Algoritmo de Indicação de Equipamento Coletor para Estomias / Algorithm for Indication of Collector Equipment for Stomas / Algoritmo para la Indicación de Equipos Colectores para Estomas

Objetivo:Relatar a experiência de uma equipe de enfermeiros estomaterapeutas na construção de um algoritmo para a indicação de equipamento coletor para estomias de eliminação. Método: Relato de experiência, do período de janeiro de 2018 a setembro de 2019, sobre o processo de construção de um algoritmo para indicação de equipamento coletor para estomias de eliminação. Resultados: A partir de determinadas características clínicas (parâmetros de avaliação) e da categorização dos equipamentos coletores (solução), foi desenvolvido um algoritmo para indicação de equipamento coletor para estomias de eliminação. Conclusão: Espera-se que esse instrumento possa auxiliar os enfermeiros na sua prática profissional quanto à escolha do equipamento coletor e na construção de protocolos clínicos.

Objective:To report the experience of a team of enterostomal therapists in the construction of an algorithm for the indication of collecting equipment for elimination stomas. Method: Experience report, from January 2018 to September 2019, on the process of building an algorithm to indicate collecting equipment for elimination stomas. Results: Based on certain clinical characteristics (assessment parameters) and the categorization of collecting equipment (solution), an algorithm was developed to indicate collecting equipment for elimination stomas. Conclusion: It is expected that this instrument can help nurses in their professional practice regarding the choice of collecting equipment and the construction of clinical protocols.

Objetivo:Relatar la experiencia de un equipo de enfermeros estomaterapeutas en la construcción de un algoritmo para la indicación de equipos recolectores para estomas de eliminación. Método: Informe de experiencia, de enero de 2018 a septiembre de 2019, sobre el proceso de construcción de un algoritmo para indicar equipos colectores para estomas de eliminación. Resultado: A partir de ciertas características clínicas (parámetros de evaluación) y la categorización de los equipos colectores (solución), se desarrolló un algoritmo para indicar equipos colectores para estomas de eliminación. Conclusión: Se espera que este instrumento pueda ayudar a los enfermeros en su práctica profesional en cuanto a la elección de equipos de recolección y la construcción de protocolos clínicos.

El hombre perfecto / I am your person

La fantasía que impera en este film plantea la ilusión de encontrar un ser complementario que se adapte a nuestras preferencias y nos haga plenos. "Mi algoritmo está diseñado para hacerte feliz" dice el humanoide. Ilusión de que alguien tendría la posibilidad de ser complementario, de saber exactamente lo que el otro requiere. Estamos en las antípodas de la famosa fórmula de Lacan:" (Le Séminaire, Encore, 1975) "No hay relación sexual" (o sea, no hay complementariedad). No habría resto, el sujeto no estaría atravesado por la castración simbólica. La IA compite con Zeus. La fantasía del Uno, organismo previo a la separación del andrógino por parte de Zeus, se podría materializar con la IA

The fantasy that prevails in this film, raises the illusion of finding a complementary being that adapts to our preferences and makes us full. "My algorithm is designed to make you happy," says the humanoid. Illusion that someone would have the possibility of being complementary, of knowing exactly what the other requires. We are at the antipodes of Lacan's famous formula: "(Le Séminaire, Encore, 1975) "There is no sexual intercourse" (that is, there is no complementarity). There would be no rest, the subject would not be pierced by symbolic castration. AI competes with Zeus. The fantasy of the One, an organism prior to the separation of the androgynous by Zeus, could materialize with AI.

Sex Determination by the Machine Learning Algorithms Through Using Morphometric Measurements of the Carpal, Metacarpal, and Phalangeal Bones / Determinación del Sexo Mediante Algoritmos de Aprendizaje Automático Mediante el Uso de Mediciones Morfométricas de los Huesos del Carpo, el Metacarpo y las Falanges

