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Updated: Feb 26, 2026

Three Different Protocols of Corneal Collagen Crosslinking in Keratoconus: Conventional, Accelerated and Iontophoresis

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Interrelationships Between 3 Keratoconic Cone Parameters.

Kyaw L Tu¹, Abdo K Tourkmani, Singaram Srinivas

¹Stanley Eye Unit, Abergele Hospital, Abergele, Wales, United Kingdom.

|July 14, 2017

Summary

This summary is machine-generated.

Keratoconic cone parameters show significant relationships. Thinner cones are more central but steeper, indicating less decentration with increased steepness.

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Area of Science:

Ophthalmology
Corneal topography
Keratoconus research

Background:

Keratoconus is a progressive thinning of the cornea.
Understanding keratoconic cone parameters is crucial for diagnosis and management.
Key parameters include maximum keratometry (Kmax), thinnest point pachymetry (T), and decentration (D).

Purpose of the Study:

To investigate the interrelationships between Kmax, thinnest point pachymetry, and decentration in keratoconus.
To determine how these three keratoconic cone parameters correlate with each other.

Main Methods:

Retrospective analysis of 101 keratoconic eyes from 58 patients.
Corneal topography data (Kmax, T) obtained using Pentacam.
Decentration (D) calculated using trigonometry.
Pearson correlation coefficients computed for T-D, T-K, and D-K relationships.

Main Results:

Statistically significant positive correlation between thinnest point pachymetry (T) and decentration (D) (R = 0.366, P = 0.0002).
Statistically significant negative correlation between thinnest point pachymetry (T) and Kmax (K) (R = -0.719, P < 0.00001).
Statistically significant negative correlation between decentration (D) and Kmax (K) (R = -0.281, P = 0.0044).

Conclusions:

Keratoconic cones exhibit complex interrelationships between pachymetry, decentration, and steepness.
Thinner cones tend to be more centrally located (less decentration).
Thinner and more central cones are associated with greater corneal steepening (higher Kmax).