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A Transfer Learning Approach Based on Ultrasound Images for Liver Cancer Detection
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作者 Murtada K.Elbashir Alshimaa Mahmoud +5 位作者 Ayman Mohamed Mostafa Eslam Hamouda Meshrif Alruily Sadeem M.Alotaibi Hosameldeen Shabana Mohamed Ezz 《Computers, Materials & Continua》 SCIE EI 2023年第6期5105-5121,共17页
The convolutional neural network(CNN)is one of the main algorithms that is applied to deep transfer learning for classifying two essential types of liver lesions;Hemangioma and hepatocellular carcinoma(HCC).Ultrasound... The convolutional neural network(CNN)is one of the main algorithms that is applied to deep transfer learning for classifying two essential types of liver lesions;Hemangioma and hepatocellular carcinoma(HCC).Ultrasound images,which are commonly available and have low cost and low risk compared to computerized tomography(CT)scan images,will be used as input for the model.A total of 350 ultrasound images belonging to 59 patients are used.The number of images with HCC is 202 and 148,respectively.These images were collected from ultrasound cases.info(28 Hemangiomas patients and 11 HCC patients),the department of radiology,the University of Washington(7 HCC patients),the Atlas of ultrasound Germany(3 HCC patients),and Radiopedia and others(10 HCC patients).The ultrasound images are divided into 225,52,and 73 for training,validation,and testing.A data augmentation technique is used to enhance the validation performance.We proposed an approach based on ensembles of the best-selected deep transfer models from the on-the-shelf models:VGG16,VGG19,DenseNet,Inception,InceptionResNet,ResNet,and EfficientNet.After tuning both the feature extraction and the classification layers,the best models are selected.Validation accuracy is used for model tuning and selection.The accuracy,sensitivity,specificity and AUROC are used to evaluate the performance.The experiments are concluded in five stages.The first stage aims to evaluate the base model performance by training the on-the-shelf models.The best accu-racy obtained in the first stage is 83.5%.In the second stage,we augmented the data and retrained the on-the-shelf models with the augmented data.The best accuracy we obtained in the second stage was 86.3%.In the third stage,we tuned the feature extraction layers of the on-the-shelf models.The best accuracy obtained in the third stage is 89%.In the fourth stage,we fine-tuned the classification layer and obtained an accuracy of 93%as the best accuracy.In the fifth stage,we applied the ensemble approach using the best three-performing models and obtained an accuracy,specificity,sensitivity,and AUROC of 94%,93.7%,95.1%,and 0.944,respectively. 展开更多
关键词 Transfer learning liver lesions ultrasound images and convolutional neural network
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Using shapes correlation for active contour segmentation of uterine fibroid ultrasound images in computer-aided therapy 被引量:14
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作者 NI Bo HE Fa-zhi +1 位作者 PAN Yi-teng YUAN Zhi-yong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第1期37-52,共16页
Segmenting the lesion regions from the ultrasound (US) images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound (HIFU), as a popular computer-... Segmenting the lesion regions from the ultrasound (US) images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound (HIFU), as a popular computer-aided therapy, has been widely used in the treatment of uterine fibroids. However, such segmentation in HIFU remains challenge for two reasons: (1) the blurry or missing boundaries of lesion regions in the HIFU images and (2) the deformation of uterine fibroids caused by the patient's breathing or an external force during the US imaging process, which can lead to complex shapes of lesion regions. These factors have prevented classical active contour-based segmentation methods from yielding desired results for uterine fibroids in US images. In this paper, a novel active contour-based segmentation method is proposed, which utilizes the correlation information of target shapes among a sequence of images as prior knowledge to aid the existing active contour method. This prior knowledge can be interpreted as a unsupervised clustering of shapes prior modeling. Meanwhile, it is also proved that the shapes correlation has the low-rank property in a linear space, and the theory of matrix recovery is used as an effective tool to impose the proposed prior on an existing active contour model. Finally, an accurate method is developed to solve the proposed model by using the Augmented Lagrange Multiplier (ALM). Experimental results from both synthetic and clinical uterine fibroids US image sequences demonstrate that the proposed method can consistently improve the performance of active contour models and increase the robustness against missing or misleading boundaries, and can greatly improve the efficiency of HIFU therapy. 展开更多
关键词 Active contour shapes correlation ultrasound image segmentation matrix recovery computer-aided therapy.