SUMMARY: In the study, it was aimed to predict sex from hand measurements using machine learning algorithms (MLA). Measurements were made on MR images of 60 men and 60 women. Determined parameters; hand length (HL), palm length (PL), hand width (HW), wrist width (EBG), metacarpal I length (MIL), metacarpal I width (MIW), metacarpal II length (MIIL), metacarpal II width (MIIW), metacarpal III length (MIIL), metacarpal III width (MIIIW), metacarpal IV length (MIVL), metacarpal IV width (MIVW), metacarpal V length (MVL), metacarpal V width (MVW), phalanx I length (PILL), measured as phalanx II length (PIIL), phalanx III length (PIIL), phalanx IV length (PIVL), phalanx V length (PVL). In addition, the hand index (HI) was calculated. Logistic Regression (LR), Random Forest (RF), Linear Discriminant Analysis (LDA), K-nearest neighbour (KNN) and Naive Bayes (NB) were used as MLAs. In the study, the KNN algorithm's Accuracy, SEN, F1 and Specificity ratios were determined as 88 %. In this study using MLA, it is understood that the highest accuracy belongs to the KNN algorithm. Except for the hand's MIIW, MIIIW, MIVW, MVW, HI variables, other variables were statistically significant in terms of sex difference.

En el estudio, el objetivo era predecir el sexo a partir de mediciones manuales utilizando algoritmos de aprendizaje automático (MLA). Las mediciones se realizaron en imágenes de RM de 60 hombres y 60 mujeres. Parámetros determinados; longitud de la mano (HL), longitud de la palma (PL), ancho de la mano (HW), ancho de la muñeca (EBG), longitud del metacarpiano I (MIL), ancho del metacarpiano I (MIW), longitud del metacarpiano II (MIIL), ancho del metacarpiano II (MIIW), longitud del metacarpiano III (MIIL), ancho del metacarpiano III (MIIIW), longitud del metacarpiano IV (MIVL), ancho del metacarpiano IV (MIVW), longitud del metacarpiano V (MVL), ancho del metacarpiano V (MVW), longitud de la falange I (PILL), medido como longitud de la falange II (PIIL), longitud de la falange III (PIIL), longitud de la falange IV (PIVL), longitud de la falange V (PVL). Además, se calculó el índice de la mano (HI). Regresión logística (LR), Random Forest (RF), Análisis discriminante lineal (LDA), K-vecino más cercano (KNN) y Naive Bayes (NB) se utilizaron como MLA. En el estudio, las proporciones de precisión, SEN, F1 y especificidad del algoritmo KNN se determinaron en un 88 %. En este estudio que utiliza MLA, se entiende que la mayor precisión pertenece al algoritmo KNN. Excepto por las variables MIIW, MIIIW, MIVW, MVW, HI de la mano, otras variables fueron estadísticamente significativas en términos de diferencia de sexo.

Experiencia en la introducción de resultados científicos desde la formación doctoral / Experience in the introduction of scientific results from the doctoral training i: en

Durante estos años, condicionados por los efectos de una pandemia y la situación económica global, la incorporación oportuna de los resultados científico-técnicos es necesidad y responsabilidad de la comunidad científica. En este trabajo se expone una experiencia en la introducción de resultados científicos desde la formación doctoral, dirigida al área de la atención inicial al paciente con traumatismo maxilofacial. La importancia de esta práctica radica en los aportes social, científico y profesional y en la formación de recursos humanos para lograr la transformación y el mejoramiento de la realidad.

During these years, conditioned by the effects of a pandemic and the global economic situation, the opportune incorporation of the scientific technical results is necessity and responsibility of scientific community. An experience in the introduction of scientific results from the doctoral training, directed to the area of initial care to the patient with maxillofacial traumatism, is presented in this work. The importance of this practice resides in the social, scientific, professional contributions and in the formation of human resources to achieve the transformation and improvement of reality.

Análise da generalização de algoritmos de machine learning e suas aplicações na otimização de decisões em saúde / Generalization analysis of machine learning algorithms and their applications in optimizing health decisions

