#astigmia__astigmatism  (ophthalmology) impaired eyesight resulting usually from irregular conformation of the cornea
  supertype:  ametropia  (ophthalmology) faulty refraction of light rays in the eye as in astigmatism or myopia
  subtype:  keratectasia  abnormal bulging of the cornea of the eye
  subtype:  keratoconus__keratoconu  abnormal cone-shaped protrusion of the cornea of the eye; can be treated by epikeratophakia

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