Astigmatism (散光)

In astigmatism, the eye is not a perfect sphere (like a football) but develops in a more oval or irregular shape (like a rugby ball). The uneven surface of the eye causes focusing of light rays onto different points within the eye, resulting in blurred images or multiple images.

Vision in all distances may be blurred, and correction with glasses or contact lenses will be needed to improve vision. LASIK can also be done to rectify this “power error”.

Astigmatism (together with presbyopia, myopia or hyperopia) can be corrected by modern cataract surgery in which the cataractous lens is replaced by advanced technology lens implants.