A utilização de algoritmos de inteligência artificial tem crescido rapidamente nos últimos anos, aumentando o seu potencial de aplicação em saúde pública. Algoritmos de machine learning (ML) são capazes de auxiliar na predição de desfechos complexos e na tornada de decisões por parte dos profissionais da área. da. saúde. Esta tese tem como objetivo analisar a capacidade de generalização dos algoritmos na área da saúde e aplicar modelos de ML para predições utilizando dados tabulares frequentemente coletados nos sistemas de saúde. A tese será defendida sob a forma de três artigos científicos. O primeiro artigo realizou uma revisão sistemática da literatura sobre a capacidade de generalização de modelos de ML em saúde. Os resultados indicaram que, apesar de ainda limitada, a literatura sobre generalização em saúde está crescendo nos últimos anos em parte como uma demanda das próprias revistas científicas. O segundo artigo desenvolveu e avaliou a performance da validação externa de um algoritmo de ML no contexto da predição de risco de mortalidade neonatal. O modelo foi desenvolvido utilizando Extreme Gradient Boosting (XGB) em dados de São Paulo de 2012 a 2015, incluindo 807.932 nascidos vivos e 5.518 óbitos neonatais. Foi realizada a validação externa do algoritmo em 1.161 municípios brasileiros, incluindo todas as capitais de estado para o ano ele 2016, totalizando 2.848.052 nascidos vivos e 23.948 óbitos neonatais. Os resultados mostraram que os municípios que ofertam estruturas de maior complexidade obtiveram uma performance similar ou mesmo superior ao modelo base desenvolvido com dados do município de São Paulo. No terceiro e último artigo desta tese, foi realizada uma análise da aplicação da técnica de generalização conhecida como transfer learning nos dados da Rede IACOV-BR para predizer óbito entre pacientes internados por Covid-19 usando dados de prontuário de 16.236 pacientes de 18 hospitais brasileiros coletados no primeiro trimestre de 2020 durante o início da pandemia de Covid-19 no Brasil. A abordagem desse artigo propôs uma comparação entre uma nova solução capaz de predizer o progresso clínico dos pacientes com Covid- 19 versus a abordagem já aplicada para predições tabulares em saúde. Os resultados indicam que apesar de promissora, a técnica de transfer learning convencional não se mostrou superior aos resultados de performance obtidos localmente com os algoritmos de boosting utilizados para dados tabulares. Os resultados desta tese apontam para a importância da generalização dos algoritmos de i\IL em saúde, ao mesmo tempo que os desafios técnicos ainda persistem em relação à manutenção da performance preditiva nas diferentes localidades.

The use of artificial intelligence algorithms has significantly increased in recent years, increasing their potential for application in public health. ML algorithms (ML) can assist in the prediction of complex outcomes and in decision-making by healthcare professionals. This thesis aims to analyze the algorithmic generalization capability in healthcare and apply ML models for the prediction of health outcomes from tabular data frequently collected in healthcare systems. The thesis will be defended as three scientific articles. The first article conducted a systematic literature review on the generalization capability of ML models in healthcare. The results indicated that, although still limited, the literature on generalization in healthcare has been growing in recent years, in part as demand from journals themselves. The second article evaluated the performance of external validation of an ML algorithm in the context of predicting neonatal mortality risk. The model was developed using Extreme Gradient Boosting (XGB) on São Paulo data from 2012 to 2015, including 807,932 live births and 5,518 neonatal deaths. External validation of the algorithm was performed in 1,161 Brazilian municipalities, including all state capitals in 2016, totaling 2,848,052 live births and 23,948 neonatal deaths. The results showed that municipalities offering more complex structures obtained similar or even superior performance to the base model developed with data from the municipality of São Paulo. In the third and final article of this thesis, an analysis of the application of the generalization technique known as transfer learning was performed on IACOV-BR Network data to predict death from Covid-19 using medical record data from 16,236 patients from 18 Brazilian hospitals collected in the first quarter of 2020 during the early Covid-19 pandemic in Brazil. The results indicate that, although promising, the conventional transfer learning technique did not prove superior to locally obtained performance results with traditional boosting algorithms. The approach of this article proposed a comparison between a new solution for predicting the clinical progress of Covid-19 patients versus the approach already applied for tabular predictions in healthcare. The results of this thesis point to the importance of the generalization of ML algorithms in healthcare, while technical challenges persist regarding the maintenance of predictive performance in different locations.

A novel differential diagnosis algorithm for chronic lymphocytic leukemia using immunophenotyping with flow cytometry

