Spontaneous Background and Procedure-Related Microscopic Findings and Common Artifacts in Ocular Tissues of Laboratory Animals in Ocular Studies

Toxicol Pathol 2021.49:569-580 -- In all toxicology studies, the differentiation of microscopic findings induced by a test article from the spontaneous background findings that may occur in the tissues of a given species is critical. In ocular toxicology studies, additional potentially confounding factors include findings induced by the administration procedure itself or artifacts associated with the collection or fixation of the eye. The objective of this article is to provide a mini-atlas of the artifacts and the procedure-related and background findings commonly encountered in ocular tissues from animals in toxicology studies of ocular drug candidates. We also include some uncommon background, species-specific findings that may be confused with test article-related findings if the study pathologist is unaware that these may occur in control animals.