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BACKGROUND: The demand for homogeneous and higher vascular contrast enhancement is critical to provide an appropriate interpretation of abnormal vascular findings in coronary computed tomography angiography (CTA). PURPOSE: To evaluate the effect of various contrast media concentrations (Iohexol-370, Iohexol-300, Iohexol-240) and image reconstructions (filtered back projection [FBP], hybrid iterative reconstruction [IR], and deep learning reconstruction [DLR]) on coronary CTA. MATERIAL AND METHODS: A total of 63 patients referred for coronary CTA between July and October 2021 were enrolled in this prospective study, and they randomly received one of three contrast media. CTA images were reconstructed with FBP, hybrid IR, and DLR. The CT attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated for all three images. The images were subjectively evaluated by two radiologists in terms of overall image quality, artifacts, image noise, and vessel wall delineation on a 5-point Likert scale. RESULTS: The application of DLR resulted in significantly lower image noise; higher CT attenuation, SNR, and CNR; and better subjective analysis among the three different concentrations of contrast media groups (P < 0.001). There was no significant difference in the CT attenuation of the left ventricle (P = 0.089) and coronary arteries (P = 0.072) between hybrid IR at Iohexol-300 and DLR at Iohexol-240. Furthermore, application of DLR to the Iohexol-240 significantly improved SNR and CNR; it achieved higher subjective scores compared with hybrid IR at Iohexol-300 (P < 0.001). CONCLUSION: We suggest that using DLR with Iohexol-240 contrast media is preferable to hybrid IR with Iohexol-300 contrast media in coronary CTA.
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Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Humanos , Algoritmos , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste , Angiografia Coronária/métodos , Vasos Coronários , Iohexol , Estudos Prospectivos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodosRESUMO
Background Multiparametric US examination may have potential in the comprehensive evaluation of nonalcoholic fatty liver disease (NAFLD), but multicenter studies are lacking. Purpose To evaluate the diagnostic performance of multiparametric US with the attenuation coefficient (AC) from attenuation imaging (ATI) and liver stiffness (LS) and dispersion slope (DS) from two-dimensional (2D) shear-wave elastography (SWE) in a multicenter study of patients with NAFLD. Materials and Methods This prospective study enrolled consecutive participants between December 2019 and June 2021 with suspected nonalcoholic steatohepatitis (NASH) who were scheduled to undergo liver biopsy in five tertiary hospitals. Before the procedure, all participants underwent US with ATI and 2D SWE according to the study protocol. Multivariable linear regression analyses were performed to determine the significant determinant factors for AC, LS, and DS. Diagnostic performance was decided based on the areas under the receiver operating characteristic curve (AUCs). Results A total of 132 participants (median age, 38 years; IQR, 27-54 years; 69 women) were evaluated. Among the participant characteristics, including pathologic findings, demographic characteristics, body mass index, and serum markers, hepatic steatosis for AC (P < .001), lobular inflammatory activity for DS (P = .007), and both fibrosis (P = .01) and lobular inflammatory activity (P = .04) for LS were significant determinant factors. At histopathologic examination, 53 of the 132 participants (40.2%) had NASH. The risk score system obtained using unweighted sum of scores from AC and DS showed the best diagnostic performance in the detection of NASH (AUC = 0.94; 95% CI: 0.89, 0.98; P < .05 for all), as compared with serum markers or other US parameters alone (AUC ≤ 0.88). Conclusion US attenuation imaging and two-dimensional shear-wave elastography were useful for assessing hepatic steatosis, lobular inflammation, and fibrosis. The risk score system obtained using the attenuation coefficient and dispersion slope showed the best diagnostic performance fo r nonalcoholic steatohepatitis. cris.nih.go.kr no. KCT0004326 © RSNA, 2022 Online supplemental material is available for this article.
