Rizzuti's sign in advanced keratoconus

A 24-year-old male presented with progressive, painless visual decline in the right eye, with a best-corrected visual acuity of 20/80. Slit-lamp photographs obtained with temporal illumination demonstrated a sharply demarcated conical light reflex on the nasal corneal surface (Figure 1A, B), consistent with Rizzuti's sign⁽¹⁾. Anterior segment optical coherence tomography (Figure 1C) revealed apical corneal thinning, with a minimum corneal thickness of 422 μm. Rizzuti's sign results from localized corneal steepening that focuses incident light onto the opposite limbal region and is a classic clinical sign of advanced keratoconus.

REFERENCE

1. Rabinowitz YS. Keratoconus. Surv Ophthalmol. 1998;42(4):297-319.

Submitted for publication: May 27, 2026.
Accepted for publication: June 23, 2026.

Data Availability Statement: The datasets generated and/or analyzed during the current study are included in the manuscript.

Edited by
Editor-in-Chief: Newton Kara-Júnior
Associate Editor: Carlos Augusto Moreira Neto

Funding: This study received no specific financial support.

Disclosure of potential conflicts of interest: The authors declare no potential conflicts of interest.