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Rickettsia is the pathogen of Q fever, Brucella ovis is the pathogen of brucellosis, and both of them are Gram-negative bacteria which are parasitic in cells. The mixed infection of rickettsia and Brucella ovis is rarely reported in clinic. Early diagnosis and treatment are of great significance to the treatment and prognosis of brucellosis and Q fever. Here, we report a case of co-infection Rickettsia burneti and Brucella melitensis. The patient is a 49-year-old sheepherder, who was hospitalized with left forearm trauma. Three days after admission, the patient developed fever of 39.0°C, accompanied by sweating, fatigue, poor appetite and headache. Indirect immunofluorescence (IFA) was used to detect Rickettsia burneti IgM. After 72 hours of blood culture incubation, bacterial growth was detected in aerobic bottles, Gram-negative bacilli were found in culture medium smear, the colony was identified as Brucella melitensis by mass spectrometry. Patients were treated with doxycycline (100 mg bid, po) and rifampicin (600 mg qd, po) for 4 weeks. After treatment, the symptoms disappeared quickly, and there was no sign of recurrence or chronic infection. Q fever and Brucella may exist in high-risk practitioners, so we should routinely detect these two pathogens to prevent missed diagnosis.
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Brucelosis/complicaciones , Brucelosis/diagnóstico , Coinfección , Infecciones por Rickettsia/complicaciones , Infecciones por Rickettsia/diagnóstico , Brucella melitensis/fisiología , Doxiciclina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Rickettsia/fisiología , Rifampin/uso terapéutico , Resultado del TratamientoRESUMEN
Melanoma is a highly malignant and is a life-threatening disease with no effective treatment currently. This study aims to evaluate the significance of TUSC3, an endoplasmic reticulum stress (ERS)-inducible gene and explore its relationship with AKT/GSK3-ß/ß-catenin signalling pathway in melanoma cell WM451. We investigated TUSC3 expression in melanoma cell by qRT-PCR, CCK-8 and clonal formation assays were utilized to evaluate cell proliferation. Wound healing and transwell experiments detected cell migration and invasion. Flow cytometry detected the level of apoptosis. Western blot analysed MMP2, MMP9, p-AKT, p-GSK3-ß, ß-catenin and AKT, GSK3-ß, ERS-related proteins and apoptosis-related proteins in WM451 cells. The results revealed that TUSC3 was remarkably decreased in melanoma cell lines. Overexpression of TUSC3 significantly inhibits melanoma cell WM451 biological functions and promotes expression of ERS-related proteins in WM451 cells, increases ERS in WM451 cells by inhibiting AKT/GSK3-ß/ß-catenin pathway. These finding suggest that TUSC3 regulates biological functions of melanoma cells WM451 and increases ERS in melanoma cells WM451 via the inhibition of the AKT/GSK3-ß/ß-catenin signalling pathway. SIGNIFICANCE OF THE STUDY: Melanoma is a highly malignant and is a life-threatening disease with no effective treatment currently. Therefore, studying the molecular mechanism of melanoma occurrence and metastasis is essential for the treatment of melanoma. Meanwhile, mounting studies suggest that TUSC3 is considered to be closely associated with the development of various malignancies. TUSC3 regulates proliferation, migration and epithelial-to-mesenchymal transition, but the molecular mechanism of the tumour suppressor effects of TUSC3 on melanoma cells is not well understood. Our study demonstrates that TUSC3 inhibits biological function of melanoma cells and increases ERS in melanoma cells by inhibiting AKT/GSK3-ß/ß-catenin pathway. And this is expected to be a new target and method for the treatment of melanoma.
