Tinnitus
and Hearing Loss
Sensorineural
hearing loss- loss of sound perception due to any disorder from the oval or
round window to the brain due to trauma, infection, congenital causes, etc.
Conduction
hearing loss-loss of sound perception due to the blockage of the sound waves
due to blockage, infection, swelling, trauma, perforations, congenital
malformation, etc.
Tuning
fork tests
512
cps. is best but you can use a 256 tuning fork.
128
cps. vibratory waves are too large.
Rinne
normal air conduction is two times longer than bone conduction [recorded as positive]
abn. air conduction is less than two times bone conduction [recorded as negative]
Weber
lateralized sound to one ear
The sound will be heard in the ear
with the conductive hearing loss.
It may also mean there
is a sensorineural loss in the other ear.
Tinnitus: noises in the ear, real or imagined.
Most
common in those exposed to long-term, high intensity sound.
The
TMJ, eustachian tube and carotid artery can produce sound which are usually
benign and can be heard by the doctor [objective tinnitus] as well as the
patient.
Physiologic
causes, such as ototoxicity, neurologic or mechanical problems may also be
causative factors.
Rule
of thumb
High
pitched: sensorineural
Rushing, hissing, buzzing, whine
Neurologic or physiologic [systemic]
typically
Low
pitched: conductive
Mechanical, such as Otitis Media,
foreign objects, etc.
q
Persistent
noise exposure
Ringing
or cricket sounds
[high
pitched as the labyrinthe hair cells and their nerves have been over
stimulated]
[most
often the hardest hit frequencies during the exposure]
If
short-term exposure, the tinnitus should be temporary.
Have
the patient screened for sensorineural hearing loss if it persists.
q
Acoustic
neuroma
Constant
tinnitus that begins faint and gets louder as the tumor grows
High
pitched [the nerve is affected]
Vertigo
accompanies this condition.
It
comes on gradually, as does the tinnitus, so the patient may be able to
compensate fairly well, so only ataxia may be seen.
A
benign, expansile lesion located anywhere along the 8th cranial
nerve from the cochlea to the brainstem.
Other
sign and symptoms depend on the location and size of the tumor.
If
the patient has loss of the corneal reflex, the growth of the tumor is also
compromising the 5th cranial nerve.
If
facial palsy is present, the 7th cranial nerve is compromised.
This
is a benign tumor but death may occur if it gets large enough to significantly
change the intracranial pressure.
q
Hypertension
Constant,
high pitched
Due
to hypoxia form the typically associated atherosclerosis
q
Anemia
Constant,
high pitched
Due
to hypoxia from lack of adequate oxygen carrying capacity of the blood
q
Ototoxicity
Constant,
high pitched
Active
metabolic processes of the inner ear are very susceptible to drug
influences.
Those
that affect the renal system will often affect the inner ear [aminoglycosides,
cytotoxic agents, salicylates and quinine].
Hypervitaminosis.
q
Diabetes,
syphillis and other systemic diseases
Sensorineural
hearing loss with tinnitus due to neurologic changes
q
Presbycusis
Tinnitus
due to aging
Usually
associated with sensorineural hearing loss
Due
to its gradual onset, the patient may not be aware of the hearing loss until it
is accentuated by a cold that causes a temporary conductive loss.
Aging
leads to a degeneration of the haircells of the Organ of Corti and the cochlear
nerve fibers.
The
patient will play the TV loudly and complain that people mumble.
Masking
may cover the tinnitus so the patient can sleep.
Hearing
screening is necessary.
q
Torus
tubaris dysfunction
The
os may stick open causing a rushing, blowing or swishing sound in the ear and
the patient will hear themselves talking into the ear.
q
Foreign
body in the middle ear
A
phlebolith can break free and is heard by the patient when moving the head.
Listen
to the ear with the stethoscope while the patient moves the ehad.
q
Meniere’s
Disease or Multiple Sclerosis
Unilateral
tinnitus with hearing loss and vertigo
[see
notes on vertigo]
q
Bell’s
Palsy
Most
common cause of facial paresis
Path
of nerve is long and tortuous
The
site of lesion often will help with dx.
