epidermal

Of or pertaining to the epidermis; epidermic; cuticular.

Pertaining to or emanating from epidermis.

• e. appendage — see hair, claw, hoof, horn, chestnut (1), ergot2, dewclaw, comb, wattle, spur (3), pad, footpad, beak, frontal process, feather (1), cere, scale, fin, antler, bristle (1), wool, mohair, cashmere, angora.
• e. clefts — slit-like discontinuities in the epidermis that do not contain fluid.
• e. collarette — a feature of a skin lesion, consisting of an encircling rim of epidermal scale with the free edge toward the central area. May represent the margins of an earlier bulla, vesicle or pustule. Characteristic of bullous pemphigoid.
• e. crust — a consolidated mass of cellular debris, dried exudate, serum, hair, epidermophytic hyphae. Usually is dry and crumbly but in parakeratosis may have a greasy feel about it.
• e. cyst, epidermoid cyst — an intradermal or subcutaneous cyst containing keratinizing squamous epithelium. It arises from occluded hair follicles. Called also infundibular cyst, wen.
• e. dysplasia — abnormal development of individual cells of the epidermis. In West Highland white terriers, a familial skin disease characterized by seborrhea, pruritus, alopecia and lichenification from an early age. Infection by Malassezia spp. is a common feature. See also inherited epidermal dysplasia of calves.
• e. growth factor — a potent growth factor for both epithelial and fibroblast cells.
• e. lacunae — see epidermal clefts (above).
• e. laminae — structures formed of epidermal pegs; part of the interdigitating structure between the dermis and the epidermis. Called also epidermal ridges.
• e. limbi — the layer of soft, light-colored horn that covers the outer side of the coronary border and merges with the horn of the hoof.
• e.-melanin unit — a melanocyte and adjacent keratinocytes.
• e. necrolysis — see toxic epidermal necrolysis.
• e. nibbles — focal areas of epidermal edema, eosinophils and necrosis; suggestive of ectoparasite injury to the skin.
• e. papilla — a knob-like projection of the epidermis into the dermis; a touch receptor. Called also tylotrich pad and haarscheiben.
• e. pegs — see rete pegs.
• e. renewal time — see keratinocyte transit time.
• e. ridge — see rete ridge.