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Glucógeno Sintasa Quinasa 3/metabolismo , Melanoma/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Supresoras de Tumor/metabolismo , beta Catenina/metabolismo , Apoptosis , Movimiento Celular , Proliferación Celular , Células Cultivadas , Estrés del Retículo Endoplásmico , Humanos , Melanoma/patología , Proteínas de la Membrana/genética , Proteínas Supresoras de Tumor/genéticaRESUMEN
BACKGROUND The PCK1 gene encodes phosphoenolpyruvate carboxykinase (PEPCK), which has been shown have a role in metabolic events in hepatocellular carcinoma (HCC). This study aimed to investigate the role of the SHH gene and its encoded protein, sonic hedgehog (SHH), in two human hepatocellular carcinoma (HCC) cell lines. MATERIAL AND METHODS The human HCC cell lines Hep3B and SMMC-7721 were cultured. Cells were transfected with plasmids carrying specific SHH gene short-hairpin RNA (shRNA) and negative control (NC) shRNA. The effects of knockdown of expression levels of the SHH gene were studied on cell survival, cell apoptosis, the cell cycle, gluconeogenesis, and the expression of PCK1. Anchorage-independent growth, a characteristic of transformed cells, was detected by the colony formation assay. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot were performed 24 h after transfection. RESULTS Knockdown of expression levels of the SHH gene reduced cell proliferation and growth of HCC cells and induced cell apoptosis and G1 cell cycle arrest in both HCC cell lines. Knockdown of the SHH gene decreased the levels of glycolysis products and increased the production of glucose and reduced the phosphorylation of PI3K and Akt but induced the expression of PCK1. CONCLUSIONS Knockdown of the SHH gene reduced cell survival of HCC cells by increasing apoptosis, reducing cell proliferation, inducing G1 cell cycle arrest, and restoring gluconeogenesis, and was associated with the inhibition of the PI3K/Akt axis and induced the expression of PCK1.
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Carcinoma Hepatocelular/genética , Proteínas Hedgehog/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Fosfoenolpiruvato Carboxiquinasa (GTP)/genética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Puntos de Control de la Fase G1 del Ciclo Celular , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis , Proteínas Hedgehog/metabolismo , Células Hep G2 , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfoenolpiruvato Carboxiquinasa (ATP)/metabolismo , Fosfoenolpiruvato Carboxiquinasa (GTP)/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/fisiologíaAsunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Paniculitis , Humanos , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirugía , Carcinoma Ductal Pancreático/complicaciones , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/cirugía , Paniculitis/diagnóstico , Paniculitis/etiología , Paniculitis/patologíaAsunto(s)
Glucagonoma , Eritema Necrolítico Migratorio , Neoplasias Pancreáticas , Glucagonoma/complicaciones , Glucagonoma/diagnóstico , Glucagonoma/cirugía , Humanos , Eritema Necrolítico Migratorio/diagnóstico , Eritema Necrolítico Migratorio/etiología , Necrosis , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirugíaRESUMEN
OBJECTIVE: Optical Coherence Tomography (OCT) images can provide non-invasive visualization of fundus lesions; however, scanners from different OCT manufacturers largely vary from each other, which often leads to model deterioration to unseen OCT scanners due to domain shift. METHODS: To produce the T-styles of the potential target domain, an Orthogonal Style Space Reparameterization (OSSR) method is proposed to apply orthogonal constraints in the latent orthogonal style space to the sampled marginal styles. To leverage the high-level features of multi-source domains and potential T-styles in the graph semantic space, a Graph Adversarial Network (GAN) is constructed to align the generated samples with the source domain samples. To align features with the same label based on the semantic feature in the graph semantic space, Graph Semantic Alignment (GSA) is performed to focus on the shape and the morphological differences between the lesions and their surrounding regions. RESULTS: Comprehensive experiments have been performed on two OCT image datasets. Compared to state-of-the-art methods, the proposed method can achieve better segmentation. CONCLUSION: The proposed fundus lesion segmentation method can be trained with labeled OCT images from multiple manufacturers' scanners and be tested on an unseen manufacturer's scanner with better domain generalization. SIGNIFICANCE: The proposed method can be used in routine clinical occasions when an unseen manufacturer's OCT image is available for a patient.
