Detection of Trisomy 21 using Deep Learning A midterm capstone project report submitted in partial fulfilment of the requirement for the award of the degree of Bachelor of Engineering in Electronics and Computers Engineering / Electronics and Communication Engineering Submitted By Puneet Gupta (Regn. No.:102115213) Tejas Malhotra (Regn. No.: 102115259) Anirudh Verma (Regn. No.:102165013) Abhiyudya Seth (Regn. No.: 102115144) Chetan Yenigalla (Regn. No.:102106178) Srinivasa Raghavan S (Regn. No.: 102115262) (Group No – 26) Under Supervision of Dr. Harpreet Vohra (Designation, ECED) Dr. Chandramohan Dhasarathan (Designation, ECED) Department of Electronics and Communication Engineering THAPAR INSTITUTE OF ENGINEERING & TECHNOLOGY, PATIALA, PUNJAB June 2024 DECLARATION We hereby declare that the capstone project group report title “Detection of Trisomy 21 using Deep Learning “is authentic record of our own work carried out at “Thapar Institute of Engineering and Technology, Patiala” as a Capstone Project in seventh semester of B.E. (Electronics & Communication Engineering), under the guidance of “Dr Harpreet Vohra and Dr Chandramohan Dhasarathan”, during January to May 2024. Date: NAME ROLL No. Puneet Gupta 102115213 Tejas Malhotra 102115259 Anirudh Verma 102165013 Abhiyudya Seth 102115144 Chetan Yanigalla 102106178 Srinivasa Raghavan S 102115262 SIGNATURE ACKNOWLEDGEMENT We would like to express our thanks to our mentors Dr Harpreet Vohra and Dr Chandramohan Dhasarathan. They have been of great help in our venture, and indispensable resources of technical knowledge. They are truly amazing mentors to have. We are also thankful to Dr. Kulbir Singh, Head of Electronics and Communication Department, and also our friends who devoted their valuable time and helped us in all possible ways towards successful completion of this project. We thank all those who have contributed either directly or indirectly to this project. Lastly, we would also like to thank our families for their unyielding love and encouragement. They always wanted the best for us and we admire their determination and sacrifice. Date: Roll No. Name 102115213 Puneet Gupta 102115259 Tejas Malhotra 102165013 Anirudh Verma 102115144 Abhiyudya Seth 102106178 Chetan Yenigalla 102115262 Srinivasa Raghavan S ii ABSTRACT Down Syndrome (DS) is a genetic disorder caused by an extra copy of chromosome 21, characterized by distinct facial features and associated medical conditions. This project focuses on developing a deep learning model for automated detection of DS using facial images, aiming to aid early and accurate diagnosis. We utilized a deep convolutional neural network (DCNN) to analyze facial patterns indicative of DS from a diverse and extensive dataset. Preprocessing techniques such as image normalization, augmentation, and alignment were applied to enhance data quality. The DCNN was trained with advanced methodologies, including transfer learning and hyperparameter optimization, to ensure high accuracy and robustness. Our model provides a non-invasive, quick, and reliable tool for detecting DS, potentially improving early intervention and care. Future work includes optimizing the model for edge devices like the Jetson Nano, enabling real-time analysis in resource-constrained environments. This approach promises to enhance clinical diagnostics and accessibility to healthcare for individuals with Down Syndrome. This non-invasive tool aids clinicians in prompt DS identification, improving care and treatment. Future work aims to optimize the model for real-time analysis on edge devices like the Jetson Nano, enhancing accessibility in resourcelimited settings. iii LIST OF TABLES Table No. Caption Page No. Table 2.1 Summary of face detection methods for DS face recognition. 9 Table 2.2 Datasets used by researchers for their studies [27]-[44] 11 Table 2.3 Methodology engaged in studies [28]-[44] 11 Table 4.1 Listo of UG subjects used in the project 18 vii LIST OF FIGURES Figure No. Caption Page No. Figure 2.1 Chromosomal Arrangement of Down Syndrome (Wikipedia) 1 Figure 2.2 Graphical representation of CNN Network 5 Figure 2.3 Classification model pipeline 8 Figure 2.4 Procedure of determining the feet structure indices 12 Figure 2.5 The structure of the proposed MLP model in literature [18] 13 Figure 3.1 Concept diagram for proposed system 16 Figure 5.1 Architecture of DCNN model 20 Figure 5.2 Tested Models and Train Test Accuracy 20 Figure 5.3 Confusion matrix of the CNN model 21 Figure 5.4 ROC Curve 21 viii LIST OF ABBREVATIONS TIET Thapar Institute of Engineering and Technology ECE Electronics and Communication Engineering DCNN Deep Convolutional Neural Networks AVSD Atrioventricular Septal Defects AD Alzheimer's Disease HD Hirschsprung's disease DST Duodenal Stenosis IA Imperforate Anus AMKL and ALL Leukaemia’s CHD Congenital heart defects NB Nasal Bone Length NT Nuchal Translucency MLP Multilayer Perceptron ROC Receiving operator characteristics IoT Internet of Things LDF Learning Deep Format CNN Convolutional Neural Network MTCNN Multitask Cascaded Convolutional Neural Networks FL Femur Length ADF Anisotropic Diffusion Filter ROI Region of interest AFP Alpha-Fetoprotein, hCG Human Chorionic Gonadotropin, and uE3 Unconjugated Estriol TABLE OF ix CONTENTS DECLARATION ACKNOWLEDGEMENT ABSTRACT LIST OF TABLES LIST OF FIGURES LIST OF ABBREVIATIONS CHAPTER 1- INTRODUCTION 1.1 PROJECT OVERVIEW 1.2 MOTIVATION 1.3 ASSUMPTIONS AND CONSTRAINTS 1.4 NOVELTY OF WORK CHAPTER 2 – LITERATURE SURVEY 2.1 LITERATURE SURVEY 2.2 RESEARCH GAPS 2.3 PROBLEM DEFINITION AND SCOPE CHAPTER 3 – FLOW CHART 3.1 SYSTEM ARCHITECTURE 3.2 ANALYSIS 3.3 TOOLS AND TECHNOLOGIES USED CHAPTER 4 – PROJECT DESIGN AND DESCRIPTION 4.1 DESCRIPTION 4.2 U.G SUBJECTS 4.3 STANDARDS USED CHAPTER 5 – IMPLEMENTATION & EXPERIMENTAL RESULT (OPTIONAL 5.1 SIMULATION RESULTS i ii iii iv v vi 1 1 1 2 2 3 3 14 14 16 16 16 16 18 18 18 19 20 20 CHAPTER 6 – OUTCOME AND PROSPECTIVE LEARNING 6.1 SCOPE AND OUTCOMES 6.2 PROSPECTIVE LEARNINGS 6.3 CONCLUSION CHAPTER 7 – PROJECT TIMELINE 7.1 WORK BREAKDOWN & GANTT CHART 7.2 PROJECT TIMELINE 7.3 INDIVIDUAL GANTT CHART 22 22 22 .22 24 24 24 24 REFERENCES 27 iv CHAPTER-1 INTRODUCTION 1.1 PROJECT OVERVIEW Down Syndrome (DS) is a genetic disorder caused by the presence of an extra chromosome 21. Early diagnosis of DS is crucial for timely intervention and management, which can significantly improve the quality of life for individuals with the condition. Traditional diagnostic methods often require specialized equipment and expertise, limiting accessibility, especially in low-resource settings. This project aims to address these limitations by developing an accurate and robust deep learning model capable of detecting Down Syndrome from facial images and optimizing it for deployment on edge devices, thereby enhancing accessibility and usability in diverse healthcare environments. The objectives are: Develop a Deep Learning Model: Create a convolutional neural network (CNN) that accurately detects Down Syndrome using facial images. Validate Model Performance: Evaluate the model's performance through extensive testing to ensure robustness and reliability in various conditions. Optimize for Edge Devices: Optimize the model to ensure it is lightweight and efficient enough to run on edge devices, such as smartphones and tablets, without compromising accuracy. Ensure Usability for Non-Specialists: Design the model and its interface to be user-friendly, enabling non-specialist healthcare providers to effectively use the tool. By the end of this project, we are expected to have a deep learning model that reliably detects Down Syndrome with high accuracy from facial images, an optimized model that operates efficiently on edge devices, making it accessible for use in various healthcare settings, including those with limited resources, an intuitive interface that enables non-specialist healthcare providers to use the diagnostic tool effectively, enhanced diagnostic capabilities for Down Syndrome, particularly in remote and underserved areas, contributing to earlier diagnosis and better management of the condition. 