Abstract
Purpose:
To analyse the relationship of the corneal deformation response parameters by dynamic ultra-high-speed Scheimpflug imaging in ocular hypertension (OHT), primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) using the Corvis® ST (Oculus Optigerate Germany) (CST).
Methods:
A prospective cross-sectional study was done at Birmingham and Midland Eye Centre, United Kingdom. Two hundred and sixty three eyes of patients diagnosed with OHT (n=44 eyes), normal tension glaucoma (n=34 eyes) and POAG (n=124 eyes) were assessed. A group of 60 normal eyes were included in analysis as a control. The patients underwent randomised examinations with Goldmann applanation tonometry (GAT) and CST. The corneal deformation response indices, intraocular pressure (IOP) and central corneal thickness (CCT) were measured by CST.
Results:
The correlation between the IOP by CST and by Goldmann applanation tonometry was very good across all study groups. (p<0.01) The OHT group showed a significant difference in corneal deformation response (applanation1 time, applanation1 velocity, highest concavity radius and amplitude) : p<0.01. Post Hoc Tukey’s analysis revealed variable significant difference of the corneal deformation parameters amongst the different diagnoses. The IOP was noted to influence the difference of the deformation amplitude among the study groups (p<0.01). The Scheimpflug corneal deformation response parameters were not affected by the CCT (p>0.05).
Conclusions:
Each diagnosis seemed to have its special corneal deformation characteristics. Further studies with larger samples of all glaucoma diagnoses will help to explore the role of corneal deformation response in identifying a possible diagnosis of glaucoma during pre-screening with a CST.
Keywords: 479 cornea: clinical science •
568 intraocular pressure