Optical measurement of dioptric power and transparency of cornea stored in bioreactor

Abstract

AbstractPurpose Quantification of dioptric power (DP) and transparency (T) of stored corneas remain almost unmet in daily eye bank practice. Complementary to T, DP could help screening donors having had refractive surgery and selecting the best donor/recipient refractive matching. During the development of an innovative corneal bioreactor (BR) (patented) for preclinical research and long‐term storage, we took into account the possibility to integrate devices to perform these new quality controls. Aim: to present a device, named “frontofoco‐graft‐meter” (FGM) able to quantify DP and T of corneas in BRMethods measure of DP was based on the principle of magnification measurement and for T on the transmitted light over incoming light ratio. The FGM comprised a light source + specific chart made of parallel black lines + digital camera. Human corneas in the BR were pressurised at 15mmHg, with medium circulation in endothelial chamber, whereas epithelial chamber was filled with air during measurements. DP was compared to the power map provided by OCT (Tomey, Casia), and T measures to results provided by our previous device called ‘transparometer’ (based on the analysis of modulation transfer function). Measurements were done by 3 operators in a masked fashionResults For DP, agreement with OCT was good (within ±1 Dioptry). For T, measures were comparable with both devices. Inter‐rater agreement was good for DP and T. FGM took a limited place and could easily be integrate in eye banksConclusion the new FGM provides objective and reproducible QC of DP and T of corneas placed in the BR. Grants: ABM 2012, ANSM 2012, EFS 2012