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1.
Sci Rep ; 14(1): 4782, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413748

RESUMO

Any kidney dimension and volume variation can be a remarkable indicator of kidney disorders. Precise kidney segmentation in standard planes plays an undeniable role in predicting kidney size and volume. On the other hand, ultrasound is the modality of choice in diagnostic procedures. This paper proposes a convolutional neural network with nested layers, namely Fast-Unet++, promoting the Fast and accurate Unet model. First, the model was trained and evaluated for segmenting sagittal and axial images of the kidney. Then, the predicted masks were used to estimate the kidney image biomarkers, including its volume and dimensions (length, width, thickness, and parenchymal thickness). Finally, the proposed model was tested on a publicly available dataset with various shapes and compared with the related networks. Moreover, the network was evaluated using a set of patients who had undergone ultrasound and computed tomography. The dice metric, Jaccard coefficient, and mean absolute distance were used to evaluate the segmentation step. 0.97, 0.94, and 3.23 mm for the sagittal frame, and 0.95, 0.9, and 3.87 mm for the axial frame were achieved. The kidney dimensions and volume were evaluated using accuracy, the area under the curve, sensitivity, specificity, precision, and F1.


Assuntos
Redes Neurais de Computação , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia , Rim/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
2.
Phys Med ; 107: 102560, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36878133

RESUMO

PURPOSE: Breast cancer is one of the major reasons of death due to cancer in women. Early diagnosis is the most critical key for disease screening, control, and reducing mortality. A robust diagnosis relies on the correct classification of breast lesions. While breast biopsy is referred to as the "gold standard" in assessing both the activity and degree of breast cancer, it is an invasive and time-consuming approach. METHOD: The current study's primary objective was to develop a novel deep-learning architecture based on the InceptionV3 network to classify ultrasound breast lesions. The main promotions of the proposed architecture were converting the InceptionV3 modules to residual inception ones, increasing their number, and altering the hyperparameters. In addition, we used a combination of five datasets (three public datasets and two prepared from different imaging centers) for training and evaluating the model. RESULTS: The dataset was split into the train (80%) and test (20%) groups. The model achieved 0.83, 0.77, 0.8, 0.81, 0.81, 0.18, and 0.77 for the precision, recall, F1 score, accuracy, AUC, Root Mean Squared Error, and Cronbach's α in the test group, respectively. CONCLUSIONS: This study illustrates that the improved InceptionV3 can robustly classify breast tumors, potentially reducing the need for biopsy in many cases.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Feminino , Humanos , Redes Neurais de Computação , Aprendizado de Máquina , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia
3.
Insights Imaging ; 13(1): 69, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35394221

RESUMO

BACKGROUND: Accurate cardiac volume and function assessment have valuable and significant diagnostic implications for patients suffering from ventricular dysfunction and cardiovascular disease. This study has focused on finding a reliable assistant to help physicians have more reliable and accurate cardiac measurements using a deep neural network. EchoRCNN is a semi-automated neural network for echocardiography sequence segmentation using a combination of mask region-based convolutional neural network image segmentation structure with reference-guided mask propagation video object segmentation network. RESULTS: The proposed method accurately segments the left and right ventricle regions in four-chamber view echocardiography series with a dice similarity coefficient of 94.03% and 94.97%, respectively. Further post-processing procedures on the segmented left and right ventricle regions resulted in a mean absolute error of 3.13% and 2.03% for ejection fraction and fractional area change parameters, respectively. CONCLUSION: This study has achieved excellent performance on the left and right ventricle segmentation, leading to more accurate estimations of vital cardiac parameters such as ejection fraction and fractional area change parameters in the left and right ventricle functionalities, respectively. The results represent that our method can predict an assured, accurate, and reliable cardiac function diagnosis in clinical screenings.

4.
Sci Rep ; 12(1): 6717, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468984

RESUMO

We introduced Double Attention Res-U-Net architecture to address medical image segmentation problem in different medical imaging system. Accurate medical image segmentation suffers from some challenges including, difficulty of different interest object modeling, presence of noise, and signal dropout throughout the measurement. The base line image segmentation approaches are not sufficient for complex target segmentation throughout the various medical image types. To overcome the issues, a novel U-Net-based model proposed that consists of two consecutive networks with five and four encoding and decoding levels respectively. In each of networks, there are four residual blocks between the encoder-decoder path and skip connections that help the networks to tackle the vanishing gradient problem, followed by the multi-scale attention gates to generate richer contextual information. To evaluate our architecture, we investigated three distinct data-sets, (i.e., CVC-ClinicDB dataset, Multi-site MRI dataset, and a collected ultrasound dataset). The proposed algorithm achieved Dice and Jaccard coefficients of 95.79%, 91.62%, respectively for CRL, and 93.84% and 89.08% for fetal foot segmentation. Moreover, the proposed model outperformed the state-of-the-art U-Net based model on the external CVC-ClinicDB, and multi-site MRI datasets with Dice and Jaccard coefficients of 83%, 75.31% for CVC-ClinicDB, and 92.07% and 87.14% for multi-site MRI dataset, respectively.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Algoritmos , Atenção , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos
5.
Ultrason Imaging ; 44(1): 25-38, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34986724

