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2.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 724-728, 2022.
Article in Chinese | WPRIM | ID: wpr-957201

ABSTRACT

Objective:To explore the added value of time-activity curve (TAC) and target-to-background ratio (TBR) obtained by 18F-FDG total-body PET/CT dynamic imaging in the diagnosis of liver malignant tumors. Methods:From December 2019 to October 2021, 109 patients (65 males, 44 females; age (59.3±9.3) years) with hepatocellular carcinoma (HCC; n=27), intrahepatic cholangiocarcinoma (ICC; n=61) and colorectal cancer with liver metastasis (CRLM; n=21) who underwent 60 min 18F-FDG total-body PET/CT dynamic imaging in Zhongshan Hospital, Fudan University were retrospectively enrolled. Dynamic PET/CT images were divided into perfusion-weighted (PW) phase and metabolism-weighted (MW) phase. The arterial phase was defined as the 15 s after the abdominal aorta peak frame at PW. TACs at MW were divided into three types as Graph A, Graph B and Graph C. One-way analysis of variance was used to compare difference of TBR 30/60 among groups. ROC curve analysis was used to evaluate diagnostic effectiveness. Results:With hypervascularity as the diagnostic standard of HCC, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 66.7%(18/27), 75.6%(59/78), 48.6%(18/37) and 86.8%(59/68), respectively. With Graph B as the diagnostic standard of HCC, the sensitivity, specificity, PPV and NPV were 44.4%(12/27), 85.4%(70/82), 50.0%(12/24) and 82.4%(70/85), respectively. The TBR 30/60 of HCC, ICC and CRLM was 0.38±0.19, 0.49±0.18 and 0.64±0.20 respectively ( F=10.89, P<0.001). When the cut-off value of TBR 30/60 was 0.43, the AUC of distinguishing HCC from ICC and CRLM was 0.72, with the sensitivity and specificity of 70.5%(55/78) and 65.2%(15/23). When the cut-off value of TBR 30/60 was 0.64, the AUC of distinguishing ICC from CRLM was 0.71, with the sensitivity and specificity of 61.9%(13/21) and 82.5%(47/57). Conclusion:TAC graph types and TBR 30/60 obtained by total-body PET/CT dynamic imaging display potential value for differentiation between hepatic tumor types.

3.
Chinese Journal of Ocular Fundus Diseases ; (6): 89-92, 2022.
Article in Chinese | WPRIM | ID: wpr-934276

ABSTRACT

At present, artificial intelligence (AI) has been widely used in the diagnosis and treatment of various ophthalmological diseases, but there are still many problems. Due to the lack of standardized test sets, gold standards, and recognized evaluation systems for the accuracy of AI products, it is difficult to compare the results of multiple studies. When it comes to the field of image generation, we hardly have an efficient approach to evaluating research results. In clinical practice, ophthalmological AI research is often out of touch with actual clinical needs. The requirements for the quality and quantity of clinical data put more burden on AI research, limiting the transformation of AI studies. The prediction of systemic diseases based on fundus images is making progressive advancement. However, the lack of interpretability of the research lower the acceptance. Ophthalmology AI research also suffer from ethical controversy due to unconstructed regulations and regulatory mechanisms, concerns on patients' privacy and data security, and the risk of aggravating the unfairness of medical resources.

4.
Radiol. bras ; 54(2): 87-93, Jan.-Apr. 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1155241

ABSTRACT

Abstract Objective: To determine whether the radiomic features of lung lesions on computed tomography correlate with overall survival in lung cancer patients. Materials and Methods: This was a retrospective study involving 101 consecutive patients with malignant neoplasms confirmed by biopsy or surgery. On computed tomography images, the lesions were submitted to semi-automated segmentation and were characterized on the basis of 2,465 radiomic variables. The prognostic assessment was based on Kaplan-Meier analysis and log-rank tests, according to the median value of the radiomic variables. Results: Of the 101 patients evaluated, 28 died (16 dying from lung cancer), and 73 were censored, with a mean overall survival time of 1,819.4 days (95% confidence interval [95% CI]: 1,481.2-2,157.5). One radiomic feature (the mean of the Fourier transform) presented a difference on Kaplan-Meier curves (p < 0.05). A high-risk group of patients was identified on the basis of high values for the mean of the Fourier transform. In that group, the mean survival time was 1,465.4 days (95% CI: 985.2-1,945.6), with a hazard ratio of 2.12 (95% CI: 1.01-4.48). We also identified a low-risk group, in which the mean of the Fourier transform was low (mean survival time of 2,164.8 days; 95% CI: 1,745.4-2,584.1). Conclusion: A radiomic signature based on the Fourier transform correlates with overall survival, representing a prognostic biomarker for risk stratification in patients with lung cancer.