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Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Adulto , Estudos Transversais , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos ProspectivosRESUMO
To evaluate the ability of a commercialized deep learning reconstruction technique to depict intracranial vessels on the brain computed tomography angiography and compare the image quality with filtered-back-projection and hybrid iterative reconstruction in terms of objective and subjective measures. Forty-three patients underwent brain computed tomography angiography, and images were reconstructed using three algorithms: filtered-back-projection, hybrid iterative reconstruction, and deep learning reconstruction. The image noise, computed tomography attenuation value, signal-to-noise ratio, and contrast-to-noise ratio were measured in the bilateral cavernous segment of the internal carotid artery, vertebral artery, basilar apex, horizontal segment of the middle cerebral artery and used for the objective assessment of the image quality among the three different reconstructions. The subjective image quality score was significantly higher for the deep learning reconstruction than hybrid iterative reconstruction and filtered-back-projection images. The deep learning reconstruction markedly improved the reduction of blooming artifacts in surgical clips and coiled aneurysms. The deep learning reconstruction method generally improves the image quality of brain computed tomography angiography in terms of objective measurement and subjective grading compared with filtered-back-projection and hybrid iterative reconstruction. Especially, deep learning reconstruction is deemed advantageous for better depiction of small vessels compared to filtered-back projection and hybrid iterative reconstruction.
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Artérias Cerebrais/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Interna/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia por Tomografia Computadorizada/normas , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Estudos Retrospectivos , Artéria Vertebral/diagnóstico por imagem , Adulto JovemRESUMO
OBJECTIVES: To evaluate and compare clinical outcomes of two different radiofrequency ablation (RFA) methods for locally recurred hepatocellular carcinoma (LrHCC) after locoregional treatment. METHODS: Our institutional review board approved this study with a waiver of informed consent. A total of 313 patients previously treated with transarterial chemoembolization (TACE) (n = 167) and RFA (n = 146) with a single LrHCC ≤ 3 cm was included from five tertiary referral hospitals. RFA was done for LrHCCs using either viable tumor alone ablation (VTA) method (VTA: n = 61 in the TACE group and n = 127 in the RFA group) or whole tumor ablation (WTA) method which includes both viable tumor and retained iodized oil or previously ablated zone (WTA: n = 106 in the TACE group and n = 19 in the RFA group). Local tumor progression (LTP)-free survival as well as progression-free survival (PFS) were estimated using the Kaplan-Meier method, and prognostic factors were evaluated using the Cox proportional hazards regression model. RESULTS: In 167 patients with LrHCC who underwent TACE, the 5-year LTP-free survival after RFA was significantly higher with the VTA method than with the WTA method (26.9% vs. 87.8%; p < 0.001; hazard ratio (HR) = 8.53 [4.16-17.5]). The estimated 5-year PFS after RFA for LrHCC after TACE using the VTA method was 5.7%, which was significantly lower than that with the WTA method (26.4%) (p = 0.014; HR = 1.62 [1.10-2.38]). However, in 146 patients with LrHCC after initial RFA, there were no significant differences in cumulative incidence of LTP (p = 0.514) or PFS (p = 0.905) after RFA between the two ablation methods. CONCLUSIONS: For RFA of LrHCC after TACE, the WTA method including both viable tumor and retained iodized oil could significantly lower LTP and improve PFS than VTA. KEY POINTS: ⢠Whole tumor ablation (WTA) could provide significantly better local tumor control for locally recurred HCC (LrHCC) after TACE than viable tumor alone ablation (VTA). ⢠WTA for LrHCC after TACE could also provide significantly better progression-free survival than VTA. ⢠Regarding LrHCC after RFA, VTA would provide a comparable clinical outcome to WTA.
