Retinopathy of Prematurity Vessel and Ridge Parameters Measurement by Unsupervised Algorithm

Abstract

The Retinopathy of Prematurity (ROP) is an ocular pathological disorder of the retinal blood vessels in premature infants and low birth weight infants. It is essential that those caring for premature infants should know who is at risk of ROP and their severity stage. It is also important that when screening must begin and how often these infants need to be examined otherwise the progression lead most severe stage and can cause blindness. The contrast stretching method has been utilized to enhance the ROP color image. Then an automatic method Isotropic Un-decimated Wavelet Transform (IUWT) has been proposed to extract the abnormal retinal blood vessel and measure its width and tortuosity. The ridge formation of this pathological disorder has also been obtained by the IUWT. The quantitative measurements of mean diameter, standard deviation, tortuosity, length of retinal blood vessel and ridge have been considered and computed the exact severity stage of ROP. The effectiveness of the proposed method has been verified through machine vision techniques and the results obtained are encouraged by experts. Automatic ROP screening system comprises several advantages, like a substantial time reduction of ophthalmologists in diagnosis, a non ophthalmologist can provide stage of ROP, improving the sensitivity of the test and a better accuracy in diagnosis.