Resumo Objetivo: Associar características radiômicas de lesões pulmonares em imagens de tomografia computadorizada com a sobrevida global de pacientes com câncer de pulmão. Materiais e Métodos: Estudo retrospectivo composto por 101 pacientes consecutivos com neoplasia maligna confirmada por biópsia/cirurgia. As lesões foram semiautomaticamente segmentadas e caracterizadas por 2.465 variáveis radiômicas. A avaliação prognóstica foi baseada na análise de Kaplan-Meier e no teste log-rank, de acordo com a mediana dos valores das variáveis. Resultados: Vinte e oito pacientes faleceram (16 por câncer de pulmão) e 73 foram censurados, com tempo médio de sobrevida de 1.819,4 dias (intervalo de confiança 95% [IC 95%]: 1.481,2-2.157,5). Uma característica radiômica (média de Fourier) apresentou diferença nas curvas de Kaplan-Meier (p < 0,05). Um grupo de pacientes de maior risco foi identificado a partir de valores altos da variável: sobrevida de 1.465,4 dias (IC 95%: 985,2-1.945,6) e razão de risco de 2,12 (IC 95%: 1,01-4,48). Um grupo de menor risco foi identificado a partir de valores baixos da variável (sobrevida de 2.164,8 dias; IC 95%: 1.745,4-2.584,1). Conclusão: Este estudo apresentou uma assinatura radiômica em imagens de tomografia computadorizada, baseada na transformada de Fourier, correlacionada com a sobrevida global de pacientes com câncer de pulmão, representando assim um biomarcador prognóstico.

5.
Chinese Journal of Orthopaedic Trauma ; (12): 1003-1007, 2021.
Article in Chinese | WPRIM | ID: wpr-910078

ABSTRACT

The process of bone healing is absolutely complicated and affected by a wide variety of factors. The quality of bone healing directly determines management approaches. Therefore, it is crucial to evaluate accurately outcomes of bone healing. The assessments of bone healing mostly used in current clinical practice are a combination of clinical manifestations and X-ray examination while computed tomography (CT) and ultrasound may be applied alternatively for particular parts and populations. As understanding of bone healing process and bone biomechanical structure is deepening in recent years, both traditional and novel assessments of bone healing have been well refined. This review will expound on the advantages, disadvantages and clinical indications of various assessments, as well as their future development trends, to provide useful information for clinicians.

6.
Chinese Journal of Primary Medicine and Pharmacy ; (12): 1291-1295, 2021.
Article in Chinese | WPRIM | ID: wpr-909207

ABSTRACT

Objective:To investigate the imaging manifestations and diagnostic significance of multislice spiral CT angiography for aortic intramural hematoma.Methods:Forty-three patients with aortic intramural hematoma who received digital subtraction angiography or multislice spiral CT angiography in Yiwu Central Hospital from November 2017 to September 2018 were included in this study. The misdiagnosis rate and image quality were compared between the two imaging examination methods.Results:The misdiagnosis rate of digital subtraction angiography was 6.98% (3/43) and that of multislice spiral CT angiography was 4.65% (2/43). There was no significant difference in the misdiagnosis rate between the two methods ( P > 0.05). The numbers of patients receiving multislice spiral CT angiography with grade III image quality ( n = 4) and grade IV image quality ( n = 2) were lower than those of patients receiving digital subtraction angiography ( χ2 = 3.957 and 4.074, both P < 0.05). There were no significant difference in the numbers of patients with grade I and II image quality between the two methods (both P > 0.05). Multislice spiral CT angiography showed that among 43 patients, 18 patients had non-ulcerative aortic wall hematoma, 25 patients had ulcerative aortic wall hematoma. Among patients with aortic wall hematoma, 14 patients had moderate or more amount of pleural effusion, with the average thickness of hematoma tissue of 11.42 mm, the maximum diameter of the involved ascending aorta of 56 mm, and the maximum diameter of the involved descending aorta of 44 mm. Conclusion:Multislice spiral CT angiography is superior to digital subtraction angiography in the diagnosis of aortic wall hematoma because it provides clearer images, which can help better present lesion changes.