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Técnicas de Ablação/métodos , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Óleo Iodado/farmacologia , Neoplasias Hepáticas/terapia , Recidiva Local de Neoplasia/cirurgia , Tomografia Computadorizada por Raios X/métodos , Idoso , Carcinoma Hepatocelular/diagnóstico , Meios de Contraste/farmacologia , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Intervalo Livre de Progressão , Resultado do TratamentoRESUMO
Purpose To retrospectively evaluate the clinical outcomes of radiofrequency ablation (RFA) for early hypovascular hepatocellular carcinomas (HCCs) and to compare them with those of typical hypervascular HCCs. Materials and Methods This retrospective multicenter study received institutional review board approval, with a waiver of the need to obtain informed consent. A total of 56 patients (male-to-female ratio, 40:16; mean age, 61.8 years; age range, 33-87 years) with pathologically proven early HCCs that did not meet the noninvasive diagnosis criteria and who were initially treated with RFA at one of five university-affiliated hospitals between January 2009 and December 2013 comprised the study group. Thereafter, 240 patients with hypervascular HCCs initially treated with RFA in the same period in a historical cohort were selected as control patients. Overall survival (OS), progression-free survival (PFS), and cumulative incidence of local tumor progression (LTP) were estimated by using Kaplan-Meier analysis and were compared by using the Cox proportional hazard regression model. After the first analysis, propensity score analysis was performed to reduce potential bias. Results Complete ablation was achieved in all 56 patients with early hypovascular HCCs after RFA. The estimated 5-year cumulative incidence of LTP in the 56 patients with early hypovascular HCCs was significantly lower than in the 240 patients with hypervascular HCCs (5.4% for early hypovascular HCCs vs 20.8% for hypervascular HCCs; hazard ratio = 6.57 [95% confidence interval: 1.59, 27.2]; P = .009). After propensity matching, the estimated 5-year cumulative incidence of LTP in patients with early hypovascular HCCs was still significantly lower than that in patients with hypervascular HCCs (5.4% vs 23.0%; P = .025; hazard ratio = 5.71 [95% confidence interval: 1.27, 25.8]). OS was not significantly different between the groups (P = .100). One-year PFS in the 56 patients with early hypovascular HCCs, on the other hand, appeared to be favorable at 92.7%, compared with 79.4% in the 240 patients with hypervascular HCCs, but overall, PFS was not significantly different (P = .066). Conclusion RFA of early hypovascular HCCs provided similar OS and PFS compared with RFA of typical hypervascular HCCs, despite its significantly lower 5-year cumulative incidence of LTP. © RSNA, 2017 Online supplemental material is available for this article.
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Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/estatística & dados numéricos , Neoplasias Hepáticas/cirurgia , Idoso , Carcinoma Hepatocelular/mortalidade , Ablação por Cateter/efeitos adversos , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tempo para o Tratamento , Resultado do TratamentoRESUMO
PURPOSE: To evaluate the incidence of severe bleeding and mortality associated with percutaneous biopsy for hepatic angiosarcoma in a multicenter retrospective cohort. MATERIALS AND METHODS: A retrospective review of 33 patients with biopsy-proven hepatic angiosarcoma (29 male; median age, 57 y; age range, 24-96 y) was performed at seven tertiary academic hospitals between January 1998 and March 2015. The mean maximum tumor size was 5.5 cm (range, 1.7-20 cm). An 18-gauge automated cutting biopsy needle was used with a freehand technique in all patients who underwent ultrasonography-guided percutaneous core needle biopsy on an inpatient basis. The incidences of severe bleeding and procedure-related mortality were evaluated per Society of Interventional Radiology (SIR) guidelines. RESULTS: There was a mean of 2.8 needle passes per patient during the procedure (range, 1-6). The overall incidence of severe bleeding events (SIR grade C/D) was 9.1% (3 of 33). Two patients were managed with blood transfusion, and one patient underwent embolization for bleeding control. No other major complications were encountered. There were no cases of mortality associated with the biopsy. CONCLUSIONS: Severe bleeding was not a frequent complication after percutaneous biopsy for hepatic angiosarcoma. The majority of bleeding complications could be controlled with conservative management.
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Biópsia com Agulha de Grande Calibre/métodos , Hemangiossarcoma/patologia , Biópsia Guiada por Imagem/métodos , Neoplasias Hepáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre/efeitos adversos , Biópsia com Agulha de Grande Calibre/mortalidade , Imagem de Difusão por Ressonância Magnética , Feminino , Pesquisas sobre Atenção à Saúde , Hemorragia/epidemiologia , Hemorragia/mortalidade , Hospitais Universitários , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Biópsia Guiada por Imagem/mortalidade , Imuno-Histoquímica , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Ultrassonografia de Intervenção/efeitos adversos , Ultrassonografia de Intervenção/mortalidade , Adulto JovemRESUMO
BACKGROUND: The aim of this study was to develop an assessment tool for activities of daily living (ADL) from the perspective of patients with Parkinson's disease (PD) and examine the validity and reliability of the assessment. METHODS: A preliminary 45-item questionnaire was developed through intensive interviews with 54 patients with PD and administered to another group of 248 patients with PD. Based on clinical and statistical analyses, 20 ADL-items were selected. The final 20-item questionnaire was examined in the other group of 59 patients with PD. RESULTS: The new ADL questionnaire showed high internal consistency (Cronbach's α, 0.962-0.966) and acceptable test-retest reliability (0.632-0.984). Concurrent validity was shown as a significant positive correlation between the new ADL questionnaire and other ADL or clinical instruments. The Hoehn and Yahr stage showed the highest degree of correlation with the new ADL questionnaire, followed by the other ADL scales (Schwab and England ADL and the ADL subscore of the Unified Parkinson's Disease Rating Scale). Additionally, a regression analysis was conducted with the disease-specific quality of life questionnaire, and the new ADL questionnaire was the most powerful predictor of quality of life among the clinical instruments. CONCLUSIONS: The new ADL questionnaire is a valid tool for assessing ADL from the perspectives of patients with PD.
