korvakanavan

Korvakanavan, in English often called the external auditory canal, is the outer part of the human ear that connects the external opening of the ear to the tympanic membrane. In Finnish usage, korvakanava refers to this passage, with korvakanavan being its genitive form.

Anatomy and structure: The canal is about 2.5 centimeters long and has two portions. The lateral two‑thirds are cartilaginous and the medial one‑third is osseous, embedded in the temporal bone. The canal is lined with skin that bears hair follicles and ceruminous glands, which produce ear wax (cerumen). The skin is thinner near the tympanic membrane. The eardrum marks the end of the canal, separating the outer ear from the middle ear. Sensory innervation comes from branches of the auricular nerves, contributing to sensation in the canal.

Function: The korvakanavan conducts sound from the external ear to the eardrum, aiding hearing. The cerumen and the canal’s skin help protect the middle and inner ear by trapping dust and microorganisms and by providing lubrication and antimicrobial properties.

Clinical relevance: The canal is a common site for medical issues. Cerumen impaction can reduce hearing and cause discomfort. Otitis externa (swimmer’s ear) is an infection of the canal often due to bacteria or fungi. Foreign bodies, canal stenosis, and certain tumors can also affect the canal and hearing. Treatment varies with the condition and may include cerumen removal, topical medications, or, in some cases, surgical intervention.