This paper presents a novel approach for glaucoma diagnosis using a lightweight convolutional neural network (CNN) architecture optimized for efficiency and accuracy. The model, designed to run effectively on resource-constrained devices, leverages depthwise separable convolutions and advanced image preprocessing to detect glaucomatous features in fundus images. Evaluated on benchmark datasets, the proposed method demonstrates high diagnostic accuracy and computational efficiency, indicating its potential for integration into real-time, accessible glaucoma screening tools, especially in underserved regions.
Introduction
Glaucoma is a progressive, irreversible eye disease and the second leading cause of vision loss worldwide, expected to affect over 111 million people by 2040. Early detection is crucial due to its asymptomatic onset. This study presents a soft computing-based system, called the Discriminator Model for Glaucoma Diagnosis (DMGD), which automates glaucoma detection from fundus images using advanced image preprocessing, feature extraction, and Support Vector Machine (SVM) classification.
Key Components of the Study
1. Problem Statement
Manual retinal image analysis is time-consuming, subjective, and often inconsistent.
Variability in image quality and anatomical complexity challenges accurate and scalable diagnosis.
There is a need for automated, accurate, and robust diagnostic systems to aid early detection.
2. Objectives
Improve diagnostic accuracy for glaucoma.
Support ophthalmologists in clinical decision-making.
Handle data variability and enhance scalability of retinal screening.
3. Methodology
The DMGD framework operates in three main stages:
A. Preprocessing
Enhances image quality and isolates the optic disc (OD).
Steps include:
Color channel separation and cropping (green channel highlights OD).
SWFCM clustering for OD segmentation.
Gaussian Derivative Filters for vessel detection.
Inpainting algorithms to remove vessels and clean the region of interest.
B. Feature Extraction
Extracts color-based statistics (mean, standard deviation, skewness, kurtosis).
Uses Local Binary Patterns (LBP) and LAWS texture features to capture spatial and frequency-based textures.
C. Classification
Applies SVM with four kernel functions: Linear (LK), Polynomial (PK), Quadratic (QK), and Radial Basis Function (RBF).
The RBF-SVM achieved the best performance in distinguishing between glaucomatous and normal cases.
4. Results and Evaluation
Databases used: HRF, DRISHTI-GS1, RIM-ONE, ORIGA.
Evaluation via 10-fold cross-validation.
A. Best Performance: RBF-SVM
Accuracy: Up to 98.47% (RIM-ONE), 97.03% (DRISHTI-GS1).
Specificity: 100% (HRF dataset).
Sensitivity: 93.33%.
Outperformed other kernels, especially PK-SVM, which had <75% accuracy.
B. ROC and Confusion Matrix
ROC curves confirmed RBF-SVM’s superior classification ability (high AUC).
Confusion matrices showed strong precision and balance in predictions.
Conclusion
This study introduces a soft computing-based Discriminator Model for Glaucoma Diagnosis (DMGD) that effectively combines advanced image preprocessing, multi-domain feature extraction, and kernel-based SVM classification. By accurately segmenting the region of interest and removing irrelevant structures, the system enhances the reliability of glaucoma detection. Among various kernel classifiers tested, the RBF-SVM consistently demonstrated the highest accuracy across multiple fundus image datasets. The results indicate that the DMGD system offers a promising tool for supporting clinical diagnosis and could serve as a reliable second opinion in glaucoma screening.
References
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