1.2 MOTIVATION Down syndrome (DS) is one of the most common genetic birth disorders. Down syndrome occurs in approximately 1 of 830 live births. It is associated with mild to moderate learning disabilities, developmental delays, characteristic facial features, and low muscle tone in early infancy. Many individuals with Down syndrome also have heart defects, leukaemia, early-onset Alzheimer’s disease, gastro-intestinal problems, and other health issues. Through a series of screenings and tests, Down syndrome can be detected before and after a baby is born. This project aims to empower non-specialist healthcare providers with the tools needed to detect Down Syndrome (DS) in children at the earliest possible stage. Though Down syndrome can’t be prevented, it can be detected in earlier stages. The health problems that may go along with DS can be treated, and many resources are available to help kids and their families who are living with the condition. By equipping non-specialist healthcare providers with an accurate, robust, and user-friendly diagnostic tool, this project seeks to bridge the gap in access to specialized medical expertise, particularly in underserved and remote areas. By developing and optimizing a deep learning-based diagnostic tool that can run efficiently on edge devices such as smartphones and tablets, this project aims to make advanced diagnostic capabilities accessible to a broader range of healthcare providers. This accessibility is particularly important in regions where access to specialized medical professionals and diagnostic equipment is limited. The 1 tool's ease of use will allow non-specialist healthcare providers, such as general practitioners, nurses, and community health workers, to perform preliminary screenings and identify children who may need further evaluation and support. In summary, this project strives to democratize access to early Down Syndrome detection, ensuring that every child has the opportunity to receive the care and support they need from the very beginning. By leveraging the power of deep learning and edge computing, we aim to create a transformative impact on the early diagnosis and management of Down Syndrome, ultimately contributing to better health outcomes and enhanced quality of life for children and their families. 1.3 ASSUMPTIONS AND CONSTRAINTS One primary assumption is that facial features are a reliable indicator for detecting Down Syndrome, which is supported by existing medical research. The project also assumes that the dataset collected will be representative of the diverse population of children with DS, ensuring the model's applicability across different ethnicities. Constraints include the limited computational power of edge devices like the Jetson Nano and Raspberry Pi, which necessitate model optimization techniques such as quantization and compression. Additionally, the project is constrained by the availability of labeled data, requiring the use of data augmentation to enhance the dataset. These assumptions and constraints are critical to defining the project's scope and ensuring that the developed model is both effective and practical for real-world deployment 1.4 NOVELTY OF WORK While numerous studies have focused on developing robust deep learning models for the detection of Down Syndrome (DS) using facial images, there remains a significant gap in research and practical implementation regarding the deployment of these models on edge devices such as the NVIDIA Jetson Nano and Raspberry Pi. This project introduces a novel approach by not only developing a highly accurate deep learning model for DS detection but also optimizing and deploying it on these edge devices. Unlike traditional implementations that rely on powerful cloud-based servers, this project addresses the unique challenges of running deep learning models on devices with limited processing power, memory constraints, and energy efficiency. By leveraging innovative techniques in model compression and quantization, the project ensures efficient operation on these compact and affordable devices. This deployment enhances accessibility and portability, enabling non-specialist healthcare providers to use advanced diagnostic tools in diverse settings, including remote and underserved areas. The project emphasizes creating a user-friendly interface for easy image capture and analysis, allowing real-time processing and immediate diagnostic feedback, which is crucial for timely intervention. Moreover, the cost-effectiveness of these edge devices reduces financial barriers, making advanced diagnostic technology viable for widespread adoption, particularly in low-resource settings. By focusing on scalability and practical deployment strategies, this project not only extends the capabilities of deep learning-based DS detection but also sets a precedent for future research and applications of deep learning in healthcare on edge devices. 2 CHAPTER-2 LITERATURE SURVEY 2.1 LITERATURE SURVEY 2.1.1 Introduction Down syndrome, clinically known as Trisomy 21, is a genetic disorder caused by the presence of an extra copy or part of chromosome 21. It is one of the most commonly occurring chromosomal abnormalities, affecting approximately 1 in 700-1,000 live births worldwide. Individuals with Down syndrome exhibit a distinct set of physical characteristics, including craniofacial dysmorphologies, intellectual disability, and a higher predisposition to certain medical conditions. Fig. 2.1 Chromosomal Arrangement of Down Syndrome (Wikipedia) 1. Common Features of Down Syndrome (DS): Learning disabilities, craniofacial abnormalities, and hypotonia. Variant phenotypes may include atrioventricular septal defects (AVSD), leukaemia, Alzheimer's disease (AD), and hypertension. 2. Physical Characteristics: 3 Slanted eyes, poor muscle tone, and a flat nasal bridge. Additional features: single palm crease, protruding tongue, and abnormalities in toe size and fingerprint patterns. 3. Genetic Causes: Trisomy of chromosome 21 (most common), Robertsonian translocation, and mosaicism. Genetic hypotheses: gene dosage imbalance, amplified developmental instability, and critical region hypotheses. 