Primary objective of this study was evaluate the diagnostic capacity of fourier analysis of keratometric data in differentiating moderate KC and FFK from healthy corneas.

Study participants were recruited from the Cornea Outpatient service in a consecutive if eligible basis. Two study groups were formed: a)KC group included patients those were diagnosed and classified for moderate keratoconus according to the Amsler-Krumeich classification system, b) FFK group (FFKG) that included patients diagnosed with FFK, and c) Control group (CG) was formed by refractive surgery candidates. Pentacam (Pentacam HR, Oculus Optikgerate GmbH, Heidelberg, Germany)measurements were performed by the same experienced operator in a consistent way.

Inclusion Criteria:

• diagnosis of keratoconus KC in the fellow eye according to the Amsler-Krumleich criteria (FFKG)
• KISA index between 60 and 100% in the FFK eye (FFKG)
• lack of any KC-related findings / signs in the slit-lamp biomicroscopy (FFKG)
• uneventful ophthalmologic history (CG)
• no indications of corneal pathology in slit-lamp biomicroscopy and Placido *disk-based videokeratography (CG)
• KISA index value less than 60% (CG)
• diagnosed and classified for moderate keratoconus according to the Amsler-Krumeich classification system (KCG)

Exclusion Criteria:

• for all study groups:

  • previous incisional eye surgery
  • corneal scars and opacities
  • history of herpetic keratitis, severe eye dryness
  • pregnancy or nursing
  • current corneal infection
  • glaucoma
  • suspicion for glaucoma
  • IOP lowering treatment
  • underlying autoimmune disease

All participants were recruited from the Outpatients Cornea service, in a consecutive if eligible basis