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Artificial Intelligence in Health                             Segmentation and classification of DR using CNN



            images  and their corresponding  ground  truth  masks.   Table 1. Segmentation results
            Utilizing the U-Net model previously trained on augmented
            data, the model’s predictive capabilities are scrutinized for   Segmentation   Metric(s)  Performance
                                                               method
            pixel-level segmentation accuracy. The model’s state is
            restored  using  the  best-performing  checkpoint  achieved   UNet  Dice coefficient; IoU  0.95 dice; 0.92 IoU
            during the training phase, ensuring the evaluation is based   DeepLab  Dice coefficient; IoU  0.80 mIoU
            on the most optimized configuration.               FCN         Pixel accuracy; IoU  0.92-pixel accuracy; 0.70 IoU
                                                               SegNet      Pixel accuracy; IoU  0.88-pixel accuracy; 0.65 IoU
              For each test sample, the retinal fundus image is pre-
            processed by normalizing pixel values and transposing the   PSPNet  Mean intersection   0.78 mIoU
                                                                           over union (mIoU)
            channels to match the model’s input requirements. Similarly,
            the ground truth mask undergoes pre-processing to   LinkNet    Pixel accuracy; IoU  0.85-pixel accuracy; 0.68 IoU
            facilitate direct comparison with the model predictions. The   Mask R-CNN  AP  0.65 AP
            evaluation metrics, including Jaccard index, F1 Score, recall,   Abbreviations: IoU: Intersection over union; mIoU: Mean intersection
            precision, and accuracy, are computed for each test image.   over union; AP: Average precision; FCN: Fully Convolutional Network.
            These  metrics  quantify  the  model’s  ability  to  accurately
            delineate DR-related regions in the retinal fundus images. 35  Table 2. Performance metrics for lesion segmentation in the
                                                               Indian diabetic retinopathy image dataset
              The computational efficiency of the model is also
            assessed through the calculation of frames per second   Different   Jaccard  F1 score Recall  Precision Accuracy
            (FPS) during the inference process. This metric provides   segmentations  score  score
            insights into the real-time processing capabilities of   Blood vessel  0.6634  0.7974  0.7771  0.8240  0.9922
            the model, offering valuable information for potential   Hard exudate  0.6663  0.7953  0.7634  0.8252  0.9986
            deployment in clinical or real-world scenarios. Visual   Soft exudate  0.6679  0.7874  0.7738  0.8340  0.9981
            representations of the model’s predictions, alongside the   Hemorrhage  0.6551  0.7874  0.7852  0.8161  0.9958
            original retinal fundus images and ground truth masks, are   Microaneurysms  0.6761  0.8061  0.7731  0.8279  0.9967
            saved for qualitative analysis and comparison.     Optical disc  0.6638  0.7956  0.7671  0.8238  0.9989

            3. Results
            3.1. Segmentation results                          Notably, the model demonstrated efficient segmentation
                                                               with an average accuracy of 0.9986 and an impressive
            UNet achieved the highest performance with a dice   FPS rate of 361.188719052. Visual results were generated
            coefficient of 0.95 and an intersection over union (IoU)   for each test image, illustrating the original image, the
            of 0.92. Following closely, fully convolutional network   ground truth mask, and the predicted segmentation
            exhibited a pixel accuracy of 0.92 and an IoU of 0.70.   mask. Overall, these findings highlight the effectiveness
            DeepLab attained a mean IoU (mIoU) of 0.80, while   and computational efficiency of the proposed blood
            SegNet and LinkNet demonstrated pixel accuracies of 0.88   vessel segmentation model, showcasing its potential for
            and 0.85, respectively, with IoUs of 0.65 and 0.68. PSPNet   applications in DR diagnosis and treatment planning, as
            yielded a mIoU of 0.78. Finally, Mask R-CNN, evaluated   visualized in Figure 6.
            by  average  precision,  achieved  a  performance  of  0.65.   In this research, we conducted a comprehensive
            These results provided insights into the efficacy of different   evaluation of a segmentation model across various retinal
            segmentation methods, highlighting UNet as a particularly                        15    14
            promising approach for accurate image segmentation tasks   structures, including blood vessels,  EXs,  SEs, HEs,
                                                               MAs, and the optical disc.  The model’s performance was
                                                                                    37
            in Tables 1 and 2.
                                                               quantitatively assessed using key metrics, revealing high
              In this study, we employed a U-Net-based model   segmentation accuracy  across all  structures. The  Jaccard
            for the segmentation of blood vessels in retinal images.   scores ranged from 0.6551 to 0.6761, indicating substantial
            The implemented model was evaluated on a test dataset   overlap between the predicted and ground truth masks.
            comprising retinal images and corresponding ground   The model  achieved notable F1  scores,  demonstrating
            truth masks. The testing process involved loading images   a harmonious balance between precision and recall,
            and masks, pre-processing the data, and utilizing a   ranging from 0.7874 to 0.8061. Particularly, commendable
            pre-trained U-Net model for predictions. The model’s   was the recall scores, signifying the model’s ability to
            performance was assessed using several metrics, including   correctly identify relevant instances, with values ranging
            Jaccard similarity, F1 score, recall, precision, and accuracy.   from 0.7634 to 0.7852. Precision scores, representing the


            Volume 1 Issue 4 (2024)                         37                               doi:10.36922/aih.2783
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