7.
Chinese Journal of Primary Medicine and Pharmacy ; (12): 1035-1040, 2021.
Article in Chinese | WPRIM | ID: wpr-909169

ABSTRACT

Objective:To investigate the value of radiomic features of computed tomography (CT) images in the diagnosis of invasive pulmonary adenocarcinoma appearing as part-solid ground-glass nodules.Methods:The clinical data of 100 part-solid ground-glass nodules from 88 patients with pulmonary adenocarcinoma confirmed by pathological diagnosis who received surgical treatment in Taizhou Tumor Hospital, China between February 2016 and April 2019 were retrospectively analyzed. Among these 100 part-solid ground-glass nodules, 56 from 53 patients were diagnosed as invasive pulmonary adenocarcinoma and 44 from 35 patients as non-invasive pulmonary adenocarcinoma. A set of regular risk factors and visually-assessed qualitative CT imaging features were compared with the radiomic features using logistic regression analysis. Three diagnostic models, i.e., a basis model using the clinical risk factors and qualitative CT features, a radiomics model using significant radiomic features, and a nomogram model combining all significant features, were established and their diagnostic efficacy was compared based on receiver operating characteristic (ROC) curves. Decision curve analysis was performed for the nomogram model to explore its potential clinical benefit.Results:Multiple logistic regression analysis showed that three qualitative CT imaging features (pleural traction ( P = 0.006), solid component size ( P = 0.045) and solid component proportion ( P = 0.020)) and quantitative Rad score ( P = 0.046) were significantly correlated with invasive pulmonary adenocarcinoma. The adjusted ratios were 7.189, 0.075, 194.786 and 2.016, respectively. The diagnostic nomogram model based on these four features showed that the area under the ROC curve (AUC) was 0.903 (95% CI: 0.845, 0.975). The diagnostic nomogram model showed a significantly higher performance (AUC = 0.903) in differentiating invasive pulmonary adenocarcinoma from non-invasive pulmonary adenocarcinoma than either the basis model (AUC = 0.853, P = 0.000) or the radiomics model (AUC = 0.769, P < 0.001). Decision curve analysis indicated a potential benefit of using such a nomogram model in clinical diagnosis. Conclusion:Quantitative radiomic features provide additional information regarding clinically-assessed qualitative features for differentiating invasive pulmonary adenocarcinoma from non-invasive pulmonary adenocarcinoma appearing as ground-glass nodules, and a diagnostic nomogram model including all these significant features may be clinically useful in preoperative strategy planning.

9.
Article in English | LILACS, BBO | ID: biblio-1135544

ABSTRACT

Abstract Objective: To obtain the standardized values of individuals of Malaysian Malay and Chinese for further relevant research, such as treatment planning and aesthetical considerations. Material and Methods: In this retrospective study, 440 (305 were Malays and 135 were Chinese) standardized lateral cephalometric radiographs of orthodontic patients selected through simple random sampling are profiled using Holdaway's analysis. The independent t-test was used to assess the disparities in race and gender. The significant level was p<0.05. Results: Significant differences were found between the Malays and Chinese in their skeletal profile convexity, superior sulcus depth, inferior sulcus to the H line and nose prominence. Between Malay females and males, there are significant differences in superior sulcus depth, soft tissue subnasale to H line, basic upper lip thickness, upper lip thickness and nose prominence. Between Chinese males and females, there were differences in their skeletal profile convexity, upper lip to H line, basic upper lip thickness and upper lip thickness. Conclusion: The findings demonstrated the difference between standardized norms and the unique profiles of Malaysian Malays and Chinese. There are significant gender disparities in the soft tissue cephalometric measurements among Malaysian Malay and Chinese subjects.


