SUMMARY
To determine the topographic patterns of keratoconus, computer-assisted topographic evaluations were performed on 59 corneas of unoperated eyes of 34 patients with keratoconus. Each patient had slit-lamp findings consistent with the diagnosis of keratoconus in at least one eye or had been submitted to keratoplasty for keratoconus in the fellow eye. Twenty-five patients had topographic maps obtained for both eyes and nine patients in only one eye because of penetrating keratoplasty in the opposite eye. Patterns included symmetric bow-tie (2/57; 3,51%); asymmetric bow-tie (13/57; 22,81%); distorted bow-tie (15/57; 26,32%); peripheral (17/57; 29,82%); central (1/57; 1,75%) and irregular (9/57; 15,79%). Two eyes of two patients with keratoconus in the fellow eye had patterns similar to those observed in against rule astigmatism, but not typical of keratoconus and, therefore, were not included in the casuistic.
Comparing the topographic patterns of each eye in one patient and of different patients in different stages of the disease, the authors propose a possible evolutive route for the development of keratoconus.