Detection of Optic Disc using Level Set Algorithm

Abstract
Glaucoma is an eye disease which damages the optic nerve in the eye. It is the world second leading disease which causes blindness. It can be diagnosed through measurement of optic disc area. Fluid pressure within the eye rises which damages the optic nerve in the eye. Automatic calculation of optic disc boundary is challenging due to the interweavement of blood vessels with surrounding tissues around the disc. A variable level set algorithm of optic disc ellipse optimization improves the accuracy of boundary. The algorithm used is demonstrated on various data sets collected from Aravind Eye hospital from Pondicherry. The area of the optic disc obtained is better than the results of other data sets. This further leads to a large clinical evaluation of the algorithm involving various data sets.
I.Introduction
Glaucoma is one of the common causes of blindness. It causes progressive degeneration of optic nerve fibers and leads to structural changes of the optic nerve head and a simultaneous functional failure of the visual field. Since, glaucoma cannot be cured at final stage and leads to vision loss and cannot be restored, therefore its early detection and subsequent medical treatment is essential to prevent visual damage. Glaucoma is a condition that involves distinctive changes in the optic nerve and visual field. Optic nerve damage in the eye can ordinarily be alleviated and inhibited by sufficiently reducing intraocular pressure (IOP).Glaucoma is a disease of the major nerve of vision, called the optic nerve. The optic nerve receives lightgenerated nerve impulses from the retina and transmits to the brain, where we recognize these electrical signals as vision. If glaucoma is not diagnosed and treated, it leads to loss of vision. Glaucoma is the leading cause of blindness worldwide. In fact, as many as 6 million individuals are blind in both eyes from this disease. A watery material called aqueous humor is present in the eye. The aqueous humor is produced by the ciliary body and is drained through the Canal of Schlemm. If the aqueous humor does not drain out correctly, then pressure will build up in the eye. 3 million people in the United States have been affected by Glaucoma. Half of the people living do not know as such they are affected by the disease. The reason why people are unaware is, they do not know any symptoms and finally results in
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