Abstract Introduction The availability of a clinical decision algorithm for diagnosis of chronic lymphocytic leukemia (CLL) may greatly contribute to the diagnosis of CLL, particularly in cases with ambiguous immunophenotypes. Herein we propose a novel differential diagnosis algorithm for the CLL diagnosis using immunophenotyping with flow cytometry. Methods The hierarchical logistic regression model (Backward LR) was used to build a predictive algorithm for the diagnosis of CLL, differentiated from other lymphoproliferative disorders (LPDs). Results A total of 302 patients, of whom 220 (72.8%) had CLL and 82 (27.2%), B-cell lymphoproliferative disorders other than CLL, were included in the study. The Backward LR model comprised the variables CD5, CD43, CD81, ROR1, CD23, CD79b, FMC7, sIg and CD200 in the model development process. The weak expression of CD81 and increased intensity of expression in markers CD5, CD23 and CD200 increased the probability of CLL diagnosis, (p < 0.05). The odd ratio for CD5, C23, CD200 and CD81 was 1.088 (1.050 - 1.126), 1.044 (1.012 - 1.077), 1.039 (1.007 - 1.072) and 0.946 (0.921 - 0.970) [95% C.I.], respectively. Our model provided a novel diagnostic algorithm with 95.27% of sensitivity and 91.46% of specificity. The model prediction for 97.3% (214) of 220 patients diagnosed with CLL, was CLL and for 91.5% (75) of 82 patients diagnosed with an LPD other than CLL, was others. The cases were correctly classified as CLL and others with a 95.7% correctness rate. Conclusions Our model highlighting 4 markers (CD81, CD5, CD23 and CD200) provided high sensitivity and specificity in the CLL diagnosis and in distinguishing of CLL among other LPDs.

Particularités du cancer du larynx chez le sujet jeune / Epidemiological and clinical predictive factors of success in septoplasty: Study of 250 patients

Discuter à travers une étude descriptive ainsi qu'une revue de la littérature, les particularités cliniques, démographiques et pronostiques des patients de moins de 45 ans, ayant un cancer du larynx. Materiels et Methodes: Il s'agit d'une étude rétrospective descriptive portant sur des patients atteints d'un cancer du larynx, âgés de moins de 45 ans suivis dans le service d'ORL et de chirurgie cervico-faciale du CHU Habib Bourguiba Sfax durant la période s'étendant de 1989 à 2018. Resultats: Nous avons trouvé 31 patients avec une prédominance masculine. Un cancer dans la famille a été trouvé dans 16,12% des cas sans corrélation statistique avec le stade avancé de la maladie. Une importante intoxication tabagique a été trouvée (96%). Trois patients avaient une laryngite chronique et un patient une papillomatose laryngée avec des lésions de dysplasie. Les motifs de consultation étaient dominés par la dysphonie (87%). La maladie a été classée en stades avancés dans 70% des cas. Le traitement chirurgical était préconisé chez 87% des patients et la préservation fonctionnelle chez 38,7%. Le taux de survie globale et sans maladie étaient respectivement, à un an de 96% et 84%, à 3 ans de 87% et 76%, et à 5 ans de 77% et 75% Conclusion: Notre travail n'a pas permis de retenir de différence en termes de données cliniques, de l'évolution de la maladie, de l'algorithme thérapeutique ni du pronostic entre les jeunes patients et les plus âgés

Construction and evaluation of an artificial intelligence-based risk prediction model for death in patients with nasopharyngeal cancer / 南方医科大学学报

OBJECTIVE@#To screen the risk factors for death in patients with nasopharyngeal carcinoma (NPC) using artificial intelligence (AI) technology and establish a risk prediction model.@*METHODS@#The clinical data of NPC patients obtained from SEER database (1973-2015). The patients were randomly divided into model building and verification group at a 7∶3 ratio. Based on the data in the model building group, R software was used to identify the risk factors for death in NPC patients using 4 AI algorithms, namely eXtreme Gradient Boosting (XGBoost), Decision Tree (DT), Least absolute shrinkage and selection operator (LASSO) and random forest (RF), and a risk prediction model was constructed based on the risk factor identified. The C-Index, decision curve analysis (DCA), receiver operating characteristic (ROC) curve and calibration curve (CC) were used for internal validation of the model; the data in the validation group and clinical data of 96 NPC patients (collected from First Affiliated Hospital of Bengbu Medical College) were used for internal and external validation of the model.@*RESULTS@#The clinical data of a total of 2116 NPC patients were included (1484 in model building group and 632 in verification group). Risk factor screening showed that age, race, gender, stage M, stage T, and stage N were all risk factors of death in NPC patients. The risk prediction model for NPC-related death constructed based on these factors had a C-index of 0.76 for internal evaluation, an AUC of 0.74 and a net benefit rate of DCA of 9%-93%. The C-index of the model in internal verification was 0.740 with an AUC of 0.749 and a net benefit rate of DCA of 3%-89%, suggesting a high consistency of the two calibration curves. In external verification, the C-index of this model was 0.943 with a net benefit rate of DCA of 3%-97% and an AUC of 0.851, and the predicted value was consistent with the actual value.@*CONCLUSIONS@#Gender, age, race and TNM stage are risk factors of death of NPC patients, and the risk prediction model based on these factors can accurately predict the risks of death in NPC patients.