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3D Elastic Registration of Ultrasound Images Based on Skeleton Feature 被引量:1
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作者 LI Dan-dan LIU Zhi-Yan SHEN Yi 《Chinese Journal of Biomedical Engineering(English Edition)》 2005年第3期120-129,共10页
In order to eliminate displacement and elastic deformation between images of adjacent frames in course of 3D ultrasonic image reconstruction, elastic registration based on skeleton feature was adopt in this paper. A n... In order to eliminate displacement and elastic deformation between images of adjacent frames in course of 3D ultrasonic image reconstruction, elastic registration based on skeleton feature was adopt in this paper. A new automatically skeleton tracking extract algorithm is presented, which can extract connected skeleton to express figure feature. Feature points of connected skeleton are extracted automatically by accounting topical curvature extreme points several times. Initial registration is processed according to barycenter of skeleton. Whereafter, elastic registration based on radial basis function are processed according to feature points of skeleton. Result of example demonstrate that according to traditional rigid registration, elastic registration based on skeleton feature retain natural difference in shape for organr s different part, and eliminate slight elastic deformation between frames caused by image obtained process simultaneously. This algorithm has a high practical value for image registration in course of 3D ultrasound image reconstruction. 展开更多
关键词 Elastic registration Morphology skeleton ultrasound image
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A diffusion method based on polar coordinate for ultrasound images denoising
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作者 芦蓉 沈毅 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期568-572,共5页
The paper presents a novel anisotropic diffusion approach to the problem of ultrasound images denoising based on the polar-coordinate representation.Local gradients based on the polar coordinate are introduced and the... The paper presents a novel anisotropic diffusion approach to the problem of ultrasound images denoising based on the polar-coordinate representation.Local gradients based on the polar coordinate are introduced and they are more suitable for ultrasound images than horizontal gradients and vertical gradients commonly used in anisotropic diffusion methods.Moreover,an adaptive adjustment scheme for the threshold parameter in conduction functions is presented according to the incident angle of the ultrasonic beam with respect to the organ surface.Furthermore,based on the structure matrix,an edge-adaptive diffusion model is introduced,which can selectively preserve the edge from the blurring or smooth noise.Experimental results of real ultrasound images show the validity of the presented approach,which takes the physical imaging mechanism of ultrasonic devices into account. 展开更多
关键词 image denoising anisotropic diffusion polar coordinate ultrasound image
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Estimation of muscle pennation angle in ultrasound images using the beamlet transform
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作者 施俊 王锐玲 《Journal of Shanghai University(English Edition)》 2010年第1期34-38,共5页
Ultrasound imaging has been widely used to investigate the architecture properties of skeletal muscle, including the measurement of the pennation angle. In this study, we propose a beamlet-based algorithm to detect th... Ultrasound imaging has been widely used to investigate the architecture properties of skeletal muscle, including the measurement of the pennation angle. In this study, we propose a beamlet-based algorithm to detect the straight line- shaped patterns of aponeurosis, fascicle or bone, and then to quantify the pennation angle ix1 ultrasound images. The results demonstrate that the proposed algorithm can well detect the pennatoin angles in thirty ultrasound images with the correlation coefficient of 0.945, the standard root mean square error of 0.682°, and the relative root mean square error of 3.498%. The results suggest that this beamlet-based algorithm provides an alternative approach for the orientation estimation in muscu- loskeletal ultrasound images. 展开更多
关键词 skeletal muscle pennation angle ultrasound image beamlet transform
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A REVIEW ON ARTERY WALL SEGMENTATION TECHNIQUES AND INTIMA-MEDIA THICKNESS MEASUREMENT FOR CAROTID ULTRASOUND IMAGES
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作者 XIN YANG WANJI HE +4 位作者 KAITONG LI JIAOYING JIN XUMING ZHANG MING YUCHI MINGYUE DING 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2012年第1期75-84,共10页
