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2.
Nat Commun ; 15(1): 4258, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769155

RESUMO

Thermal fatigue is a common failure mode in electronic solder joints, yet the role of microstructure is incompletely understood. Here, we quantify the evolution of microstructure and damage in Sn-3Ag-0.5Cu joints throughout a ball grid array (BGA) package using EBSD mapping of localised subgrains, recrystallisation and heavily coarsened Ag3Sn. We then interpret the results with a multi-scale modelling approach that links from a continuum model at the package/board scale through to a crystal plasticity finite element model at the microstructure scale. We measure and explain the dependence of damage evolution on (i) the ß-Sn crystal orientation(s) in single and multigrain joints, and (ii) the coefficient of thermal expansion (CTE) mismatch between tin grains in cyclic twinned multigrain joints. We further explore the relative importance of the solder microstructure versus the joint location in the array. The results provide a basis for designing optimum solder joint microstructures for thermal fatigue resistance.

4.
Zhonghua Gan Zang Bing Za Zhi ; 31(8): 862-868, 2023 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-37723069

RESUMO

Objective: Plateletcrit (PCT) is considered a new potential index to predict the degree of liver fibrosis in patients with chronic hepatitis B (CHB). This study aimed to explore the predictive value of PCT for the degree of liver fibrosis in patients with chronic hepatitis B virus (HBV) infection with alanine aminotransferase (ALT) < 2× upper limit of normal (ULN). Measurement data were compared using the t-test, ANOVA, or non-parametric test (Mann-Whitney U test). Categorical variables were compared using χ (2) test or Fisher's exact test. Methods: 140 cases with chronic HBV infection who underwent liver biopsy and ALT < 2×ULN were enrolled from January 2016 to March 2021. Univariate and multivariate logistic regression and the area under the receiver operating characteristic curve (AUC) were used to determine the predictive value of PCT for the degree of liver fibrosis. The likelihood ratio (LR) was used to optimize the selection of the diagnostic cut-off. Results: (1) Among the 140 cases, there were 34 (24.3%) cases in the S0 stage, 47 (33.6%) cases in the S1 stage, 16 (11.4%) cases in the S2 stage, 19 (13.6%) cases in the S3 stage, and 24 (17.1%) cases in the S4 stage. The overall mean PCT level was 0.19 ± 0.06%. (2) Univariate analysis revealed that PCT between patients with stages of liver fibrosis was S(0-1) and S(2-4) (0.20% ± 0.05% vs. 0.16% ± 0.06%, t = 3.955, P < 0.001), S(0 -2) and S(3-4) (0.20% ± 0.05% vs. 0.15% ± 0.06%, t = 5.631, P < 0.001) and S(0-3) and S4 (0.20% ± 0.05% vs. 0.12% ± 0.05%, t = 7.113, P < 0.001), respectively, and the differences were statistically significant. Multivariate logistic regression analysis showed that PCT was an independent risk factor for liver fibrosis stages S(2-4), S(3-4), and S4 (OR = 0.925, 95% CI: 0.859 - 0.997, P = 0.042; OR = 0.867, 95% CI: 0.789 - 0.954, P = 0.003; OR = 0.708, 95% CI: 0.593 - 0.846; P < 0.001). (3) The AUCs of PCT were 0.702, 0.777, and 0.885 for diagnosing liver fibrosis stages S(2-4), S(3-4), and S4 in patients with chronic HBV infection with ALT < 2×ULN. PCT was superior for the cirrhosis (S4) diagnosis. 92 (65.7%) cases were diagnosed as cirrhosis or non-cirrhosis according to the LR optimized diagnostic and exclusion diagnostic cut-offs (≤0.09%, ≤0.17%), with an accuracy of 97.8%. Conclusion: PCT has a high diagnostic and exclusion value for cirrhotic patients with chronic HBV infection with ALT < 2×ULN. Furthermore, it can be used as a non-invasive diagnostic index for determining and assisting the diagnosis of cirrhosis in resource-constrained areas, reducing the need for pathological examination of liver biopsies, and it has the advantage of being simple and intuitive without complex calculations.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Hepatite B Crônica/complicações , Cirrose Hepática/diagnóstico , Fatores de Risco , Alanina Transaminase
5.
Zhonghua Yi Xue Za Zhi ; 103(31): 2427-2432, 2023 Aug 22.
Artigo em Chinês | MEDLINE | ID: mdl-37599217