Application of extended reality technology for real-time navigation in clinical operation / 南方医科大学学报

OBJECTIVE@#To explore the application of extended reality (XR) technology in clinical surgeries for improving the success rate of surgeries.@*METHODS@#To assist the surgeons to better understand the location, size and geometric shape of the lesions and reduce potential radiation exposure in minimally invasive surgical navigation based on two-dimensional images, we constructed three-dimensional models based on CT data and used XR technology to achieve intraoperative navigation. An improved quaternion method was used to improve the accuracy of electromagnetic positioning, with which the system error of positioning accuracy was reduced to below 2 mm. A 5G network was used to optimize the server GPU programming algorithm, and real-time video stream coding strategy and network design were adopted to reduce data transmission jam and delay in the remote surgery network, which achieved an average delay of less than 60 ms. A Gaussian distribution deformation model was used to simulate collision detection and stress deformation of the tissues to achieve a tactile perception effect.@*RESULTS AND CONCLUSION@#The intraoperative navigation system based on XR technology allowed more accurate determination of the location of the lesions, effectively reduced the surgical risk, and avoided the risk of intraoperative radiation exposure. The low latency and high fidelity of 5G network achieved real-time interaction during the surgery to provide a technical basis for multi-terminal remote cooperative surgery. The combination of force feedback technology and XR technology enables the surgeons to conduct deep immersion preoperative planning and virtual surgery to improve the success rate of surgery and shorten the learning curve.

Using machine learning algorithm to predict the risk of post-traumatic stress disorder among firefighters in Changsha / 中南大学学报(医学版)

OBJECTIVES@#Firefighters are prone to suffer from psychological trauma and post-traumatic stress disorder (PTSD) in the workplace, and have a poor prognosis after PTSD. Reliable models for predicting PTSD allow for effective identification and intervention for patients with early PTSD. By collecting the psychological traits, psychological states and work situations of firefighters, this study aims to develop a machine learning algorithm with the aim of effectively and accurately identifying the onset of PTSD in firefighters, as well as detecting some important predictors of PTSD onset.@*METHODS@#This study conducted a cross-sectional survey through convenient sampling of firefighters from 20 fire brigades in Changsha, which were evenly distributed across 6 districts and Changsha County, with a total of 628 firefighters. We used the synthetic minority oversampling technique (SMOTE) to process data sets and used grid search to finish the parameter tuning. The predictive capability of several commonly used machine learning models was compared by 5-fold cross-validation and using the area under the receiver operating characteristic curve (ROC-AUC), accuracy, precision, recall, and F1 score.@*RESULTS@#The random forest model achieved good performance in predicting PTSD with an average AUC score at 0.790. The mean accuracy of the model was 90.1%, with an F1 score of 0.945. The three most important predictors were perseverance, forced thinking, and reflective deep thinking, with weights of 0.165, 0.158, and 0.152, respectively. The next most important predictors were employment time, psychological power, and optimism.@*CONCLUSIONS@#PTSD onset prediction model for Changsha firefighters constructed by random forest has strong predictive ability, and both psychological characteristics and work situation can be used as predictors of PTSD onset risk for firefighters. In the next step of the study, validation using other large datasets is needed to ensure that the predictive models can be used in clinical setting.

Quality of Images Reconstructed by Deep Learning Reconstruction Algorithm for Head and Neck CT Angiography at 100 kVp / 中国医学科学院学报

Objective To evaluate the impact of deep learning reconstruction algorithm on the image quality of head and neck CT angiography (CTA) at 100 kVp. Methods CT scanning was performed at 100 kVp for the 37 patients who underwent head and neck CTA in PUMC Hospital from March to April in 2021.Four sets of images were reconstructed by three-dimensional adaptive iterative dose reduction (AIDR 3D) and advanced intelligent Clear-IQ engine (AiCE) (low,medium,and high intensity algorithms),respectively.The average CT value,standard deviation (SD),signal-to-noise ratio (SNR),and contrast-to-noise ratio (CNR) of the region of interest in the transverse section image were calculated.Furthermore,the four sets of sagittal maximum intensity projection images of the anterior cerebral artery were scored (1 point:poor,5 points:excellent). Results The SNR and CNR showed differences in the images reconstructed by AiCE (low,medium,and high intensity) and AIDR 3D (all P<0.01).The quality scores of the image reconstructed by AiCE (low,medium,and high intensity) and AIDR 3D were 4.78±0.41,4.92±0.27,4.97±0.16,and 3.92±0.27,respectively,which showed statistically significant differences (all P<0.001). Conclusion AiCE outperformed AIDR 3D in reconstructing the images of head and neck CTA at 100 kVp,being capable of improving image quality and applicable in clinical examinations.

