[Quantitative topographic detection of keratoconus in the contralateral eye in clinically unilateral keratoconus. Apropos of 5 cases].

BACKGROUND: Keratoconus is generally bilateral and follows an asymmetrical course. The goal of this study was to evaluate efficiency of the automated topographic screening indices on early keratoconus by examination of the fellow eyes of clinically unilateral keratoconus. PATIENTS AND METHOD: We examined the fellow eyes of 5 cases of clinically unilateral keratoconus by videokeratography using TMS-1 Computed Anatomy device, which incorporates the keratoconus screening indices from Rabinowitz (K and I-S values) and Klyce/Maeda (KPI value and other quantitative induces as OSI, DSI and CSI). RESULTS: One case (number 1) had keratoconus detected by both Rabinowitz and Klyce/Maeda indices. Two cases (number 2 and 3) had normal keratoconus screening indices. Two cases (number 4 and 5) had keratoconus detected by Rabinowitz I-S value, with a 0% KPI value. CONCLUSIONS: Rabinowitz indices are sensitive with a poor specificity. The Klyce/Maeda indices are less sensitive but more specific. Both methods may be useful for keratoconus detection. The results must always be analysed in relation to a clinical observation of both eyes and the course of the topographic changes.