4. Associated Clinical Conditions: Neurological Problems: Early-onset Alzheimer's disease (AD). Cardiac Problems: Congenital heart defects (CHD). Haematological Problems: Leukaemia’s (AMKL and ALL). Gastrointestinal Problems: Hirschsprung's disease (HD), duodenal stenosis (DST), and imperforate anus (IA). Various factors influence the risk of Down syndrome (DS), including maternal grandmother's diet, genotype, lifestyles, and environmental exposures, which can impact recombination errors leading to chromosome 21 nondisjunction during fetal development. Maternal age at conception, along with maternal diet, lifestyle, and environmental factors, can favor meiotic errors, particularly at maternal meiosis II, contributing to DS cases. Paternal dietary habits, lifestyles, and environmental exposures may influence chromosome 21 disomy in spermatozoa, leading to cases of paternal origin DS. Complex interactions between the embryo's genome, maternal factors, and environmental exposures can affect the outcome of DS pregnancies, including miscarriage, survival to birth, congenital disorders, or predisposition to age-related diseases in DS individuals. Early and accurate diagnosis of Down syndrome is crucial for prompt interventions, tailored educational programs, and appropriate medical management. Traditional diagnostic methods involve prenatal screening tests, such as maternal serum screening and ultrasound examinations, followed by invasive procedures like amniocentesis or chorionic villus sampling for cytogenetic analysis. However, these methods are often time-consuming, resource-intensive, and carry potential risks. With the rapid advancement of artificial intelligence (AI) and computer vision techniques, there has been a growing interest in developing non-invasive, automated systems for detecting Down syndrome based on facial analysis. Individuals with Trisomy 21 often exhibit characteristic facial features, including a flattened facial profile, up slanting palpebral fissures, and a protruding tongue. Deep learning models, particularly convolutional neural networks (CNNs), have demonstrated remarkable success in recognizing complex patterns and subtle features in images, making them well-suited for this task. The development of an accurate and reliable AI model for Trisomy 21 identification from facial images presents several challenges. First, acquiring a diverse and representative dataset of facial images from individuals with and without Down syndrome is crucial for robust model training and generalization. Handling variations in imaging conditions, such as pose, illumination, and occlusions, is another critical aspect to ensure model performance across different scenarios. Furthermore, ensuring fairness and robustness across different populations is essential, as biases in the training data or model architecture could lead to disparate performance and potential ethical concerns. Interpreting the model's decision-making process and identifying the specific facial features that contribute to the diagnosis is also crucial for clinical acceptance, transparency, and potential integration with existing diagnostic protocols. Overcoming these challenges requires a multidisciplinary approach, combining expertise from various fields, including computer vision, machine learning, genetics, and clinical practice. Successful development and deployment of such AI models could potentially streamline the diagnostic process, reduce the need for invasive procedures, and facilitate early interventions for individuals with Down syndrome. This 4 article aims to provide a comprehensive review of the current state-of-the-art in AI model development for Trisomy 21 identification from facial images. We will explore the various techniques, datasets, and methodologies employed, as well as the challenges and limitations encountered. Additionally, we will discuss potential avenues for future research and the ethical considerations surrounding the use of AI in genetic disorder diagnosis. This study synthesizes findings from various research papers and studies, utilizing multiple techniques to develop an AI model for identifying Trisomy 21 from facial features. The various methodologies, such as deep learning architectures, data preprocessing steps, and classification algorithms, along with their performance metrics, accuracies, and limitations, are examined in different sections of this article. 2.1.2 Deep Learning Techniques for Medical Imaging A. Convolutional Neural Networks (CNNs) Convolutional Neural Networks (CNNs) are a type of deep neural network architecture that is particularly well-suited for processing image data. CNNs are designed to automatically learn and extract relevant features from input images through multiple layers of convolutional, pooling, and fully connected layers. 1. Convolutional Layer: This layer applies a set of learnable filters (kernels) that slide across the input image, performing convolution operations to extract local features such as edges, shapes, and patterns. 2. Pooling Layer: This layer performs down-sampling operations on the feature maps, reducing their spatial dimensions while retaining the most important information. Common pooling operations include max pooling and average pooling. 3. Fully Connected Layer: These layers are similar to traditional neural networks, where every node is connected to all nodes in the previous layer. They are responsible for combining the features learned by the convolutional and pooling layers and making the final classification or regression decision. Fig. 2.2 Graphical Representation of CNN network CNNs have been extensively applied in various medical image analysis tasks, including: 1. Image Classification: Classifying medical images into different categories, such as normal or abnormal, or identifying specific diseases or conditions. 5 2. Object Detection and Localization: Detecting and localizing regions of interest within medical images, such as tumors, lesions, or anatomical structures. 3. Segmentation: Partitioning medical images into different regions or structures, enabling precise delineation of target areas for further analysis or treatment planning. 4. Image Registration: Aligning and matching different medical images, which is crucial for multimodal analysis, longitudinal studies, and image-guided interventions. 5. Image Enhancement: Improving the quality of medical images by reducing noise, enhancing contrast, or normalizing intensity distributions. B. Transfer Learning Transfer learning is a technique where a deep learning model pre-trained on a large, general dataset is used as a starting point for a new task, rather than training from scratch. The pre-trained model's weights are fine-tuned on the target dataset, allowing the model to leverage the knowledge gained from the initial training and adapt to the new task more efficiently. In the context of medical diagnostics, transfer learning offers several advantages: 1. Limited Data: Medical datasets are often small and limited due to privacy concerns and the difficulty of data collection. Transfer learning allows leveraging knowledge from large, general datasets, reducing the need for extensive labeled medical data. 2. Faster Convergence: Pre-trained models provide a good initialization point, enabling faster convergence and reducing training time compared to training from scratch. 