Keratoconus Phenotypes based on Corneal Topography, Tomography, and Aberrometry: A Morphological-surgical Classification
Year: 2025
Type: article
Abstract: IntroductIonThe successful keratoconus treatment through intrastromal corneal ring segments (ICRS) implantation is founded on two pillars: Firstly, to classify the keratoconus morphology by assessing the information obtained by corneal topography, tomography, and aberrometry; secondly, to reshaping corneal morphology through a customized ICRS implantation strategy.[1][2][3][4][5][6][7][8][9][10][11] Consequently, for a successful keratoconus treatment with ICRS, the first step is to characterize and classify the keratoconus' morphology.The classical morphological classifications, pioneered by Rabinowitz, coexist with the evolutive classifications. [12][13]3][14][15][16][17][18][19][20] However, it is worth noting that each classification's main aim is different.While morphological classifications focus on describing the keratoconus shape, the evolutive classification aims to stage the keratoconus at the diagnosis moment and evaluate the disease progression.From a therapeutic perspective, the morphological classifications are helpful for the treatment approaches that aim to reshape corneal morphology.In contrast, the evolutive classifications are useful to evaluate the efficacy of the treatments aiming to halt the disease progression.This article presents a morphological classification based on corneal topography, tomography, and aberrometry parameters with the aim of establishing customized treatment strategies focused on reshaping corneal morphology and improving the visual quality of the patients with keratoconus. Background o f MorphologIcal patterns o f keratoconus Morphological Patterns based on Topographic Curvature MapsIn the 1990s, the development of topographic devices based on the analysis of Placido's disk represented a significant advance in assessing the cornea.Rabinowitz pioneered this field, describing different topographic patterns using curvature maps in healthy and pathological corneas.12,13 Later, the contributions of other authors made it possible to define several patterns, which could be summarized as follows (Fig. 1).• Bow tie with symmetrical lobes not skewed to each other: This pattern is like congenital astigmatism.However, the central cornea is thinner than healthy corneas.• Bow tie with symmetrical lobes and skewed to each other: This pattern represents the typical "crab claw" picture on corneal topography.• Bow tie with asymmetrical lobes not skewed to each other: This pattern has an inferior-superior asymmetry.However, there is no deviation in the axes of each hemi-meridian.• Bow tie with asymmetrical lobes skewed to each other: This pattern has an inferior-superior asymmetry.There also is a deviation of the axes of each hemi-meridian.• The mixed pattern is a combination of the previous patterns.
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4409697914