Subject(s)
Humans , Male , Female , Orthodontics , Radiographic Image Interpretation, Computer-Assisted/instrumentation , China , Cephalometry/instrumentation , Lip , Malaysia , Retrospective Studies , Data Interpretation, Statistical , Asian People
10.
Radiol. bras ; 52(5): 293-298, Sept.-Oct. 2019. graf
Article in English | LILACS | ID: biblio-1040949

ABSTRACT

Abstract Objective: To perform a quantitative analysis of the brain volume of elderly individuals in a population-based sample. Materials and Methods: This was a radiological assessment and voxel-based quantitative analysis, with surface alignment, of 525 magnetic resonance imaging scans of individuals between 60 and 103 years of age who participated in the Saúde, Bem-estar e Envelhecimento (Health, Well-being, and Aging) study in the city of São Paulo, Brazil. Results: We noted a median rate of reduction in total brain volume of 2.4% per decade after 60 years of age. Gray and white matter both showed volume reductions with age. The total brain volume/intracranial brain volume ratio differed between males and females. Conclusion: We have corroborated the findings of studies conducted in the United States and Europe. The total brain volume/intracranial brain volume ratio is higher in men, representing a potential bias for the conventional radiological assessment of atrophy, which is typically based on the evaluation of the cerebrospinal fluid spaces.


Resumo Objetivo: Analisar, quantitativamente, o volume cerebral de idosos em uma amostra de base populacional em São Paulo. Materiais e Métodos: O estudo é uma avaliação radiológica e análise quantitativa baseada em voxel com alinhamento de superfície de 525 imagens de ressonância magnética de participantes de uma coorte de idosos (SABE - Saúde, Bem-estar e Envelhecimento) em São Paulo, Brasil, com idades de 60 a 103 anos, dos dois sexos. Resultados: Observamos redução média do volume cerebral total de 2,4% por década após os 60 anos de idade. A redução de volume ocorreu na substância cinzenta e na substância branca com a idade. A relação entre volume cerebral intracraniano e volume cerebral total diferiu entre homens e mulheres. Conclusão: Nós reproduzimos os achados de estudos prévios em populações americanas e europeias. A relação entre volume intracraniano e volume cerebral é maior em homens, o que pode representar fonte de viés na avaliação de atrofia radiológica convencional, já que essa avaliação é usualmente baseada em análise de espaços liquóricos intracranianos.

11.
Clinical and Molecular Hepatology ; : 390-399, 2019.
Article in English | WPRIM | ID: wpr-785650

ABSTRACT

BACKGROUND/AIMS: A risk prediction model for the development of hepatocellular carcinoma (HCC) from indeterminate nodules detected on computed tomography (CT) (Rad(CT) score) in patients with chronic hepatitis B (CHB)-related cirrhosis was proposed. We validated this model for indeterminate nodules on magnetic resonance imaging (MRI).METHODS: Between 2013 and 2016, Liver Imaging Reporting and Data System (LI-RADS) 2/3 nodules on MRI were detected in 99 patients with CHB. The Rad(CT) score was calculated.RESULTS: The median age of the 72 male and 27 female subjects was 58 years. HCC history and liver cirrhosis were found in 47 (47.5%) and 44 (44.4%) patients, respectively. The median Rad(CT) score was 112. The patients with HCC (n=41, 41.4%) showed significantly higher Rad(CT) scores than those without (median, 119 vs. 107; P=0.013); the Chinese university-HCC and risk estimation for HCC in CHB (REACH-B) scores were similar (both P>0.05). Arterial enhancement, T2 hyperintensity, and diffusion restriction on MRI were not significantly different in the univariate analysis (all P>0.05); only the Rad(CT) score significantly predicted HCC (hazard ratio [HR]=1.018; P=0.007). Multivariate analysis showed HCC history was the only independent HCC predictor (HR=2.374; P=0.012). When the subjects were stratified into three risk groups based on the Rad(CT) score (<60, 60–105, and >105), the cumulative HCC incidence was not significantly different among them (all P>0.05, log-rank test).CONCLUSIONS: HCC history, but not Rad(CT) score, predicted CHB-related HCC development from LI-RADS 2/3 nodules. New risk models optimized for MRI-defined indeterminate nodules are required.


