Cinemakeratography using computer morphing.

Abstract

PURPOSE: TMS-1 videokeratography (Tomey Technologies, Inc.) was animated using computer morphing to visualize corneal shape change over time. METHODS: Morphing was performed using keratoconus (8 examinations/76 months) and postoperative photorefractive keratectomy (PRK) corneas (8 examinations/37 months; LSU PRK Phase IIa). RESULTS: In the keratoconus animation, the inferior cone increased curvature, but not equally in all directions, nor at a constant rate. The cone apex did not drift over time. Periodic flattening and steepening was observed superiorly, as well as cone regression at month 76. The Keratoconus Prediction Index (KPI) at month 0 was 0.18, plateaued at 0.36 at month 46, and dropped to 0.33 at month 76. In the post-PRK animation there was continuous corneal remodeling out to 30 months. Fluctuating steep and flat regions of the ablation zone correlated with the Surface Regularity Index (SRI). CONCLUSION: Cinemakeratography (Cinema-K) enhanced our appreciation of subtle changes in corneal topography.