Based on CT radiomics model for predicting the response to first-line chemotherapy of diffuse large B-cell lymphoma / 中华肿瘤杂志

Objective: To investigate the potential value of CT Radiomics model in predicting the response to first-line chemotherapy in diffuse large B-cell lymphoma (DLBCL). Methods: Pre-treatment CT images and clinical data of DLBCL patients treated at Shanxi Cancer Hospital from January 2013 to May 2018 were retrospectively analyzed and divided into refractory patients (73 cases) and non-refractory patients (57 cases) according to the Lugano 2014 efficacy evaluation criteria. The least absolute shrinkage and selection operator (LASSO) regression algorithm, univariate and multivariate logistic regression analyses were used to screen out clinical factors and CT radiomics features associated with efficacy response, followed by radiomics model and nomogram model. Receiver operating characteristic (ROC) curve, calibration curve and clinical decision curve were used to evaluate the models in terms of the diagnostic efficacy, calibration and clinical value in predicting chemotherapy response. Results: Based on pre-chemotherapy CT images, 850 CT texture features were extracted from each patient, and 6 features highly correlated with the first-line chemotherapy effect of DLBCL were selected, including 1 first order feature, 1 gray level co-occurence matrix, 3 grey level dependence matrix, 1 neighboring grey tone difference matrix. Then, the corresponding radiomics model was established, whose ROC curves showed AUC values of 0.82 (95% CI: 0.76-0.89) and 0.73 (95% CI: 0.60-0.86) in the training and validation groups, respectively. The nomogram model, built by combining validated clinical factors (Ann Arbor stage, serum LDH level) and CT radiomics features, showed an AUC of 0.95 (95% CI: 0.90-0.99) and 0.91 (95% CI: 0.82-1.00) in the training group and the validation group, respectively, with significantly better diagnostic efficacy than that of the radiomics model. In addition, the calibration curve and clinical decision curve showed that the nomogram model had good consistency and high clinical value in the assessment of DLBCL efficacy. Conclusion: The nomogram model based on clinical factors and radiomics features shows potential clinical value in predicting the response to first-line chemotherapy of DLBCL patients.

Machine and deep learning-based clinical characteristics and laboratory markers for the prediction of sarcopenia / 中华医学杂志(英文版)

BACKGROUND@#Sarcopenia is an age-related progressive skeletal muscle disorder involving the loss of muscle mass or strength and physiological function. Efficient and precise AI algorithms may play a significant role in the diagnosis of sarcopenia. In this study, we aimed to develop a machine learning model for sarcopenia diagnosis using clinical characteristics and laboratory indicators of aging cohorts.@*METHODS@#We developed models of sarcopenia using the baseline data from the West China Health and Aging Trend (WCHAT) study. For external validation, we used the Xiamen Aging Trend (XMAT) cohort. We compared the support vector machine (SVM), random forest (RF), eXtreme Gradient Boosting (XGB), and Wide and Deep (W&D) models. The area under the receiver operating curve (AUC) and accuracy (ACC) were used to evaluate the diagnostic efficiency of the models.@*RESULTS@#The WCHAT cohort, which included a total of 4057 participants for the training and testing datasets, and the XMAT cohort, which consisted of 553 participants for the external validation dataset, were enrolled in this study. Among the four models, W&D had the best performance (AUC = 0.916 ± 0.006, ACC = 0.882 ± 0.006), followed by SVM (AUC =0.907 ± 0.004, ACC = 0.877 ± 0.006), XGB (AUC = 0.877 ± 0.005, ACC = 0.868 ± 0.005), and RF (AUC = 0.843 ± 0.031, ACC = 0.836 ± 0.024) in the training dataset. Meanwhile, in the testing dataset, the diagnostic efficiency of the models from large to small was W&D (AUC = 0.881, ACC = 0.862), XGB (AUC = 0.858, ACC = 0.861), RF (AUC = 0.843, ACC = 0.836), and SVM (AUC = 0.829, ACC = 0.857). In the external validation dataset, the performance of W&D (AUC = 0.970, ACC = 0.911) was the best among the four models, followed by RF (AUC = 0.830, ACC = 0.769), SVM (AUC = 0.766, ACC = 0.738), and XGB (AUC = 0.722, ACC = 0.749).@*CONCLUSIONS@#The W&D model not only had excellent diagnostic performance for sarcopenia but also showed good economic efficiency and timeliness. It could be widely used in primary health care institutions or developing areas with an aging population.@*TRIAL REGISTRATION@#Chictr.org, ChiCTR 1800018895.