Stroke and heart attack,which could be led by a kind of cerebrovascular and cardiovascular disease named as atherosclerosis,would seriously cause human morbidity and mortality.It is important for the early stage diagn... Stroke and heart attack,which could be led by a kind of cerebrovascular and cardiovascular disease named as atherosclerosis,would seriously cause human morbidity and mortality.It is important for the early stage diagnosis and monitoring medical intervention of the atherosclerosis.Carotid stenosis is a classical atherosclerotic lesion with vessel wall narrowing down and accumulating plaques burden.The carotid artery of intima-media thickness(IMT)is a key indicator to the disease.With the development of computer assisted diagnosis technology,the imaging techniques,segmentation algorithms,measurement methods,and evaluation tools have made considerable progress.Ultrasound imaging,being real-time,economic,reliable,and safe,now seems to become a standard in vascular assessment methodology especially for the measurement of IMT.This review firstly attempts to discuss the clinical relevance of measurements in clinical practice at first,and then followed by the challenges that one has to face when approaching the segmentation of ultrasound images.Secondly,the commonly used methods for the IMT segmentation and measurement are presented.Thirdly,discussion and evaluation of different segmentation techniques are performed.An overview of summary and future perspectives is given finally. 展开更多
关键词 ultrasound(US)images carotid artery intima-media thickness(IMT) ATHEROSCLEROSIS image segmentation computer assisted diagnosis(CAD)
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Automatic Fetal Segmentation Designed on Computer-Aided Detection with Ultrasound Images
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作者 Mohana Priya Govindarajan Sangeetha Subramaniam Karuppaiya Bharathi 《Computers, Materials & Continua》 SCIE EI 2024年第11期2967-2986,共20页
In the present research,we describe a computer-aided detection(CAD)method aimed at automatic fetal head circumference(HC)measurement in 2D ultrasonography pictures during all trimesters of pregnancy.The HC might be ut... In the present research,we describe a computer-aided detection(CAD)method aimed at automatic fetal head circumference(HC)measurement in 2D ultrasonography pictures during all trimesters of pregnancy.The HC might be utilized toward determining gestational age and tracking fetal development.This automated approach is particularly valuable in low-resource settings where access to trained sonographers is limited.The CAD system is divided into two steps:to begin,Haar-like characteristics were extracted from ultrasound pictures in order to train a classifier using random forests to find the fetal skull.We identified the HC using dynamic programming,an elliptical fit,and a Hough transform.The computer-aided detection(CAD)program was well-trained on 999 pictures(HC18 challenge data source),and then verified on 335 photos from all trimesters in an independent test set.A skilled sonographer and an expert in medicine personally marked the test set.We used the crown-rump length(CRL)measurement to calculate the reference gestational age(GA).In the first,second,and third trimesters,the median difference between the standard GA and the GA calculated by the skilled sonographer stayed at 0.7±2.7,0.0±4.5,and 2.0±12.0 days,respectively.The regular duration variance between the baseline GA and the health investigator’s GA remained 1.5±3.0,1.9±5.0,and 4.0±14 a couple of days.The mean variance between the standard GA and the CAD system’s GA remained between 0.5 and 5.0,with an additional variation of 2.9 to 12.5 days.The outcomes reveal that the computer-aided detection(CAD)program outperforms an expert sonographer.When paired with the classifications reported in the literature,the provided system achieves results that are comparable or even better.We have assessed and scheduled this computerized approach for HC evaluation,which includes information from all trimesters of gestation. 展开更多
关键词 Fetal growth segmentation ultrasound images computer-aided detection gestational age crown-rump length head circumference
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A Novel Approach to Breast Tumor Detection: Enhanced Speckle Reduction and Hybrid Classification in Ultrasound Imaging
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作者 K.Umapathi S.Shobana +5 位作者 Anand Nayyar Judith Justin R.Vanithamani Miguel Villagómez Galindo Mushtaq Ahmad Ansari Hitesh Panchal 《Computers, Materials & Continua》 SCIE EI 2024年第5期1875-1901,共27页
