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1.
Artigo em Inglês | MEDLINE | ID: mdl-38670928

RESUMO

Spin-to-charge conversion at the interface between magnetic materials and transition metal dichalcogenides has drawn great interest in the research efforts to develop fast and ultralow power consumption devices for spintronic applications. Here, we report room temperature observations of spin-to-charge conversion arising from the interface of Ni80Fe20 (Py) and molybdenum disulfide (MoS2). This phenomenon can be characterized by the inverse Edelstein effect length (λIEE), which is enhanced with decreasing MoS2 thicknesses, demonstrating the dominant role of spin-orbital coupling (SOC) in MoS2. The spin-to-charge conversion can be significantly improved by inserting a Cu interlayer between Py and MoS2, suggesting that the Cu interlayer can prevent magnetic proximity effect from the Py layer and protect the SOC on the MoS2 surface from exchange interactions with Py. Furthermore, the Cu-MoS2 interface can enhance the spin current and improve electronic transport. Our results suggest that tailoring the interface of magnetic heterostructures provides an alternative strategy for the development of spintronic devices to achieve higher spin-to-charge conversion efficiencies.

2.
Eur J Radiol ; 175: 111439, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38547743

RESUMO

OBJECTIVE: To evaluate the value of dynamic contrast-enhanced ultrasound (DCE-US) analysis in early prediction of tumor response to systemic treatment in patients with intrahepatic cholangiocarcinoma (ICC). PATIENTS & METHODS: In this retrospective study, patients diagnosed with ICC by core needle biopsy and histopathological results were included. All patients were diagnosed as advanced stages (stage III/IV) by the 8th edition of the American Joint Committee on Cancer (AJCC)/International Union Against Cancer (UICC) TNM staging system. Liver contrast-enhanced ultrasound (CEUS) examination, DCE-US analysis, CT/MRI, and blood tests were performed in all patients before and 2 months after systemic treatment. CEUS procedure was performed using an ultrasound system (ACUSON Sequoia; Siemens Medical Solutions, Germany) equipped with a 5C1 MHz convex array transducer. Time-intensity curves (TIC) and quantitative parameters were created with VueBox software. According to one-year results of the modified Response Evaluation Criteria in Solid Tumors (m-RECIST) based on CT/MRI, patients were divided into the responder group (RG) and the non-responder group (NRG). Before and 2 months after systemic therapy, the DCE-US perfusion parameters was compared using the paired-sample t test and the Wilcoxon test. RESULTS: From September 2020 to December 2021, a total of 24 patients diagnosed with advanced ICC were included (11 males, 13 females, mean age 59.4 ± 1.8 years). According to the one year of m-RECIST results, 17 cases (70.8 %) were classified as non-responders by the final m-RECIST criteria, while 7 cases (19.2 %) were responders. Comparing before and 2 months after therapy, the RG took longer time to reach peak intensity, and the peak intensity of TIC was lower. While the TICs of NRG revealed faster enhancement after therapy. Among all DCE-US quantitative parameters, PE (peak enhancement), WiR (wash-in rate), WiPI (wash-in perfusion index) and WoR (wash-out rate) reduced significantly following 2 months of systemic therapy in RG (P < 0.05). Comparing to RG, PE and WiPI decreased slightly 2 months after therapy in NRG (P < 0.05). CONCLUSIONS: The DCE-US analysis with quantitative parameters has the potential value to make early and quantitative evaluation of treatment response to systemic therapy in ICC patients.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Meios de Contraste , Ultrassonografia , Humanos , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/tratamento farmacológico , Estudos Retrospectivos , Ultrassonografia/métodos , Idoso , Resultado do Tratamento , Aumento da Imagem/métodos
3.
Clin Hemorheol Microcirc ; 86(3): 313-326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37927251

RESUMO

OBJECTIVES: To evaluate the efficacy of the radiomics model based on preoperative B-mode ultrasound (BMUS) and shear wave elastography (SWE) for predicting the occurrence of clinically relevant-postoperative pancreatic fistula (CR-POPF). METHODS: Patients who were scheduled to undergo pancreatectomy were prospectively enrolled and received ultrasound assessment within one week before surgery. The risk factors of POPF (grades B and grades C) were analyzed. Preoperative BMUS images, SWE values of pancreatic lesions and surrounding parenchyma were used to build preoperative prediction radiomics models. Radiomic signatures were extracted and constructed using a minimal Redundancy Maximal Relevance (mRMR) algorithm and an L1 penalized logistic regression. A combined model was built using multivariate regression which incorporated radiomics signatures and clinical data. RESULTS: From January 2020 to November 2021, a total of 147 patients (85 distal pancreatectomies and 62 pancreaticoduodenectomies) were enrolled. During the three-week follow-up after pancreatectomy, the incidence rates of grade B/C POPF were 28.6% (42/147). Radiomic signatures constructed from BMUS of pancreas parenchymal regions (panRS) achieved an area under the receiver operating characteristic curve (AUC) of 0.75, accuracy of 68.7%, sensitivity of 85.7 %, and specificity of 61.9 % in preoperative noninvasive prediction of CR-POPF. The AUC of the radiomics model increased to 0.81 when panRS was used for the prediction of CR-POPF after pancreaticoduodenectomy. CONCLUSIONS: Radiomics model based on ultrasound images was potentially useful for predicting CR-POPF. Patients with high-risk factors should be closely monitored when postoperation.


