitoneum depth, the optimal cut-off value was 5.8 cm with 73.7% sensitivity and 58.6% specificity (Az = 0.711, p = 0.004). In cases with a hemoperitoneum depth > 5.8 cm and concurrent active bleeding, the OR for surgery increased to 5.786. CONCLUSION: The presence of active bleeding and the hemoperitoneum depth on a pretreatment CT scan can be predictive warning signs of surgery for a patient with a ruptured corpus luteal cyst with hemoperitoneum.


Assuntos
Hemoperitônio/patologia , Cistos Ovarianos/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Dor Abdominal/etiologia , Adulto , Área Sob a Curva , Feminino , Hemoperitônio/complicações , Hemorragia/etiologia , Humanos , Razão de Chances , Cistos Ovarianos/complicações , Cistos Ovarianos/cirurgia , Curva ROC , Estudos Retrospectivos , Ruptura Espontânea , Estatísticas não Paramétricas , Adulto Jovem
18.
Abdom Radiol (NY) ; 42(3): 900-907, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27730329

RESUMO

PURPOSE: To assess the effectiveness of reduced-radiation-dose computed tomography (CT) protocols in the tracing of the ureter in patients with suspected renal colic. METHODS: The study was approved by our institutional review board, and informed consent was obtained from the participants. From July 2012 to April 2014, 310 consecutive patients with suspected urolithiasis were recruited to undergo unenhanced CT at 280 (n = 62), 200 (n = 62), 140 (n = 62), 100 (n = 62), and 70 (n = 62) reference mA seconds (mAs) while keeping other imaging parameters constant. Images were independently and randomly reviewed by two radiologists blinded to the study to determine the tracing rates of the ureter and the acceptable rates of image quality according to different tube charge settings. RESULTS: A significant linear association was noted between tube charge settings, the rates for tracing of the ureter, and the acceptability of image quality (linear-by-linear association; p = 0.000 in all rates for both readers). The 140 reference mAs is the point at which the tracing rates deteriorate rapidly, with the tracing rate of 41.5% (95% CI 32.6%-51.0%) in reader 1 and 51.9% (95% CI 42.5%-61.2%) in reader 2, and with the acceptable rate of 82.3% (95% CI 70.8%-90.0%) in reader 1 and 96.8% (95% CI 88.3%-99.8%) in reader 2. CONCLUSION: Decreasing the tube charge settings from 280 to 70 reference mAs resulted in a significant reduction in the tracing rate of the ureter, with 140 reference mAs being the breaking point.


Assuntos
Doses de Radiação , Cólica Renal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ureter/diagnóstico por imagem , Urolitíase/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
PLoS One ; 12(11): e0188321, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29176844

RESUMO

The diagnostic performance of supersonic shear imaging (SSI) in comparison with those of transient elastography (TE) and acoustic radiation force impulse imaging (ARFI) for staging fibrosis in nonalcoholic fatty liver disease (NAFLD) patients has not been fully assessed, especially in Asian populations with relatively lean NAFLD compared to white populations. Thus, we focused on comparing the diagnostic performances of TE, ARFI, and SSI for staging fibrosis in a head-to-head manner, and identifying the clinical, anthropometric, biochemical, and histological features which might affect liver stiffness measurement (LSM) in our prospective biopsy-proven NAFLD cohort. In this study, ninety-four patients with biopsy-proven NAFLD were included prospectively. Liver stiffness was measured using TE, SSI, and ARFI within 1 month of liver biopsy. The diagnostic performance for staging fibrosis was assessed using receiver operating characteristic (ROC) analysis. Anthropometric data were evaluated as covariates influencing LSM by regression analyses. Liver stiffness correlated with fibrosis stage (p < 0.05); the area under the ROC curve of TE (kPa), SSI (kPa), and ARFI (m/s) were as follows: 0.757, 0.759, and 0.657 for significant fibrosis and 0.870, 0.809, and 0.873 for advanced fibrosis. Anthropometric traits were significant confounders affecting SSI, while serum liver injury markers significantly confounded TE and ARFI. In conclusion, the LSM methods had similar diagnostic performance for staging fibrosis in patients with NAFLD. Pre-LSM anthropometric evaluation may help predict the reliability of SSI.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Área Sob a Curva , Fenômenos Biomecânicos , Feminino , Humanos , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Estudos Prospectivos , Curva ROC
20.
ACS Appl Mater Interfaces ; 8(47): 32300-32306, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27933816

RESUMO

Lithium-oxygen batteries have attracted great attention for advanced energy storage systems because of their high specific energy. The enhancement of the interfacial stability of lithium negative electrodes is one of the many technical challenges toward high safety and long life lithium-oxygen batteries due to their high reactivity toward organic electrolytes and the lithium dendrite growth during the repeated cycling. Herein, we demonstrate that the protective layer comprising conductive polymer and AlF3 particles on lithium metal stabilized the lithium electrode by effectively reducing the reductive decomposition of the liquid electrolyte and suppressing the growth of lithium dendrite. As a result, the cycling performance of a lithium-oxygen cell assembled with a surface-modified lithium electrode was remarkably improved as compared to a cell with a pristine lithium electrode.

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