RESUMO

Objective: To investigate the diagnostic performance of multiparametric dynamic contrast-enhanced MRI(DCE-MRI) for the differentiation between benign and malignant larcrimal gland epithelial tumors. Methods: The clinical and imaging data of 104 patients with epithelial tumors of the lacrimal gland who underwent orbital MRI scan and met the inclusion criteria in Beijing Tongren Hospital from January 2011 to December 2017 were retrospectively collected, including 48 males and 56 females, aged from 12 to 77 (43±7) years. Sixty-three cases of benign epithelial tumors and 41 cases of malignant epithelial tumors were examined by DCE-MRI. The parameters of semiquantitative analysis including: time to peak enhancement (Tpeak), maximum enhancement ratio (ERmax), Slope, washout ratio (WR) and time-signal intensity curve (TIC) types. The parameters of quantitative analysis including: volume transfer constant (Ktrans), the extravascular extracellular volume fraction (Ve) and rate constant (Kep). Receiver operating characteristic (ROC) curve analysis was performed for DCE-MRI parameters with statistically significant differences, the area under the curve (AUC) was calculated, the diagnostic threshold was determined, and the diagnostic performance was evaluated. Logistic regression analysis was used to determine the best parameters for differential diagnosis of benign and malignant epithelial tumors of the lacrimal gland. Results: For the semiquantitative analysis of DCE-MRI, malignant lacrimal gland epithelial tumor had a significantly shorter Tpeak than benign masses [(103.77±57.87) s vs (187.80±77.01) s,P<0.001)], while had a higher value in ERmax, Slope [M(Q1,Q3)] and WR in malignant masses compared with benign one [1.55±0.39 vs 1.36±0.33; 1.76 (0.97,2.27) vs 0.62 (0.50,0.93); 7.70%(1.40%, 21.60%)% vs 0(0, 0),all P<0.05)].The TICs of benign lacrimal tumors mainly showed a persistent type (49/63),while most malignant lacrimal tumors mainly showed a plateau type (25/41). For the quantitative analysis of DCE-MRI, the values of Ktrans and Kep[M(Q1,Q3)] in malignant tumors were significantly greater than those of benign tumors (0.99±0.52/min vs 0.43±0.23/min, P<0.001; 1.33(0.83, 1.55)/min vs 0.55(0.46, 0.68)/min, P<0.001). No significant difference in Ve was found between the groups (0.76±0.20 vs 0.73±0.22,P=0.467). Through the statistical analysis, TIC types (OR=3.887,95%CI: 1.409-10.725) and Ktrans(OR=50.979,95%CI: 6.046-429.830) can provide superior diagnostic performance for predicting malignant lacrimal gland epithelial tumors, with a sensitivity of 78.05%, specificity of 77.78%,and sensitivity of 70.73%, specificity of 95.24%, respevtively. Furthermore, the comprehensive diagnostic performance of Ktrans in AUC was proven to be significantly better than that of TIC [0.875 (0.796-0.932) vs 0.798 (0.708-0.870),P=0.049]. Conclusions: Multiparametric DCE-MRI is helpful for the differential diagnosis of benign and malignant epithelial tumors of lacrimal gland. TIC type and Ktrans have higher diagnostic value, and the diagnostic performance of Ktrans is better than that of TIC.


Assuntos
Carcinoma , Neoplasias Oculares , Aparelho Lacrimal , Neoplasias Epiteliais e Glandulares , Feminino , Masculino , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Neoplasias Oculares/diagnóstico por imagem
6.
Clin Radiol ; 78(11): e864-e871, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37596180

