Outer Ear

The outer ear is the visible, external portion of the auditory system. It consists of the pinna (the cartilaginous structure on the side of the head) and the ear canal (external auditory meatus), which extends from the outer opening to the eardrum. The pinna collects sound waves from the environment and channels them into the ear canal. Its shape helps with sound localization, particularly for determining whether sounds originate from in front of or behind the listener, and from above or below.

The ear canal is a slightly curved passage approximately 2.5 cm long in adults. It contains hair follicles and cerumen-producing glands, which protect the canal and eardrum from debris and microorganisms. The skin of the ear canal migrates slowly outward, carrying cerumen and debris with it as part of the ear's natural self-cleaning mechanism.

Problems affecting the outer ear, such as cerumen impaction, foreign bodies, or structural malformations like microtia, can cause conductive hearing loss by blocking or disrupting the transmission of sound to the eardrum.