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Algoritmos , Interpretación de Imagen Asistida por Computador , Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Fondo de Ojo , Bases de Datos Factuales , Enfermedades de la Retina/diagnóstico por imagenRESUMEN
OBJECTIVE: Multi-modal magnetic resonance (MR) image segmentation is an important task in disease diagnosis and treatment, but it is usually difficult to obtain multiple modalities for a single patient in clinical applications. To address these issues, a cross-modal consistency framework is proposed for a single-modal MR image segmentation. METHODS: To enable single-modal MR image segmentation in the inference stage, a weighted cross-entropy loss and a pixel-level feature consistency loss are proposed to train the target network with the guidance of the teacher network and the auxiliary network. To fuse dual-modal MR images in the training stage, the cross-modal consistency is measured according to Dice similarity entropy loss and Dice similarity contrastive loss, so as to maximize the prediction similarity of the teacher network and the auxiliary network. To reduce the difference in image contrast between different MR images for the same organs, a contrast alignment network is proposed to align input images with different contrasts to reference images with a good contrast. RESULTS: Comprehensive experiments have been performed on a publicly available prostate dataset and an in-house pancreas dataset to verify the effectiveness of the proposed method. Compared to state-of-the-art methods, the proposed method can achieve better segmentation. CONCLUSION: The proposed image segmentation method can fuse dual-modal MR images in the training stage and only need one-modal MR images in the inference stage. SIGNIFICANCE: The proposed method can be used in routine clinical occasions when only single-modal MR image with variable contrast is available for a patient.
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Algoritmos , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Procesamiento de Imagen Asistido por Computador/métodos , Próstata/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Páncreas/diagnóstico por imagenRESUMEN
BACKGROUND: Deep learning based optical coherence tomography (OCT) segmentation methods have achieved excellent results, allowing quantitative analysis of large-scale data. However, OCT images are often acquired by different devices or under different imaging protocols, which leads to serious domain shift problem. This in turn results in performance degradation of segmentation models. PURPOSE: Aiming at the domain shift problem, we propose a two-stage adversarial learning based network (TSANet) that accomplishes unsupervised cross-domain OCT segmentation. METHODS: In the first stage, a Fourier transform based approach is adopted to reduce image style differences from the image level. Then, adversarial learning networks, including a segmenter and a discriminator, are designed to achieve inter-domain consistency in the segmentation output. In the second stage, pseudo labels of selected unlabeled target domain training data are used to fine-tune the segmenter, which further improves its generalization capability. The proposed method was tested on cross-domain datasets for choroid or retinoschisis segmentation tasks. For choroid segmentation, the model was trained on 400 images and validated on 100 images from the source domain, and then trained on 1320 unlabeled images and tested on 330 images from target domain I, and also trained on 400 unlabeled images and tested on 200 images from target domain II. For retinoschisis segmentation, the model was trained on 1284 images and validated on 312 images from the source domain, and then trained on 1024 unlabeled images and tested on 200 images from the target domain. RESULTS: The proposed method achieved significantly improved results over that without domain adaptation, with improvement of 8.34%, 55.82% and 3.53% in intersection over union (IoU) respectively for the three test sets. The performance is better than some state-of-the-art domain adaptation methods. CONCLUSIONS: The proposed TSANet, with image level adaptation, feature level adaptation and pseudo-label based fine-tuning, achieved excellent cross-domain generalization. This alleviates the burden of obtaining additional manual labels when adapting the deep learning model to new OCT data.
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Procesamiento de Imagen Asistido por Computador , Retina , Tomografía de Coherencia Óptica , Retina/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Humanos , Aprendizaje Automático no Supervisado , Aprendizaje ProfundoRESUMEN
CT and MR are currently the most common imaging techniques for pancreatic cancer diagnosis. Accurate segmentation of the pancreas in CT and MR images can provide significant help in the diagnosis and treatment of pancreatic cancer. Traditional supervised segmentation methods require a large number of labeled CT and MR training data, which is usually time-consuming and laborious. Meanwhile, due to domain shift, traditional segmentation networks are difficult to be deployed on different imaging modality datasets. Cross-domain segmentation can utilize labeled source domain data to assist unlabeled target domains in solving the above problems. In this paper, a cross-domain pancreas segmentation algorithm is proposed based on Moment-Consistent Contrastive Cycle Generative Adversarial Networks (MC-CCycleGAN). MC-CCycleGAN is a style transfer network, in which the encoder of its generator is used to extract features from real images and style transfer images, constrain feature extraction through a contrastive loss, and fully extract structural features of input images during style transfer while eliminate redundant style features. The multi-order central moments of the pancreas are proposed to describe its anatomy in high dimensions and a contrastive loss is also proposed to constrain the moment consistency, so as to maintain consistency of the pancreatic structure and shape before and after style transfer. Multi-teacher knowledge distillation framework is proposed to transfer the knowledge from multiple teachers to a single student, so as to improve the robustness and performance of the student network. The experimental results have demonstrated the superiority of our framework over state-of-the-art domain adaptation methods.