Assuntos
Pancreatectomia , Fístula Pancreática , Humanos , Pancreatectomia/efeitos adversos , Fístula Pancreática/etiologia , Fístula Pancreática/complicações , Radiômica , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Fatores de Risco , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/patologia , Estudos Retrospectivos
4.
Ultrasound Med Biol ; 50(1): 39-46, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37778901

RESUMO

OBJECTIVE: The aim of the work described here was to evaluate the impact of hepatocellular carcinoma (HCC) tumor size on Sonazoid contrast-enhanced ultrasound (CEUS) enhancement features, especially in tumors with diameters ≤30 mm and <10 mm. METHODS: In this retrospective study, we included patients with histopathologically confirmed HCC lesions and divided them into three groups on the basis of tumor size. All patients underwent Sonazoid-enhanced CEUS examinations before surgery. B-mode ultrasound (BMUS) features and CEUS enhancement patterns were evaluated according to current World Federation for Ultrasound in Medicine and Biology Guidelines criteria. The χ2- and Student t-tests were used to compare differences between groups. RESULTS: We included 132 patients with histopathologically confirmed HCC lesions from November 2020 to September 2022. On the basis of tumor size, patients were divided into group 1 (<10 mm, n = 5), group 2 (10-30 mm, n = 54) and group 3 (>30 mm, n = 73). On BMUS, most HCCs appeared heterogeneous but predominantly hypo-echoic (61.4%, 81/132) with ill-defined margins and irregular shapes. Meanwhile, iso-echoic features were more common in small HCCs ≤30 mm (15.3%, 9/59), but a mixed hyper- and hypo-echoic appearance was more common in HCCs >30 mm (17.8%, 13/73) (p = 0.003). On Sonazoid-enhanced CEUS, all HCCs presented arterial phase hyperenhancement (APHE) (100.0%, 132/132). Most HCCs >30 mm exhibited heterogeneous hyperenhancement (86.3%, 63/73), whereas nearly one-third of small HCCs ≤30 mm exhibited homogeneous hyperenhancement (35.6%, 21/59) (p = 0.003). In the portal venous phase, there was a significantly higher proportion of washout in HCCs >30 mm (84.9%, 62/73) than in small HCCs ≤30 mm (64.4%, 38/59) (p = 0.006). During the Kupffer phase, 11 additional hypo-enhanced lesions (mean size: 14.1 ± 4.1 mm, iso-echoic on BMUS), which were also suspected to be HCC lesions, were detected in 5 patients with small HCCs ≤30 mm and 4 patients with HCCs >30 mm. All 5 cases of HCCs <10 mm exhibited APHE and late washout (>60 s). The majority (3/5, 60%) exhibited washout in the portal venous phase (70, 74 and 75 s), one case did so in the late phase (125 s) and another in the Kupffer phase (420 s). CONCLUSION: Tumor size had a significant impact on the washout features of HCC lesions on Sonazoid-enhanced CEUS. Small HCC lesions ≤30 mm had a higher proportion of relatively late washout in comparison to larger lesions. Sonazoid-enhanced CEUS might be helpful in the detection and characterization of HCC lesions <10 mm.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Meios de Contraste , Ultrassonografia
5.
Clin Hemorheol Microcirc ; 85(4): 421-431, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37718786

RESUMO

PURPOSES: To evaluate the application of contrast enhanced ultrasound (CEUS) in preoperatively differential diagnosis between pancreatic solid pseudopapillary tumors (SPTs) and pancreatic neuroendocrine tumors (pNETs). PATIENTS AND METHODS: This retrospective study was approved by Institutional Review Board. Patients with surgical resection and histopathological diagnosis as SPTs and pNETs were included. All patients underwent B mode ultrasound (BMUS) and CEUS examinations within one week before surgical operation. On BMUS, the size, location, echogenicity, calcification, and margin of lesions were observed and recorded. On CEUS imaging, enhancement patterns, and enhancement degrees were recorded and analyzed. An independent t-test or Mann-Whitney U test was used for comparison between continuous variables. Chi-square test was used to compare the CEUS patterns. RESULTS: From February 2017 to Dec 2022, patients diagnosed as SPTs (n = 39) and pNETs (n = 48) were retrospectively included. On BMUS, anechoic cystic changes (19/39, 48.72%) and hyperechoic calcification (14/39, 35.90%) are more commonly detected in SPTs (P = 0.000). On CEUS imaging, the majority of SPTs (27/39, 69.23%) showed hypo-enhancement in the arterial phase, while most of the pNETs (36/48, 75.00%) showed hyper- or iso-enhancement in the arterial phase (P = 0.000). In the venous phase, most of the SPTs (32/39, 82.05%) showed hypo-enhancement, while over half of pNETs (29/48, 60.42%) showed hyper- or iso-enhancement compared to pancreatic parenchyma (P = 0.001). CONCLUSIONS: CEUS is a valuable and non-invasive imaging method to make preoperatively differential diagnoses between SPTs and pNETs.