Subject(s)
Female , Humans , Male , Asian People , Carcinoma, Hepatocellular , Diffusion , Fibrosis , Hepatitis B , Hepatitis B, Chronic , Hepatitis, Chronic , Incidence , Information Systems , Liver , Liver Cirrhosis , Liver Neoplasms , Magnetic Resonance Imaging , Multivariate Analysis , Radiographic Image Interpretation, Computer-Assisted , Risk Assessment
12.
Chinese Journal of Primary Medicine and Pharmacy ; (12): 123-128, 2019.
Article in Chinese | WPRIM | ID: wpr-733915

ABSTRACT

Pancreatic cancer is a malignant tumor,and the clinical manifestations are not characteristic,so it is difficult to diagnose at an early stage, and it has a poor prognosis. Image technology has been widely used in clinical,with mature technology,and the application of image technology not only confined to the image display,but also has become a hot spot of research, including dynamic contrast enhancement magnetic resonance imaging (DCE-MRI),intravoxel incoherent motion ( IVIM),CT perfusion imaging,which could analyze quantitatively the permeability and microvascular of lesions,to improve the sensitivity of diagnosis,and to assess quantitatively the effect of drugs,radiation and chemotherapy.

13.
Acta ortop. bras ; 26(4): 240-243, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-973558

ABSTRACT

ABSTRACT Objective: To demonstrate whether or not there is a correlation between the risk factors for gonarthrosis and the radiographic classification of Ahlbäck. Methods: We studied patients with primary gonarthrosis attended at the knee outpatient clinic of the General Hospital of Vila Penteado during their routine visit. We collected data on patient age (years), weight (kg), height (meters), body mass index (BMI = patient weight/height2), personal history of hypertension or diabetes mellitus (positive or negative), sedentarism (physical activity less than three times per week, 30 minutes per session), functional demand (how many blocks walked weekly), time of onset of symptoms (in years) and laterality or bilaterality. The data were correlated with the Ahlbäck classification applied to the radiographs performed at the time of the consultation. Results: A sample of 108 patients was studied. We did not find an association between the Ahlbäck classification and the patient's age, smoking, sedentary lifestyle, laterality, number of blocks walked per week, diabetes mellitus, and sex; however, a positive association was observed in hypertensive patients as well as a weak correlation with height and weight of the patient and moderate correlation with BMI. Conclusion: The Ahlbäck classification is unrelated to most of the risk factors for primary gonarthrosis. Level of evidence III, Case-control study.


RESUMO Objetivo: Demonstrar se existe ou não correlação entre os fatores de risco de gonartrose e a classificação radiográfica de Ahlbäck. Métodos: Estudamos pacientes com gonartrose primária, assistidos no ambulatório de joelho do Hospital Geral de Vila Penteado em sua consulta de rotina. Foram coletados dados referentes a idade do paciente (anos), peso do paciente (kg), altura (metros), índice de massa corporal (IMC= peso do paciente/altura2), antecedente pessoal de hipertensão ou diabetes mellitus (positivo ou negativo), sedentarismo (se pratica atividade física menos de três vezes por semana, 30 minutos por sessão), demanda funcional (quantas quadras caminha semanalmente), tempo do início dos sintomas (em anos) e lateralidade ou bilateralidade. Os dados foram correlacionados com a classificação de Ahlbäck aplicada às radiografias realizadas no momento da consulta. Resultados: Uma amostra de 108 pacientes foi estudada. Não encontramos associação entre a classificação de Ahlbäck e a idade do paciente, tabagismo, sedentarismo, lateralidade, quantidade de quadras percorridas por semana, diabetes mellitus e sexo do paciente, porém verificou-se associação positiva em pacientes hipertensos e correlação fraca com altura e peso do paciente e correlação moderada com IMC. Conclusão: A classificação de Ahlbäck não apresenta relação com a maioria dos fatores de risco de gonartrose primária. Nível de evidência III, Estudo caso-controle.

