What are tan or greasy corneal opacities primarily associated with?

Tan or greasy corneal opacities are primarily associated with keratic precipitates. Keratic precipitates are deposits of inflammatory cells, lipid, and other materials that accumulate on the corneal endothelium. These precipitates can appear as various opacities, such as greasy or tan patches, and are typically a result of chronic inflammation in the eye, often seen in conditions like uveitis or other intraocular inflammatory processes.

The presence of these opacities indicates an underlying issue that leads to inflammation and disruption of the normal corneal architecture. Identifying keratic precipitates is important in diagnosing and managing conditions that may lead to more severe ocular complications. In contrast, corneal ulcers, cataracts, and corneal dystrophies involve different pathological processes and present with distinct signs and symptoms that do not typically manifest as tan or greasy opacities on the cornea.