Ear canal

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Ear Canal

The ear canal, also known as the external auditory meatus, is a tube running from the outer ear to the middle ear. The human ear canal extends from the pinna to the tympanic membrane (eardrum) and is a key component of the auditory system, playing a critical role in the process of hearing.

Anatomy

The ear canal is approximately 2.5 centimeters in length and is S-shaped in adults, which helps protect the eardrum from damage. It is divided into two parts: the outer one-third is cartilaginous and has hair follicles as well as sebaceous glands and ceruminous glands that produce earwax (cerumen). The inner two-thirds are bony and lack hair and glands. The skin lining the ear canal is thin, especially near the eardrum, making it sensitive and susceptible to infections.

Function

The primary function of the ear canal is to conduct sound waves from the outer ear to the eardrum. The ear canal also serves to protect the middle ear from foreign particles, bacteria, and fungi. Earwax plays a crucial role in this protective function, trapping dirt and debris and inhibiting the growth of microorganisms.

Common Conditions

Several conditions can affect the ear canal, including:

• Otitis externa: An infection of the ear canal, often referred to as "swimmer's ear."
• Earwax impaction: Accumulation of earwax that can block the ear canal, leading to hearing loss or discomfort.
• Exostoses: Abnormal bone growths within the ear canal, commonly seen in surfers, hence the name "surfer's ear."

Diagnosis and Treatment

Diagnosis of ear canal conditions typically involves a physical examination, which may include an inspection of the ear canal and eardrum using an instrument called an otoscope. Treatment varies depending on the condition but may include cleaning, medication (e.g., antibiotics for infections), or, in some cases, surgery.

Prevention

Preventive measures for ear canal health include avoiding the insertion of foreign objects into the ear, keeping the ears dry (especially after swimming), and managing earwax production. Over-cleaning of the ear canal, particularly with cotton swabs, can lead to irritation and should be avoided.