Breast cancer detection heavily relies on medical imaging, particularly ultrasound, for early diagnosis and effectivetreatment. This research addresses the challenges associated with computer-aided diagnosis (CAD) of ... Breast cancer detection heavily relies on medical imaging, particularly ultrasound, for early diagnosis and effectivetreatment. This research addresses the challenges associated with computer-aided diagnosis (CAD) of breastcancer fromultrasound images. The primary challenge is accurately distinguishing between malignant and benigntumors, complicated by factors such as speckle noise, variable image quality, and the need for precise segmentationand classification. The main objective of the research paper is to develop an advanced methodology for breastultrasound image classification, focusing on speckle noise reduction, precise segmentation, feature extraction, andmachine learning-based classification. A unique approach is introduced that combines Enhanced Speckle ReducedAnisotropic Diffusion (SRAD) filters for speckle noise reduction, U-NET-based segmentation, Genetic Algorithm(GA)-based feature selection, and Random Forest and Bagging Tree classifiers, resulting in a novel and efficientmodel. To test and validate the hybrid model, rigorous experimentations were performed and results state thatthe proposed hybrid model achieved accuracy rate of 99.9%, outperforming other existing techniques, and alsosignificantly reducing computational time. This enhanced accuracy, along with improved sensitivity and specificity,makes the proposed hybrid model a valuable addition to CAD systems in breast cancer diagnosis, ultimatelyenhancing diagnostic accuracy in clinical applications. 展开更多
关键词 ultrasound images breast cancer tumor classification SEGMENTATION deep learning lesion detection
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Ovarian-adnexal reporting and data system ultrasound evaluation and pathological characteristics of ovarian collision tumor
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作者 Chan Yin Yong Wang +3 位作者 Zhi-Hui Fei Li-Hong Sun Wei-Ai Zhou Heng Li 《World Journal of Clinical Cases》 SCIE 2024年第22期4932-4939,共8页
BACKGROUND Collision tumor are neoplasms,including two histologically distinct tumors that coexist in the same mass without histological admixture.The incidence of collision tumor is low and is rare clinically.AIM To ... BACKGROUND Collision tumor are neoplasms,including two histologically distinct tumors that coexist in the same mass without histological admixture.The incidence of collision tumor is low and is rare clinically.AIM To investigate ultrasound images and application of ovarian-adnexal reporting and data system(O-RADS)to evaluate the risk and pathological characteristics of ovarian collision tumor.METHODS This study retrospectively analyzed 17 cases of ovarian collision tumor diagnosed pathologically from January 2020 to December 2023.All clinical features,ultrasound images and histopathological features were collected and analyzed.The O-RADS score was used for classification.The O-RADS score was determined by two senior doctors in the gynecological ultrasound group.Lesions with O-RADS score of 1-3 were classified as benign tumors,and lesions with O-RADS score of 4 or 5 were classified as malignant tumors.RESULTS There were 17 collision tumors detected in 16 of 6274 patients who underwent gynecological surgery.The average age of 17 women with ovarian collision tumor was 36.7 years(range 20-68 years),in whom,one occurred bilaterally and the rest occurred unilaterally.The average tumor diameter was 10 cm,of which three were 2-5 cm,11 were 5-10 cm,and three were>10 cm.Five(29.4%)tumors with O-RADS score 3 were endometriotic cysts with fibroma/serous cystadenoma,and unilocular or multilocular cysts contained a small number of parenchymal components.Eleven(64.7%)tumors had an O-RADS score of 4,including two in category 4A,six in category 4B,and three in category 4C;all of which were multilocular cystic tumors with solid components or multiple papillary components.One(5.9%)tumor had an O-RADS score of 5.This case was a solid mass,and a small amount of pelvic effusion was detected under ultrasound.The pathology was high-grade serous cystic cancer combined with cystic mature teratoma.There were nine(52.9%)tumors with elevated serum carbohydrate antigen(CA)125 and two(11.8%)with elevated serum CA19-9.Histological and pathological results showed that epithelial-cell-derived tumors combined with other tumors were the most common,which was different from previous results.CONCLUSION The ultrasound images of ovarian collision tumor have certain specificity,but diagnosis by preoperative ultrasound is difficult.The combination of epithelial and mesenchymal cell tumors is one of the most common types of ovarian collision tumor.The O-RADS score of ovarian collision tumor is mostly≥4,which can sensitively detect malignant tumors. 展开更多
关键词 Ovarian collision tumor Ovarian-adnexal reporting and data system Epithelial tumor Serous cystadenoma ultrasound images
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Vault predicting after implantable collamer lens implantation using random forest network based on different features in ultrasound biomicroscopy images 被引量:2
