Hearing and Vestibular

Question 1

Structure of the Ear

Answer 1

External and Middleear: function in capturing, transmitting, and amplifying sound.
Inner ear: contains the receptive organs that are stimulated by sound waves (hearing) or head position and movement (vestibular function).

Question 2

Disorders of the Middle Ear

Answer 2

Acute Otitis Media in Children: acute onset; middle ear effusion; inflammation; recurrent.

Otitis Media (OM): an infection of the middle ear that is associated w/ a collection of fluid.

Otitis Media with Effusion: the presence of fluid in the middle ear w/out signs and symptoms of acute ear infection.

Otosclerosis: the formation of new spongy bone around the stapes and oval window, which results in progressive deafness. Bone increasingly immobilizes the stapes, reducing the transmission of sound.

Question 3

Disorders of Vestibular Function

Answer 3

CNS lesions involving the cerebellum and lower brain stem.

**Vertigo: an illusion of motion occurs. the person may be stationary and the environment in motion (objective vertigo) or the person may be in motion and the environment stationary (subjective vertigo).

Motion sickness: a form of normal physiologic vertigo. caused by repeated rhythmic stimulation of vestibular system, such as is encountered in car, air, or boat travel.

Question 4

Disorders of Peripheral Vestibular Function

Answer 4

Benign paroxysmal positional vertigo: these signals are distorted. sudden onset of dizziness or vertigo that is provoke by certain changes in head position.

Ménière disease: these signals are unbalanced by unilateral involvement of one of the vestibular organs. fluctuating episodes of tinnitus, feelings of ear fullness, and violent rotary vertigo that often renders the person unable to sit or walk.

Question 5

Ménière Disease

Answer 5

**Pathophysiology: altered vestibular function. Increased volume of endolymph leads to dilation of the membranous labyrinth of the inner ear.

Clinical manifestations: **often unilateral; class TRIAD of symptoms; 1.) hearing loss 2.) vertigo 3.) tinnitus

variable in severity

Question 6

Central Causes of Vertigo

Answer 6

**Abnormal nystagmus and vertigo can occur as a result of CNS lesions involving the cerebellum and lower brain stem.

Question 7

Hearing Screening

Answer 7

**Conductive: stimuli are not adequately transmitted.
Sensorineural: disorders that affect the inner ear, auditory nerve, or auditory pathways of the brain.
Mixed

Question 8

Treatment for Hearing Loss

Answer 8

**Special consideration for children