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1.
Acta Radiol ; 64(3): 1007-1017, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35979586

ABSTRACT

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.


Subject(s)
Computed Tomography Angiography , Deep Learning , Humans , Algorithms , Computed Tomography Angiography/methods , Contrast Media , Coronary Angiography/methods , Coronary Vessels , Iohexol , Prospective Studies , Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods
2.
Radiology ; 305(1): 118-126, 2022 10.
Article in English | MEDLINE | ID: mdl-35727151

ABSTRACT

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.


Subject(s)
Elasticity Imaging Techniques , Non-alcoholic Fatty Liver Disease , Adult , Cross-Sectional Studies , Elasticity Imaging Techniques/methods , Female , Humans , Liver/diagnostic imaging , Liver/pathology , Liver Cirrhosis/pathology , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Non-alcoholic Fatty Liver Disease/pathology , Prospective Studies
3.
J Integr Neurosci ; 20(4): 967-976, 2021 Dec 30.
Article in English | MEDLINE | ID: mdl-34997719

ABSTRACT

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.


Subject(s)
Cerebral Arteries/diagnostic imaging , Computed Tomography Angiography , Deep Learning , Image Processing, Computer-Assisted , Adolescent , Adult , Aged , Aged, 80 and over , Carotid Artery, Internal/diagnostic imaging , Computed Tomography Angiography/methods , Computed Tomography Angiography/standards , Female , Humans , Image Processing, Computer-Assisted/methods , Image Processing, Computer-Assisted/standards , Male , Middle Aged , Middle Cerebral Artery/diagnostic imaging , Retrospective Studies , Vertebral Artery/diagnostic imaging , Young Adult
4.
Eur Radiol ; 29(9): 5052-5062, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30770968

ABSTRACT

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.


Subject(s)
Ablation Techniques/methods , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Iodized Oil/pharmacology , Liver Neoplasms/therapy , Neoplasm Recurrence, Local/surgery , Tomography, X-Ray Computed/methods , Aged , Carcinoma, Hepatocellular/diagnosis , Contrast Media/pharmacology , Female , Humans , Liver Neoplasms/diagnosis , Male , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Progression-Free Survival , Treatment Outcome
5.
Radiology ; 286(1): 338-349, 2018 01.
Article in English | MEDLINE | ID: mdl-28981400

ABSTRACT

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.


Subject(s)
Carcinoma, Hepatocellular/surgery , Catheter Ablation/statistics & numerical data , Liver Neoplasms/surgery , Aged , Carcinoma, Hepatocellular/mortality , Catheter Ablation/adverse effects , Humans , Liver Neoplasms/mortality , Male , Middle Aged , Retrospective Studies , Time-to-Treatment , Treatment Outcome
6.
J Vasc Interv Radiol ; 27(6): 846-51, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27080009

ABSTRACT

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.


Subject(s)
Biopsy, Large-Core Needle/methods , Hemangiosarcoma/pathology , Image-Guided Biopsy/methods , Liver Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Biopsy, Large-Core Needle/adverse effects , Biopsy, Large-Core Needle/mortality , Diffusion Magnetic Resonance Imaging , Female , Health Care Surveys , Hemorrhage/epidemiology , Hemorrhage/mortality , Hospitals, University , Humans , Image-Guided Biopsy/adverse effects , Image-Guided Biopsy/mortality , Immunohistochemistry , Incidence , Logistic Models , Male , Middle Aged , Multivariate Analysis , Odds Ratio , Predictive Value of Tests , Republic of Korea/epidemiology , Retrospective Studies , Risk Factors , Severity of Illness Index , Ultrasonography, Interventional/adverse effects , Ultrasonography, Interventional/mortality , Young Adult
7.
BMC Neurol ; 16: 73, 2016 May 21.
Article in English | MEDLINE | ID: mdl-27206611

ABSTRACT

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.


Subject(s)
Activities of Daily Living/psychology , Parkinson Disease/psychology , Surveys and Questionnaires , Aged , Cross-Sectional Studies , Female , Humans , Male , Predictive Value of Tests , Psychometrics , Quality of Life
8.
Nat Med ; 13(1): 95-9, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17187073

ABSTRACT

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.


Subject(s)
Magnetic Resonance Imaging/methods , Magnetics , Nanoparticles/chemistry , Nanotechnology/methods , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal, Humanized , Biomarkers, Tumor/analysis , Cell Line , Cell Line, Tumor , Female , Ferric Compounds/chemistry , HeLa Cells , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms, Experimental/diagnosis , Neoplasms, Experimental/metabolism , Receptor, ErbB-2/analysis , Receptor, ErbB-2/immunology , Reproducibility of Results , Sensitivity and Specificity , Trastuzumab
9.
Br J Radiol ; 97(1159): 1286-1294, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38733576

ABSTRACT

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.