Assuntos
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Diagnóstico Diferencial , Estudos Retrospectivos , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Meios de Contraste , Neoplasias Pancreáticas/cirurgia , Ultrassonografia
6.
Br J Radiol ; 96(1149): 20220783, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37393539

RESUMO

OBJECTIVE: We aimed to investigate whether the radiomics analysis based on B-mode ultrasound (BMUS) images could predict histopathological tumor grades in pancreatic neuroendocrine tumors (pNETs). METHODS: A total of 64 patients with surgery and histopathologically confirmed pNETs were retrospectively included (34 male and 30 female, mean age 52.4 ± 12.2 years). Patients were divided into training cohort (n = 44) and validation cohort (n = 20). All pNETs were classified into Grade 1 (G1), Grade 2 (G2), and Grade 3 (G3) tumors based on the Ki-67 proliferation index and the mitotic activity according to WHO 2017 criteria. Maximum relevance minimum redundancy, least absolute shrinkage and selection operator were used for feature selection. Receiver operating characteristic curve analysis was used to evaluate the model performance. RESULTS: Finally, 18 G1 pNETs, 35 G2 pNETs, and 11 G3 pNETs patients were included. The radiomic score derived from BMUS images to predict G2/G3 from G1 displayed a good performance with an area under the receiver operating characteristic curve of 0.844 in the training cohort, and 0.833 in the testing cohort. The radiomic score achieved an accuracy of 81.8% in the training cohort and 80.0% in the testing cohort, a sensitivity of 0.750 and 0.786, a specificity of 0.833 and 0.833 in the training/testing cohorts. Clinical benefit of the score also exhibited superior usefulness of the radiomic score, as shown by the decision curve analysis. CONCLUSIONS: Radiomic data constructed from BMUS images have the potential for predicting histopathological tumor grades in patients with pNETs. ADVANCES IN KNOWLEDGE: The radiomic model constructed from BMUS images has the potential for predicting histopathological tumor grades and Ki-67 proliferation indexes in patients with pNETs.


Assuntos
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Estudos Retrospectivos , Antígeno Ki-67 , Gradação de Tumores , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia
7.
J Ultrason ; 23(93): e45-e52, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37520747

RESUMO

Aim: To investigate the diagnostic value of resistance index (RI) in differentiating focal liver lesions. Patients and methods: In this retrospective study, a total of 576 patients with histologically confirmed focal liver lesions were included. Each patient underwent B-mode ultrasound examination and color Doppler ultrasound examination. The RI values of different focal liver lesions were recorded and compared. Results: The mean RI value of benign lesions was significantly lower than that of malignant lesions (0.54 ± 0.10 vs. 0.71 ± 0.12) (p <0.05). In malignant lesions, the RI value of intrahepatic cholangiocarcinoma was significantly lower than that of hepatocellular carcinoma lesions. Furthermore, in hepatocellular carcinoma lesions, the RI of large lesions (group 4: >10 cm) was significantly lower than that of small lesions (group 1: ≤2 cm, group 2: 2-5 cm) (p <0.05). Taken RI of 0.615 as a cutoff value to differentiate malignant and benign lesions, the sensitivity, specificity, positive predictive value and negative predictive value were 82.80%, 81.00%, 81.34% and 82.48%, respectively. Conclusion: Color Doppler ultrasound examination is a valuable imaging method in detecting blood flow signal within liver lesions. The RI parameter should be helpful in differentiating malignant and benign liver tumors.

8.
Eur Radiol ; 33(11): 7866-7876, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37368114

RESUMO

OBJECTIVES: The aim of this study was to modify recognized clinically relevant post-operative pancreatic fistula (CR-POPF) risk evaluation models with quantitative ultrasound shear wave elastography (SWE) values and identified clinical parameters to improve the objectivity and reliability of the prediction. METHODS: Two prospective, successive cohorts were initially designed for the establishment of CR-POPF risk evaluation model and the internal validation. Patients who scheduled to receive pancreatectomy were enrolled. Virtual touch tissue imaging and quantification (VTIQ)-SWE was used to quantify pancreatic stiffness. CR-POPF was diagnosed according to 2016 International Study Group of Pancreatic Fistula standard. Recognized peri-operative risk factors of CR-POPF were analyzed, and the independent variables selected from multivariate logistic regression were used to build the prediction model. RESULTS: Finally, the CR-POPF risk evaluation model was built in a group of 143 patients (cohort 1). CR-POPF occurred in 52/143 (36%) patients. Constructed from SWE values and other identified clinical parameters, the model achieved an area under the receiver operating characteristic curve of 0.866, with sensitivity, specificity, and likelihood ratio of 71.2%, 80.2%, and 3.597 in predicting CR-POPF. Decision curve of modified model revealed a better clinical benefit compared to the previous clinical prediction models. The models were then examined via internal validation in a separate collection of 72 patients (cohort 2). CONCLUSIONS: Risk evaluation model based on SWE and clinical parameters is a potential non-invasive way to pre-operatively, objectively predict CR-POPF after pancreatectomy. CLINICAL RELEVANCE STATEMENT: Our modified model based on ultrasound shear wave elastography may provide an easy access in pre-operative and quantitative evaluating the risk of CR-POPF following pancreatectomy and improve the objectivity and reliability of the prediction compared to previous clinical models. KEY POINTS: • Modified prediction model based on ultrasound shear wave elastography (SWE) provides an easy access for clinicians to pre-operatively, objectively evaluate the risk of clinically relevant post-operative pancreatic fistula (CR-POPF) following pancreatectomy. • Prospective study with validation showed that the modified model provides better diagnostic efficacy and clinical benefits compared to previous clinical models in predicting CR-POPF. • Peri-operative management of CR-POPF high-risk patients becomes more possible.