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作者 Bin Fang Qiu-Jian Zhu +1 位作者 Hui Yang Li-Cheng Fan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第10期1561-1567,共7页
AIM:To analyze ultrasound biomicroscopy(UBM)images using random forest network to find new features to make predictions about vault after implantable collamer lens(ICL)implantation.METHODS:A total of 450 UBM images we... AIM:To analyze ultrasound biomicroscopy(UBM)images using random forest network to find new features to make predictions about vault after implantable collamer lens(ICL)implantation.METHODS:A total of 450 UBM images were collected from the Lixiang Eye Hospital to provide the patient’s preoperative parameters as well as the vault of the ICL after implantation.The vault was set as the prediction target,and the input elements were mainly ciliary sulcus shape parameters,which included 6 angular parameters,2 area parameters,and 2 parameters,distance between ciliary sulci,and anterior chamber height.A random forest regression model was applied to predict the vault,with the number of base estimators(n_estimators)of 2000,the maximum tree depth(max_depth)of 17,the number of tree features(max_features)of Auto,and the random state(random_state)of 40.0.RESULTS:Among the parameters selected in this study,the distance between ciliary sulci had a greater importance proportion,reaching 52%before parameter optimization is performed,and other features had less influence,with an importance proportion of about 5%.The importance of the distance between the ciliary sulci increased to 53% after parameter optimization,and the importance of angle 3 and area 1 increased to 5% and 8%respectively,while the importance of the other parameters remained unchanged,and the distance between the ciliary sulci was considered the most important feature.Other features,although they accounted for a relatively small proportion,also had an impact on the vault prediction.After parameter optimization,the best prediction results were obtained,with a predicted mean value of 763.688μm and an actual mean value of 776.9304μm.The R²was 0.4456 and the root mean square error was 201.5166.CONCLUSION:A study based on UBM images using random forest network can be performed for prediction of the vault after ICL implantation and can provide some reference for ICL size selection. 展开更多
关键词 random forest network ultrasound biomicroscopy images vault prediction implantable collamer lens
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Computer-aided recognition and assessment of a porous bioelastomer in ultrasound images for regenerative medicine applications
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作者 Dun Wang Sheng Yang +5 位作者 Kai-Xuan Guo Yan-Ying Zhu Jia Sun Aliona Dreglea Yan-Hong Gao Jiao Yu 《Medicine in Novel Technology and Devices》 2023年第3期41-52,共12页
It is difficult to use a single edge operator in image processing to extract continuous and accurate contours of a porous bioelastomer due to the fuzzy boundary and complex background in ultrasound images.To solve thi... It is difficult to use a single edge operator in image processing to extract continuous and accurate contours of a porous bioelastomer due to the fuzzy boundary and complex background in ultrasound images.To solve this problem,this paper proposes a joint algorithm for bioelastomer contour detection and a texture feature extraction method for monitoring the degradation performance of bioelastomers.First,the mean-shift clustering method is utilized to obtain the clustering feature information of bioelastomers and native tissue from manually segmented images,and this information is used as the initial information in the image binarization algorithm for image partitioning.Second,Otsu's thresholding method and mathematical morphology are applied in the process of image binarization.Finally,the Canny edge detector is employed to extract the complete bioelastomers contour from the binary image.To verify the robustness of the proposed joint algorithm,the results using the proposed joint algorithm,where mean-shift clustering is replaced with k-means clustering are also obtained.The proposed joint algorithm based on mean-shift clustering outperforms the joint algorithm based on k-means clustering,as well as algorithms that directly apply the Canny,Sobel and Laplacian methods.Texture feature extraction is based on the computer-aided recognition of bioelastomers.The region of interest(ROI)is set in the scaffold region,and the first-order statistical features and second-order statistical features of the greyscale values of the ROI are extracted and analysed.The proposed joint algorithm can not only extract ideal bioelastomers contours from ultrasound images but also provide valuable feedback on the degradation behaviour of bioelastomers at implant sites. 展开更多
