Long Term Tomographic Changes In Visually Stable Keratoconus Patients In A Tertiary Hospital In Spain
Published 2024 - 42nd Congress of the ESCRS
Reference: PO820 | Type: Poster | DOI: 10.82333/mgap-az24
Authors: Laura Prieto Dominguez 1 , Sebastián Martínez Tapia* 1 , Ignacio López Miñarro 1 , Isabel Bermejo Rodríguez 1 , María Gómez Tomás 1 , David Galarreta Mira 2
1Ophthalmology,Hospital Clínico Universitario de Valladolid,Valladolid,Spain, 2Ophthalmology,Hospital Clínico Universitario de Valladolid,Valladolid,Spain;Ophthalmology,Instituto Oftalmológico Recoletas,Valladolid,Spain
Purpose
The objective of this study is to examine the long-term progression of some tomographic corneal parameters of significant relevance in the context of refractive and visually stable keratoconus, specifically focusing on anterior curvature, refractive power, corneal volume and total corneal power. This investigation spans a ten-year follow-up period. Such insights are paramount in enhancing our understanding of the natural course of keratoconus and may offer invaluable guidance for optimizing patient management strategies and treatment interventions.
Setting
The study was conducted in a specialized ocular surface reference unit within a tertiary hospital in Spain. Data obtained with the Galilei G6 (Ziemer PORT, Switzerland) from patients undergoing follow-up for keratoconus for at least 10 years were analyzed, regardless of their age or gender.
Methods
Tomographical data from patients in the ocular surface unit, with a minimum 10-year follow-up, stable refractive and visual acuity (≤ 1D change and ≤ 1 line Snellen chart lost), and no surgeries, were collected using Galilei G6 software version 6.0.3. Descriptive analysis of variables including anterior instantaneous curvature (AIC Q and mean K in diopters (D)), refractive power (RP mean K in D), corneal volume (CV in mm3) and total corneal power (TCP in D) was conducted using Microsoft Excel. Comparisons were made between the parameters from measurements taken at baseline, 5 years, and 10 years of follow-up for each eye using Friedman test (X2). The analysis was performed using the statistical software SPSS (IBM, version 29.0).
Results
Forty-six patients were included, 92 eyes, female/male 19/27. Age at onset was 35,6±14,2 years. Main results at baseline, 5 and 10 years were:
AIC e2(-Q): OD (1,2±1,3, 1,0±1,3 and 0,6±0,6) OI (1,0±0,8, 0,8±0,7 and 0,6±0,6). X2: OD 17,7, OI 16,6 (p<0,001).
AIC mean K (D): OD (45,0±3,1, 46,3±3,0 and 46,7±3,4), OI (45,7±2,8, 46,1±3,2 and 46,5±3,4). X2: OD 40,3, OI 33,4 (p<0,001).
CV (mm3): OD (29,4±2,0, 29,1±2,4 and 29,0±2,4), OI (29,5±1,9, 29,6 ±2,9 and 29,2±2,7). X2: OD 15,8, OI 19,0 (p<0,001).
RP mean K(D): OD (48,7±6,1, 49,3±6,4 and 48,4±5,0), OI (48,4±5,1, 48,2±4,8 and 48,0±4,2). X2: OD 5,0 (p<0,79), OI 0,1 (p<0,909).
TCP (D): OD (47,3±5,2, 47,4±4,9 and 46,2±4,2), OI (47,2±4,7, 47,0±4,5 and 46,5±3,6). X2: OD 4,7(p<0,091), OI 0,4 (p<0,807).
Conclusions
The analysis of tomographic parameters studied in this patient sample indicates a statistically significative progression of morphological changes in the anterior corneal surface over a 10-year follow-up period. However, parameters obtained by ray tracing related to corneal refractive power did not undergo statistically changes throughout this time. While these morphological changes may not appear clinically significant in terms of vision and refraction, they do underscore the importance of long-term follow-up and monitoring patients with this condition, even if their visual acuity remains unchanged.