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Retinopathy of prematurity (ROP) usually occurs in premature or low birth weight infants and has been an important cause of childhood blindness worldwide. Diagnosis and treatment of ROP are mainly based on stage, zone and disease, where the zone is more important than the stage for serious ROP. However, due to the great subjectivity and difference of ophthalmologists in the diagnosis of ROP zoning, it is challenging to achieve accurate and objective ROP zoning diagnosis. To address it, we propose a new key area location (KAL) system to achieve automatic and objective ROP zoning based on its definition, which consists of a key point location network and an object detection network. Firstly, to achieve the balance between real-time and high-accuracy, a lightweight residual heatmap network (LRH-Net) is designed to achieve the location of the optic disc (OD) and macular center, which transforms the location problem into a pixel-level regression problem based on the heatmap regression method and maximum likelihood estimation theory. In addition, to meet the needs of clinical accuracy and real-time detection, we use the one-stage object detection framework Yolov3 to achieve ROP lesion location. Finally, the experimental results have demonstrated that the proposed KAL system has achieved better performance on key point location (6.13 and 17.03 pixels error for OD and macular center location) and ROP lesion location (93.05% for AP50), and the ROP zoning results based on it have good consistency with the results manually labeled by clinicians, which can support clinical decision-making and help ophthalmologists correctly interpret ROP zoning, reducing subjective differences of diagnosis and increasing the interpretability of zoning results.
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Objective.Neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) present many similar clinical features. However, there are significant differences in the progression of nAMD and PCV. and it is crucial to make accurate diagnosis for treatment. In this paper, we propose a structure-radiomic fusion network (DRFNet) to differentiate PCV and nAMD in optical coherence tomography (OCT) images.Approach.The subnetwork (RIMNet) is designed to automatically segment the lesion of nAMD and PCV. Another subnetwork (StrEncoder) is designed to extract deep structural features of the segmented lesion. The subnetwork (RadEncoder) is designed to extract radiomic features from the segmented lesions based on radiomics. 305 eyes (155 with nAMD and 150 with PCV) are included and manually annotated CNV region in this study. The proposed method was trained and evaluated by 4-fold cross validation using the collected data and was compared with the advanced differentiation methods.Main results.The proposed method achieved high classification performace of nAMD/PCV differentiation in OCT images, which was an improvement of 4.68 compared with other best method.Significance. The presented structure-radiomic fusion network (DRFNet) has great performance of diagnosing nAMD and PCV and high clinical value by using OCT instead of indocyanine green angiography.
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Coroides , Vasculopatía Coroidea Polipoidea , Humanos , Coroides/irrigación sanguínea , Tomografía de Coherencia Óptica/métodos , Radiómica , Angiografía con Fluoresceína/métodos , Estudios RetrospectivosRESUMEN
BACKGROUND: Since May 2022, outbreaks of monkeypox have occurred in many countries around the world, and several cases have been reported in China. CASE SUMMARY: A 38-year-old man presented with a small, painless, shallow ulcer on the coronary groove for 8 d. One day after the rash appeared, the patient developed inguinal lymphadenopathy with fever. The patient had a history of male-male sexual activity and denied a recent history of travel abroad. Monkeypox virus was detected by quantitative polymerase chain reaction from the rash site and throat swab. Based on the epidemiological history, clinical manifestations and nucleic acid test results, the patient was diagnosed with monkeypox. CONCLUSION: Monkeypox is an emerging infectious disease in China. Monkeypox presenting as a chancre-like rash is easily misdiagnosed. Diagnosis can be made based on exposure history, clinical manifestations and nucleic acid test results.