关键词 ultrasound imaging Computer-aided recognition Tissue repair Bioelastomers
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A Modified CycleGAN for Multi-Organ Ultrasound Image Enhancement via Unpaired Pre-Training
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作者 Haonan Han Bingyu Yang +2 位作者 Weihang Zhang Dongwei Li Huiqi Li 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期194-203,共10页
Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early screening.However,the image qual... Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early screening.However,the image quality of handheld ultrasound devices is not always satisfactory due to the limited equipment size,which hinders accurate diagnoses by doctors.At the same time,paired ultrasound images are difficult to obtain from the clinic because imaging process is complicated.Therefore,we propose a modified cycle generative adversarial network(cycleGAN) for ultrasound image enhancement from multiple organs via unpaired pre-training.We introduce an ultrasound image pre-training method that does not require paired images,alleviating the requirement for large-scale paired datasets.We also propose an enhanced block with different structures in the pre-training and fine-tuning phases,which can help achieve the goals of different training phases.To improve the robustness of the model,we add Gaussian noise to the training images as data augmentation.Our approach is effective in obtaining the best quantitative evaluation results using a small number of parameters and less training costs to improve the quality of handheld ultrasound devices. 展开更多
关键词 ultrasound image enhancement handheld devices unpaired images pre-train and finetune cycleGAN
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The Application Value of Ultrasound Imaging in the Differential Diagnosis of Benign and Malignant Breast Nodules of BI-RADS 3 and Above
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作者 Dongmei Chen 《Proceedings of Anticancer Research》 2024年第2期53-58,共6页
Objective:To explore the diagnostic value of ultrasound imaging for breast nodules of breast imaging-reporting and data system(BI-RADS)category 3 and above.Methods:From June 2021 to July 2022,163 patients with breast ... Objective:To explore the diagnostic value of ultrasound imaging for breast nodules of breast imaging-reporting and data system(BI-RADS)category 3 and above.Methods:From June 2021 to July 2022,163 patients with breast nodules of BI-RADS 3 or above were selected as the research subjects.After pathological diagnosis,24 cases were malignant breast nodules of BI-RADS 3 or above,while 139 cases were benign breast nodules of BI-RADS 3 or above.The diagnosis rate of malignant and benign breast nodules of BI-RADS 3 or above,including 95%CI,was observed and analyzed.Results:The malignant and benign detection rates of conventional ultrasound were 88.63%and 75.00%,respectively,and the malignant and benign detection rates of ultrasound imaging were 93.18%and 87.50%,respectively,with 95%CIs greater than 0.7.Conclusion:Ultrasound imaging can help improve the diagnostic accuracy of benign and malignant breast nodules of BI-RADS 3 and above and reduce the misdiagnosis rate. 展开更多
关键词 ultrasound ultrasound imaging Breast imaging-reporting and data system(BI-RADS)category 3 and above Diagnosis
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THREE-DIMENSIONAL RECONSTRUCTION OF TWODIMENSIONAL INTRAVASCULAR ULTRASOUND IMAGES
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作者 Lothar Koch Thomas Roth +2 位作者 Gunter Gorge Michael Haude Raimund Erbel 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第3期71-71,共1页
The purpose of the study is to reconstruct the coronary arteries in 3 dimension (3D) from serial intravascular ultrasound (IVUS) images generated during a pullback of IVUS catheter. Slowly pullback. real-time, cross-s... The purpose of the study is to reconstruct the coronary arteries in 3 dimension (3D) from serial intravascular ultrasound (IVUS) images generated during a pullback of IVUS catheter. Slowly pullback. real-time, cross-sectional IVUS images of 18 patients (2 with normal coronary arteries. 1 with coronary aneurysm. and 15 post PTCA) were obtained by using a 20 MHz. 3.5F IVUS catheter and recorded on video tape. A series of 90-frame consecutive IVUS images were digitized into a SUN Spare 11 workstation. Digitized data were reconstructed to 3D images with use of voxel space modeling and were generated in both sagittal and cylindrical formats. The sagittal format results in a longitudinal 展开更多
关键词 IVUS THREE-DIMENSIONAL RECONSTRUCTION OF TWODIMENSIONAL INTRAVASCULAR ultrasound images PTCA
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A Patch-Based Low-Rank Minimization Approach for Speckle Noise Reduction in Ultrasound Images
