Retinitis pigmentosa (RP) is a human disease characterized by loss of photoreceptor cells, especially rods, leading to visual disturbance and eventually blindness. Effective treatments for controlling RP remain unavailable. Infectious keratitis is a visual threatening eye condition of the cornea that can cause severe visual loss if not appropriately managed in a timely manner. Only 50% of the eyes will enjoy good visual recovery if antibiotic treatment is delayed. Causative pathogens include bacteria, virus, fungus, protozoa and parasites. A number of risk factors have been identified for microbial keratitis, including contact lens wear, recent ocular surgery or ocular trauma, ocular surface disease, dry eyes, eyelid deformities, corneal sensation impairment, chronic use of topical steroids and immunocompromised states. This book discusses the prevalence, symptoms and treatment options of eye disorders.