ESCRS - PP11.08 - Corneal Biomechanical Deterioration Is Worse In Paediatric Keratoconus Than In Adult Keratoconus Cases Matched For Tomographic Disease Severity

Corneal Biomechanical Deterioration Is Worse In Paediatric Keratoconus Than In Adult Keratoconus Cases Matched For Tomographic Disease Severity

Published 2023 - 41st Congress of the ESCRS

Reference: PP11.08 | Type: Free paper | DOI: 10.82333/shyx-cf32

Authors: Bernardo Lopes* 1 , Riccardo Vinciguerra 2 , Paolo Vinciguerra 3 , Renato Ambrosio Jr 4 , Arvind Chandna 5

1Ophthalmology,Federal University of Sao Paulo,Sao Paulo,Brazil, 2Humanitas San Pio X,Milan,Italy, 3Humanitas University,Milan,Italy, 4Ophthalmology,Federal University of the State of Rio de Janeiro,Rio de Janeiro ,Brazil;Ophthalmology,Federal University of Sao Paulo,Sao Paulo,Brazil, 5Smith Kettlewell Eye Research Institute,San Francisco,United States;Alder Hey Children's Hospital,Liverpool,United Kingdom

Purpose

To compare the degree of corneal biomechanical deterioration between Paediatric Keratoconus (pKC) patients and Adult Keratoconus (aKC) patients

Setting

Instituto de Olhos Renato Ambrosio (Rio de Janeiro, Brazil), Vincieye Clinic (Milan, Italy).

Methods

A dataset of KC cases examined in the two clinics was reviewed retrospectively. Sixty-one children with pKC, mean age 15.6 ± 1.9 years (6 – 17) were identified. A matched cohort of 61 aKC adults, mean age 45.4 ± 8.0 years (35 – 67) was selected to achieve the minimum difference in tomographic parameters: the mean 3mm corneal central anterior (ARC) and posterior radii of curvature (PRC) and minimum corneal thickness (mCT). Three biomechanical indices; one related to the corneal material properties:  the Stress-Strain index (SSI) and two related to the overall corneal stiffness: the Stiffness-Parameter at the first applanation (SP-A1) and the integrated inverse radius (IIR); were chosen and their correlation with KC severity was analysed.

Results

Based on these 3 indices, the corneal biomechanical deterioration was significantly higher in the paediatric group. The SSI was 0.67 ± 0.10 (0.47 – 0.95) in pKC and 0.99 ± 0.13 (0.74 – 1.26) in aKC (p<0.001). Similarly, SP-A1 was significantly lower in the pKC (69.6 ± 21.0 mmHg/mm (22.5 – 117.2) than in the aKC (76.9 ± 16.6 mmHg/mm (38.7 –  118.7), p=0.028) and IIR was significantly higher in the pKC (11.7 ± 2.4 mm-1 (6.8 – 18.8) than in the aKC (10.7 ± 1.9 mm-1 (5.9 – 15.3), p=0.033) indicating significantly softer corneas in the pKC group. The correlations between the three indices (SSI, SP-A1 and IIR) and KC severity were significantly stronger in the pKC group (p<0.05).

Conclusions

This study demonstrated that there is a greater degradation in corneal biomechanics in paediatric eyes which may explain the more aggressive nature of the disease in these cases. In addition, the greater correlation of biomechanical parameters with the disease severity in the paediatric population suggests that the biomechanical indices could be good indicators for performing early cross-linking treatment in these patients to avoid disease progression.