Automatic detection of blood vessels and evaluation of retinal disorder from color fundus images

摘要

Here, an unique approach is presented for automatic detection of blood vessels and estimation of retinal disorder from color fundus image. This technique can be used to determine the progression of retinal disorders due to diabetic retinopathy, which can help in better evaluation and treatment for clinical purposes. The proposed method combines the Gaussian based matched filter with Kirsch for extraction of blood vessels, and inpainting technique to determine the pathologically affected region. This is tested on various databases (such as: DRIVE, Aria and Glaucoma etc.,). Various performance measures (such as: accuracy, sensitivity, specificity and F-score etc.,) are used to estimate the quality of blood vessels detection. Here, we have applied the segmentation technique to the subband-2 image in 5-level wavelet decomposition by db4 mother wavelet. This reduces the computational time for inpainting. Comparing the blood vessels and the pathologies, index for blood vessel damage is calculated. This index is proportional to retinal damage in case of diabetic retinopathy. Higher index corresponds to significant amount of blood vessel damage. From the index, progression of the disease and condition of the retina can be assessed. The index for blood vessel damage for Im-24 is 2.98%, whereas for Im-18 is 68.78%. This indicates that in Im-18 more blood vessels are affected by pathologies. It also indicates that maximum portion of the retina is affected by pathology.