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Objective. Corneal confocal microscopy (CCM) is a rapid and non-invasive ophthalmic imaging technique that can reveal corneal nerve fiber. The automatic segmentation of corneal nerve fiber in CCM images is vital for the subsequent abnormality analysis, which is the main basis for the early diagnosis of degenerative neurological systemic diseases such as diabetic peripheral neuropathy.Approach. In this paper, a U-shape encoder-decoder structure based multi-scale and local feature guidance neural network (MLFGNet) is proposed for the automatic corneal nerve fiber segmentation in CCM images. Three novel modules including multi-scale progressive guidance (MFPG) module, local feature guided attention (LFGA) module, and multi-scale deep supervision (MDS) module are proposed and applied in skip connection, bottom of the encoder and decoder path respectively, which are designed from both multi-scale information fusion and local information extraction perspectives to enhance the network's ability to discriminate the global and local structure of nerve fibers. The proposed MFPG module solves the imbalance between semantic information and spatial information, the LFGA module enables the network to capture attention relationships on local feature maps and the MDS module fully utilizes the relationship between high-level and low-level features for feature reconstruction in the decoder path.Main results. The proposed MLFGNet is evaluated on three CCM image Datasets, the Dice coefficients reach 89.33%, 89.41%, and 88.29% respectively.Significance. The proposed method has excellent segmentation performance for corneal nerve fibers and outperforms other state-of-the-art methods.
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Ojo , Cara , Almacenamiento y Recuperación de la Información , Fibras Nerviosas , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por ComputadorRESUMEN
BACKGROUND: Choroid neovascularization (CNV) has no obvious symptoms in the early stage, but with its gradual expansion, leakage, rupture, and bleeding, it can cause vision loss and central scotoma. In some severe cases, it will lead to permanent visual impairment. PURPOSE: Accurate prediction of disease progression can greatly help ophthalmologists to formulate appropriate treatment plans and prevent further deterioration of the disease. Therefore, we aim to predict the growth trend of CNV to help the attending physician judge the effectiveness of treatment. METHODS: In this paper, we develop a CNN-based method for CNV growth prediction. To achieve this, we first design a registration network to rigidly register the spectral domain optical coherence tomography (SD-OCT) B-scans of each subject at different time points to eliminate retinal displacements of longitudinal data. Then, considering the correlation of longitudinal data, we propose a co-segmentation network with a correlation attention guidance (CAG) module to cooperatively segment CNV lesions of a group of follow-up images and use them as input for growth prediction. Finally, based on the above registration and segmentation networks, an encoder-recurrent-decoder framework is developed for CNV growth prediction, in which an attention-based gated recurrent unit (AGRU) is embedded as the recurrent neural network to recurrently learn robust representations. RESULTS: The registration network rigidly registers the follow-up images of patients to the reference images with a root mean square error (RMSE) of 6.754 pixels. And compared with other state-of-the-art segmentation methods, the proposed segmentation network achieves high performance with the Dice similarity coefficients (Dsc) of 85.27%. Based on the above experiments, the proposed growth prediction network can play a role in predicting the future CNV morphology, and the predicted CNV has a Dsc of 83.69% with the ground truth, which is significantly consistent with the actual follow-up visit. CONCLUSION: The proposed registration and segmentation networks provide the possibility for growth prediction. In addition, accurately predicting the growth of CNV enables us to know the efficacy of the drug against individuals in advance, creating opportunities for formulating appropriate treatment plans.
