Scheimpflug-Based Analysis of the Reflectivity of the Cornea in Marfan Syndrome

PURPOSE: We sought to investigate corneal reflectivity in Marfan syndrome (MFS) on the basis of Scheimpflug light intensity distribution. METHODS: In a retrospective case-control analysis, the left eyes of 40 MFS patients and 40 age- and refraction-matched healthy controls were investigated. Patients with MFS meeting the Ghent II diagnostic criteria and with genetic confirmation of disease were included. Exclusion criteria were the following: coexisting corneal, conjunctival, or scleral pathology; use of medication known to affect corneal transparency; history of ocular surgery; and insufficient data. Scheimpflug tomography images were exported to analyze corneal transparency in different corneal layers and regions. Each corneal image was automatically segmented, after which the corresponding pixel intensities in the defined regions of interest were statistically modeled using a Weibull probability density function from which parameters α (transparency) and β (homogeneity) were derived. RESULTS: The cornea in MFS showed significantly higher light reflectivity (overall cornea, α = 71 ± 17 arbitrary units (a.u.)) than in the control group (overall cornea, α = 59 ± 15 a.u.) (t test, P = 0.003). The α parameter was significantly higher in MFS eyes in all examined layers and regions (P < 0.05), whereas the β parameter showed no statistical difference between MFS and controls (P > 0.05). The difference in α did not correlate with ocular biometric properties (corneal thickness and curvature) or ectopia lentis (P > 0.05). CONCLUSIONS: The cornea in MFS shows significantly higher reflectivity than healthy controls with similar levels of homogeneity. TRANSLATIONAL RELEVANCE: The proposed methodology detects corneal reflectivity changes in MFS not available from regular slit-lamp examination.