RESUMO

AIM: To investigate the value of orbital magnetic resonance imaging (MRI) features in predicting the efficacy of intravenous chemotherapy (IVC) for patients with retinoblastoma (RB). MATERIALS AND METHODS: The pretreatment clinical and MRI data of 100 eyes from 80 RB patients who underwent IVC were collected retrospectively. There were 59 eyes in the effective group and 41 eyes in the ineffective group, and the baseline data of the two groups were compared statistically. Three radiologists reviewed and evaluated each lesion independently based on 25 MRI features. The predictive values of the MRI features for IVC efficacy were assessed by multi-factor logistic regression analysis, and their odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Receiver operating characteristic curves (ROCs) with the area under the curve (AUC) were used to determine the predictive abilities. A predictive model was constructed by integrating all independent predictors visualised by the nomogram. RESULTS: There were no statistically significant differences in sex or age between the effective and ineffective groups. The results of multivariate regression analysis showed that laterality, margin, and anterior eye segment enhancement were identified as independent factors that could predict IVC efficacy. The predictive model combining these three features was constructed, and it had an AUC of 0.732 (95% CI: 0.633, 0.831, p<0.01), a sensitivity of 71.2%, and a specificity of 70.7%. CONCLUSION: The data demonstrate that the orbital MRI features can be used to predict IVC efficiency before RB patients are treated.

9.
Neurol India ; 70(1): 68-73, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35263856

RESUMO

Background: Tumors of the axis (C2) are rare, which represents unique surgical challenges. Aim: To describe clinical outcomes and efficacy of transoral curettage and posterior instrumentation for treating C2 tumors, with a minimum 2-year follow-up. Setting and Design: This was a retrospective study conducted at a grade 3A hospital in China. Materials and Methods: From August 2015 to May 2017, patients diagnosed with benign C2 tumors were collected in the retrospective study. The Weinstein-Boriani-Biagini anatomic zone classification was used to characterize the tumors. The Japanese Orthopedic Association (JOA) score and the visual analog scale (VAS) pain scores were recorded pre and postoperatively. All patients were treated with posterior instrumentation and transoral curettage for tumor excision and iliac crest graft for arthrodesis. Results: Five patients were included in this report. The tumors involving C2 were all benign tumors. The JOA and VAS scores improved significantly at a 3-month follow-up, and the clinical symptoms were stable at the 12-month follow-up. Computed tomography (CT) scans at a 6-month follow-up showed solid arthrodesis in all patients. With a minimum 2-year follow-up, there was no implant loosening or tumor recurrence. Conclusion: The transoral curettage coupled with posterior instrumentation with iliac crest graft provides a reasonable option for the treatment of benign C2 tumors.


Assuntos
Neoplasias , Fusão Vertebral , Curetagem , Fixação Interna de Fraturas , Humanos , Ílio , Estudos Retrospectivos , Fusão Vertebral/métodos , Resultado do Tratamento
10.
Zhonghua Yan Ke Za Zhi ; 58(1): 41-45, 2022 Jan 11.
Artigo em Chinês | MEDLINE | ID: mdl-34979792

RESUMO

Objective: To investigate the cognitive effects of monocular blindness and related influencing factors. Methods: A cross-sectional study was conducted. The patients with monocular blindness (the age of onset <16 years) were enrolled from Beijing Tongren Eye Center, Beijing Tongren Hospital between January 2018 and June 2020. The Montreal cognitive assessment (MoCA) scale was applied to assess seven cognitive domains including visuospatial and executive function, naming, attention, etc. Based on MoCA scores, all the patients were classified into two groups: normal cognitive functions and cognitive impairment. Spearman's correlation was used to perform the single factor analysis of the influencing factors of cognitive functions. Multivariate linear regression analyses were applied to identify the independent influencing risk factors. Results: A total of 45 patients with monocular blindness were enrolled. There were 25 males and 20 females, with age at testing being (27±10) years.The incidence of cognitive impairment in 45 patients was 60.0% (27/45). The abnormal items ranking from a high to low rate were language (95.6%, 43 cases), delayed recall (75.6%, 34 cases), visuospatial and executive function (60.0%, 27 cases), abstract (44.4%, 20 cases), attention (35.6%, 16 cases), naming (20.0%, 9 cases), and orientation (0%). There were statistically significant differences (all P<0.05) in total score (21.9±3.3 vs. 27.4±1.4), visuospatial and executive function (3.2±1.7 vs. 4.6±0.7), naming (2.7±0.6 vs. 2.9±0.2), attention (5.3±1.0 vs. 5.8±0.4), language (1.1±0.8 vs. 1.8±0.8), abstract (1.1±0.8 vs. 1.8±0.5) and delayed recall (2.3±1.3 vs. 4.4±0.8) between two groups of patients with and without cognitive impairment. Spearman's correlation analysis showed visuospatial and executive functions, attention, abstract and MoCA total score were positively correlated with education years (correlation coefficients being 0.355, 0.424, 0.434 and 0.370, respectively; all P<0.05). Multiple linear regression showed that duration of blindness was correlated with naming (ß=-0.325), and years of education correlated with attention (ß=0.472), abstract ability (ß=0.441) and MoCA total score (ß=0.390) (all P<0.05). Conclusions: Monocular blindness may affect language, delayed memory and visuospatial executive functions. The duration of blindness is an independent risk factor, and higher education is a protective factor of the cognitive impairment.