3. Improved Performance: By leveraging the knowledge from related domains, transfer learning can improve the performance of medical diagnostic models, especially when the target dataset is small. Transfer learning has been successfully applied in various healthcare applications, including: 1. Radiology: Pre-trained models on natural images have been fine-tuned for tasks such as chest X-ray analysis, brain tumor segmentation, and mammogram classification. 2. Dermatology: Models pre-trained on general image datasets have been adapted for skin lesion classification and melanoma detection. 3. Ophthalmology: Transfer learning has been used for retinal image analysis, including diabetic retinopathy detection and age-related macular degeneration diagnosis. 4. Pathology: Pre-trained models have been fine-tuned for tasks like cancer histopathology image classification and tumor grading. C. Model Training and Validation Training deep learning models for medical imaging applications requires high-quality, diverse, and well-annotated datasets. However, obtaining such datasets can be challenging due to the following factors: 1. Data Privacy and Ethical Concerns: Medical data is highly sensitive, and strict regulations and ethical guidelines must be followed to protect patient privacy and ensure proper consent. 2. Limited Data Availability: Collecting and annotating medical images is a time-consuming and resource-intensive process, often leading to small dataset sizes. 3. Class Imbalance: In many medical imaging tasks, the distribution of different classes (e.g., normal vs. abnormal) can be highly imbalanced, which can affect model performance. 6 4. Data Diversity: Medical imaging data can vary significantly based on factors such as patient demographics, imaging modalities, and acquisition protocols, making it crucial to have diverse and representative datasets. Several techniques are employed to train deep learning models for medical imaging effectively: 1. Data Augmentation: Techniques like rotation, flipping, scaling, and adding noise can be used to artificially increase the size and diversity of the training dataset. 2. Transfer Learning: As discussed earlier, transfer learning from pre-trained models on large, general datasets can significantly improve model performance and convergence speed. 3. Ensemble Methods: Combining multiple models trained on different subsets of the data or with different architectures can improve overall performance and robustness. 4. Regularization: Techniques like dropout, weight decay, and early stopping can help prevent overfitting and improve model generalization. 5. Attention Mechanisms: Incorporating attention mechanisms into the model architecture can help focus on the most relevant regions of the input image, improving performance on tasks like object detection and segmentation. Proper validation is crucial to ensure the accuracy and reliability of deep learning models for medical imaging: 1. Cross-Validation: Techniques like k-fold cross-validation can be used to estimate the model's performance on unseen data and prevent overfitting. 2. Independent Test Sets: Holding out a separate test set, ideally from a different distribution than the training data, can provide an unbiased evaluation of the model's performance and generalization ability. 3. Human Expert Evaluation: Involving medical experts to evaluate the model's predictions and compare them with ground truth annotations can provide valuable insights and identify potential biases or errors. 4. Robustness Testing: Evaluating the model's performance under various conditions, such as different imaging modalities, noise levels, or perturbations, can help assess its reliability and identify potential failure modes. 5. Explainable AI Techniques: Methods like saliency maps, attention visualization, and concept activation vectors can help interpret and explain the model's decision-making process, increasing trust and transparency in medical applications. By following best practices in dataset curation, model training, and validation, deep learning techniques can be effectively applied to medical imaging tasks, potentially improving diagnostic accuracy, treatment planning, and patient outcomes. 2.1.3 Deep Learning Techniques in Detecting Down Syndrome A. DS Detection using Facial Images 7 Fig. 2.3 Classification model pipeline [26] The training algorithm comprises three stages: image preprocessing, training a general facial recognition network, and fine-tuning the network for the specific task of Down syndrome identification.[26] The core foundation of this approach lies in leveraging the power of deep convolutional neural networks (DCNNs) to extract the subtle yet distinct facial features that differentiate individuals with Down syndrome from their neurotypical counterparts. Image Preprocessing Effective image preprocessing is a crucial step in the Down syndrome identification pipeline, as it ensures that the input data is optimized for accurate facial detection and feature extraction by the neural network. The image preprocessing routine employed in this study encompasses four main stages: image enhancement, facial detection, facial cropping, and image resizing. Image Enhancement The raw images used in this study are acquired in unconstrained real-world settings, leading to significant variability in exposure, contrast, and imaging conditions. To mitigate the impact of these extraneous factors and enable the subsequent facial detection algorithms to operate optimally, image enhancement techniques are applied. The image enhancement process serves two critical purposes. Firstly, it facilitates superior facial area detection in the subsequent steps by enhancing the visibility and contrast of facial regions. Secondly, it minimizes the influence of irrelevant factors such as exposure, contrast, and camera characteristics, enabling the neural network to concentrate more effectively on the intrinsic facial features relevant to Down syndrome identification. Facial Detection After image enhancement, a robust and highly accurate facial detection algorithm is employed to locate the precise position of the face within the image. This step is crucial, as it isolates the facial area from the background, allowing the subsequent stages to focus solely on the relevant facial features. Given the inherent variability in unconstrained 2D facial images, including differences in face sizes, expressions, and backgrounds, a deep learning-based approach is adopted for facial detection. Specifically, the multitask cascaded convolutional neural networks (MTCNN) technique is utilized, as it has demonstrated state-of-the-art performance in facial detection tasks. The MTCNN approach consists of three cascaded convolutional neural networks: P-Net, R-Net, and ONet. These networks work in a sequential manner, with each stage refining the facial detection results from the previous stage. The P-Net network performs an initial face candidate detection, the R-Net network filters and refines these candidates, and the O-Net network generates the final bounding box coordinates and facial landmarks for each detected face. To adapt the MTCNN model to the specific requirements of