What characteristic is unique to plaques in dermatology?

Plaques are distinctive dermatological lesions that are raised and possess a flat surface, which differentiates them from other types of skin lesions. This characteristic of being raised allows them to stand out prominently from the surrounding skin, while the flat surface gives them a unique appearance that can be observed visually and palpated.

The definition of plaques typically encompasses lesions that are larger than 1 centimeter in diameter and are formed by the coalescence of papules, which can occur in various skin conditions such as psoriasis, eczema, and others. The clear demarcation of their raised structure and the flat top can be crucial for accurate identification during a clinical examination.

Attributes like being blister-like, larger than a nodule, or having associations with histamine release do not apply to plaques, as these features are characteristic of other types of skin conditions. Focusing on the flat surface aspect, combined with the raised nature, is key to understanding the definition and clinical significance of plaques in dermatology.