Assuntos
Disfunção Cognitiva , Adolescente , Cegueira , Cognição , Estudos Transversais , Função Executiva , Feminino , Humanos , Masculino
11.
Ultrasound Obstet Gynecol ; 59(3): 304-316, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34940999

RESUMO

OBJECTIVES: To develop and validate an artificial intelligence system, the Prenatal ultrasound diagnosis Artificial Intelligence Conduct System (PAICS), to detect different patterns of fetal intracranial abnormality in standard sonographic reference planes for screening for congenital central nervous system (CNS) malformations. METHODS: Neurosonographic images from normal fetuses and fetuses with CNS malformations at 18-40 gestational weeks were retrieved from the databases of two tertiary hospitals in China and assigned randomly (ratio, 8:1:1) to training, fine-tuning and internal validation datasets to develop and evaluate the PAICS. The system was built based on a real-time convolutional neural network (CNN) algorithm, You Only Look Once, version 3 (YOLOv3). An image dataset from a third tertiary hospital was used to further validate, externally, the performance of the PAICS and to compare its performance with that of sonologists with different levels of expertise. Furthermore, a prospective video dataset was employed to evaluate the performance of the PAICS in a real-time scan scenario. The diagnostic accuracy, sensitivity, specificity and area under the receiver-operating-characteristics curve (AUC) were calculated to assess the performance of the PAICS and to compare this with the performance of sonologists with different levels of experience. RESULTS: In total, 43 890 images from 16 297 pregnancies and 169 videos from 166 pregnancies were used to develop and validate the PAICS. The system achieved excellent performance in identifying 10 types of intracranial image pattern, with macro- and microaverage AUCs, respectively, of 0.933 (95% CI, 0.798-1.000) and 0.977 (95% CI, 0.970-0.985) for the internal validation image dataset, 0.902 (95% CI, 0.816-0.989) and 0.898 (95% CI, 0.885-0.911) for the external validation image dataset and 0.969 (95% CI, 0.886-1.000) and 0.981 (95% CI, 0.974-0.988) in the real-time scan setting. The performance of the PAICS was comparable to that of expert sonologists in terms of macro- and microaverage accuracy (P = 0.863 and P = 0.775, respectively), sensitivity (P = 0.883, P = 0.846) and AUC (P = 0.891, P = 0.788), but required significantly less time (0.025 s per image for PAICS vs 4.4 s for experts, P < 0.001). CONCLUSIONS: Both in the image dataset and in the real-time scan setting, the PAICS achieved excellent diagnostic performance for various fetal CNS abnormalities. Its performance was comparable to that of experts, but it required less time. A CNN algorithm can be trained to detect fetal CNS abnormalities. The PAICS has the potential to be an effective and efficient tool in screening for fetal CNS malformations in clinical practice. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Inteligência Artificial , Malformações do Sistema Nervoso , Área Sob a Curva , Feminino , Feto/anormalidades , Humanos , Malformações do Sistema Nervoso/diagnóstico por imagem , Gravidez , Estudos Prospectivos
14.
Nat Commun ; 11(1): 4979, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020468

RESUMO

Cellular senescence is a known driver of carcinogenesis and age-related diseases, yet senescence is required for various physiological processes. However, the mechanisms and factors that control the negative effects of senescence while retaining its benefits are still elusive. Here, we show that the rasGAP SH3-binding protein 1 (G3BP1) is required for the activation of the senescent-associated secretory phenotype (SASP). During senescence, G3BP1 achieves this effect by promoting the association of the cyclic GMP-AMP synthase (cGAS) with cytosolic chromatin fragments. In turn, G3BP1, through cGAS, activates the NF-κB and STAT3 pathways, promoting SASP expression and secretion. G3BP1 depletion or pharmacological inhibition impairs the cGAS-pathway preventing the expression of SASP factors without affecting cell commitment to senescence. These SASPless senescent cells impair senescence-mediated growth of cancer cells in vitro and tumor growth in vivo. Our data reveal that G3BP1 is required for SASP expression and that SASP secretion is a primary mediator of senescence-associated tumor growth.