this study, the pre-trained network is fine-tuned using a subset of the available facial images. This customization process ensures that the facial detector is optimized for 8 the diverse range of facial characteristics, expressions, and imaging conditions present in the Down syndrome identification dataset. Facial Cropping Once the precise location of the face is determined by the facial detection algorithm, the facial region is cropped from the enhanced image. This cropping step serves two primary purposes. Firstly, it isolates the facial area from the background, ensuring that the subsequent neural network focuses solely on the relevant facial features and is not influenced by extraneous background information. By concentrating on the facial region, the network can learn to extract the subtle phenotypic features that distinguish individuals with Down syndrome from healthy individuals more effectively. Secondly, the facial cropping process helps to standardize the input data, as the cropped facial images are typically of varying sizes and aspect ratios. This standardization is essential for compatibility with the input requirements of the neural network architecture employed in the Down syndrome identification task. Image Resizing By standardizing the input image dimensions, the neural network can process batches of images efficiently, without the need for additional resizing or interpolation operations during training or inference. This consistency in input data format contributes to improved training stability and convergence, as well as faster processing times during real-world deployment. In summary, the image preprocessing routine employed in this study is a multi-stage process designed to optimize the input data for accurate facial detection and feature extraction. By enhancing image quality, locating and isolating the facial region, and standardizing the input dimensions, this preprocessing pipeline ensures that the neural network receives high-quality, relevant data, enabling it to learn the subtle phenotypic features associated with Down syndrome more effectively. Ref Databases Total Images DS Images Landmarks Detection Methods [45] Healthy & 8 known disorders including DS Healthy & 8 known disorders including DS Healthy & DS 2878 209 36 OpenCV 154 50 44 ViolaJones(Haar like) 261 129 44 6 known syndromes including DS Healthy & DS 1126 537 68 ViolaJones(Haarlike) PASCAL VOC 306 153 16 216 known syndromes including DS 17,000 - 130 [46] [47] [48] [49] [50] ViolaJones(Haarlike) DCNN cascade Table 2.1 Summary of face detection methods for DS face recognition. 9 B. DS Detection using Ultrasound Images Ultrasonography is a widely adopted medical imaging method that allows real-time visualization of the abdominal region (Orlandi et al. 2003). It utilizes high-frequency sound waves, above the audible range for humans, to detect and measure objects within the body. Despite being based on sound waves, this imaging technique is considered safe and does not have any negative impact on the human body (Lao et al. 2019). Consequently, it is recommended for pregnant women to monitor fetal growth. Several biomarkers, such as nasal bone (NB) length, nuchal translucency (NT), femur length (FL), crown-rump length (CRL), and fronto-maxillary facial angle, are commonly used to identify potential cases of Down syndrome through ultrasound imaging (Ghonchi et al. 2020). Nuchal translucency refers to the accumulation of fluid at the back of the fetal neck, and this measurement is typically taken during the 12th week of pregnancy. A normal nuchal translucency value falls within the range of 1.30 ± 0.54, while values exceeding 2.5 are considered abnormal, indicating a potential irregularity (More and Singla 2021). On the other hand, nasal bone length is another important marker, with normal values ranging from 1.69 mm to 2.94 mm. In cases where the nasal bone is absent or not visible, it may signify an abnormality in the fetus (Park et al. 2013; Wee et al. 2010). While ultrasound imaging offers valuable visual information about the fetus, manually analyzing and classifying the nuchal translucency (NT) and nasal bone (NB) features can be a time-intensive and inefficient process. Neural networks, a machine learning technique, have demonstrated remarkable capabilities in accurately classifying medical images, offering a promising solution to streamline and automate this process (Chaudhary et al. 2019). The foetal images are pre-processed using anisotropic diffusion filter (ADF) which removes highfrequency noise while preserving existing objects’ main edges The pre-processed foetal images are subjected to region of interest (RoI) extraction to isolate the Down syndrome makers from the ultrasound image Sensitivity, specificity, accuracy, recall, and F1 score are the evaluation metrics for evaluating the efficiency of the proposed method. Author Dataset used Bharath Srinivas prabakaran et al. FPUS23dataset https://github.com/bharathprabakaran/FPUS2 Ellen Hollands Steffensen et al. Danish Medical Birth Register Liwen Zhang et al. Collected data from 2 hospitals in China (Jan 2009 – Sept 2020) Li Li et al. Collected data from obstetric clinic of their hospital from Jan 2019 – Dec 2021 Luis M LopezGarcia et al. Data from pregnant women in Spanish hospitals. Amir Jamshid Nezhad et al. private screening reference laboratory Falin He et al. 58,972 screening data over 10 years were used to establish a machine model to predict Down syndrome 10 Bosheng Qin et al. CASIA-WebFace datasets Alptekin Durmus ̧o ̆ glu et al. From Gaziantep University’s S ̧ ahinbey Training and Research Hospital, 81 patient records were obtained in Turkey. Anita Kaul et al The data was collected between the years 2010 and 2017 from singleton Indian women who had fetal ultrasound, with measures of the fetal NT thickness and CRL during 11 and 13 + 6 weeks of pregnancy. Ling Li et al maternal serum screening data. Chanane Wanapirak et al. maternal serum screening among Thai population Prim Dr Sc med Jasmina Durkovi ́ c et al. Leveraging the IMMULITE 2000 analyser, data were produced. Aki Koivu et al. Multiple categorization techniques have been explored with using two real-world data sets. Bing Feng et al Illumina genotyping array data Subhiksha Ramanathan et al. Subhiksha Ramanathan Hospitals, Solapur, Maharashtra Bing Feng et al. Vanderbilt University Medical Centre Table 2.2 Datasets used by researchers for their studies [27]-[44] Methodology Used Description ResNet34 Model Demonstrated remarkable accuracy in classifying diagnostic planes, achieving approximately 98.29% accuracy. Faster-RCNN Model with base of ResNet34 Model Dedicated to detecting the anatomical bounds of the foetus within ultrasound images, showcasing precision in analysis. Temporal Developments Analysis Evaluated temporal developments in data, particularly through interrupted time series studies, enhancing understanding of the impact of the national prenatal screening program on birth biometry, congenital abnormalities, and early childhood morbidity. DL Model for Fetal Head Segmentation Focused on the fetal head region within ultrasonographic images, successfully segmented images using bounding boxes and applied data