Examples of refractive error are myopia, hyperopia, presbyopia and astigmatism. Other types of refractive error are hyperopia, astigmatism, and presbyopia. Types of ametropia include myopia, hyperopia and astigmatism. Premium intraocular lenses are those used in correcting presbyopia or astigmatism. It is a type of refractive error along with nearsightedness, farsightedness, and astigmatism. Refractive errors include near-sightedness, far-sightedness, presbyopia, and astigmatism. This may result in blurry vision, double vision, nearsightedness, astigmatism, and light sensitivity. This was mainly due to opacities in both corneas, complicated by hyperopia and astigmatism. The most common use is to treat refractive errors&colon; myopia, hypermetropia, astigmatism, and presbyopia. Defective vision occurs due to marked corneal astigmatism. Sheep eyes exhibit very low hyperopia and little astigmatism. Other optical causes are astigmatism or more complex corneal irregularities. This means that a spherical rigid contact lens can correct corneal astigmatism. Spherical lenses are adequate correction when a person has no astigmatism. Toric IOLs may be used during the CLEAR procedure to correct astigmatism.