title: Keratoconus.
abstract: Keratoconus is characterized by the presence of corneal distortion (secondary to thinning of the apex) and either Fleischer's ring (found in 57% of patients) or Vogt's striae (found in 44% of patients). Often the only presenting symptom is decreased visual acuity. Steep keratometric readings are not usually diagnostic; 18% of patients with keratoconus have readings flatter than 45.00 D. Treatment requires correction of acuity with spectacles or contact lenses. More advanced cases are generally managed with rigid gas-permeable contact lenses. Corneal scarring occurs in approximately 43% of cases; 10% to 20% of patients require penetrating keratoplasty to restore acuity.
authors.affiliation: Southern California College of Optometry, Fullerton, USA.
authors.forename: T B
authors.initials: TB
authors.lastname: Edrington
authors.forename: K
authors.initials: K
authors.lastname: Zadnik
authors.forename: J T
authors.initials: JT
authors.lastname: Barr
mesh_terms: D003261:Contact Lenses; D003315:Cornea / Q000473:pathology*; D003937:Diagnosis, Differential; D005139:Eyeglasses; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy; D015948:Keratoplasty, Penetrating; D011379:Prognosis; D014786:Vision Disorders / Q000175:diagnosis; D014792:Visual Acuity