augmentation techniques to create additional training data. Diagnostic Methods Employed various diagnostic methods, including ultrasonographic diagnosis, serological screening, and genetic counselling for prenatal diagnosis, involving measurements of nuchal translucency thickness, analysis of maternal blood for specific markers, and genetic counselling and amniocentesis for high-risk pregnancies 11 Unified Multivariate Bayesian Model Predicted Down syndrome using a unified multivariate Bayesian model, risk based on biochemical and ultrasound parameters, calculating likelihood ratios for affected and unaffected foetuses and combining them with prior risk (related to maternal age) to determine patient specific Down syndrome risk. Genetic techniques and artificial neural networks (ANN) Deployed an artificial neural network, also known as an ANN, to predict the probability of Down syndrome in foetuses through the examination of input data such as hormone levels, foetal measures, and woman age. The framework and characteristics of the ANN, such as the number of neurons in hidden layers, transferred functions, training operations, acquiring functions, and inputs factor selection, were optimised using the GA. Convolutional Neural Network (CNN) implemented a convolution neural network, also known as CNN, to determine individuals with Down syndrome with an emphasis on 2D RGB face picture classification. obtained a binary categorization with the likelihood of having Down syndrome (healthy or with Down syndrome). Table 2.3 Methodology engaged in studies [28]-[44] C. DS Detection using Feet Deformities The "sandal gap" is a phenomenon in which, due to the lack of a restrictive toe box in sandals, the toes can actuate unrestricted, so one may end up with any number of aligned and misaligned toes. Fifty-five subjects with DS (age: 14.6 ± 7.4 years) had undergone podiatric clinical and podoscopic examinations to study their main foot deformities and their footprints, respectively. The results of these examinations were compared to those of an age-matched asymptomatic control group of fiftythree subjects (age: 13.4 ± 11.2 years). Despite the reported high prevalence of foot anomalies in DS populations, the current literature is far from being exhaustive and does not include investigations on other foot deformities such as hallux varus, overriding fifth toe (quintus varus supraductus), short metatarsals and metatarsus adductus. Fig 2.4 Procedure for determining the feet structure indices: (a) foot length (D), foot width (S), and the Wejsflog (W) index; (b) Clarke's angle; (c) hallux valgus angle (α) and the angle of the varus deformity of the fifth toe (β).[2] 12 This large age range reveals the wide spectrum of foot deformities associated with the different age groups of subjects with DS with, for instance, significantly increased odds of presenting an increased space between the first and second toes and short metatarsals with increasing age. However, the different ages of the patients might also reveal the same deformity at different stages of its natural evolution. Larger groups of patients with DS of different ages or a long-term longitudinal study would better elucidate the natural history of these deformities. Although many of the reported deformities in this study are described in the literature, hallux valgus, increased space between the first and second toes, syndactyly, and higher grades of flatfoot were found to be more prevalent in subjects with DS compared to a control group. Some deformities, among which increased space between the 1st and 2nd toes, were found to be significantly related to general factors such as age, presence of joint laxity and BMI. D. DS Detection using Blood Test The triple test is a screening test (blood test) used to calculate the probability of a pregnant woman having a fetus that has a chromosomal abnormality like Down Syndrome (DS). AFP (AlphaFetoprotein), hCG (Human Chorionic Gonadotropin), and uE3 (Unconjugated Estriol) values in the blood sample of pregnant women are computed and compared with the similar real records where the outputs (healthy fetus or a fetus with DS) are actually known. The likelihood of the indicators is used to calculate the probability of having a fetus with chromosomal abnormality like DS. It is a blood test typically performed during the second trimester and these three markers are used in combination to modify the maternal age-related risk of DS and thus determine individual risk of fetal DS. In the calculation of associated risk, maternal age-related risk is multiplied by likelihood ratios, determined according to the deviation of the measured levels of three markers from the expected median values. The MLP model developed for this study employs three input variables that are AFP, hCG and uE3 to predict target class (as DS and DS free). We have not used the weight and gestational week attributes due to multiple missing values in the records. The training phase adjusts the internal weights to get as close as possible to the known class’s values. As illustrated in Figure, node 0 and node 1 are output nodes and node 2 and node 3 are hidden nodes. Fig. 2.5 The structure of the proposed MLP model in literature [18] 13 2.3 RESEARCH GAPS While conducting a thorough review of the literature on Down Syndrome (DS) prediction, two significant research gaps have emerged that this project aims to address. Limited Dataset on Indian Children with Down Syndrome One of the primary challenges in developing accurate and robust deep learning models for DS detection is the availability of diverse and representative datasets. Current studies predominantly focus on datasets from Western populations, resulting in a lack of representation for other ethnic groups, including Indian children. This limitation is significant because facial features associated with DS can vary across different ethnicities. Consequently, models trained on non-representative datasets may not generalize well to Indian children, leading to potential inaccuracies and reduced diagnostic efficacy in this demographic. Addressing this gap requires the collection and inclusion of a comprehensive dataset of Indian children with DS to ensure the developed model can accurately detect DS across diverse populations. Lack of Research on Implementing DS Detection Models on Edge Devices Another critical gap identified is the absence of research focused on deploying DS detection models on edge devices such as the Raspberry Pi and NVIDIA Jetson Nano. While numerous studies have successfully developed deep learning models for DS detection using facial images, these models typically rely on cloud-based servers with substantial computational resources. This reliance poses significant barriers to accessibility and practical implementation, particularly in low-resource settings where advanced infrastructure may be lacking. Edge devices offer a promising solution by providing portable, cost-effective, and efficient alternatives for deploying these models. However, the unique challenges associated with optimizing deep learning models to run on devices with limited processing power and memory have not been sufficiently addressed in the literature. Bridging this gap involves developing techniques for model compression and quantization, ensuring that these models maintain high accuracy while being capable of running efficiently on edge devices. 