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Atividades Cotidianas/psicologia , Doença de Parkinson/psicologia , Inquéritos e Questionários , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Psicometria , Qualidade de VidaRESUMO
Successful development of ultra-sensitive molecular imaging nanoprobes for the detection of targeted biological objects is a challenging task. Although magnetic nanoprobes have the potential to perform such a role, the results from probes that are currently available have been far from optimal. Here we used artificial engineering approaches to develop innovative magnetic nanoprobes, through a process that involved the systematic evaluation of the magnetic spin, size and type of spinel metal ferrites. These magnetism-engineered iron oxide (MEIO) nanoprobes, when conjugated with antibodies, showed enhanced magnetic resonance imaging (MRI) sensitivity for the detection of cancer markers compared with probes currently available. Also, we successfully visualized small tumors implanted in a mouse. Such high-performance, nanotechnology-based molecular probes could enhance the ability to visualize other biological events critical to diagnostics and therapeutics.
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Imageamento por Ressonância Magnética/métodos , Magnetismo , Nanopartículas/química , Nanotecnologia/métodos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados , Biomarcadores Tumorais/análise , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Compostos Férricos/química , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias Experimentais/diagnóstico , Neoplasias Experimentais/metabolismo , Receptor ErbB-2/análise , Receptor ErbB-2/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , TrastuzumabRESUMO
This report presents a unique case of an endocervical polyp-mimicking malignancy on pelvic MRI in a 45-year-old female. The MRI depicted a multilocular cystic lesion with an enhancing solid component, raising suspicion for malignancy. However, histopathological examination definitively revealed a benign endocervical polyp. This case highlights the limitations of diagnosing cervical lesions solely on MRI features, emphasizing the potential for benign conditions to mimic malignancy.
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OBJECTIVES: This study aimed to assess the impact of super-resolution deep learning reconstruction (SR-DLR) on coronary CT angiography (CCTA) image quality and blooming artifacts from coronary artery stents in comparison to conventional methods, including hybrid iterative reconstruction (HIR) and deep learning-based reconstruction (DLR). METHODS: A retrospective analysis included 66 CCTA patients from July to November 2022. Major coronary arteries were evaluated for image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Stent sharpness was quantified using 10%-90% edge rise slope (ERS) and 10%-90% edge rise distance (ERD). Qualitative analysis employed a 5-point scoring system to assess overall image quality, image noise, vessel wall, and stent structure. RESULTS: SR-DLR demonstrated significantly lower image noise compared to HIR and DLR. SNR and CNR were notably higher in SR-DLR. Stent ERS was significantly improved in SR-DLR, with mean ERD values of 0.70 ± 0.20 mm for SR-DLR, 1.13 ± 0.28 mm for HIR, and 0.85 ± 0.26 mm for DLR. Qualitatively, SR-DLR scored higher in all categories. CONCLUSIONS: SR-DLR produces images with lower image noise, leading to improved overall image quality, compared with HIR and DLR. SR-DLR is a valuable image reconstruction algorithm for enhancing the spatial resolution and sharpness of coronary artery stents without being constrained by hardware limitations. ADVANCES IN KNOWLEDGE: The overall image quality was significantly higher in SR-DLR, resulting in sharper coronary artery stents compared to HIR and DLR.
