Ch. 1 - Normal anatomy Flashcards
Scalp skin
Numerous follicles extending into the panniculus with associated sebaceous glands and arrector pili muscle
Facial skin
Thin epidermis, basket-weave stratum corneum, demodex mites.
Truncal skin
Thick dermis, fewer adnexal structures but enveloped with projections of fat.
Areolar skin
Slight acanthosis, basilar hyperpigmentation, apocrine glands, smooth muscle bundles.
Acral skin
Compact eosinophilic stratum corneum and slight papillomatosis on dorsal surfaces
Volar skin
Compact eosinophilic hyperkeratosis with underlying stratum lucidum. Eccrine glands & meissner/pacinian corpuscles. No hair.
Eyelid
No hair follicles or stratum corneum, but goblet cells are present.
Mucosa
Absent granular layer, glycogenated keratinocytes, smooth muscle bundles and dilated vessels.
Nasal turbinate
Erectile tissue with fibrous septa, mucous glands, and vascular sinusoids
Fetal skin
Stellate and spindled fibroblasts (mesenchyme). Densely cellular.
Hair (infundibulum)
Most superficial (to sebaceous gland insertion). Keratinizes in the pattern of the normal epidermis with a granular layer. Intraepidermal portion is the “acrotrichium”
Hair (isthmus)
From sebaceous gland to insertion of arrector pili. Keratin formed without granular layer (trichilemmal keratinization). Inner root sheath lost at this level.
Hair (stem)
From insertion of arrector pili to Adamson’s fringe (where hair cornifies). Only present in anagen hairs.
Hair (bulb)
From Adamson’s fringe to base of follicle. Matrix, Supramatrix, and Keratogenous zones.
Nail anatomy (key features)
Nail plate, nail bed, framing portion, ensheathing portion (eponychium, hyponichium, solehorn, bed horny layer)