Assuntos
Técnicas de Imagem por Elasticidade , Pancreatectomia , Humanos , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Estudos Prospectivos , Técnicas de Imagem por Elasticidade/métodos , Reprodutibilidade dos Testes , Fatores de Risco , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Pancreaticoduodenectomia/efeitos adversos , Estudos Retrospectivos
9.
Ultrasound Med Biol ; 49(8): 1780-1788, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156676

RESUMO

OBJECTIVE: The aim of the work described here was to investigate the value of dynamic contrast enhanced ultrasound (DCE-US) and quantitative analysis in pre-operative differential diagnosis of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) in non-cirrhotic liver. METHODS: In this retrospective study, patients with histopathologically proven ICC and HCC lesions in non-cirrhotic liver were included. All patients underwent contrast-enhanced ultrasound (CEUS) examinations with an Acuson Sequoia unit (Siemens Healthineers, Mountain View, CA, USA) unit or LOGIQ E20 (GE Healthcare, Milwaukee, WI, USA) within 1 wk before surgery. SonoVue (Bracco, Milan, Italy) was used as the contrast agent. B-mode ultrasound (BMUS) features and CEUS enhancement patterns were analyzed. DCE-US analysis was performed by VueBox software (Bracco). Two regions of interest (ROIs) were set in the center of the focal liver lesions and their surrounding liver parenchyma. Time-intensity curves (TICs) were generated, and quantitative perfusion parameters were obtained and compared between the ICC and HCC groups using the Student t-test or Mann-Whitney U-test. RESULTS: From November 2020 to February 2022, patients with histopathologically confirmed ICC (n = 30) and HCC (n = 24) lesions in non-cirrhotic liver were included. During the arterial phase (AP) of CEUS, ICC lesions exhibited heterogeneous hyperenhancement (13/30, 43.3%), heterogeneous hypo-enhancement (2/30, 6.7 %) and rim-like hyperenhancement (15/30, 50.0%), whereas all HCC lesions exhibited heterogeneous hyperenhancement (24/24, 100.0%) (p < 0.05). Subsequently, most of the ICC lesions exhibited AP wash-out (83.3%, 25/30), whereas a few cases exhibited wash-out in the portal venous phase (PVP) (15.7%, 5/30). In contrast, HCC lesions exhibited AP wash-out (41.7%, 10/24), PVP wash-out (41.7%, 10/24) and a small part of late phase wash-out (16.7%, 4/24) (p < 0.05). Compared with those of HCC lesions, TICs of ICCs revealed earlier and lower enhancement during the AP, faster decline during the PVP and reduced area under the curve. The combined area under the receiver operating characteristic curve (AUROC) of all significant parameters was 0.946, with 86.7% sensitivity, 95.8% specificity and 90.7% accuracy in differential diagnosis between ICC and HCC lesions in non-cirrhotic liver, which improved the diagnostic efficacy of CEUS (58.3% sensitivity, 90.0% specificity and 75.9% accuracy). CONCLUSION: ICC and HCC lesions in non-cirrhotic liver might exhibit some overlap of CEUS features in diagnosis. DCE-US with quantitative analysis would be helpful in pre-operative differential diagnosis.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/patologia , Estudos Retrospectivos , Diagnóstico Diferencial , Meios de Contraste , Colangiocarcinoma/complicações , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/patologia , Ultrassonografia , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/patologia
10.
Diagnostics (Basel) ; 13(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36766624

RESUMO

OBJECTIVE: This study seeks to evaluate the value of the high-frame-rate vector flow imaging technique in assessing the hemodynamic changes of carotid atherosclerotic stenosis in aging people (>60 years old). METHODS: Aging patients diagnosed with carotid atherosclerotic stenosis who underwent carotid high-frame-rate vector flow imaging examination were prospectively enrolled. A Mindray Resona7s ultrasound machine equipped with high-frame-rate vector flow function was used for ultrasound evaluation. First, B mode ultrasound and color Doppler flow imaging were used to evaluate carotid stenosis. Then, the vector arrows and flow streamline detected by V Flow were analyzed and the wall shear stress values (Pa) at the carotid stenosis site were measured. All patients were divided into symptomatic and asymptomatic groups according to whether they had acute/subacute stroke or other clinical symptoms within 2 weeks before ultrasound examination. The results of digital subtraction angiography or computed tomography angiography were used as the gold standard. The stenosis rate was calcified, according to North American Symptomatic Carotid Endarterectomy Trial criteria. The diagnostic values of wall shear stress, conventional ultrasound, and the combined diagnosis in carotid atherosclerotic stenosis were compared. RESULTS: Finally, 88 patients with carotid atherosclerotic plaque were enrolled (71 males (80.7%), mean age 67.6 ± 5.4 years). The success rate of high-frame-rate vector flow imaging was 96.7% (88/91). The WSS value of symptomatic carotid stenosis (1.4 ± 0.15 Pa) was significantly higher than that of asymptomatic carotid stenosis (0.80 ± 0.08 Pa) (p < 0.05). Taking the wall shear stress value > 0.78 Pa as the diagnostic criteria for symptomatic carotid atherosclerotic plaque, the area under receiver operating characteristic curves was 0.79 with 87.1% sensitivity and 69.6% specificity. The area under receiver operating characteristic curves of the combined diagnosis (0.966) for differentiating severe carotid atherosclerotic stenosis was significantly higher than that of conventional ultrasound and WSS value, with 89.7% sensitivity and 93.2% specificity (p < 0.05). CONCLUSION: As a non-invasive imaging method, the high-frame-rate vector flow imaging technique showed potential value in the preoperative assessment of the symptomatic carotid atherosclerotic stenosis and diagnosing carotid atherosclerotic stenosis in aging patients.

