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1.
Journal of Central South University(Medical Sciences) ; (12): 385-392, 2021.
Artigo em Inglês | WPRIM | ID: wpr-880671

RESUMO

OBJECTIVES@#Glioma is the most common intracranial primary tumor in central nervous system. Glioma grading possesses important guiding significance for the selection of clinical treatment and follow-up plan, and the assessment of prognosis. This study aims to explore the feasibility of logistic regression model based on radiomics to predict glioma grading.@*METHODS@#Retrospective analysis was performed on 146 glioma patients with confirmed pathological diagnosis from January, 2012 to December, 2018. A total of 41 radiomics features were extracted from contrast-enhanced T@*RESULTS@#A total of 5 imaging features selected by LASSO were used to establish a logistic regression model for predicting glioma grading. The model showed good discrimination with AUC value of 0.919. Hosmer-Lemeshow test showed no significant difference between the calibration curve and the ideal curve (@*CONCLUSIONS@#The logistic regression model using radiomics exhibits a relatively high accuracy for predicting glioma grading, which may serve as a complementary tool for preoperative prediction of giloma grading.


Assuntos
Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Modelos Logísticos , Imageamento por Ressonância Magnética , Curva ROC , Estudos Retrospectivos
2.
Chinese Journal of Radiology ; (12): 792-798, 2020.
Artigo em Chinês | WPRIM | ID: wpr-868346

RESUMO

Objective:To explore the diagnostic efficacy of nomogram based on multi-parameter MRI for assessment of bowel fibrosis in patients with Crohn disease(CD).Methods:The clinical and imaging data of CD patients diagnosed by surgical histopathology in the First Affiliated Hospital of Sun Yat-sen University from June 2015 to March 2018 were prospectively collected. All the patients underwent conventional MRI and diffusion kurtosis imaging(DKI) within 2 weeks before surgery. Patients who underwent surgery between June 2015 and September 2017 were included in the model building group, and those who underwent surgery between October 2017 and March 2018 were included in the model validation group. We measured the apparent diffusion coefficient(ADC) from monoexponential model of diffusion-weighted imaging(DWI), apparent diffusional kurtosis(K app), and apparent diffusion for non-Gaussian distribution(D app) from non-Gaussian DKI model, and observed T 2WI signal intensity and enhancement pattern of the same segment. One to three intestinal specimens per patient were stained with Masson′s trichrome for the histological grading of fibrosis. Correlations between qualitative/quantitative MRI indexes and histological grades were evaluated using the Spearman rank test. Multivariate logistic regression analysis was performed to identify independent factors to be included into the nomogram for predicting the degree of bowel fibrosis and its diagnostic performance was assessed by internal and external validation. Results:A total of 40 CD patients were included, including 31 in the model construction group and 9 in the model verification group. A total of 81 intestinal specimens from 31 patients were graded as none-to-mild bowel fibrosis( n=32) and moderate-to-severe bowel fibrosis( n=49) according to a scoring system of fibrosis. In the training cohort, the K app value of moderate-to-severely fibrotic bowel walls was significantly higher than that of none-to-mildly fibrotic bowel walls, and the D appand ADC values of moderate-to-severely fibrotic bowel walls were significantly lower than those of none-to-mildly fibrotic bowel walls( Z=-5.999, -4.521 and -3.893; P<0.001). There was no significant difference in T 2WI signal intensity or enhancement pattern between these two groups(χ2=1.571 and 0.103; P>0.05). Moderate and mild correlations of histological fibrosis grades with K appand D app( r=0.721 and -0.483; P<0.001), and a mild correlation with ADC( r=-0.445, P<0.001) were found. Independent factors derived from multivariate logistic regression analysis to predict the degree of bowel fibrosis were K app and D app. Internal and external validation revealed good performance of the nomogram with concordance index of 0.901(95% confidence interval, 0.824-0.978) and 1.000, respectively, for differentiating none-to-mild from moderate-to-severe fibrosis. Conclusion:The DKI-based nomogram can be used to evaluate the bowel fibrosis in CD patients and provides a visual and simple prediction method for clinic.

3.
Journal of Central South University(Medical Sciences) ; (12): 576-581, 2020.
Artigo em Inglês | WPRIM | ID: wpr-827382

RESUMO

OBJECTIVES@#To explore and analyze the epidemic features of coronavirus disease 2019 (COVID-19) in Hunan Province from January 21, 2020 to March 14, 2020, as well as to investigate the COVID-19 epidemics in each city of Hunan Province.@*METHODS@#The epidemic data was obtained from the official website of Hunan Province's Health Commission. The data of each city of Hunan Province was analyzed separately. Spatial distribution of cumulative confirmed COVID-19 patients and the cumulative occurrence rate was drawn by ArcGIS software for each city in Hunan Province. Some regional indexes were also compared with that in the whole country.@*RESULTS@#The first patient was diagnosed in January 21, sustained patient growth reached its plateau in around February 17. Up to March 14, the cumulative confirmed COVID-19 patients stopped at 1 018. The cumulative occurrence rate of COVID-19 patients was 0.48 per 0.1 million person. The number of cumulative severe patients was 150 and the number of cumulative dead patients was 4. The mortality rate (0.39%) and the cure rate (99.6%) in Hunan Province was significantly lower and higher respectively than the corresponding average rate in the whole country (0.90% and 96.2%, Hubei excluded). The first 3 cities in numbers of the confirmed patients were Changsha, Yueyang, and Shaoyang. While sorted by the cumulative occurrence rate, the first 3 cities in incidence were Changsha, Yueyang, and Zhuzhou.@*CONCLUSIONS@#The epidemic of COVID-19 spread out smoothly in Hunan Province. The cities in Hunan Province implement anti-disease strategies based on specific situations on their own and keep the epidemic in the range of controllable.


