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Cambios tomográficos de Scheimpflug en el espectro del queratocono según la clasificación modificada de

Seher Köksaldı¹, Mustafa Kayabaşı², Ezgi Karataş¹

¹Department of Ophthalmology, Faculty of Medicine, Agri Ibrahim Cecen University, Firat Neighborhood, Yeni Universite Street, No: 2, 04100, Agri, Turkey.

European journal of medical research

|February 6, 2026

Abstracto

Purpose:

To characterize spectrum-dependent changes in Scheimpflug tomographic parameters across normal, keratoconus suspect, and eyes with keratoconus classified using the modified Rabinowitz-McDonnell index.

Methods:

This retrospective comparative study included 115 eyes of 115 patients evaluated at a tertiary ophthalmology clinic. Based on the modified Rabinowitz-McDonnell index, eyes were categorized into control (n = 37), keratoconus suspect (n = 51), and keratoconus (n = 27) groups. All eyes underwent Scheimpflug tomography. Anterior and posterior keratometry values, corneal thickness parameters, corneal volume, anterior chamber depth, and pupil diameter were analyzed.

Results:

Anterior and posterior corneal curvature parameters increased progressively from control group to keratoconus suspect group and were highest in eyes with keratoconus (all p < 0.001). While anterior keratometric parameters and posterior corneal curvature differed significantly between control and keratoconus suspect groups, pachymetric measurements remained comparable, with significant thinning observed only in the keratoconus group (all p < 0.001). Corneal volume was higher in keratoconus suspect group compared with both control and keratoconus groups (p = 0.001). Anterior chamber depth was greater in keratoconus group, while pupil diameter was smaller in keratoconus suspect group (both p < 0.01).

Conclusion:

When keratoconus is classified using central keratometry, Scheimpflug tomography demonstrates a clear, stage-dependent pattern of corneal change. Curvature-related alterations precede measurable thinning, highlighting that curvature-based classification remains clinically relevant and that tomographic parameters can enhance disease characterization across the keratoconus spectrum.

Palabras clave:

Queratocono Sospecha de queratocono Criterios modificados de Rabinowitz-McDonnell Pentacam Tomografía de Scheimpflug

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