11.
Clin Hemorheol Microcirc ; 84(1): 43-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36683501

RESUMO

OBJECTIVE: To explore the value of vascular architecture detected by micro vascular imaging (MVI) in preoperative diagnosis of focal liver lesions (FLLs). METHODS: In this retrospective study, patients with surgery and histopathologically proved or radiologically confirmed FLLs were included. Vascular architecture of FLLs were acquired by color Doppler flow imaging (CDFI) and MVI on LOGIQ™ E20 ultrasound machine (C1-6 convex array probes). Alder semiquantitative analysis (grade 0-3) and morphologic features of blood vessels (pattern a-f) were used to assess the blood flow within the FLLs. Interobserver agreement for evaluating blood flow of FLLs was analyzed. Using Adler's grading or morphologic patterns as diagnostic criteria for malignant FLLs, the diagnostic efficiency was analyzed and compared. RESULTS: From October 2021 and February 2022, 50 patients diagnosed with 40 malignant FLLs and 10 benign FLLs were finally included. The Kappa value within two observers for evaluating the blood flow of FLLs was 0.78 for MVI and 0.55 for CDFI. According to Alder semiquantitative analysis, more high-level blood flow signals (grade 2-3) were detected by MVI than CDFI (P < 0.05). Based on high-level blood flow signals (grade 2-3) and hypervascular supply patterns (pattern e and f), the diagnostic accuracy for malignant FLLs were 76% and 68% for MVI, 56% and 38% for CDFI, respectively. CONCLUSION: MVI is superior to CDFI in evaluating vascular architecture of FLLs. The high-level flow signals and hypervascular pattern detected by MVI have a useful and complementary value in preoperative non-invasive identification of malignant FLLs.


Assuntos
Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Estudos Retrospectivos , Fígado/diagnóstico por imagem , Fígado/patologia , Ultrassonografia , Microvasos/diagnóstico por imagem , Sensibilidade e Especificidade , Diagnóstico Diferencial
12.
Diagnostics (Basel) ; 13(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36673048

RESUMO

Objective: To investigate whether the dynamic contrast-enhanced ultrasound (DCE-US) analysis and quantitative parameters could be helpful for predicting histopathologic grades of pancreatic neuroendocrine tumors (pNETs). Methods: This retrospective study conducted a comprehensive review of the CEUS database between March 2017 and November 2021 in Zhongshan Hospital, Fudan University. Ultrasound examinations were performed by an ACUSON Sequioa unit equipped with a 3.5 MHz 6C−1 convex array transducer, and an ACUSON OXANA2 unit equipped with a 3.5 MHz 5C−1 convex array transducer. SonoVue® (Bracco Inc., Milan, Italy) was used for all CEUS examinations. Time intensity curves (TICs) and quantitative parameters of DCE-US were created by Vuebox® software (Bracco, Italy). Inclusion criteria were: patients with histopathologically proved pNETs, patients who underwent pancreatic B-mode ultrasounds (BMUS) and CEUS scans one week before surgery or biopsy and had DCE-US imaging documented for more than 2 min, patients with solid or predominantly solid lesions and patients with definite diagnosis of histopathological grades of pNETs. Based on their prognosis, patients were categorized into two groups: pNETs G1/G2 group and pNETs G3/pNECs group. Results: A total of 42 patients who underwent surgery (n = 38) or biopsy (n = 4) and had histopathologically confirmed pNETs were included. According to the WHO 2019 criteria, all pNETs were classified into grade 1 (G1, n = 10), grade 2 (G2, n = 21), or grade 3 (G3)/pancreatic neuroendocrine carcinomas (pNECs) (n = 11), based on the Ki−67 proliferation index and the mitotic activity. The majority of the TICs (27/31) of pNETs G1/G2 were above or equal to those of pancreatic parenchyma in the arterial phase, but most (7/11) pNETs G3/pNECs had TICs below those of pancreatic parenchyma from arterial phase to late phase (p < 0.05). Among all the CEUS quantitative parameters of DCE-US, values of relative rise time (rPE), relative mean transit time (rmTT) and relative area under the curve (rAUC) were significantly higher in pNETs G1/G2 group than those in pNETs G3/pNECs group (p < 0.05). Taking an rPE below 1.09 as the optimal cut-off value, the sensitivity, specificity and accuracy for prediction of pNETs G3/pNECs from G1/G2 were 90.91% [58.70% to 99.80%], 67.64% [48.61% to 83.32%] and 85.78% [74.14% to 97.42%], respectively. Taking rAUC below 0.855 as the optimal cut-off value, the sensitivity, specificity and accuracy for prediction of pNETs G3/pNECs from G1/G2 were 90.91% [66.26% to 99.53%], 83.87% [67.37% to 92.91%] and 94.72% [88.30% to 100.00%], respectively. Conclusions: Dynamic contrast-enhanced ultrasound analysis might be helpful for predicting the pathological grades of pNETs. Among all quantitative parameters, rPE, rmTT and rAUC are potentially useful parameters for predicting G3/pNECs with aggressive behavior.

