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1.
Opt Express ; 32(6): 9867-9876, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571211

RESUMO

Orbit-induced localized spin angular momentum (OILS) has recently garnered significant attention. This paper introduces periodic edge dislocation (PED) into the tight focusing system. The study delves into the tight focusing characteristics of the radially polarized vortex plane beam with PED, demonstrating that PED serves as a straightforward and effective means of manipulating OILS, especially when both the orbital angular momentum and the polarization of the incident beam are fixed. Our findings indicate that the longitudinal OILS reaches its maximum when the difference between the period of PED and the vortex topological charge is equal to 1. Conversely, when the difference is 0, the transverse OILS reaches its maximum, while the longitudinal OILS reaches its minimum. Similar patterns are also observed in linearly polarized vortex beams. This research proposes a simple and practical way to control OILS, contributing to our understanding of optical orbit-spin coupling.

2.
Comput Biol Med ; 154: 106608, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36731364

RESUMO

Vessel segmentation in fundus images is a key procedure in the diagnosis of ophthalmic diseases, which can play a role in assisting doctors in diagnosis. Although current deep learning-based methods can achieve high accuracy in segmenting fundus vessel images, the results are not satisfactory in segmenting microscopic vessels that are close to the background region. The reason for this problem is that thin blood vessels contain very little information, with the convolution operation of each layer in the deep network, this part of the information will be randomly lost. To improve the segmentation ability of the small blood vessel region, a multi-input network (MINet) was proposed to segment vascular regions more accurately. We designed a multi-input fusion module (MIF) in the encoder, which is proposed to acquire multi-scale features in the encoder stage while preserving the microvessel feature information. In addition, to further aggregate multi-scale information from adjacent regions, a multi-scale atrous spatial pyramid (MASP) module is proposed. This module can enhance the extraction of vascular information without reducing the resolution loss. In order to better recover segmentation results with details, we designed a refinement module, which acts on the last layer of the network output to refine the results of the last layer of the network to get more accurate segmentation results. We use the HRF, CHASE_DB1 public dataset to validate the fundus vessel segmentation performance of the MINet model. Also, we merged these two public datasets with our collected Ultra-widefield fundus image (UWF) data as one dataset to test the generalization ability of the model. Experimental results show that MINet achieves an F1 score of 0.8324 on the microvessel segmentation task, achieving a high accuracy compared to the current mainstream models.


Assuntos
Algoritmos , Vasos Retinianos , Vasos Retinianos/diagnóstico por imagem , Fundo de Olho , Processamento de Imagem Assistida por Computador/métodos
3.
Diagnostics (Basel) ; 12(12)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36553140

RESUMO

In computer-aided diagnosis methods for breast cancer, deep learning has been shown to be an effective method to distinguish whether lesions are present in tissues. However, traditional methods only classify masses as benign or malignant, according to their presence or absence, without considering the contextual features between them and their adjacent tissues. Furthermore, for contrast-enhanced spectral mammography, the existing studies have only performed feature extraction on a single image per breast. In this paper, we propose a multi-input deep learning network for automatic breast cancer classification. Specifically, we simultaneously input four images of each breast with different feature information into the network. Then, we processed the feature maps in both horizontal and vertical directions, preserving the pixel-level contextual information within the neighborhood of the tumor during the pooling operation. Furthermore, we designed a novel loss function according to the information bottleneck theory to optimize our multi-input network and ensure that the common information in the multiple input images could be fully utilized. Our experiments on 488 images (256 benign and 232 malignant images) from 122 patients show that the method's accuracy, precision, sensitivity, specificity, and f1-score values are 0.8806, 0.8803, 0.8810, 0.8801, and 0.8806, respectively. The qualitative, quantitative, and ablation experiment results show that our method significantly improves the accuracy of breast cancer classification and reduces the false positive rate of diagnosis. It can reduce misdiagnosis rates and unnecessary biopsies, helping doctors determine accurate clinical diagnoses of breast cancer from multiple CESM images.

4.
Med Phys ; 49(2): 966-977, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34860417

RESUMO

PURPOSE: Contrast-enhanced spectral mammography (CESM) is an effective tool for diagnosing breast cancer with the benefit of its multiple types of images. However, few models simultaneously utilize this feature in deep learning-based breast cancer classification methods. To combine multiple features of CESM and thus aid physicians in making accurate diagnoses, we propose a hybrid approach by taking advantages of both fusion and classification models. METHODS: We evaluated the proposed method on a CESM dataset obtained from 95 patients between ages ranging from 21 to 74 years, with a total of 760 images. The framework consists of two main parts: a generative adversarial network based image fusion module and a Res2Net-based classification module. The aim of the fusion module is to generate a fused image that combines the characteristics of dual-energy subtracted (DES) and low-energy (LE) images, and the classification module is developed to classify the fused image into benign or malignant. RESULTS: Based on the experimental results, the fused images contained complementary information of the images of both types (DES and LE), whereas the model for classification achieved accurate classification results. In terms of qualitative indicators, the entropy of the fused images was 2.63, and the classification model achieved an accuracy of 94.784%, precision of 95.016%, recall of 95.912%, specificity of 0.945, F1_score of 0.955, and area under curve of 0.947 on the test dataset, respectively. CONCLUSIONS: We conducted extensive comparative experiments and analyses on our in-house dataset, and demonstrated that our method produces promising results in the fusion of CESM images and is more accurate than the state-of-the-art methods in classification of fused CESM.


