Cite this page: Pernick, N. Normal histology. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/earnormalhistology.html. Accessed October 20th, 2018.
- Pinna: resembles skin elsewhere with keratinized, stratified squamous epithelium, dermal adnexal structures, subcutaneous fibroconnective tissue, fat and elastic fibrocartilage which provides support
- External auditory canal: lined by thin keratinized stratified squamous epithelium covering scant fibrous stroma along entire canal and covering external tympanic membrane
- Outer third contains ceruminous glands (modified apocrine glands) deep within dermis that produce cerumen; glands are in clusters of cuboidal cells with intensely eosinophilic cytoplasm with apical snouts and containing golden yellow, granular pigment and secretory droplets along luminal border; glands are surrounded by myoepithelial cells; outer canal contains cartilage not bone
- Inner two thirds has very thin epidermis which lacks rete pegs, no / reduced number of ceruminous glands and dermal adnexa; contains bone not cartilage
- Cerumen: watery fluid devoid of lipids; drains from glands into ducts which open into hair sacs of ear canal hairs; fluid mixes with sebaceous gland secretions to produce cerumen (wax)
- Tympanic cavity: thin fibrous structure lined by attenuated keratinizing squamous epithelium on external canal side