A method for sensitivity analysis of deviation factor for geometric correction of cone-beam CT system / 南方医科大学学报

OBJECTIVE@#To propose a sensitivity test method for geometric correction position deviation of cone-beam CT systems.@*METHODS@#We proposed the definition of center deviation and its derivation. We analyzed the influence of the variation of the three-dimensional spatial center of the steel ball point, the projection center and the size of the steel ball point on the deviation of geometric parameters and the reconstructed image results by calculating the geometric correction parameters based on the Noo analytical method using the FDK reconstruction algorithm for image reconstruction.@*RESULTS@#The radius of the steel ball point was within 3 mm. The deviation of the center of the calibration parameter was within the order of magnitude and negligible. A 10% Gaussian perturbation of a single pixel in the 3D spatial coordinates of the steel ball point produced a deviation of about 3 pixel sizes, while the same Gaussian perturbation of the 2D projection coordinates of the steel ball point produced a deviation of about 2 pixel sizes.@*CONCLUSION@#The geometric correction is more sensitive to the deviation generated by the three-dimensional spatial coordinates of the steel ball point with limited sensitivity to the deviation generated by the two-dimensional projection coordinates of the steel ball point. The deviation sensitivity of a small diameter steel ball point can be ignored.

Diffusion tensor field estimation based on 3D U-Net and diffusion tensor imaging model constraint / 南方医科大学学报

OBJECTIVE@#To propose a diffusion tensor field estimation network based on 3D U-Net and diffusion tensor imaging (DTI) model constraint (3D DTI-Unet) to accurately estimate DTI quantification parameters from a small number of diffusion-weighted (DW) images with a low signal-to-noise ratio.@*METHODS@#The input of 3D DTI-Unet was noisy diffusion magnetic resonance imaging (dMRI) data containing one non-DW image and 6 DW images with different diffusion coding directions. The noise-reduced non-DW image and accurate diffusion tensor field were predicted through 3D U-Net. The dMRI data were reconstructed using the DTI model and compared with the true value of dMRI data to optimize the network and ensure the consistency of the dMRI data with the physical model of the diffusion tensor field. We compared 3D DTI-Unet with two DW image denoising algorithms (MP-PCA and GL-HOSVD) to verify the effect of the proposed method.@*RESULTS@#The proposed method was better than MP-PCA and GL-HOSVD in terms of quantitative results and visual evaluation of DW images, diffusion tensor field and DTI quantification parameters.@*CONCLUSION@#The proposed method can obtain accurate DTI quantification parameters from one non-DW image and 6 DW images to reduce image acquisition time and improve the reliability of quantitative diagnosis.

Sinogram interpolation combined with unsupervised image-to-image translation network for CT metal artifact correction / 南方医科大学学报

OBJECTIVE@#To propose a framework that combines sinogram interpolation with unsupervised image-to-image translation (UNIT) network to correct metal artifacts in CT images.@*METHODS@#The initially corrected CT image and the prior image without artifacts, which were considered as different elements in two different domains, were input into the image transformation network to obtain the corrected image. Verification experiments were carried out to assess the effectiveness of the proposed method using the simulation data, and PSNR and SSIM were calculated for quantitative evaluation of the performance of the method.@*RESULTS@#The experiment using the simulation data showed that the proposed method achieved better results for improving image quality as compared with other methods, and the corrected images preserved more details and structures. Compared with ADN algorithm, the proposed algorithm improved the PSNR and SSIM by 2.4449 and 0.0023 when the metal was small, by 5.9942 and 8.8388 for images with large metals, and by 8.8388 and 0.0130 when both small and large metals were present, respectively.@*CONCLUSION@#The proposed method for metal artifact correction can effectively remove metal artifacts, improve image quality, and preserve more details and structures on CT images.