2.4 PROBLEM DEFINITION AND SCOPE Problem Statement Despite significant advancements in the development of deep learning models for the detection of Down Syndrome (DS) using facial images, there are notable limitations and gaps in current research and practical implementation. One primary issue is the lack of a diverse and representative dataset, particularly concerning Indian children with DS, which hinders the generalizability and accuracy of existing models across different ethnic groups. Additionally, there is a significant gap in the deployment of these models on edge devices such as the Raspberry Pi and NVIDIA Jetson Nano. Current models typically rely on cloud-based servers, which are not practical for use in low-resource settings due to their high cost and need for substantial computational resources. These gaps create a barrier to early, accessible, and accurate diagnosis of DS, particularly in underserved and remote areas. Scope The scope of this project encompasses several key areas aimed at addressing the identified problem statement. It involves collecting and curating a comprehensive dataset of facial images of Indian children with and without Down Syndrome to ensure diverse representation and enhance model generalizability across different ethnicities. The project will develop a robust convolutional neural network (CNN) model tailored for DS detection using this dataset, implementing data augmentation and regularization techniques to improve accuracy. Additionally, the project focuses on optimizing the 14 model for deployment on edge devices like the Raspberry Pi and NVIDIA Jetson Nano, employing techniques such as model compression and quantization to ensure efficient operation on devices with limited computational power and memory. A user-friendly interface will be designed to enable nonspecialist healthcare providers to easily capture and analyse facial images, supporting real-time processing and immediate diagnostic feedback. Extensive validation and robustness testing will be conducted to ensure high accuracy and practical applicability. 15 CHAPTER-3 FLOW CHART 3.1 SYSTEM ARCHITECTURE Camera will be used to capture images. Those images will then be transferred to jetson nano. Images received from the camera will be processed and then are used to predict Trisomy 21 Fig. 3.1 Concept diagram for proposed system 3.2 ANALYSIS We begin with the architectural design of the Convolutional Neural Network (CNN), detailing how various layers and parameters were chosen to enhance model performance. The dataset, consisting of facial images of children with and without DS, is pre-processed using data augmentation techniques to increase diversity and improve the model's generalizability. Several metrics, such as accuracy, precision, recall, and F1-score, are used to evaluate the model's effectiveness. Additionally, confusion matrices are generated to identify potential areas of misclassification, allowing for further fine-tuning of the model. Transfer learning techniques are employed to leverage pre-trained models, significantly reducing training time and improving accuracy. The integration of Tensor RT and OpenCV libraries further optimizes the model for real-time applications on edge devices like the Jetson Nano/Raspberry Pi, demonstrating the feasibility of deploying advanced AI diagnostics in resource-limited settings. 3.3 TOOLS AND TECHNOLOGY USED 1. Python: Python serves as the primary implementation language, owing to its ease of use and extensive libraries. We can utilize Python's extensive ecosystem to create an end-to-end data pipeline, encompassing data preparation and model implementation, through the use of Python programming. With this capability, there is an effortless connection to diverse libraries and architectures, resulting in a harmonious and extensible solution for detecting drowsiness. 2. TensorRT: It is a high-performance deep learning inference library that plays a crucial role in production environments, offering significant speedups and efficiency improvements over 16 traditional CPU-based inference methods This technology finds significant application in various fields such as autonomous vehicles, natural language processing, computer vision, and recommendation systems. 3. Transfer learning : It is a powerful approach for building image classification models, which capitalizes on pre-trained models trained on extensive datasets. By utilizing pre-trained weights to initialize the model, the training process can be optimized, and the model can reap the benefits of the knowledge acquired from the foundational dataset. It offers faster training times, improved accuracy, and suitability for resource-limited devices. 4. OpenCV: It is a powerful open-source computer vision and machine learning software library. The objective is to offer a comprehensive collection of tools and algorithms for the processing and interpretation of visual data, including images and videos. It is designed to operate effectively on a range of platforms, including Windows, Linux, macOS, Android, and iOS. With interfaces for Python and Java, this tool caters to a broad developer community. 5. Tensor Flow: TensorFlow serves as an open-source framework for the creation and implementation of machine learning models. This ecosystem provides a rich set of tools, libraries, and resources to support the development of a broad spectrum of machine learning applications, from basic linear regression models to advanced deep neural networks. This is a widely chosen development tool on account of its flexibility, scalability, and comprehensive features. 6. Jetson Nano: Jetson Nano is a small, powerful computer developed by Nvidia specifically designed for embedded applications and artificial intelligence (AI) at the edge. Deploying deep learning models and AI algorithms in resource-constrained environments is made easier by its compact form factor and GPU-accelerated computational capacity. It is well-suited for a variety of applications, such as autonomous vehicles, drones, smart cameras, and industrial automation, thanks to its mix of GPU acceleration, CPU performance, memory capacity, and I/O capacities. 7. Docker: The software deployment landscape experiences a radical shift with Docker's containerization technology, as it packages applications and their dependencies into lightweight, portable containers, ensuring a uniform environment and simplifying deployment processes. These containers hold the application code, its essential dependencies (libraries, system tools), and configurations, allowing for a reliable and unified execution across varying environments. With their harmonic combination of scalability, consistency, and efficiency in software delivery, these containers represent a paradigm change. 17 CHAPTER-4 PROJECT DESIGN AND DESCRIPTION 4.1 DESCRIPTION This project proposes a system to detect Down syndrome using a trisomy 21 classifier. The system leverages a Jetson Nano/Raspberry Pi module for image processing. Image Acquisition: The system will use a dedicated camera. User Interface: The results could be displayed on a screen. Operation: The system might be triggered by a button press, voice command, or another user input method instead of automatic image capture upon app launch. 