Assuntos
Neoplasias da Mama , Meios de Contraste , Adulto , Idoso , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Adulto Jovem
5.
Opt Express ; 29(14): 22732-22748, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34266030

RESUMO

Multicolor (MC) imaging is an imaging modality that records confocal scanning laser ophthalmoscope (cSLO) fundus images, which can be used for the diabetic retinopathy (DR) detection. By utilizing this imaging technique, multiple modal images can be obtained in a single case. Additional symptomatic features can be obtained if these images are considered during the diagnosis of DR. However, few studies have been carried out to classify MC Images using deep learning methods, let alone using multi modal features for analysis. In this work, we propose a novel model which uses the multimodal information bottleneck network (MMIB-Net) to classify the MC Images for the detection of DR. Our model can extract the features of multiple modalities simultaneously while finding concise feature representations of each modality using the information bottleneck theory. MC Images classification can be achieved by picking up the combined representations and features of all modalities. In our experiments, it is shown that the proposed method can achieve an accurate classification of MC Images. Comparative experiments also demonstrate that the use of multimodality and information bottleneck improves the performance of MC Images classification. To the best of our knowledge, this is the first report of DR identification utilizing the multimodal information bottleneck convolutional neural network in MC Images.


Assuntos
Aprendizado Profundo , Retinopatia Diabética/diagnóstico , Diagnóstico por Imagem/classificação , Retina/diagnóstico por imagem , Fundo de Olho , Humanos , Estudos Retrospectivos
6.
Int J Comput Assist Radiol Surg ; 16(6): 979-988, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33966155

RESUMO

PURPOSE: CESM (contrast-enhanced spectral mammography) is an efficient tool for detecting breast cancer because of its image characteristics. However, among most deep learning-based methods for breast cancer classification, few models can integrate both its multiview and multimodal features. To effectively utilize the image features of CESM and thus help physicians to improve the accuracy of diagnosis, we propose a multiview multimodal network (MVMM-Net). METHODS: The experiment is carried out to evaluate the in-house CESM images dataset taken from 95 patients aged 21-74 years with 760 images. The framework consists of three main stages: the input of the model, image feature extraction, and image classification. The first stage is to preprocess the CESM to utilize its multiview and multimodal features effectively. In the feature extraction stage, a deep learning-based network is used to extract CESM images features. The last stage is to integrate different features for classification using the MVMM-Net model. RESULTS: According to the experimental results, the proposed method based on the Res2Net50 framework achieves an accuracy of 96.591%, sensitivity of 96.396%, specificity of 96.350%, precision of 96.833%, F1_score of 0.966, and AUC of 0.966 on the test set. Comparative experiments illustrate that the classification performance of the model can be improved by using multiview multimodal features. CONCLUSION: We proposed a deep learning classification model that combines multiple features of CESM. The results of the experiment indicate that our method is more precise than the state-of-the-art methods and produces accurate results for the classification of CESM images.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Meios de Contraste/farmacologia , Mamografia/métodos , Imagem Multimodal/métodos , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
7.
Nutrients ; 12(10)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053638

RESUMO

This study aimed to examine the impact of a wide range of demographic, socioeconomic, and community factors on the double burden of malnutrition among women of reproductive age using longitudinal data. We used data about 11,348 women of reproductive age who participated in the China Health and Nutrition Survey (CHNS), a longitudinal survey, between 1989 and 2015. Nutritional outcomes were categorized into four groups, namely underweight, normal weight, overweight, and obesity, with normal weight as reference. A multinomial logit model was fitted due to geographic clustering and repeated observations of individuals. The prevalence of underweight decreased over time from 1991 but has tended to rise again since 2004, while the prevalence of overweight/obesity continued to rise between 1991 and 2015. Improved individual factors, socioeconomic status, and community urbanization reduced the risk of underweight but elevated the risk of overweight and obesity. The medium levels, rather than the highest levels, of household income and community urbanization are associated with a higher risk of overweight and obesity. The notable increase in underweight prevalence is a cause for concern to be addressed along with efforts to curb the rising tide of overweight. In order to enhance the nutritional status of women of reproductive age, it is essential to improving the community environment, levels of education, and living environment from a wider context. Long-term and targeted plans are urgently needed for nutrition improvements among the different populations.


Assuntos
Povo Asiático , Desnutrição/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Determinantes Sociais da Saúde , Fatores Socioeconômicos , Magreza/epidemiologia , Adolescente , Adulto , China , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Estudos Longitudinais , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estado Nutricional , Prevalência , População Rural , População Urbana , Adulto Jovem
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