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作者 Xiao-Guang Lv Fang Li +1 位作者 Jun Liu Sheng-Tai Lu 《Advances in Applied Mathematics and Mechanics》 SCIE 2022年第1期155-180,共26页
Ultrasound is a low-cost,non-invasive and real-time imaging modality that has proved popular for many medical applications.Unfortunately,the acquired ultrasound images are often corrupted by speckle noise from scatter... Ultrasound is a low-cost,non-invasive and real-time imaging modality that has proved popular for many medical applications.Unfortunately,the acquired ultrasound images are often corrupted by speckle noise from scatterers smaller than ultrasound beam wavelength.The signal-dependent speckle noise makes visual observation difficult.In this paper,we propose a patch-based low-rank approach for reducing the speckle noise in ultrasound images.After constructing the patch group of the ultrasound images by the block-matching scheme,we establish a variational model using the weighted nuclear norm as a regularizer for the patch group.The alternating direction method of multipliers(ADMM)is applied for solving the established nonconvex model.We return all the approximate patches to their original locations and get the final restored ultrasound images.Experimental results are given to demonstrate that the proposed method outperforms some existing state-of-the-art methods in terms of visual quality and quantitative measures. 展开更多
关键词 ultrasound images PATCH speckle noise low-rank weighted nuclear norm minimization
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A fast automatic recognition and location algorithm for fetal genital organs in ultrasound images
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作者 Sheng TANG Si-ping CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2009年第9期648-658,共11页
Severe sex ratio imbalance at birth is now becoming an important issue in several Asian countries. Its leading immediate cause is prenatal sex-selective abortion following illegal sex identification by ultrasound scan... Severe sex ratio imbalance at birth is now becoming an important issue in several Asian countries. Its leading immediate cause is prenatal sex-selective abortion following illegal sex identification by ultrasound scanning. In this paper, a fast automatic recognition and location algorithm for fetal genital organs is proposed as an effective method to help prevent ultrasound technicians from unethically and illegally identifying the sex of the fetus. This automatic recognition algorithm can be divided into two stages. In the 'rough' stage, a few pixels in the image, which are likely to represent the genital organs, are automatically chosen as points of interest (POIs) according to certain salient characteristics of fetal genital organs. In the 'fine' stage, a specifically supervised learning framework, which fuses an effective feature data preprocessing mechanism into the multiple classifier architecture, is applied to every POI. The basic classifiers in the framework are selected from three widely used classifiers: radial basis function network, backpropagation network, and support vector machine. The classification results of all the POIs are then synthesized to determine whether the fetal genital organ is present in the image, and to locate the genital organ within the positive image. Experiments were designed and carried out based on an image dataset comprising 658 positive images (images with fetal genital organs) and 500 negative images (images without fetal genital organs). The experimental results showed true positive (TP) and true negative (TN) results from 80.5% (265 from 329) and 83.0% (415 from 500) of samples, respectively. The average computation time was 453 ms per image. 展开更多
关键词 ultrasound image Fetal genital organ Point of interest (POI) Feature selection Feature extraction Class imbalance Multiple classifier architecture
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Application and prospects of AI-based radiomics in ultrasound diagnosis
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作者 Haoyan Zhang Zheling Meng +2 位作者 Jinyu Ru Yaqing Meng Kun Wang 《Visual Computing for Industry,Biomedicine,and Art》 EI 2023年第1期288-303,共16页
Artificial intelligence (AI)-based radiomics has attracted considerable research attention in the field of medical imaging, including ultrasound diagnosis. Ultrasound imaging has unique advantages such as high tempora... Artificial intelligence (AI)-based radiomics has attracted considerable research attention in the field of medical imaging, including ultrasound diagnosis. Ultrasound imaging has unique advantages such as high temporal resolution, low cost, and no radiation exposure. This renders it a preferred imaging modality for several clinical scenarios. This review includes a detailed introduction to imaging modalities, including Brightness-mode ultrasound, color Doppler flow imaging, ultrasound elastography, contrast-enhanced ultrasound, and multi-modal fusion analysis. It provides an overview of the current status and prospects of AI-based radiomics in ultrasound diagnosis, highlighting the application of AI-based radiomics to static ultrasound images, dynamic ultrasound videos, and multi-modal ultrasound fusion analysis. 展开更多