4.2 U.G. SUBJECTS Subject Code UNC504 Subject Name Artificial Intelligence Description This subfield of AI equips the system to analyze visual data from the camera feed. Techniques like image segmentation and object detection will be used to isolate the driver's face within the frame. UCS668 Edge AI and Robotics: Data Vision Utilising methodologies including image processing, object detection, facial recognition, and feature extraction to examine visual data. UCS671 Edge AI and Robotics: Embedded Introduction to Edge computing and Jetson Vision kits. Understand GPU computing for building advanced computer vision pipelines on Jetson devices. UCS664 Conversational AI: Natural Language Applying pattern recognition, machine Processing learning algorithms, and real-time decisionmaking processes to accurately forecast driver weariness. UCS622 Conversational Ai: Accelerated Data Utilising sophisticated data science Science [Advanced] techniques, such as predictive modelling, statistical analysis, and machine learning, to analyse and understand extensive information in order to enhance the precision and dependability of sleepiness detection. Table 4.1 List of all the UG subjects used in the project 18 4.3 STANDARDS USED IEEE 610.4-1990 - Standard Glossary of Image Processing and Pattern Recognition Terminology: Provides a standardized set of terms for image processing and pattern recognition, assisting in clear communication and understanding within the context of down syndrome detection. IEEE P1451.99 - Standard for Harmonization of Internet of Things (IoT) Devices and Systems: Establishes a framework for seamless integration and interoperability of IoT devices and systems, enhancing the efficiency and coordination of components used in down syndrome detection applications. IEEE 1855™ - Standard for Learning Data Format (LDF): Provides a standardized set of terms for image processing and pattern recognition, assisting in clear communication and understanding within the context of down syndrome detection. IEEE P2841™ - Framework and Process for Deep Learning Evaluation: Defines a standardized framework and process for evaluating deep learning models, ensuring rigorous assessment and benchmarking of algorithms employed in down syndrome detection systems to enhance reliability and performance. 19 CHAPTER-5 IMPLEMENTATION AND EXPERIMENTAL RESULTS 5.1 SIMULATION RESULTS Fig 5.1 Architecture of CNN model Fig 5.2 Tested Models and Train Test Accuracy 20 Fig. 5.3 Confusion matrix of the CNN model Fig. 5.4 ROC curve 21 CHAPTER-6 OUTCOMES AND PERSPECTIVE LEARNING 6.1 SCOPE AND OUTCOMES The project aims to bridge the gap in early DS detection by developing a deep learning model that is not only accurate but also optimized for deployment on edge devices. The outcomes of this project are multifaceted. Firstly, there is a significant advancement in the understanding and application of CNNs for medical image recognition. The project also contributes to the practical knowledge of integrating AI models with hardware, enhancing the accessibility of advanced diagnostic tools in low-resource settings. Key outcomes include the creation of a user-friendly app developed using Flutter, which allows non-specialist healthcare providers to utilize this technology effectively. Furthermore, the project sets a precedent for future research by addressing the challenges of model optimization and hardware integration, ultimately improving early diagnosis and management of Down Syndrome in diverse healthcare environments. 6.2 PERSPECTIVE LEARNINGS This project on Trisomy 21 Detection with Deep learning and implementing on embedded device presents a valuable opportunity for developing a practical system and gaining significant knowledge and experience in various domains. ● Deep Learning Techniques: Understanding of Convolutional Neural Networks (CNNs) for image recognition and their application in down syndrome detection. ● OpenCV and Computer Vision: Gaining proficiency in OpenCV libraries for image processing and feature extraction, crucial for real-time detection. ● Model Optimization: Learning how to optimize trained neural network for efficient deployment on embedded device. ● Hardware Integration: Understanding the process of integrating the trained and optimized model with embedded devices. ● App Development: Understanding and learning how an app can be developed for handling deep learning model using Flutter ● Project Management and Collaboration: Refining project management skills through effective task allocation, progress tracking, and teamwork throughout the development process By successfully completing this project, the team will not only build a working drowsiness detection system but also gain valuable knowledge and experience transferable to future projects in computer vision, machine learning, and embedded systems development. 6.3 CONCLUSION This review provides a comprehensive examination of AI models for detecting Down syndrome (DS) using methods such as blood tests, ultrasound imaging, facial analysis, and foot deformities. Analyzing research from 2017 to 2024, it highlights recent advancements, challenges, and future directions. Convolutional neural networks (CNNs), a form of deep learning, show promise in accurately identifying DS based on visual features, with transfer learning addressing limited datasets and overfitting. 22 Ultrasound imaging can detect DS markers like nasal bone (NB) length and nuchal translucency (NT) during pregnancy, aided by machine learning integration for streamlined analysis. Foot abnormalities, including the "sandal gap," offer additional diagnostic insights into DS, though further research is needed to understand deformities across age groups. Blood tests like the triple test screen for chromosomal abnormalities in pregnant women, with machine learning, especially multilayer perceptron (MLP) networks, enhancing prenatal care by analyzing biomarkers and predicting individual risk. In conclusion, AI combined with diagnostic modalities improves DS detection, benefiting individuals and families, with ongoing research essential for addressing ethical concerns and ensuring fair AI use across diverse populations. 23 CHAPTER-7 PROJECT TIMELINE 7.1 WORK BREAKDOWN & GANTT CHART 7.2 PROJECT TIMELINE The timeline is divided into several key milestones, beginning with the initial research and dataset collection phase, followed by model development and validation. Subsequent phases include optimization for edge devices, interface design, and extensive testing. Each phase is meticulously planned to ensure that dependencies are managed, and project goals are met within the stipulated timeframe. Gantt charts for individual team members highlight specific tasks and deadlines, ensuring accountability and facilitating efficient project management. 7.3 INDIVIDUAL GANTT CHART Anirudh’s Gantt Chart (Regn. No.:102165013) 24 Abhiyudhya’s Gantt Chart (Regn. 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