Assuntos
Senescência Celular/fisiologia , DNA Helicases/metabolismo , Neoplasias/patologia , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Células A549 , Animais , Carcinogênese , Linhagem Celular , Movimento Celular , Citocinas/metabolismo , DNA Helicases/antagonistas & inibidores , DNA Helicases/deficiência , Humanos , Inflamação , Camundongos , Neoplasias/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/deficiência , RNA Helicases/antagonistas & inibidores , RNA Helicases/deficiência , Proteínas com Motivo de Reconhecimento de RNA/antagonistas & inibidores , Proteínas com Motivo de Reconhecimento de RNA/deficiência , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
15.
Zhonghua Yan Ke Za Zhi ; 56(9): 676-680, 2020 Sep 11.
Artigo em Chinês | MEDLINE | ID: mdl-32907300

RESUMO

Objective: To explore the role of the scoring and strain ratio methods of ultrasonic elastography in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Methods: A cross-sectional study. Twenty-five patients (25 eyes) with choroidal melanoma treated in the Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University from July to October 2016 were included in this study. There were 13 males and 12 females, with an average age of (48±12) years old. Twenty-five patients (25 eyes) with choroidal hemangioma treated in the same period were selected for differential diagnosis, including 12 males and 13 females, with an average age of (37±13) years. The lesions were examined by ultrasound elastography and scored, and the strain ratio of the tumor to the orbital tissue was measured. Two independent sample t test was used to compare the difference in the elasticity score and strain ratio between choroidal melanoma and choroidal hemangioma. The sensitivity, specificity and area under the receiver operating characteristic (ROC) curve were calculated to analyze the value of the two methods in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Results: The elastography score of choroidal melanoma was (3.48±0.77) points, including 2 points in 3 cases, 3 points in 8 cases, 4 points in 13 cases, and 5 points in 1 case. The elastography score of hemangioma was (2.28±0.46) points, including 2 points in 18 cases and 3 points in 7 cases. The difference in the elasticity score between patients with the two kinds of tumors was statistically significant (t=6.694, P<0.01). The strain ratio was 42.97±15.83 and 12.21±9.24 in the patients with choroidal melanoma and choroidal hemangioma, respectively, and the difference was statistically significant (t=8.392, P<0.01). Using 3 points as the diagnostic critical point of the elastography score, the sensitivity was 88.0%, the specificity was 72.0%, and the area under the ROC curve was 0.80 (95% cofidence interval: 0.663 to 0.900, P<0.01). Using 21.67 as the diagnostic critical point of the strain ratio, the sensitivity was 92.0%, the specificity was 92.0%, and the area under the ROC curve was 0.92 (95% cofidence interval: 0.808 to 0.978, P<0.01). Conclusions: Ultrasound elastography plays a role in the differential diagnosis of choroidal melanoma and choroidal hemangioma. The differential diagnostic value of the strain ratio method is higher than the scoring method. (Chin J Ophthalmol, 2020, 56: 676-680).


Assuntos
Técnicas de Imagem por Elasticidade , Hemangioma , Melanoma/diagnóstico por imagem , Adulto , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Ultrassom , Adulto Jovem
16.
J Dent Educ ; 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32905621

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic presented formidable challenges in our ability to impart in-person extra-mural clinical training, including the Geriatric and Special Needs Program, to a group of 20 fourth-year dental students. A new course delivery format was developed wherein students used a validated Rapid Oral Health Deterioration (ROHD) risk assessment tool to critically appraise clinical case information relating to a young adult with special needs. In the alternative virtual educational approach that was created, students applied an interprofessional practice concept leading to patient treatment planning outcomes. Providing adequate information, additional reading resources, a response template, clear instructions and a process-oriented assessment policy all ensured a good level of participation from students in the alternative learning format. An association was noted between students' staging of risk for ROHD and their subsequent recommendations for treatment.