关键词 Radiomics ultrasound imaging Artificial intelligence Deep learning B-mode ultrasound Color Doppler flow imaging ultrasound elastography Contrast-enhanced ultrasound Multimodal ultrasound
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Quantitative ultrasound brain imaging with multiscale deconvolutional waveform inversion
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作者 李玉冰 王建 +3 位作者 苏畅 林伟军 王秀明 骆毅 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期362-372,共11页
High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner.Sound speed mapping of brain tissues provides unique information for such a purpose.In additi... High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner.Sound speed mapping of brain tissues provides unique information for such a purpose.In addition,it is particularly important for building digital human acoustic models,which form a reference for future ultrasound research.Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue.We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique,originating from the geophysics community,is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals.The successful implementation of such an approach to brain imaging requires the following items:signals of sub-megahertz frequencies transmitting across the inside of skull,an accurate numerical wave equation solver simulating the wave propagation,and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory.Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution,by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter.We implement the proposed approach to iteratively update the parametric models of the human brain.The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases,in a potentially more portable,more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography. 展开更多
关键词 ultrasound brain imaging full waveform inversion high resolution digital body
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Image-Based Ultrasound Speed Estimation: Phantom and Human Liver Studies
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作者 Jianfeng Chen Junguo Bian +2 位作者 Zuhaib Khokhar Mohamed Belal Emad Allam 《Open Journal of Radiology》 2023年第2期101-112,共12页
Purpose: A novel image-based method for speed of sound (SoS) estimation is proposed and experimentally validated on a tissue-mimicking ultrasound phantom and normal human liver in vivo using linear and curved array tr... Purpose: A novel image-based method for speed of sound (SoS) estimation is proposed and experimentally validated on a tissue-mimicking ultrasound phantom and normal human liver in vivo using linear and curved array transducers. Methods: When the beamforming SoS settings are adjusted to match the real tissue’s SoS, the ultrasound image at regions of interest will be in focus and the image quality will be optimal. Based on this principle, both a tissue-mimicking ultrasound phantom and normal human liver in vivo were used in this study. Ultrasound image was acquired using different SoS settings in beamforming channels ranging from 1420 m/sec to 1600 m/sec. Two regions of interest (ROIs) were selected. One was in a fully developed speckle region, while the other contained specular reflectors. We evaluated the image quality of these two ROIs in images acquired at different SoS settings in beamforming channels by using the normalized autocorrelation function (ACF) of the image data. The values of the normalized ACF at a specific lag as a function of the SoS setting were computed. Subsequently, the soft tissue’s SoS was determined from the SoS setting at the minimum value of the normalized ACF. Results: The value of the ACF as a function of the SoS setting can be computed for phantom and human liver images. SoS in soft tissue can be determined from the SoS setting at the minimum value of the normalized ACF. The estimation results show that the SoS of the tissue-mimicking phantom is 1460 m/sec, which is consistent with the phantom manufacturer’s specification, and the SoS of the normal human liver is 1540 m/sec, which is within the range of the SoS in a healthy human liver in vivo. Conclusion: Soft tissue’s SoS can be determined by analyzing the normalized ACF of ultrasound images. The method is based on searching for a minimum of the normalized ACF of ultrasound image data with a specific lag among different SoS settings in beamforming channels. 展开更多
关键词 ultrasound Image Normalized Autocorrelation Function (ACF) Speed of Sound (SoS)
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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