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Artificial Intelligence in Health                             Segmentation and classification of DR using CNN



            images and applying decision trees, Naive Bayes, or k-NN,    A             B
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            yielded an accuracy of 73.4% and an F-measure of 68.4%
            on a dataset of 151 images with varying resolutions. These
            efforts  illustrate  ongoing  advancements  in  leveraging
            machine learning for DR detection.
              The  rise  of  deep  learning  approaches  has  led  to  the
            development of various methods for applying CNNs for
            DR detection. Pratt et al.  developed a network with a CNN   Figure 1. The original fundus image and its corresponding mask from
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                                                               the IDRiD. This dataset, consisting of 516 images, captures lesion
            architecture and data augmentation capable of identifying   segmentation in fundus images taken by a retinal specialist in Nanded,
            intricate features related to classification tasks such as   Maharashtra, India.  (A) Original fundus image and (B) the corresponding
            MAs, exudates, and hemorrhages (HEs) in the retina,   mask. Images obtained from the IDRiD.
            providing automated diagnoses without user input. Their   Abbreviation: IDRiD: Indian diabetic retinopathy image dataset.
            model  achieved  a  sensitivity  of  95%  and  an  accuracy  of
            75% on a validation set of 5000 images. Other researchers   macula, and a resolution of 4288 × 2848 pixels stored in
            have also contributed to CNN-based approaches.     jpg file format, with each image approximately 800 KB in
                                                        9,10
            Notably, Asiri et al.  conducted a comprehensive review   size. 15
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            of existing methods and datasets, highlighting their pros   For assessing lesion segmentation techniques related to
            and cons while emphasizing the challenges in designing   DR, pixel-level annotated data includes binary masks for
            efficient and robust deep learning algorithms for diverse   distinct abnormalities, including MAs, hard exudates (EXs),
            problems in DR diagnosis and suggesting directions for   HEs, and soft exudates (SEs). The dataset comprises color
            future research.                                   fundus images in.jpg format, along with corresponding
              Moreover, researchers have explored transfer learning   binary masks in.tiff files. The dataset contains 81 images
            using CNN architectures. Hagos and Kant  attempted to   with binary masks for MAs, 81 for EXs, 80 for HEs, and 40
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            train InceptionNetV3 for 5-class classification with pre-  for SEs, accommodating images with multiple lesions and
            training on the ImageNet dataset, achieving an accuracy   enhancing robust research and performance evaluation of
            of 90.9%. Sarki et al.  trained ResNet50, Xception Nets,   lesion segmentation techniques in DR. 36
                             13
            DenseNets, and VGG with ImageNet pre-training,
            obtaining the best accuracy of 81.3%. Both research teams   1.2.3. Image grading
            utilized datasets provided by APTOS and Kaggle.    Our  research  utilized  image  data  sourced  from  multiple
                                                               datasets, primarily focusing on an open dataset obtained
            1.2. Problem statement
                                                               from the Kaggle DR Detection Challenge 2015  for pre-
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            1.2.1. Datasets                                    training CNNs.  This dataset is widely recognized as
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            The image data employed in this study was obtained from   the largest publicly available, comprising 35,126 fundus
            diverse datasets. The research encompasses three primary   photographs capturing both the left and right eyes of
            objectives: lesion segmentation, disease/image grading,   American citizens. The images are labeled with stages of
            and treatment recommendations.                     DR, ranging from no DR (label 0) to proliferative DR (label
                                                               4), as illustrated in Figure 2. 18
            1.2.2. Lesion segmentation                           In  addition  to  the  Kaggle  dataset,  we  incorporated
            Lesion segmentation in the Indian Diabetic Retinopathy   other smaller datasets, including the IDRiD,  as shown in
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            Image Dataset (IDRiD) uses fundus images captured by a   Figure 3, from which we utilized 413 fundus photographs,
            retinal specialist at an eye clinic in Nanded, Maharashtra,   and the methods to evaluate segmentation and indexing
            India. From the 100 of examinations available, we have   techniques in the field of retinal ophthalmology
            extracted 516 images to form our dataset, as shown in   (MESSIDOR)  dataset, contributing 1200 fundus
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            Figure 1A and B. 12                                photographs. To ensure consistency, we used a version of
                                                               the MESSIDOR dataset that had been relabeled to standard
              Experts verified that all images are of adequate quality                        21
            and clinically relevant, that no image is duplicated, and that a   grading by a panel of ophthalmologists.
            reasonable mixture of disease stratifications representative   Evaluation of our models was conducted on the Kaggle
            of DR and diabetic macular edema is present.  The fundus   APTOS 2019 Blindness Detection  dataset, with access
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            images were acquired using a Kowa VX-10 alpha digital   limited to the training portion. The full APTOS 2019
            fundus camera with a 50° field of view, centered near the   dataset comprises 18,590 fundus photographs divided into

            Volume 1 Issue 4 (2024)                         32                               doi:10.36922/aih.2783
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