14.
Rev. bras. cir. plást ; 33(1): 115-118, jan.-mar. 2018. ilus
Article in English, Portuguese | LILACS | ID: biblio-883647

ABSTRACT

Os princípios para uma rinoplastia bem-sucedida incluem consulta e planejamento pré-operatório e uma análise clínica abrangente que defina as metas da cirurgia. Mais recentemente, a digitalização e a impressão doméstica em 3 dimensões tornaram-se disponíveis. O objetivo deste estudo é descrever um método de digitalização em 3 dimensões e de impressão doméstica da anatomia real do paciente para ser usada como ajuda intraoperatória. Nós apresentamos uma forma de uso desta tecnologia no transoperatório, auxiliando o cirurgião a comparar os resultados obtidos após suas manobras, verificar a sua adesão ao plano cirúrgico previamente estabelecido e melhorar a sua tomada de decisão durante a cirurgia. Em conclusão, a aplicação da impressão doméstica em 3 dimensões demonstra um efeito positivo sobre o tratamento de alterações estéticas do nariz.


The principles for a successful rhinoplasty include preoperative consultation and planning, as well as a comprehensive clinical analysis and defining rhinoplasty goals. Three-dimensional domestic scanning and printing have recently become available. We sought to objectively describe this method as an intraoperative aid in patients' anatomy. This method can be used trans-operatively to help surgeons compare the results of his or her technique, check adherence to the surgical plan, and improve his or her surgical decision-making. We found that the application of 3-dimensional printing had a positive effect on the treatment of patients with aesthetic nose disorders.


Subject(s)
Humans , History, 21st Century , Rhinoplasty , Image Processing, Computer-Assisted , Image Interpretation, Computer-Assisted , Plastic Surgery Procedures , Imaging, Three-Dimensional , Bioprinting , Inventions , Rhinoplasty/instrumentation , Rhinoplasty/methods , Image Processing, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted/methods , Image Interpretation, Computer-Assisted/instrumentation , Image Interpretation, Computer-Assisted/methods , Plastic Surgery Procedures/methods , Imaging, Three-Dimensional/instrumentation , Imaging, Three-Dimensional/methods , Bioprinting/instrumentation , Bioprinting/methods , Inventions/standards , Inventions/ethics
15.
Radiol. bras ; 51(1): 1-7, Jan.-Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-896165

ABSTRACT

Abstract Objective: This study aimed to explore the functional connectivity of the default mode network (DMN) in crack-cocaine users, in comparison with that observed in age-matched non-drug-using controls. Materials and Methods: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug-using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were defined by spatial independent component analysis and seed-based correlation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. Results: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack-cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between specific brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was significantly greater in the crack-cocaine users than in the controls. Conclusion: The results suggest that selective extrinsic network connectivity of the DMN related to motor and executive function is impaired during crack-cocaine addiction.


Resumo Objetivo: Este estudo teve como objetivo explorar a conectividade funcional da rede de modo padrão em usuários de crack-cocaína comparando-a a controles não usuários da mesma faixa etária. Materiais e Métodos: Usuários de crack-cocaína internados em abstinência por pelo menos quatro semanas e controles não usuários pareados por idade foram submetidos a ressonância magnética funcional em estado de repouso, enquanto descansavam com os olhos fechados. Depois do pré-processamento de dados, a rede de modo padrão foi definida por análise espacial de componentes independentes e análise de correlação baseada em sementes, por regiões de interesse centradas no córtex cingulado anterior ventral e no córtex cingulado posterior. Resultados: A conectividade funcional analisada por componentes independentes não foi diferente entre os usuários de crack- cocaína e os controles pareados por idade. No entanto, a análise de correlação baseada em sementes à procura de uma conectividade funcional métrica única entre regiões específicas do cérebro mostrou uma negatividade significativamente maior da conectividade entre o córtex cingulado anterior ventral e o lóbulo parietal superior esquerdo, quando comparada a controles pareados por idade. Conclusão: Os resultados sugerem que conectividades extrínsecas seletivas da rede de modo padrão relacionadas a funções motoras e executivas podem estar comprometidas na dependência de crack-cocaína.