13.
Diagnostics (Basel) ; 12(11)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36359506

RESUMO

Objective: To evaluate the value of dynamic contrast-enhanced ultrasound (DCE-US) and quantitative parameters in early prediction of tumor response to chemoradiotherapy (CRT) in patients with locally advanced pancreatic ductal adenocarcinoma (LAPC). Patients and Methods: In this prospective study, patients with biopsy-proved and histopathologically proved LAPC who underwent regular CRT were recruited. DCE-US evaluations were performed before and four months after CRT. SonoVue-enhanced contrast-enhanced ultrasound (CEUS) was performed by an ultrasound system (ACUSON Sequoia; Siemens Medical Solutions, USA) equipped with a 5C1 MHz convex array transducer. Time−intensity curves were created by VueBox software (Bracco, Italy), and various DCE-US quantitative parameters were obtained. Taking Response Evaluation Criteria in Solid Tumors (RECIST) based on computed tomography (CT) or magnetic resonance imaging (MRI) as the gold standard, DCE-US parameters were compared between the treatment responder group (RG) and non-responder group (NRG). The correlation between the DCE-US parameters and the serum carbohydrate antigen 19-9 (CA 19-9) level was also analyzed. Results: Finally, 21 LAPC patients (mean age 59.3 ± 7.2 years) were included. In comparing the RG (n = 18) and NRG (n = 3), no significant change could be found among the mean size of the lesions (31.2 ± 8.1 mm vs. 27.2 ± 8.3 mm, p = 0.135). In comparing the TICs between the two groups, the LAPC lesions in the RG took a longer time to reach peak enhancement and to wash out. Among all the DCE-US parameters, RT (rise time), WiAUC (wash-in area under the curve), WoAUC (wash-out area under the curve) and WiWoAUC (wash-in and wash-out area under the curve) decreased significantly after CRT in the RG (p < 0.05). The RT ratio, WiAUC ratio, WoAUC ratio and WiWoAUC ratio were closely correlated with the change in serum CA 19-9 level in the RG (p < 0.05). Conclusion: DCE-US might be a potential imaging method for non-invasive follow-up for early response in LAPC patients treated by CRT.

14.
Diagnostics (Basel) ; 12(10)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36291962

RESUMO

PURPOSE: To investigate the Sonazoid-enhanced contrast-enhanced ultrasound (CEUS) features of hepatocellular carcinoma (HCC) in a non-cirrhosis liver background, in comparison to those in liver cirrhosis. METHODS: In this retrospective study, 19 patients with surgery and histopathologically proven HCC lesions in non-cirrhosis liver background were included regarding Sonazoid-enhanced CEUS characteristics. Two radiologists evaluated the CEUS features of HCC lesions according to the WFUMB (World Federation of Societies for Ultrasound in Medicine and Biology) guidelines criteria. Thirty-six patients with HCC lesions in liver cirrhosis were included as a control group. Final diagnoses were confirmed by surgery and histopathological results. RESULTS: Liver background of the non-cirrhosis group including normal liver (n = 7), liver fibrosis (n = 11), and alcoholic liver disease (n = 1). The mean size of non-cirrhosis HCC lesions was 60.8 ± 46.8 mm (ranging from 25 to 219 mm). During the arterial phase of Sonazoid-enhanced CEUS, most HCCs in non-cirrhotic liver (94.7%, 18/19) and in cirrhotic liver (83.3%, 30/36) presented non-rim hyperenhancement. During the portal venous phase, HCC lesions in the non-cirrhosis liver group showed relatively early washout (68.4%, 13/19) (p = 0.090). Meanwhile, HCC lesions in liver cirrhosis background showed isoenhancement (55.6%, 20/36). All lesions in the non-cirrhotic liver group showed hypoenhancement in the late phase and the Kupffer phase (100%, 19/19). Five cases of HCC lesions in liver cirrhosis showed isoenhancement during the late phase and hypoenhancement during the Kupffer phase (13.9%, 5/36). The rest of the cirrhotic HCC lesions showed hypoenhancement during the late phase and the Kupffer phase (86.1%, 31/36). Additional hypoenhanced lesions were detected in three patients in the non-cirrhosis liver group and eight patients in the liver cirrhosis group (mean size: 13.0 ± 5.6 mm), which were also suspected to be HCC lesions. CONCLUSIONS: Heterogeneous hyperenhancement during the arterial phase as well as relatively early washout are characteristic features of HCC in the non-cirrhotic liver on Sonazoid-enhanced CEUS.