Subject(s)
Computed Tomography Angiography , Coronary Angiography , Deep Learning , Signal-To-Noise Ratio , Stents , Humans , Retrospective Studies , Computed Tomography Angiography/methods , Coronary Angiography/methods , Male , Female , Middle Aged , Aged , Coronary Vessels/diagnostic imaging , Artifacts , Radiographic Image Interpretation, Computer-Assisted/methods , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/surgery
10.
J Korean Soc Radiol ; 84(5): 1169-1175, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37869114

ABSTRACT

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.

11.
Ultrasonography ; 42(3): 421-431, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37076274

ABSTRACT

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.

12.
J Vasc Interv Radiol ; 23(5): 627-34, 2012 May.
Article in English | MEDLINE | ID: mdl-22387030

ABSTRACT

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.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/surgery , Catheter Ablation , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Magnetic Resonance Imaging , Multidetector Computed Tomography , Ultrasonography, Interventional , Adult , Aged , Aged, 80 and over , Body Mass Index , Carcinoma, Hepatocellular/pathology , Chi-Square Distribution , Clinical Competence , Contrast Media , Female , Humans , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/pathology , Liver Cirrhosis/surgery , Liver Neoplasms/pathology , Logistic Models , Male , Middle Aged , Multivariate Analysis , Predictive Value of Tests , Prospective Studies , Republic of Korea , Severity of Illness Index , Tumor Burden , alpha-Fetoproteins/analysis
13.
Korean J Radiol ; 23(11): 1044-1054, 2022 11.
Article in English | MEDLINE | ID: mdl-36196766

ABSTRACT

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.


Subject(s)
Computed Tomography Angiography , Deep Learning , Humans , Male , Computed Tomography Angiography/methods , Coronary Vessels/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Stents , Algorithms , Radiation Dosage , Coronary Angiography/methods
14.
Exp Mol Med ; 54(4): 493-502, 2022 04.
Article in English | MEDLINE | ID: mdl-35379934

ABSTRACT

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.


Subject(s)
Human Embryonic Stem Cells , Cardiotoxicity/etiology , Cell Differentiation , Human Embryonic Stem Cells/metabolism , Humans , Mitochondria , Myocytes, Cardiac/metabolism , Tomatine/analogs & derivatives
15.
J Am Chem Soc ; 133(37): 14500-3, 2011 Sep 21.
Article in English | MEDLINE | ID: mdl-21875086

ABSTRACT

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.

16.
J Am Chem Soc ; 133(20): 7636-9, 2011 May 25.
Article in English | MEDLINE | ID: mdl-21539379

ABSTRACT

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.

17.
J Korean Med Sci ; 26(4): 583-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21468270

ABSTRACT

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.


Subject(s)
Granuloma/diagnosis , Pancreatitis/diagnosis , Xanthomatosis/diagnosis , Aged , Diagnosis, Differential , Duodenum/surgery , Female , Granuloma/complications , Granuloma/pathology , Humans , Pancreas/surgery , Pancreatic Neoplasms/pathology , Pancreatitis/complications , Pancreatitis/pathology , Positron-Emission Tomography , Tomography, X-Ray Computed , Xanthomatosis/complications , Xanthomatosis/pathology
18.
Taehan Yongsang Uihakhoe Chi ; 82(5): 1292-1296, 2021 Sep.
Article in English | MEDLINE | ID: mdl-36238387

ABSTRACT

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.

19.
Taehan Yongsang Uihakhoe Chi ; 82(2): 487-492, 2021 Mar.
Article in English | MEDLINE | ID: mdl-36238745

ABSTRACT

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.

20.
Circ J ; 74(2): 284-8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20032562

ABSTRACT

BACKGROUND: Minimally invasive robot-assisted cardiac surgery is generally performed nowadays. To avoid the interference of a superior vena cava (SVC) cannula during surgery, it should be inserted before the operation. The position of this cannula is very important because it can cause poor venous drainage during operation. The proper position of the SVC cannula was investigated in the present study. METHODS AND RESULTS: The position of the SVC cannula using the transesophageal echocardiography (TEE) and chest X-ray in 45 patients was ascertained. The distances from the SVC cannula tip to the carina, sternal end of the right clavicle and the lower margin of the T4 vertebral body on chest X-rays were measured. The mean depth of the SVC cannula was 142.0+/-11.6 mm. The correlation coefficients of cannula depth with sex, weight and height were 0.519, 0.399 and 0.382, respectively. CONCLUSIONS: The appropriate depth of an SVC cannula has weakly positive relationships with sex, weight and height. The results of the present study suggest that chest X-rays might be necessary to confirm the appropriate location of the cannula and that TEE might be the method of choice for correct positioning of the SVC cannula in minimally invasive robot-assisted cardiac surgery.


Subject(s)
Cardiac Surgical Procedures , Catheterization, Central Venous , Robotics , Surgery, Computer-Assisted , Vena Cava, Superior , Adult , Catheterization, Central Venous/instrumentation , Echocardiography, Transesophageal , Equipment Design , Female , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures , Punctures , Radiography, Thoracic , Vena Cava, Superior/diagnostic imaging
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