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Angiografia por Tomografia Computadorizada , Angiografia Coronária , Aprendizado Profundo , Razão Sinal-Ruído , Stents , Humanos , Estudos Retrospectivos , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Vasos Coronários/diagnóstico por imagem , Artefatos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgiaRESUMO
Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLTGT) is a rare malignant mesenchymal tumor of the gastrointestinal (GI) tract with a high probability of local recurrence and distant metastasis in young adults. To the best of our knowledge, only seven case reports have described the imaging findings of a CCSLTGT originating from in the small intestine in English literatures so far. Therefore, we report the imaging findings of a CCSLTGT that occurred in the small intestine of a 22-year-old female and summarize the imaging findings of the previous reports.
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PURPOSE: This study compared the controlled attenuation parameter (CAP) to attenuation imaging (ATI) in the diagnosis of steatosis and transient elastography (TE) to two-dimensional shear wave elastography (2D-SWE) for the diagnosis of fibrosis in a prospectively constructed nonalcoholic fatty liver disease (NAFLD) patient cohort. METHODS: Participants who underwent TE with CAP were included from a previously constructed NAFLD cohort with multiparametric ultrasound data. The degree of hepatic steatosis and stage of liver fibrosis were assessed. Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUROC) for the grades of steatosis (S1-3) and fibrosis (F0-F4). RESULTS: There were 105 participants. The distribution of hepatic steatosis grades (S0-S3) and liver fibrosis stages (F0-F4) was as follows: S0, n=34; S1, n=41; S2, n=22; S3, n=8; F0, n=63; F1, n=25; F2, n=5; F3, n=7; and F4, n=5. No significant difference was found between CAP and ATI in detecting ≥S1 (AUROC: 0.93 vs. 0.93, P=0.956) or ≥S2 (0.94 vs. 0.94, P=0.769). However, the AUROC of ATI in detecting ≥S3 was significantly higher than that of CAP (0.94 vs. 0.87, P=0.047). Regarding the detection of liver fibrosis, no significant difference was found between TE and 2D-SWE. The AUROCs of TE and 2D-SWE were as follows: ≥F1, 0.94 vs. 0.89 (P=0.107); ≥F2, 0.89 vs. 0.90 (P=0.644); ≥F3, 0.91 vs. 0.90 (P=0.703); and ≥F4, 0.88 vs. 0.92 (P=0.209). CONCLUSION: 2D-SWE and TE showed comparable diagnostic performance in assessing liver fibrosis, and ATI provided significantly better performance in detecting ≥S3 steatosis than CAP.
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PURPOSE: To assess factors affecting tumor visibility on planning ultrasound (US) for percutaneous radiofrequency (RF) ablation to treat small hepatocellular carcinomas (HCCs) primarily detected on computed tomography (CT) or magnetic resonance (MR) imaging. MATERIALS AND METHODS: Patients referred for planning US for percutaneous RF ablation between September 2008 and June 2009 were prospectively enrolled from nine institutions in Korea. The first small (≤ 3 cm) single HCC or new single HCC after treatment was included. The study enrolled 898 patients (684 men and 214 women, age range 32-86 years). HCCs that were invisible on planning US were compared with visible HCCs with respect to tumor size, distance between the tumor and the diaphragm, subcapsular location, etiology of liver disease, liver cirrhosis, macronodular cirrhosis on US, ascites, Child-Pugh class, serum alpha fetoprotein (AFP) level, body mass index (BMI), previous treatments for HCC, previous chemoembolization treatments for HCC, institutions, and experience of radiologists. RESULTS: Among 898 HCCs, 671 (74.7%) were visible on the planning US. In multivariate analysis, tumor size, distance between the tumor and the diaphragm, liver cirrhosis, and macronodular cirrhosis were statistically significant factors affecting US detection (each P < .05). CONCLUSIONS: Smaller tumors, subphrenic location of the tumor, liver cirrhosis, and macronodular cirrhosis were independent predictors of invisible tumors on planning US.