16.
Chinese Journal of Medical Imaging ; (12): 441-446,451, 2017.
Article in Chinese | WPRIM | ID: wpr-614929

ABSTRACT

Purpose At present,morphological observation and CT value measurement were mainly used to evaluate ground-glass nodule (GGN),and there was no effective image feature-quantization evaluation method.Therefore,in this study,a follow-up quantization analysis was conducted on GGN within 2 years using texture feature analysis method to confirm reasonable GGN follow-up time.Materials and Methods Baseline and highresolution CT images of 100 GGN follow-up patients were retrospectively analyzed.They were assigned into three groups,3 months follow-up (group A),6 to 12 months follow-up (group B) and 2 years follow-up (group C).For each group,using firstly founded GGN image as baseline,GGN texture features (including energy,contrast,autocorrelation,inverse difference moment and entropy) were analyzed.Results There were 1 case of narrowed nodules in group A,1 case of increased nodules and 1 case of narrowed nodules in group B,and 4 cases of increased nodules in group C,2 of which showed density differences.There was no significant change in shape,density and size of the remaining nodules.There were no significant differences in texture features (energy,contrast,autocorrelation,deficit,entropy) among group A,group B and group C (P>0.05).Conclusion Texture feature analysis can quantitatively evaluate the change of GGN attribute characteristics,and as a GGN follow-up quantitative tool,it can guide patients to choose reasonable follow-up mode.

17.
International Journal of Cerebrovascular Diseases ; (12): 39-44, 2016.
Article in Chinese | WPRIM | ID: wpr-486161

ABSTRACT

Objective To investigate w hether the iterative reconstruction (iDose 4 ) technique improves imaging quality of the low-radiation-dose w hole brain CT perfusion (CTP). Methods Thirty-five consecutive patients w ith clinical y suspected ischemic stroke w ere col ected. Bril iance 256 iCT w as used to perform low-radiation-dose w hole brain CTP, and the filtered back projection (FBP) and iDose 4 algorithm w ere used to conduct image reconstruction. The noise and signal to noise ratio of the 2 kinds of reconstruction algorithms, as w el as the imaging quality of each parameter map w ere compared. Results The effective dose of the w hole brain CTP w as 2.2 mSv. Compared w ith FBP, the noise of each region of interest in the iDose4 Tmax map was decreased significantly ( P<0.05) and the signal to noise ratio was increased significantly (P<0.05). The imaging quality scores (median, interquartile range) reconstructed by FPB group w ere significantly low er than by iDose 4 for cerebral blood flow (CBF) map ( 5.00 [3.00-6.00]vs. 6.00 [5.00-6.00]; Z= -2.784, P=0.005), cerebral blood volume (CBV) map ( 6.00 [5.00-6.00] vs. 6.00 [6.00-7.00]; Z= -3.674, P<0.001), and mean transit time (MTT) map (4.00 [3.00-5.00] vs. 5.00 [4.00-6.00]; Z=3.394, P=0.001). The proportions of the poor quality in CBF map ( 34.3%vs. 11.4%;χ2 =7.036, P=0.030), CBV map (11.4%vs.2.9%; χ2 =7.485, P=0.024 ) and MTT map (28.6%vs.11.4%;χ2 =5.318, P=0.070) reconstructed by FBP w ere significantly higher than by iDose 4 . Conclusions The iDose4 technique may improve imaging quality of low er-radiation-dose CTP.

