Primary care doctors often diagnose and treat disorders involving the ear, nose, and throat, but doctors called otolaryngologists or otorhinolaryngologists are the ones who specialize in such disorders. The ears, nose, and throat have separate but related functions. The ears and nose are sensory organs, which are necessary for the senses of hearing, balance, and smell. The throat mainly functions as a pathway through which food and fluids travel to the esophagus (the hollow tube that leads from the throat to the stomach) and air passes to the lungs.
Ear, Nose, and Throat Disorders
Ear, Nose, and Throat Disorders Chapters (A-Z)
Biology of the Ears, Nose, and Throat
The ears, nose, and throat are located near each other and have separate but related functions. The ears and nose are sensory organs, which are necessary for the senses of hearing, balance, and smell. The throat mainly functions as a pathway through which food and fluids travel to the esophagus (the hollow tube that leads from the throat to the stomach) and air passes to the lungs. Primary care doctors often diagnose and treat disorders involving these organs, but doctors called otolaryngologists specialize in them.
Hearing Loss and Deafness
Overall, about 10% of people in the United States have some degree of hearing loss. The incidence increases with age. Although less than 2% of children under 18 have a permanent hearing loss (see see Hearing Impairment in Children), hearing loss during infancy and early childhood can be detrimental to language and social development. Over one third of people over 65 years and over half of people over age 75 are affected.
Inner Ear Disorders
The fluid-filled inner ear (labyrinth) consists of two major parts: the organ of hearing (cochlea) and the organ of balance (vestibular system, which consists of the semicircular canals, the saccule, and the utricle). Disorders of the inner ear can affect hearing, balance, or both. Middle ear disorders (see Middle Ear Disorders) cause many of the same symptoms, and a disorder of the middle ear may affect the inner ear and vice versa.
Middle Ear Disorders
The middle ear consists of the eardrum (tympanic membrane) and an air-filled chamber containing a chain of three bones (ossicles) that connect the eardrum to the inner ear (see see Ears : Middle Ear). The middle ear acts as an amplifier of sound, whereas the inner ear acts as a transducer, changing mechanical sound waves into an electrical signal that is sent to the brain via the nerve of hearing (statoacoustic nerve). Middle and inner ear disorders (see Inner Ear Disorders) cause many of the same symptoms, and a disorder of the middle ear may affect the inner ear and vice versa.
Mouth and Throat Disorders
Disorders of the throat (pharynx) and voice box (larynx) may represent short-lived (acute) inflammation and infections, persistent (chronic) inflammation, or abnormal growths that are more common among adults. Specific disorders include vocal cord polyps and nodules, contact ulcers, vocal cord paralysis, laryngoceles, laryngeal papillomas (see Recurrent Respiratory Papillomatosis), and cancer (see Mouth, Nose, and Throat Cancers). However, vocal nodules, papillomas, and laryngoceles may occur as commonly among children.
Mouth, Nose, and Throat Cancers
Cancers of the mouth, nose, and throat develop in almost 60,000 people in the United States each year. These cancers are more common among men, but the percentage of affected women is rising because smoking has increased among women. Most affected people are between the ages of 50 and 70. However, these cancers are occurring more often in younger people.
Nose and Sinus Disorders
The upper part of the nose consists mostly of bone. The lower part of the nose gains its support from cartilage. Inside the nose is a hollow cavity (nasal cavity), which is divided into two passages by a thin sheet of cartilage and bone called the nasal septum. The bones of the face contain the paranasal sinuses, which are hollow cavities that open into the nasal cavity (see Nose and Sinuses).
Outer Ear Disorders
The outer ear consists of the external part of the ear (pinna or auricle) and the ear canal (external auditory meatus—see see Figure: A Look Inside the Ear). Disorders of the outer ear include blockages (obstruction), foreign bodies, infections (external otitis, malignant external otitis, and perichondritis), dermatitis, and tumors. The outer ear is also prone to certain types of injury (see Ear Injury).