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Coroides , Neovascularización Coroidal , Humanos , Coroides/patología , Tomografía de Coherencia Óptica/métodos , Neovascularización Coroidal/diagnóstico por imagen , Neovascularización Coroidal/tratamiento farmacológico , Retina/patología , Progresión de la EnfermedadRESUMEN
BACKGROUND AND OBJECTIVE: Retinal vessel segmentation plays an important role in the automatic retinal disease screening and diagnosis. How to segment thin vessels and maintain the connectivity of vessels are the key challenges of the retinal vessel segmentation task. Optical coherence tomography angiography (OCTA) is a noninvasive imaging technique that can reveal high-resolution retinal vessels. Aiming at make full use of its characteristic of high resolution, a new end-to-end transformer based network named as OCT2Former (OCT-a Transformer) is proposed to segment retinal vessel accurately in OCTA images. METHODS: The proposed OCT2Former is based on encoder-decoder structure, which mainly includes dynamic transformer encoder and lightweight decoder. Dynamic transformer encoder consists of dynamic token aggregation transformer and auxiliary convolution branch, in which the multi-head dynamic token aggregation attention based dynamic token aggregation transformer is designed to capture the global retinal vessel context information from the first layer throughout the network and the auxiliary convolution branch is proposed to compensate for the lack of inductive bias of the transformer and assist in the efficient feature extraction. A convolution based lightweight decoder is proposed to decode features efficiently and reduce the complexity of the proposed OCT2Former. RESULTS: The proposed OCT2Former is validated on three publicly available datasets i.e. OCTA-SS, ROSE-1, OCTA-500 (subset OCTA-6M and OCTA-3M). The Jaccard indexes of the proposed OCT2Former on these datasets are 0.8344, 0.7855, 0.8099 and 0.8513, respectively, outperforming the best convolution based network 1.43, 1.32, 0.75 and 1.46%, respectively. CONCLUSION: The experimental results have demonstrated that the proposed OCT2Former can achieve competitive performance on retinal OCTA vessel segmentation tasks.
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Tamizaje Masivo , Vasos Retinianos , Vasos Retinianos/diagnóstico por imagen , Angiografía con Fluoresceína/métodos , Tomografía de Coherencia Óptica/métodosRESUMEN
Retinal detachment (RD) and retinoschisis (RS) are the main complications leading to vision loss in high myopia. Accurate segmentation of RD and RS, including its subcategories (outer, middle, and inner retinoschisis) in optical coherence tomography images is of great clinical significance in the diagnosis and management of high myopia. For this multi-class segmentation task, we propose a novel framework named complementary multi-class segmentation networks. Based on domain knowledge, a three-class segmentation path (TSP) and a five-class segmentation path (FSP) are designed, and their outputs are integrated through additional decision fusion layers to achieve improved segmentation in a complementary manner. In TSP, a cross-fusion global feature module is adopted to achieve global receptive field. In FSP, a novel three-dimensional contextual information perception module is proposed to capture long-range contexts, and a classification branch is designed to provide useful features for segmentation. A new category loss is also proposed in FSP to help better identify the lesion categories. Experiment results show that the proposed method achieves superior performance for joint segmentation of RD and the three subcategories of RS, with an average Dice coefficient of 84.83%.
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Miopía , Desprendimiento de Retina , Retinosquisis , Humanos , Retinosquisis/diagnóstico por imagen , Retinosquisis/complicaciones , Desprendimiento de Retina/diagnóstico por imagen , Desprendimiento de Retina/complicaciones , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Miopía/complicaciones , Miopía/patología , Procesamiento de Imagen Asistido por ComputadorRESUMEN
BACKGROUND: Medical image segmentation is an important task in the diagnosis and treatment of cancers. The low contrast and highly flexible anatomical structure make it challenging to accurately segment the organs or lesions. PURPOSE: To improve the segmentation accuracy of the organs or lesions in magnetic resonance (MR) images, which can be useful in clinical diagnosis and treatment of cancers. METHODS: First, a selective feature interaction (SFI) module is designed to selectively extract the similar features of the sequence images based on the similarity interaction. Second, a multi-scale guided feature reconstruction (MGFR) module is designed to reconstruct low-level semantic features and focus on small targets and the edges of the pancreas. Third, to reduce manual annotation of large amounts of data, a semi-supervised training method is also proposed. Uncertainty estimation is used to further improve the segmentation accuracy. RESULTS: Three hundred ninety-five 3D MR images from 395 patients with pancreatic cancer, 259 3D MR images from 259 patients with brain tumors, and four-fold cross-validation strategy are used to evaluate the proposed method. Compared to state-of-the-art deep learning segmentation networks, the proposed method can achieve better segmentation of pancreas or tumors in MR images. CONCLUSIONS: SFI-Net can fuse dual sequence MR images for abnormal pancreas or tumor segmentation. The proposed semi-supervised strategy can further improve the performance of SFI-Net.
