Flashcards in Week 6- ENT Deck (51)
Ear development occurs at the same time as ___ development- malformation or dysfunction in one system should alert the healthcare provider to problems in the other.
The external ear comprises:
Auricle and ear canal
In the air filled middle ear these structures transform sound vibrations into mechanical waves for the inner ear:
Ossicles- the malleus, the incus, and the stapes
The proximal end of ___ connects the middle ear to the nasopharynx.
The Eustachian tube
The inner ear includes:
The cochlea, the semicircular canals, and the distal end of the auditory nerve (vestibulocochlear nerve or CN VIII)
Movements of the ___ vibrate the perilymph in the labyrinth of the semicircular canals and the hair cells and endolymph in the ducts of the cochlea, producing electrical nerve impulses transmitted by the auditory nerve to the brain.
The first part of the hearing pathway, from the external ear through the middle ear, is known as:
The conductive phase
The second part of the hearing pathway, involving the cochlea and the cochlear nerve is:
The sensorineural phase
____ describes the normal first phase in the head pathway.
A vibrating tubing fork, placed on the head, sets the bone of the skull into vibration and stimulates the cochlea directly.
In normal hearing what is more sensitive: bone or air conduction?
AC is more sensitive than BC
( AC > BC)
Nontender modular swellings covered by normal skin deep in the ear canals that are non malignant overgrowths which may obscure the drum:
Movement of the auricle and tragus (tug test) is painful in:
Acute otitis externa
Tenderness behind the ear occurs in:
In an adult, to see the internal structures by straightening the ear canal:
Pull the auricle upward, backward, and slightly away from the head.
Cone of light in right ear:
At 5 o’clock
Cone of light in the left ear:
Most specific and sensitive hearing test?
Whispered voice test - sensitivity 90-100% and specificity 70-87%. Defects significant hearing loss of greater than 30 decibels.
These tests may be done for patients failing the whispered voice test to help determine if hearing loss is conductive or sensorineural:
Weber and Rinne
Weber test is used for:
Unilateral hearing loss only
In unilateral conductive hearing loss sound is heard in what ear with the Weber test?
Impaired ear: explanations include otosclerosis, otitis media, perforation of the eardrum, and cerumen.
In unilateral sensorineural hearing loss with the Weber test, sound is heard in:
The good ear.
What tests compares air conduction and bone conduction?
What is normal finding for the Rinne?
AC > BC
In conductive hearing loss with the Rinne test, sound is:
Heard through bone as long or longer than it is through air ( BC = AC or BC >AC)
In sensorineural hearing loss with the Rinne test, sound is heard:
Longer through air (AC > BC)
A pneumatic scope with peds patient allows puff of air to go into air canal and TM should flutter with air; if TM fails to move:
Likely middle ear effusion
Eustachian tube in peds is:
Shorter, wider, and more horizontal than an adults allowing for pathogens from the nasopharynx to migrate through to the middle ear.
This part of the ear transmits sound by vibrations of the TM causing the ossicles and oval window to set the inner ear fluids in motion: