Abstract
Purpose: :
To investigate whether and how often keratoconus suspected cases progress to true keratoconus. Suspected keratoconus is defined as cases with suspicious findings by videokeratography examinations but having no clinical findings (Fleischer's ring or Vogt's striae) by slit–lamp biomicroscopy.
Methods: :
Subjects were 34 eyes of 34 patients of keratoconus suspect. The eyes had no clinical findings of keratoconus such as Fleischer's ring and Vogt's striae by slit–lamp biomicroscopy, had best spectacle–corrected visual acuity of 20/20 or better, showed keratoconus suspected pattern with videokeratography, and their contralateral eyes were diagnosed as keratoconus. They were followed up for at least 3 years, and best corrected visual acuity, slit–lamp biomicroscopy and videokeratography examinations were repeated. Their age ranged between 13 and 40 (24.1 ± 7.5, mean ± SD) years old. The average follow–up period was 6.0 ± 2.2 years.
Results: :
During the follow up period, 5 eyes (14.7%) showed apparent progression from suspected keratoconus to true keratoconus. On average, apparent clinical symptoms by slit–lamp biomicroscopy developed in 5.2 years. Kaplan–Meier analysis revealed that cumulative incidence of progression to true keratoconus was 21.5 % in 6 years.
Conclusions: :
Our findings suggest that progression of suspected keratoconus to true keratoconus is not rare. This fact should be taken into account in determining indication of corneal refractive surgery.
Keywords: keratoconus • topography • refractive surgery: corneal topography