Fluid Reservoir Thickness and Corneal Edema during Open-eye Scleral Lens Wear.
Optom Vis Sci
; 97(9): 683-689, 2020 09.
Article
em En
| MEDLINE
| ID: mdl-32932398
ABSTRACT
SIGNIFICANCE:
There is debate concerning corneal oxygenation during scleral lens wear due to the potential additive hypoxic effect of a lens plus a fluid reservoir. This study investigated the agreement between theoretical models and empirical measurements of scleral lens-induced corneal edema with respect to central fluid reservoir thickness.PURPOSE:
The purpose of this study was to examine the effect of altering the fluid reservoir thickness on central corneal edema during short-term open-eye scleral lens wear and to compare these empirical measurements with predictive theoretical models.METHODS:
Ten participants (age, 30 ± 4 years) with normal corneas wore highly oxygen-permeable scleral lenses (141 Dk ×10 cm O2 (cm)/[(s) (cm) (mmHg)]) on separate days with either a low (mean, 144; 95% confidence interval [CI], 127 to 160 µm), medium (mean, 487; 95% CI, 443 to 532 µm), or high (mean, 726; 95% CI, 687 to 766 µm) initial fluid reservoir thickness. Epithelial, stromal, and total corneal edema were measured using high-resolution optical coherence tomography after 90 minutes of wear, before lens removal. Data were calculated or extracted from published theoretical models of scleral lens-induced corneal edema for comparison.RESULTS:
Scleral lens-induced central corneal edema was stromal in nature and increased with increasing fluid reservoir thickness; mean total corneal edema was 0.69% (95% CI, 0.34 to 1.04%), 1.81% (95% CI, 1.22 to 2.40%), and 2.11% (95% CI, 1.58 to 2.65%) for the low, medium, and high thickness groups, respectively. No significant difference in corneal edema was observed between the medium and high fluid reservoir thickness groups (P = .37). "Resistance in series" oxygen modeling overestimated the corneal edema observed for fluid reservoir thickness values greater than 400 µm.CONCLUSIONS:
Scleral lens-induced central corneal edema increases with increasing reservoir thickness, but plateaus at a thickness of around 600 µm, in agreement with recent theoretical modeling that incorporates factors related to corneal metabolism.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Esclera
/
Lágrimas
/
Edema da Córnea
/
Ajuste de Prótese
/
Lentes de Contato
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Optom Vis Sci
Assunto da revista:
OPTOMETRIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Austrália