18.
Journal of Korean Medical Science ; : 457-462, 2016.
Article in English | WPRIM | ID: wpr-85713

ABSTRACT

The purpose was to present mean breast density of Korean women according to age using fully automated volumetric assessment. This study included 5,967 screening normal or benign mammograms (mean age, 46.2 +/- 9.7; range, 30-89 years), from cancer-screening program. We evaluated mean fibroglandular tissue volume, breast tissue volume, volumetric breast density (VBD), and the results were 53.7 +/- 30.8 cm3, 383.8 +/- 205.2 cm3, and 15.8% +/- 7.3%. The frequency of dense breasts and mean VBD by age group were 94.3% and 19.1% +/- 6.7% for the 30s (n = 1,484), 91.4% and 17.2% +/- 6.8% for the 40s (n = 2,706), 72.2% and 12.4% +/- 6.2% for the 50s (n = 1,138), 44.0% and 8.6% +/- 4.3% for the 60s (n = 89), 39.1% and 8.0% +/- 3.8% for the 70s (n = 138), and 39.1% and 8.0% +/- 3.5% for the 80s (n = 12). The frequency of dense breasts was higher in younger women (n = 4,313, 92.3%) than older women (n = 1,654, 59.8%). Mean VBD decreased with aging or menopause, and was about 16% for 46-year-old-Korean women, much higher than in other countries. The proportion of dense breasts sharply decreases in Korean women between 40 and 69 years of age.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Aging , Asian People , Automation , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Image Processing, Computer-Assisted , Mammography , Menopause , Republic of Korea
19.
China Journal of Orthopaedics and Traumatology ; (12): 903-909, 2016.
Article in Chinese | WPRIM | ID: wpr-230371

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the meaning of pedicle exposure technique for screw fixation on atlas with the vertebral groove height less than 4 mm by using reconstructive computed tomography.</p><p><b>METHODS</b>From April 2015 to June 2015, 84 pedicles of 51 patients with groove heights less than 4 mm were studied by digital reconstruction respectively. Parameters of atlas pedicle screw fixation were measured.</p><p><b>RESULTS</b>Among the 51 cases, the vertebral groove height was (3.28±0.51) mm. Lateral mass heights, lateral mass widths and the transition area heights between lateral mass and posterior arch were fit for 3.5 mm screw implanting. Ideal pedicle screw trajectory lengths from 0° to 15° (0°, 5°, 10°, 15°) were (27.36±1.81), (27.01±1.68), (27.07±1.75), (27.48±1.72) mm, exposed trajectory lengths from 0° to 15°(0°, 5°, 10°, 15°) were(23.44±1.79), (23.87±1.84), (24.58±1.89), (25.56±2.01) mm, trajectory length of lateral mass was (20.78±2.05) mm. The mean CT values on 5 sections through pedicle trajectory and lateral mass trajectory were (701.89±141.48) HU and (599.11±137.33) HU, respectively. There were no significant differences between ideal pedicle trajectory lengths from 0° to 15°(>0.05). Exposed trajectory lengths was significantly increased accompanying with medial angles increasing (<0.05), and was longer than trajectory lengths of lateral mass (<0.05). CT value of pedicle screws was higher than CT value of lateral mass screws significantly (<0.01).</p><p><b>CONCLUSIONS</b>Screws can be implanted in atlas with vertebral groove height less than 4 mm by using pedicle exposure technique. Few trajectory lengths will be sacrificed with favorable pull out strength due to adequate bone mass purchased.</p>

20.
Chinese Journal of Digestion ; (12): 223-225, 2013.
Article in Chinese | WPRIM | ID: wpr-437061

ABSTRACT

Objective To analyze endoscopic ultrasonography (EUS) image of esophageal granular cell tumor (GCT) by computer image analysis software,and to explore its diagnostic and differential diagnostic value.Methods Eight esophageal GCT and eight leiomyomas confirmed by pathological and immunohistochemical examination were collected,mean gray value and gray value standard deviation of EUS image of the leisons were analyzed by computer image analysis software.The comparison of two groups was analyzed by t test.Results The endoscopic and ultrasound images of esophageal GCT and leiomyomas were similar.The mean gray value of EUS image of esophageal GCT and esophageal leiomyomas was 67.51 and 51.76,the difference was statistically significant (t=2.225,P=0.043).However,there was no significant difference in the standard deviation of gray value (13.54 vs 13.12,t=0.225,P=0.825).Conclusion The accuracy of GCT diagnosed by EUS could be increased by comparing the gray values of EUS images of esophageal GCT and leiomyomas.

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