Regular hyperpigmented structureless areas (regular blotch)
Regular blotches are defined as those that display symmetry, regular borders,homogenous dark hue, and are located within the center of the lesion. A pigment network often surrounds a regular blotch. Regular blotches are associated with nevi.
Regular blotches can be seen in “activated” nevi and are attributed to heavy melanin concentrations in the stratum corneum. Because the pigment is concentrated in the stratum corneum, it can easily be stripped off using a tape-stripping procedure, thereby revealing underlying structures.