Assuntos
Humanos , Betacoronavirus , China , Epidemiologia , Cidades , Epidemiologia , Infecções por Coronavirus , Epidemiologia , Mortalidade , Pandemias , Pneumonia Viral , Epidemiologia , Mortalidade
4.
Journal of Central South University(Medical Sciences) ; (12): 1315-1322, 2018.
Artigo em Chinês | WPRIM | ID: wpr-813132

RESUMO

To explore the feasibility and efficacy of artificial neural network for differentiating high-grade glioma and low-grade glioma using image information.
 Methods: A total of 130 glioma patients with confirmed pathological diagnosis were selected retrospectively from 2012 to 2017. Forty one imaging features were extracted from each subjects based on 2-dimension magnetic resonance T1 weighted imaging with contrast-enhancement. An artificial neural network model was created and optimized according to the performance of feature selection. The training dataset was randomly selected half of the whole dataset, and the other half dataset was used to verify the performance of the neural network for glioma grading. The training-verification process was repeated for 100 times and the performance was averaged.
 Results: A total of 5 imaging features were selected as the ultimate input features for the neural network. The mean accuracy of the neural network for glioma grading was 90.32%, with a mean sensitivity at 87.86% and a mean specificity at 92.49%. The area under the curve of receiver operating characteristic curve was 0.9486.
 Conclusion: As a technique of artificial intelligence, neural network can reach a relatively high accuracy for the grading of glioma and provide a non-invasive and promising computer-aided diagnostic process for the pre-operative grading of glioma.


Assuntos
Humanos , Neoplasias Encefálicas , Diagnóstico por Imagem , Patologia , Glioma , Diagnóstico por Imagem , Patologia , Imageamento por Ressonância Magnética , Gradação de Tumores , Redes Neurais de Computação , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Chinese Journal of Otorhinolaryngology Head and Neck Surgery ; (12): 573-579, 2017.
Artigo em Chinês | WPRIM | ID: wpr-809143

RESUMO

Objective@#The present study was carried out to explore the tone production ability of the Mandarin-speaking children with cochlear implants (CI) by using an artificial neural network model and to examine the potential contributing factors underlining their tone production performance. The results of this study might provide useful guidelines for post-operative rehabilitation processes of pediatric CI users.@*Methods@#Two hundred and seventy-eight prelingually deafened children who received unilateral CI participated in this study. As controls, 170 similarly-aged children with normal hearing (NH) were recruited. A total of 36 Chinese monosyllabic words were selected as the tone production targets. Vocal production samples were recorded and the fundamental frequency (F0) contour of each syllable was extracted using an auto-correlation algorithm followed by manual correction. An artificial neural network was created in MATLAB to classify the tone production. The relationships between tone production and several demographic factors were evaluated.@*Results@#Pediatric CI users produced Mandarin tones much less accurately than did the NH children (58.8% vs. 91.5% correct). Tremendous variability in tone production performance existed among the CI children. Tones 2 and 3 were produced less accurately than tones 1 and 4 for both groups. For the CI group, all tones when in error tended to be judged as tone 1. The tone production accuracy was negatively correlated with age at implantation and positively correlated with CI use duration with correlation coefficients (r) of -0.215 (P=0.003) and 0.203 (P=0.005), respectively. Age was one of the determinants of tonal ability for NH children.@*Conclusions@#For children with severe to profound hearing loss, early implantation and persistent use of CI are beneficial to their tone production development. Artificial neural network is a convenient and reliable assessment tool for the development of tonal ability of hearing-impaired children who are in the rehabilitation processes that focus on speech and language expression.

6.
Journal of Clinical Otorhinolaryngology Head and Neck Surgery ; (24): 1111-1115, 2012.
Artigo em Chinês | WPRIM | ID: wpr-746962

RESUMO

OBJECTIVE@#To explore and analyze the clinical characteristics and treatment strategy of severe complications caused by esophageal foreign bodies.@*METHOD@#A retrospective study was carried out on 49 cases with foreign bodies in esophagus through careful analysis of their clinical data to explore the associated problems with etiology and therapy. Among this complications, there were cases of 13 periesophageal abscess, 20 cases of abscess in the neck, 11 cases of mediastinal abscess, 3 tracheoesophageal fistula, 1 case of aorta injury and 1 septicemia.@*RESULT@#Forty-eight (97.96%) of the patients recovered while one died.@*CONCLUSION@#Hard esophagoscopy under general anesthesia is the main therapeutic strategy to take out the esophageal foreign bodies. When it failed or severe complications such as perforation or others emerged, open surgery like lateral neck incision or thoracotomy supplemented with positive and timely supporting therapy are vital and essential.


Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Esôfago , Corpos Estranhos , Cirurgia Geral , Estudos Retrospectivos
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