JCAT Certified Ophthalmic Assistant (COA) Practice Test 2025 - Free COA Exam Practice Questions and Study Guide

A chalazion is a type of inflammation that occurs when a meibomian gland, which is responsible for producing the oil component of tears, becomes blocked. This blockage leads to the accumulation of oil and inflammation, resulting in a firm, painless lump on the eyelid. Chalazia can develop over time and may become red or swollen if there is secondary inflammation.

In contrast, a hordeolum, commonly known as a stye, affects the eyelash follicles and sebaceous glands and typically presents as a painful, localized swelling, which is more associated with acute infection rather than a blockage of the gland itself.

Psoriasis is a chronic skin condition characterized by red, scaly patches and is not specifically related to gland blockage on the eyelid. Dermatitis refers to skin inflammation that can manifest in various forms, including allergic reactions, but again does not align with the specific gland obstruction that leads to a chalazion.