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Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Tomografia Computadorizada Multidetectores , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Carcinoma Hepatocelular/patologia , Distribuição de Qui-Quadrado , Competência Clínica , Meios de Contraste , Feminino , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Estudos Prospectivos , República da Coreia , Índice de Gravidade de Doença , Carga Tumoral , alfa-Fetoproteínas/análiseRESUMO
OBJECTIVE: This study aimed to investigate whether a deep learning reconstruction (DLR) method improves the image quality, stent evaluation, and visibility of the valve apparatus in coronary computed tomography angiography (CCTA) when compared with filtered back projection (FBP) and hybrid iterative reconstruction (IR) methods. MATERIALS AND METHODS: CCTA images of 51 patients (mean age ± standard deviation [SD], 63.9 ± 9.8 years, 36 male) who underwent examination at a single institution were reconstructed using DLR, FBP, and hybrid IR methods and reviewed. CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and stent evaluation, including 10%-90% edge rise slope (ERS) and 10%-90% edge rise distance (ERD), were measured. Quantitative data are summarized as the mean ± SD. The subjective visual scores (1 for worst -5 for best) of the images were obtained for the following: overall image quality, image noise, and appearance of stent, vessel, and aortic and tricuspid valve apparatus (annulus, leaflets, papillary muscles, and chordae tendineae). These parameters were compared between the DLR, FBP, and hybrid IR methods. RESULTS: DLR provided higher Hounsfield unit (HU) values in the aorta and similar attenuation in the fat and muscle compared with FBP and hybrid IR. The image noise in HU was significantly lower in DLR (12.6 ± 2.2) than in hybrid IR (24.2 ± 3.0) and FBP (54.2 ± 9.5) (p < 0.001). The SNR and CNR were significantly higher in the DLR group than in the FBP and hybrid IR groups (p < 0.001). In the coronary stent, the mean value of ERS was significantly higher in DLR (1260.4 ± 242.5 HU/mm) than that of FBP (801.9 ± 170.7 HU/mm) and hybrid IR (641.9 ± 112.0 HU/mm). The mean value of ERD was measured as 0.8 ± 0.1 mm for DLR while it was 1.1 ± 0.2 mm for FBP and 1.1 ± 0.2 mm for hybrid IR. The subjective visual scores were higher in the DLR than in the images reconstructed with FBP and hybrid IR. CONCLUSION: DLR reconstruction provided better images than FBP and hybrid IR reconstruction.
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Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Humanos , Masculino , Angiografia por Tomografia Computadorizada/métodos , Vasos Coronários/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Stents , Algoritmos , Doses de Radiação , Angiografia Coronária/métodosRESUMO
Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) have been reported to exhibit immature embryonic or fetal cardiomyocyte-like phenotypes. To enhance the maturation of hESC-CMs, we identified a natural steroidal alkaloid, tomatidine, as a new substance that stimulates the maturation of hESC-CMs. Treatment of human embryonic stem cells with tomatidine during cardiomyocyte differentiation stimulated the expression of several cardiomyocyte-specific markers and increased the density of T-tubules. Furthermore, tomatidine treatment augmented the number and size of mitochondria and enhanced the formation of mitochondrial lamellar cristae. Tomatidine treatment stimulated mitochondrial functions, including mitochondrial membrane potential, oxidative phosphorylation, and ATP production, in hESC-CMs. Tomatidine-treated hESC-CMs were more sensitive to doxorubicin-induced cardiotoxicity than the control cells. In conclusion, the present study suggests that tomatidine promotes the differentiation of stem cells to adult cardiomyocytes by accelerating mitochondrial biogenesis and maturation and that tomatidine-treated mature hESC-CMs can be used for cardiotoxicity screening and cardiac disease modeling.
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Células-Tronco Embrionárias Humanas , Cardiotoxicidade/etiologia , Diferenciação Celular , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Mitocôndrias , Miócitos Cardíacos/metabolismo , Tomatina/análogos & derivadosRESUMO
We present a colloidal route for the synthesis of ultrathin ZrS(2) (UT-ZrS(2)) nanodiscs that are ~1.6 nm thick and consist of approximately two unit cells of S-Zr-S. The lateral size of the discs can be tuned to 20, 35, or 60 nm while their thickness is kept constant. Under the appropriate conditions, these individual discs can self-assemble into face-to-face-stacked structures containing multiple discs. Because the S-Zr-S layers within individual discs are held together by weak van der Waals interactions, each UT-ZrS(2) disc provides spaces that can serve as host sites for intercalation. When we tested UT-ZrS(2) discs as anodic materials for Li(+) intercalation, they showed excellent nanoscale size effects, enhancing the discharge capacity by 230% and greatly improving the stability in comparison with bulk ZrS(2). The nanoscale size effect was especially prominent for their performance in fast charging/discharging cycles, where an 88% average recovery of reversible capacity was observed for UT-ZrS(2) discs with a lateral diameter of 20 nm. The nanoscale thickness and lateral size of UT-ZrS(2) discs are critical for fast and reliable intercalation cycling because those dimensions both increase the surface area and provide open edges that enhance the diffusion kinetics for guest molecules.
