Guidance Document on the Collection of Eyes Tissues for Histological Evaluation and Collection of Data ‑ Second Edition

This Guidance Document accompanies the OECD Test Guideline (TG) 437 on the bovine corneal opacity and permeability (BCOP) test method and TG 438 on the isolated chicken eye (ICE) test method. It provides users with guidelines for collecting histopathology data for in vitro and/or in vivo ocular safety test methods. The primary purposes of this GD are: i) to promote the collection of histopathological data; (ii) to provide guidance on performing histopathological evaluations; (iii) to support further understanding of the usefulness and limitations of histopathology as an additional endpoint to improve the accuracy of in vitro ocular safety test methods; iv) to provide comprehensive protocols on the BCOP and ICE test methods to promote harmonisation of approaches; and v) for those test chemicals (i.e. substances and mixtures) that are tested as a last resort, in vivo, to provide standard procedures for enucleating, fixing, and processing eyes from the in vivo rabbit eye studies for histopathological evaluation.