15.
Diagnostics (Basel) ; 12(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36140576

RESUMO

Objectives: Histopathological tumor grade and Ki-67 expression level are key aspects concerning the prognosis of patients with hepatocellular carcinoma (HCC) lesions. The aim of this study was to investigate whether the radiomics model derived from Sonazoid contrast-enhanced (S-CEUS) images could predict histological grades and Ki-67 expression of HCC lesions. Methods: This prospective study included 101 (training cohort: n = 71; validation cohort: n = 30) patients with surgical resection and histopathologically confirmed HCC lesions. Radiomics features were extracted from the B mode and Kupffer phase of S-CEUS images. Maximum relevance minimum redundancy (MRMR) and least absolute shrinkage and selection operator (LASSO) were used for feature selection, and a stepwise multivariate logit regression model was trained for prediction. Model accuracy, sensitivity, and specificity in both training and testing datasets were used to evaluate performance. Results: The prediction model derived from Kupffer phase images (CE-model) displayed a significantly better performance in the prediction of stage III HCC patients, with an area under the receiver operating characteristic curve (AUROC) of 0.908 in the training dataset and 0.792 in the testing set. The CE-model demonstrated generalizability in identifying HCC patients with elevated Ki-67 expression (>10%) with a training AUROC of 0.873 and testing AUROC of 0.768, with noticeably higher specificity of 92.3% and 80.0% in training and testing datasets, respectively. Conclusions: The radiomics model constructed from the Kupffer phase of S-CEUS images has the potential for predicting Ki-67 expression and histological stages in patients with HCC.

16.
Clin Hemorheol Microcirc ; 81(2): 149-161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35253737

RESUMO

OBJECTIVE: To explore the value of dynamic contrast enhanced ultrasound (DCE-US) in preoperative differential diagnosis of focal-type autoimmune pancreatitis (AIP) and pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: From May 2016 to March 2020, patients with biopsy and histopathologically confirmed focal-type AIP (n = 9) were retrospectively included. All patients received contrast enhanced ultrasound (CEUS) examinations one week before surgery/biopsy. Dynamic analysis was performed by VueBox® software (Bracco, Italy). Eighteen cases of resection and histopathologically proved PDAC lesions were also included as control group. B mode ultrasound (BMUS) features, CEUS enhancement patterns, time intensity curves (TICs) and CEUS quantitative parameters were obtained and compared between AIP and PDAC lesions. RESULTS: After injection of ultrasound contrast agents, most focal-type AIP lesions displayed hyper-enhancement (2/9, 22.2%) or iso-enhancement (6/9, 66.7%) during arterial phase of CEUS, while most of PDAC lesions showed hypo-enhancement (88.9%) (P < 0.01). During late phase, most of AIP lesions showed iso-enhancement (8/9, 88.9%), while most of PDAC lesions showed hypo-enhancement (94.4%) (P < 0.001). Compared with PDAC lesions, TICs of AIP lesions showed delayed and higher enhancement. Among all CEUS perfusion parameters, ratio of PE (peak enhancement), WiAUC (wash-in area under the curve), WiR (wash-in rate), WiPI (wash-in perfusion index, WiPI = WiAUC/ rise time), WoAUC (wash-out area under the curve), WiWoAUC (wash-in and wash-out area under the curve) and WoR (wash-out rate) between pancreatic lesion and surrounding normal pancreatic tissue were significantly higher in AIP lesions than PDAC lesions (P < 0.05). CONCLUSION: DCE-US with quantitative analysis has the potential to make preoperative differential diagnosis between focal-type AIP and PDAC non-invasively.


Assuntos
Adenocarcinoma , Pancreatite Autoimune , Neoplasias Pancreáticas , Meios de Contraste , Diagnóstico Diferencial , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias Pancreáticas
17.
Mitochondrial DNA B Resour ; 7(1): 98-100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34993325

RESUMO

Libanotis buchtormensis (Fisch.) DC. is one of the traditional Chinese herbal medicines in the Qinling District, while the genetic information is limited. In the study, we reported the complete chloroplast genome of L. buchtormensis using BGISEQ-500 sequencing data. The complete chloroplast genome was 147,036 bp in length with a GC content of 37.6%, consisting of four parts, namely LSC (91,969 bp), SSC (17,469 bp), and two IRs (18,799 bp in each). The cp genome contained 127 genes, including 83 CDS genes, 36 tRNA genes, and 8 rRNA genes. The phylogenetic analysis showed that L. buchtormensis was sister to Ledebouriella seseloides.