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Regioselective chemical reactions and structural transformations of two-dimensional (2D) layered transition-metal chalcogenide (TMC) nanocrystals are described. Upon exposure of 2D TiS(2) nanodiscs to a chemical stimulus, such as Cu ion, selective chemical reaction begins to occur at the peripheral edges. This edge reaction is followed by ion diffusion, which is facilitated by interlayer nanochannels and leads to the formation of a heteroepitaxial TiS(2)-Cu(2)S intermediate. These processes eventually result in the generation of a single-crystalline, double-convex toroidal Cu(2)S nanostructure. Such 2D regioselective chemical reactions also take place when other ionic reactants are used. The observations made and chemical principles uncovered in this effort indicate that a general approach exists for building various toroidal nanocrystals of substances such as Ag(2)S, MnS, and CdS.
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Xanthogranulomatous inflammation (XGI) is a rare, idiopathic process in which lipid-laden histiocytes are deposited at various locations in the body. Although XGI has been reported to occur in various organs such as the gallbladder, kidney, bone, stomach, colon, appendix, lymph nodes, urachus, and urinary bladder and in soft tissues, xanthogranulomatous pancreatitis (XGP) is extremely rare. Herein, we report a case of XGP occurring in a 70-yr-old woman, who presented with abdominal pain for several months. On physical examination, mild epigastric tenderness was noted. Abdomen CT scan revealed a low attenuated mass in uncinate process of pancreas, suggesting malignant lesion. Whipple's operation was performed and the final pathologic diagnosis was XGP. The patient's post-operative course was uneventful, and no recurrence was found within 7 months of the operation. When a pancreatic mass does not show clinico-radiological features typical of common pancreatic neoplasms, XGP should be considered for a differential diagnosis.
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Granuloma/diagnóstico , Pancreatite/diagnóstico , Xantomatose/diagnóstico , Idoso , Diagnóstico Diferencial , Duodeno/cirurgia , Feminino , Granuloma/complicações , Granuloma/patologia , Humanos , Pâncreas/cirurgia , Neoplasias Pancreáticas/patologia , Pancreatite/complicações , Pancreatite/patologia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Xantomatose/complicações , Xantomatose/patologiaRESUMO
Renal epithelioid angiomyolipoma (EAML) is a rare variant of angiomyolipoma (AML), with a prominent epithelioid component. EAML usually presents as a large heterogeneous soft tissue lesion with intratumoral hemorrhage and variable necrosis or cystic changes. We present a case of multiloculated cystic renal EAML mimicking renal cell carcinoma in a 64-year-old female. Intracystic massive hemorrhage, hyperattenuating wall and septa on an unenhanced study, and enlarged intratumoral vessels can be helpful imaging features for distinguishing renal EAML from renal cell carcinoma.
RESUMO
Immunoglobulin G4 (IgG4)-related disease is a systemic disease characterized by dense lymphoplasmacytic infiltrates with abundant IgG4-positive plasma cells and fibroblast proliferation. The retroperitoneal involvement of IgG4-related disease usually appears as a soft-tissue mass covering the abdominal aorta or entrapping the ureters, resulting in hydronephrosis. Here, we present a case of IgG4-related disease with retroperitoneal involvement in a 75-year-old woman with an unusual manifestation. A preoperative computed tomography (CT) scan revealed an irregular infiltrative retroperitoneal mass invading the normal anatomic barriers, raising the suspicion of malignancy or inflammation. Contrast-enhanced CT revealed a homogeneous progressive enhancement of the mass.