17.
J Laryngol Otol ; 134(4): 354-361, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32284084

RESUMO

OBJECTIVE: To evaluate the upper airway morphology changes associated with ageing in adult Chinese patients with obstructive sleep apnoea. METHODS: A total of 124 male patients diagnosed with obstructive sleep apnoea by overnight polysomnography, who underwent upper airway computed tomography, were enrolled. The linear dimensions, cross-sectional area and volume of the upper airway region and the surrounding bony frame were measured. The association between ageing and upper airway morphology was analysed. RESULTS: Soft palate length, minimum cross-sectional area of the retroglossal region, lateral dimensions at the minimum cross-sectional area of the retropalatal and retroglossal regions, nasopharyngeal volume, and average cross-sectional area of the nasopharyngeal region were found to significantly increase with ageing in all patients, while the upper airway shape flattened with ageing. The volume of the retropalatal region increased with ageing among the patients with a body mass index of less than 24 kg/m2. The volume of parapharyngeal fat pad increased with ageing among patients with a body mass index greater than 28 kg/m2. CONCLUSION: A number of dimensional, cross-sectional and volumetric parameters of the pharynx increased with age, indicating that non-anatomical factors may play a more important role in the pathogenesis of obstructive sleep apnoea in aged patients.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Nasofaringe/patologia , Palato Mole/patologia , Faringe/patologia , Apneia Obstrutiva do Sono/fisiopatologia , Adolescente , Adulto , Fatores Etários , Índice de Massa Corporal , China/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/anatomia & histologia , Nasofaringe/diagnóstico por imagem , Palato Mole/anatomia & histologia , Palato Mole/diagnóstico por imagem , Faringe/anatomia & histologia , Faringe/diagnóstico por imagem , Polissonografia/métodos , Estudos Retrospectivos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
18.
Ultrasound Obstet Gynecol ; 56(4): 579-587, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31909548

RESUMO

OBJECTIVES: To evaluate the feasibility of using deep-learning algorithms to classify as normal or abnormal sonographic images of the fetal brain obtained in standard axial planes. METHODS: We included in the study images retrieved from a large hospital database from 10 251 normal and 2529 abnormal pregnancies. Abnormal cases were confirmed by neonatal ultrasound, follow-up examination or autopsy. After a series of pretraining data processing steps, 15 372 normal and 14 047 abnormal fetal brain images in standard axial planes were obtained. These were divided into training and test datasets (at case level rather than image level), at a ratio of approximately 8:2. The training data were used to train the algorithms for three purposes: performance of image segmentation along the fetal skull, classification of the image as normal or abnormal and localization of the lesion. The accuracy was then tested on the test datasets, with performance of segmentation being assessed using precision, recall and Dice's coefficient (DICE), calculated to measure the extent of overlap between human-labeled and machine-segmented regions. We assessed classification accuracy by calculating the sensitivity and specificity for abnormal images. Additionally, for 2491 abnormal images, we determined how well each lesion had been localized by overlaying heat maps created by an algorithm on the segmented ultrasound images; an expert judged these in terms of how satisfactory was the lesion localization by the algorithm, classifying this as having been done precisely, closely or irrelevantly. RESULTS: Segmentation precision, recall and DICE were 97.9%, 90.9% and 94.1%, respectively. For classification, the overall accuracy was 96.3%. The sensitivity and specificity for identification of abnormal images were 96.9% and 95.9%, respectively, and the area under the receiver-operating-characteristics curve was 0.989 (95% CI, 0.986-0.991). The algorithms located lesions precisely in 61.6% (1535/2491) of the abnormal images, closely in 24.6% (614/2491) and irrelevantly in 13.7% (342/2491). CONCLUSIONS: Deep-learning algorithms can be trained for segmentation and classification of normal and abnormal fetal brain ultrasound images in standard axial planes and can provide heat maps for lesion localization. This study lays the foundation for further research on the differential diagnosis of fetal intracranial abnormalities. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Feto/diagnóstico por imagem , Malformações do Sistema Nervoso/diagnóstico por imagem , Ultrassonografia Pré-Natal/classificação , Encéfalo/anormalidades , Encéfalo/embriologia , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Feto/anormalidades , Feto/embriologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Malformações do Sistema Nervoso/embriologia , Gravidez , Curva ROC , Sensibilidade e Especificidade
19.
Rhinology ; 58(1): 59-65, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31448805