18.
Clin Hemorheol Microcirc ; 81(1): 97-107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35001883

RESUMO

OBJECTIVES: To establish and to evaluate a machine learning radiomics model based on grayscale and Sonazoid contrast enhanced ultrasound images for the preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) patients. METHODS: 100 cases of histopathological confirmed HCC lesions were prospectively included. Regions of interest were segmented on both grayscale and Kupffer phase of Sonazoid contrast enhanced (CEUS) images. Radiomic features were extracted from tumor region and region containing 5 mm of peritumoral liver tissues. Maximum relevance minimum redundancy (MRMR) and Least Absolute Shrinkage and Selection Operator (LASSO) were used for feature selection and Support Vector Machine (SVM) classifier was trained for radiomic signature calculation. Radiomic signatures were incorporated with clinical variables using univariate-multivariate logistic regression for the final prediction of MVI. Receiver operating characteristic curves, calibration curves and decision curve analysis were used to evaluate model's predictive performance of MVI. RESULTS: Age were the only clinical variable significantly associated with MVI. Radiomic signature derived from Kupffer phase images of peritumoral liver tissues (kupfferPT) displayed a significantly better performance with an area under the receiver operating characteristic curve (AUROC) of 0.800 (95% confidence interval: 0.667, 0.834), the final prediction model using age and kupfferPT achieved an AUROC of 0.804 (95% CI: 0.723, 0.878), accuracy of 75.0%, sensitivity of 87.5% and specificity of 69.1%. CONCLUSIONS: Radiomic model based on Kupffer phase ultrasound images of tissue adjacent to HCC lesions showed an observable better predictive value compared to grayscale images and has potential value to facilitate preoperative identification of HCC patients at higher risk of MVI.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Compostos Férricos , Humanos , Ferro , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Invasividade Neoplásica , Óxidos , Estudos Prospectivos , Estudos Retrospectivos
19.
Pancreatology ; 21(8): 1498-1505, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34580017

RESUMO

OBJECTIVES: The aim of this study was to quantitatively evaluate the stiffness of pancreatic parenchyma and solid focal pancreatic lesions (FPLs) by virtual touch tissue imaging and quantification (VTIQ) technique and to investigate the potential usefulness of VTIQ method in the prediction of post-operative pancreatic fistula (POPF) after pancreatectomy. METHODS: In this prospective study, patients who scheduled to undergo pancreatectomy were initially enrolled and received VTIQ assessment within one week before surgery. VTIQ elastography (Siemens ACUSON Sequoia, 5C-1 transducer) was used to measure the shear wave velocity (SWV) value of FPLs and the body part pancreatic parenchyma. The palpation stiffness of pancreas was qualitatively evaluated during operation by surgeons. POPF was finally diagnosed and graded through a three-weeks post-operative follow-up according to international study group of pancreatic fistula (ISGPF). SWV values were compared between POPF positive and negative group. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic efficacy of SWV value in predicting POPF. RESULTS: From December 2020 to June 2021, 44 patients were finally enrolled in this study, among which, 26 patients were identified to develop POPF after pancreatectomy. The SWV value of pancreatic parenchyma in POPF positive group was significantly lower than that in POPF negative group (P = 0.001). However, there was no significant difference in palpation stiffness between the two groups (P = 0.124). Besides, neither the SWV value of FPL nor the SWV ratio between FPL to surrounding pancreatic parenchyma differ significantly between POPF positive and negative group (P > 0.05). Taking SWV value of pancreatic parenchyma >1.10 m/s as a cut-off value for predicting POPF, area under the receiver operating characteristic curve (AUROC) was 0.864 with 72.2% sensitivity, 92.3% specificity, 86.7% positive predictive value (PPV) and 82.8% negative predictive value (NPV), respectively. CONCLUSIONS: VTIQ technique might be a potential non-invasive imaging method to predict POPF before pancreatectomy in future clinical practice.


Assuntos
Técnicas de Imagem por Elasticidade , Fístula Pancreática , Humanos , Pancreatectomia , Fístula Pancreática/diagnóstico por imagem , Fístula Pancreática/etiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Prospectivos , Sensibilidade e Especificidade , Tecnologia
20.
Clin Hemorheol Microcirc ; 77(3): 323-333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33252067

RESUMO

PURPOSE: To evaluate the feasibility of dynamic contrast enhanced ultrasound (DCE-US) in predicting treatment response of high-intensity focused ultrasound (HIFU) in patients with locally advanced pancreatic cancer (LAPC) lesions. PATIENTS AND METHODS: In this prospective study, 10 patients with pathologically confirmed LAPC lesions (7 men, 3 women; average age, 61.13±5.80 years) were prospectively enrolled. All patients received HIFU treatment with peak intensity at 12000 W/cm2. Contrast enhanced ultrasound (CEUS) was performed with an ACUSON Oxana 2 ultrasound equipment and a 6 C-1 transducer (1-6 Hz). A dose of 2.4 ml SonoVue was injected for each examination. Time intensity curves (TICs) were generated and quantitative analyses were performed by SonoLiver software. B mode ultrasound (BMUS) features, CEUS enhancement patterns, TICs, CEUS quantitative parameters and serum carcinoma antigen 19-9 (CA19-9) levels were compared before and 4 weeks after HIFU treatment. Statistical analyses were performed with SPSS Version 20.0 and GraphPad Prism 5. RESULTS: While comparing before and after HIFU, no significant difference was obtained on mean size of lesion, BMUS or CEUS features. After HIFU treatment, TICs showed decreased and delayed enhancement. Among all CEUS quantitative parameters, significant decrease could be found in maximum intensity (MI) (60.66±23.95% vs 41.31±26.74%) and mean transit time (mTT) (76.66±47.61 s vs 38.42±28.35 s). CA19-9 level decreased significantly after HIFU (2747.92±4237.41 U/ml vs 715.08±1773.90 U/ml) (P = 0.05). CONCLUSION: DCE-US combining with quantitative analysis might be a useful imaging method for early treatment response evaluation of HIFU in LAPC lesions.


Assuntos
Meios de Contraste/uso terapêutico , Tratamento por Ondas de Choque Extracorpóreas/métodos , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
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