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Neoplasias Encefálicas , Neoplasias Pancreáticas , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias Pancreáticas/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodosRESUMEN
Skin wound segmentation in photographs allows non-invasive analysis of wounds that supports dermatological diagnosis and treatment. In this paper, we propose a novel feature augment network (FANet) to achieve automatic segmentation of skin wounds, and design an interactive feature augment network (IFANet) to provide interactive adjustment on the automatic segmentation results. The FANet contains the edge feature augment (EFA) module and the spatial relationship feature augment (SFA) module, which can make full use of the notable edge information and the spatial relationship information be-tween the wound and the skin. The IFANet, with FANet as the backbone, takes the user interactions and the initial result as inputs, and outputs the refined segmentation result. The pro-posed networks were tested on a dataset composed of miscellaneous skin wound images, and a public foot ulcer segmentation challenge dataset. The results indicate that the FANet gives good segmentation results while the IFANet can effectively improve them based on simple marking. Comprehensive comparative experiments show that our proposed networks outperform some other existing automatic or interactive segmentation methods, respectively.
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Polisorbatos , Piel , Humanos , Procesamiento de Imagen Asistido por Computador , Piel/diagnóstico por imagenRESUMEN
Choroidal neovascularization (CNV) is a typical symptom of age-related macular degeneration (AMD) and is one of the leading causes for blindness. Accurate segmentation of CNV and detection of retinal layers are critical for eye disease diagnosis and monitoring. In this paper, we propose a novel graph attention U-Net (GA-UNet) for retinal layer surface detection and CNV segmentation in optical coherence tomography (OCT) images. Due to retinal layer deformation caused by CNV, it is challenging for existing models to segment CNV and detect retinal layer surfaces with the correct topological order. We propose two novel modules to address the challenge. The first module is a graph attention encoder (GAE) in a U-Net model that automatically integrates topological and pathological knowledge of retinal layers into the U-Net structure to achieve effective feature embedding. The second module is a graph decorrelation module (GDM) that takes reconstructed features by the decoder of the U-Net as inputs, it then decorrelates and removes information unrelated to retinal layer for improved retinal layer surface detection. In addition, we propose a new loss function to maintain the correct topological order of retinal layers and the continuity of their boundaries. The proposed model learns graph attention maps automatically during training and performs retinal layer surface detection and CNV segmentation simultaneously with the attention maps during inference. We evaluated the proposed model on our private AMD dataset and another public dataset. Experiment results show that the proposed model outperformed the competing methods for retinal layer surface detection and CNV segmentation and achieved new state of the arts on the datasets.
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Neovascularización Coroidal , Degeneración Macular , Humanos , Tomografía de Coherencia Óptica/métodos , Retina/diagnóstico por imagen , Neovascularización Coroidal/diagnóstico por imagen , Neovascularización Coroidal/patología , Degeneración Macular/diagnóstico por imagen , Técnicas de Diagnóstico OftalmológicoRESUMEN
Keratoconus (KC) is a noninflammatory ectatic disease characterized by progressive thinning and an apical cone-shaped protrusion of the cornea. In recent years, more and more researchers have been committed to automatic and semi-automatic KC detection based on corneal topography. However, there are few studies about the severity grading of KC, which is particularly important for the treatment of KC. In this work, we propose a lightweight KC grading network (LKG-Net) for 4-level KC grading (Normal, Mild, Moderate, and Severe). First of all, we use depth-wise separable convolution to design a novel feature extraction block based on the self-attention mechanism, which can not only extract rich features but also reduce feature redundancy and greatly reduce the number of parameters. Then, to improve the model performance, a multi-level feature fusion module is proposed to fuse features from the upper and lower levels to obtain more abundant and effective features. The proposed LKG-Net was evaluated on the corneal topography of 488 eyes from 281 people with 4-fold cross-validation. Compared with other state-of-the-art classification methods, the proposed method achieves 89.55% for weighted recall (W_R), 89.98% for weighted precision (W_P), 89.50% for weighted F1 score (W_F1) and 94.38% for Kappa, respectively. In addition, the LKG-Net is also evaluated on KC screening, and the experimental results show the effectiveness.