RESUMO

U-Net based algorithms, due to their complex computations, include limitations when they are used in clinical devices. In this paper, we addressed this problem through a novel U-Net based architecture that called fast and accurate U-Net for medical image segmentation task. The proposed fast and accurate U-Net model contains four tuned 2D-convolutional, 2D-transposed convolutional, and batch normalization layers as its main layers. There are four blocks in the encoder-decoder path. The results of our proposed architecture were evaluated using a prepared dataset for head circumference and abdominal circumference segmentation tasks, and a public dataset (HC18-Grand challenge dataset) for fetal head circumference measurement. The proposed fast network significantly improved the processing time in comparison with U-Net, dilated U-Net, R2U-Net, attention U-Net, and MFP U-Net. It took 0.47 seconds for segmenting a fetal abdominal image. In addition, over the prepared dataset using the proposed accurate model, Dice and Jaccard coefficients were 97.62% and 95.43% for fetal head segmentation, 95.07%, and 91.99% for fetal abdominal segmentation. Moreover, we have obtained the Dice and Jaccard coefficients of 97.45% and 95.00% using the public HC18-Grand challenge dataset. Based on the obtained results, we have concluded that a fine-tuned and a simple well-structured model used in clinical devices can outperform complex models.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Algoritmos , Processamento de Imagem Assistida por Computador/métodos
6.
Phys Med ; 88: 127-137, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34242884

RESUMO

PURPOSE: Fetal biometric measurements face a number of challenges, including the presence of speckle, limited soft-tissue contrast and difficulties in the presence of low amniotic fluid. This work proposes a convolutional neural network for automatic segmentation and measurement of fetal biometric parameters, including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) from ultrasound images that relies on the attention gates incorporated into the multi-feature pyramid Unet (MFP-Unet) network. METHODS: The proposed approach, referred to as Attention MFP-Unet, learns to extract/detect salient regions automatically to be treated as the object of interest via the attention gates. After determining the type of anatomical structure in the image using a convolutional neural network, Niblack's thresholding technique was applied as pre-processing algorithm for head and abdomen identification, whereas a novel algorithm was used for femur extraction. A publicly-available dataset (HC18 grand-challenge) and clinical data of 1334 subjects were utilized for training and evaluation of the Attention MFP-Unet algorithm. RESULTS: Dice similarity coefficient (DSC), hausdorff distance (HD), percentage of good contours, the conformity coefficient, and average perpendicular distance (APD) were employed for quantitative evaluation of fetal anatomy segmentation. In addition, correlation analysis, good contours, and conformity were employed to evaluate the accuracy of the biometry predictions. Attention MFP-Unet achieved 0.98, 1.14 mm, 100%, 0.95, and 0.2 mm for DSC, HD, good contours, conformity, and APD, respectively. CONCLUSIONS: Quantitative evaluation demonstrated the superior performance of the Attention MFP-Unet compared to state-of-the-art approaches commonly employed for automatic measurement of fetal biometric parameters.


Assuntos
Biometria , Redes Neurais de Computação , Algoritmos , Cabeça/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Ultrassonografia
7.
Int J Artif Organs ; 32(10): 739-44, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19943235

RESUMO

PURPOSE: Despite increasing transplantation in Iran, organ shortage and long waiting lists remain major problems in the country. Many publications have demonstrated that the willingness of healthcare professionals to participate in the donation process can improve the donation rate. Since nurses are usually the first people among the healthcare staff to recognize a patient as a potential donor, they have an important role in the procurement of organ and tissue from cadaveric donors. Our objectives were to survey nurses' knowledge and attitudes toward organ and tissue donation and to examine the effect of having them attend a workshop on organ donation. METHODS: A 39-item questionnaire was completed by 66 nurses, before and after participation in a 1-day organ donation workshop that was held at the Iranian Tissue Bank (in Tehran, Iran). The questionnaire contained demographic data, 29 questions regarding knowledge, and 8 questions on attitudes toward organ and tissue donation. RESULTS: 69.7% women and 30.3% men participated in this study. The mean score for knowledge was 16.89 (SD= 3.33) before and 23.76 (SD=1.66) after the workshop (p=0.000). The mean attitudes score was 4.76 (SD=1.71) before and 5.08 (SD=1.34) after the workshop (p=0.235). Although 63.63% claimed they were willing to have a donation card only 15.15% actually carried one. CONCLUSIONS: This study demonstrated that educational programs can enhance nurses' knowledge and commitment to the organ donation process and, ultimately, increase the donation rate. Consequently, it is of great importance for organ procurement units to focus on regular training programs for all their healthcare staff.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Papel do Profissional de Enfermagem/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Doadores de Tecidos/psicologia , Obtenção de Tecidos e Órgãos , Adulto , Características Culturais , Currículo , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Irã (Geográfico) , Masculino , Recursos Humanos de Enfermagem Hospitalar/educação , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários , Doadores de Tecidos/provisão & distribuição , Recursos Humanos
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