RESUMO

BACKGROUND: Our previous study showed that convoluted cerebriform pattern (CCP)-based reverse tracing method in preoperative magnetic resonance imaging (MRI) is a reliable tool in predicting originating site of sinonasal inverted papilloma (SNIP). This study aimed to determine the underlying pathological mechanism of the preoperative MRI-CCP reverse tracing method by assessing the histopathological changes from the origin to the peripheral sites of SNIP. METHODOLOGY: The originating site of SNIP was predicted by preoperative MRI in 30 consecutive patients suspected to have primary SNIP. Samples of SNIP originating and peripheral sites were processed by pathological staining for evaluation of stroma score, micro-vessel density (MVD), and tight junction proteins (claudin-5, zonula occludens (ZO)-1 and occludin) expression. RESULTS: The originating site of SNIP was accurately predicted by preoperative MRI in all patients. Stroma scores, and MVD were significantly greater in the periphery of SNIP than in the originating site. In contrast, Claudin-5 expression in micro-vessels was greater at the originating site than the periphery. CONCLUSIONS: More edematous stroma and intensive micro-vessels with defective tight junction in periphery of SNIP result in more contrast agent diffusing and CCP that can only be observed at the periphery of SNIP on T2 and contrast-enhanced T1 weighted MR images, which may be the mechanisms underlying the CCP reverse tracing method.


Assuntos
Papiloma Invertido/patologia , Neoplasias dos Seios Paranasais/patologia , Claudina-5 , Humanos , Imageamento por Ressonância Magnética , Microvasos , Papiloma Invertido/diagnóstico por imagem , Neoplasias dos Seios Paranasais/diagnóstico por imagem
20.
Zhonghua Yi Xue Za Zhi ; 99(43): 3417-3419, 2019 Nov 19.
Artigo em Chinês | MEDLINE | ID: mdl-31752470

RESUMO

Objective: To evaluate the value of CT in the differential diagnosis of Pseudomonas aeruginosa sinusitis and fungal ball in paranasal sinus caused by Aspergilus flavus. Methods: In this retrospective study, CT results of 74 cases of Pseudomonas aeruginosa sinusitis including 31 male cases and 43 female cases with age onset from 15 to 74 years old (mean±SD was 50±13) and 72 cases of fungal ball in paranasal sinus caused by Aspergilus flavus including 28 male cases and 44 female cases with age onset from 25 to 78 years old (mean±SD was 53±15) at Beijing Tongren Hospital confirmed by histopathology were enrolled from January 2013 to May 2017. The CT characteristics of the two groups of cases were compared using χ(2) test, and P<0.05 was considered statistically significant. Results: Soft tissue opacification of the involved paranasal sinus was found on CT in each case of the two groups. There were significant differences in the rate of single sinus involvement (44.6% and 90.3% respectively), the incidence of lesion associated with maxillary sinus (91.9% and 70.8% respectively), ethmoid sinus (41.9% and 2.8% respectively), frontal sinus (29.7% and 0 respectively), calcification (50.0% and 72.2% respectively), and the enlargement of maxillary sinus opening (13.2% and 35.3% respectively), in addition to the central calcification (83.8% and 59.6% respectively) between the two groups (all P<0.05). However, the incidence of sphenoid sinus involvement (32.4% and 34.7% respectively), bone sclerosis (56.8% and 62.5% respectively) or destruction(18.9% and 16.7% respectively) were not found different between the two groups (P>0.05). Conclusion: Though the CT findings are similar between the two diseases such as soft tissue opacification of the involved paranasal sinus with calcification and bone sclerosis or destruction, there are still a few characteristics on CT in differentiating the one from the other. The involvement of multi-sinuses, maxillary sinus, ethmoid sinus and frontal sinus, the central calcification are more common in the Pseudomonas aeruginosa sinusitis. However, the CT features including single sinus involvement, calcification and enlargement of maxillary sinus opening, can be seen more often in the fungal ball in paranasal sinus caused by Aspergilus flavus.


Assuntos
Seios Paranasais , Sinusite/diagnóstico por imagem , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Pseudomonas/complicações , Pseudomonas aeruginosa , Estudos Retrospectivos , Sinusite/etiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
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