Further,
watch for other S&S: vessicles
[herpes zoster], positive findings behing TM [cholesteatoma], fever, etc.
Dx
by exclusion- perform full cranial nerve and neuro examination
If
shoulder shrug, vagus or corticospinal tract signs refer [CVA, Trauma, MS,
encephalitis, etc.]
Most
often idiopathic, but can be due to…
congenital,
traumatic,
infection
[middle ear, herpes zoster oticus [Ramsey hunt Syndrome], HIV, lyme ds., TB,
mono, flu, etc.],
neoplasia
[acoustic neuroma, meningioma, parotid tumor],
metabolic
[diabetes, pregnancy, hyperthyroidism, autoimmune],
neurologic
[MS, Guillain-Barre’]
fullchart
Page 196 Lee
Lyme
disease- most common presentation of this disease early on. Unlike Bell’s Palsy, it presetnts with
general flu-like symptoms and the bulls eye rash
Infection
in middle ear can impinge the nerve- OM, malignanat OM, cholesteatoma,
mastoiditis, serous OM]
The
infranuclear portion of facial nerve is affected
[further,
the upper lid motion is intact as it [the levator palpevrae muscle] is
innervated by the occulomotor nerve!
therefore
a lower motor neuron paralysis with
both
the upper and lower facial muscles involved in the presentation.
Review: The facial nerve, VII, is a mixed nerve with
a complex course from the brain stem to the temporal bone and parotid
gland.
It
innervates the muscles of facial expression and supplies sensory for the
anterior two thirds of the tongue.
Further, there are secromotor fibers for the following glands: lacrimal,
submandibular and sublingual.
It
travels form the pons and geniculate ganglion and it traverses through bony
foramen, inner and middle ear and the parotid.
Commonly
caused by herpes virus though many other infectious agents are possible.
It
is a case of neuropraxia as the nerve swells within the bone causing conduction
block.
Medical
treatment, including nutritional, according to Lee, does not seem to make a
difference in the recovery.
The
site of the lesion will determine the symptoms.
Unilateral
facial paresis over 2-3 wks.,
Sensorineural
hearing loss,
Hyperacusis,
Diminished
tearing
Altered
taste
Tinnitus
[innervation of stapedius muscle]
Pain
around the ear,
eyelid
fasciculation, facial twitch.
Commonest
cause of facial paresis
Supranuclear
lesions are strokes and the frontalis muscle is not involved.
A
diagnosis of exclusion.
Pain
or discomfort around the mastoid may precede the palsy
Loss
of hearing, taste and hyperacusis may be present.
When
the palsy is incomplete, 90% of patients recover within 6 weeks of onset.
If
the palsy keeps increasing after 3 weeks or not resolved after 6 months,
neoplasm should be considered
Neuro
consult if not!
See
chart p. 199 Lee for differential dx
Note: Facial palsy may be due to trauma to the
facial nerve from cholesteatoma, parotid tumor, acoustic neuroma, or facial
nerve tumor.
q
Cerebral
tumor
Intermittent
tinnitus with aura and seizure
q
Carotid
stenosis, arteriovenous aneurysm, nasopharyngeal carcinoma
Low,
pulsing swish synchronous with the heartbeat
q
Any
air conduction hearing loss
Otitis
media, otitis externa with moderate to severe swelling, any eustachian tube
dysfunction
Low
pitched on the side of involvement
May
be intermittent or constant depending on the cause
Perforated TM- constant
Serous OM- intermittent low pitched
if the eustachina tube drain occasionally
Foreign body: constant, low pitch
Note: a conductive hearing loss may lead the patient
to have tinnitus associated with chewing
q
Myofascitis: typically of the muscles of mastication,
esp. the upper posterior deep masseter
It
will refer motor unit activity to the stapedius muscle causing movements of the
ossicles
No
hearing deficit
Causes: cutting thread with teeth, chewing ice,
incessant gum chewing, pipe stem holding with teeth, cracking nuts, mouth
breathing, emotional tension, occlusal disharmony.
Check
the TMJ.