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SECTION I — Diseases of Ear
Figure 20.1. Various types of hearing aids. (A) Body-worn. (B) Behind-the-ear type. (C) Spectacle type. (D) In-the-ear type.
Scan to play Hearing Aids.
9. Type of earmould.
10. The type of fitting, whether it is monoaural (one aid
only), binaural (one aid for each ear), binaural with
y-connection (one aid but two receivers, one for each
ear) or the contralateral routing of signals type.
croS (contraLateraL routing oF SignaLS). In this
type, microphone is fitted on the side of the deaf ear and
the sound thus picked up is passed to the receiver placed
in the better ear. This is useful for persons with one ear
severely impaired and helps in sound localization coming
from the side of the deaf ear. Now bone-anchored hearing
aids (see infra) are being preferred for single-sided deafness and have replaced the use of CROS aids.
Bone-anchored Hearing Aid (BAHA)
Bone-anchored hearing aid is a type of hearing aid which is
based on the principle of bone conduction. It is primarily
suited to people who have conductive hearing loss, unilateral
hearing loss and those with mixed hearing loss who cannot
otherwise wear “in the ear” or “behind the ear” hearing aids.
Bone-anchored hearing aids use a surgically implanted abutment to transmit sound by direct conduction
through bone to the cochlea, bypassing the external auditory canal and middle ear (Figure 20.2).
Figure 20.2. Appearances when sound processor is attached to
abutment.
BAHA has three components: (i) titanium fixture (ii) titanium abutment and (iii) sound processor (Figure 20.3).
The titanium fixture is surgically embedded in the skull
bone with abutment exposed outside the skin. The titanium fixture bonds with the surrounding tissue in a process
called osseointegration. The sound processor is attached to
Chapter 20 — Rehabilitation of the Hearing Impaired
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TABLE 20.1 INDICATIONS FOR BAHA
1. When air-conduction (AC) hearing aid cannot be used:
• Canal atresia, congenital or acquired, not amenable to
treatment.
• Chronic ear discharge, not amenable to treatment.
• Excessive feedback and discomfort from air-conduction
hearing aid.
2. Conductive or mixed hearing loss, e.g. otosclerosis and
tympanosclerosis where surgery is contraindicated.
3. Single-sided hearing loss.
137
Figure 20.3. Bone-anchored hearing aid (BAHA).
the abutment once osseointegration is complete which
usually takes 2–6 months after implantation. The BAHA
device transmits vibrations to the external abutment
which further vibrates the skull and cochleae.
canDiDacy ProFiLe. Bone-anchored hearing aids can
be used in:
1. People who have chronic inflammation or infection
of the ear canal and cannot wear standard “in the ear”
air-conduction hearing aids.
2. Children with malformed or absent outer ear and ear
canals as in microtia or canal atresia.
3. Single-sided deafness (see Table 20.1).
In the past, the contralateral routing of signal (CROS)
hearing aid was the only option available for rehabilitation of patients with single-sided deafness. Poor performance and aesthetic considerations limited the use of
CROS aids. The BAHA device can now be implanted on
the side of the deaf ear, and it transmits the sound by
means of bone conduction to the contralateral cochlea.
The BAHA is fixed on the deaf side and collects sound
waves to transmit to healthy cochlea of the other side.
This process eliminates the head-shadow effect and allows for hearing from both sides of the head. The BAHA
substantially improves speech recognition in quiet and in
noise compared with the CROS aids.
Surgery. The surgery is typically performed in a sin-
gle stage in adults. About 3 months are allowed for osseointegration before the sound processor can be attached.
A two-stage procedure is recommended in children in
whom the fixture is placed into the bone in the first stage.
After about 6 months to allow for osseointegration, a
second-stage operation is done to connect the abutment
through the skin to the fixture.
Complications of BAHA are few and may include oc-
casional failure to osseointegrate the implant and local
infections and inflammation at the implant site.
1. Piezoelectric devices. Piezoelectric devices operate by
passing an electric current into a piezoceramic crystal,
which changes its volume and thereby produce a vibratory signal. This piezoelectric transducer in turn is
coupled to the ossicles and drives the ossicular chain
by vibration.
Examples of such devices are Envoy, middle-ear trans-
ducer (MET or also called otologic device), Rion and
totally integrated cochlear amplifier (TICA).
2. Electromagnetic hearing devices. Electromagnetic
hearing devices function by passing an electric current
into a coil, which creates a magnetic flux that drives an
adjacent magnet. The small magnet is attached to one
of the ossicles of the middle ear to convey vibrations to
the cochlea.
An example of such a device is the vibrant soundbridge
device (previously known as the Symphonix device; now
being manufactured by MED-EL).
viBrant SounDBriDge Device. The vibrant sound-
bridge is a semi-implantable device made of two components: an internal and an external. The internal component
is called vibrating ossicular prosthesis (VORP) and is made
up of three parts: the receiver, floating mass transducer
(FMT) and a conductor link between the two. FMT is connected to the incus (Figures 20.4 and 20.5).
The external component is called the audio proces-
sor which is worn behind the ear. The audio processor
Implantable Hearing Aids
Implantable middle ear hearing aids represent a new
category of hearing devices that work on a direct drive
principle. Rather than delivering acoustic energy into
the external auditory canal (as with traditional hearing
aid systems), direct drive middle ear implant systems use
mechanical vibrations delivered directly to the ossicular
chain, while leaving the ear canal completely open.
Implantable middle ear devices are generally available
in two types:
Figure 20.4. Vibrant soundbridge middle ear implant.
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SECTION I — Diseases of Ear
Figure 20.5. Components of the vibrating ossicular prosthesis (VORP).
contains a microphone that picks up sound from the environment and transmits it across the skin by radiofrequency waves to the internal receiver.
canDiDacy ProFiLe. Appropriate candidates for direct drive middle ear hearing devices include adults aged
18 years and older with moderate-to-severe sensorineural
hearing loss. Candidates should have experience of using
traditional hearing aids and should have a desire for an
alternative hearing system.
Often, patients who are interested in seeking direct
drive middle ear hearing devices have experienced dissatisfaction regarding the sound quality of their current hearing aids. Other problems these patients feel with these
aids are discomfort due to the occlusion effect of the canal, wax occluding hearing aid mould and wax impaction
of the external auditory canal, inability to wear traditional
hearing aids due to sensitive ear canal skin and the inability to overcome acoustic feedback issues (see Table 20.2 for
disadvantages of conventional hearing aids).
ProceDure. The internal device is surgically implanted. The procedure is conducted under general anaesthesia. The receiver of the implant is positioned under the
skin over the mastoid bone via a standard cortical mastoidectomy and posterior tympanotomy approach; the
ossicular chain is visualized and the FMT is attached to
the long process of the incus. The middle ear structures
are not modified. Therefore, there is no significant impact
on the residual hearing of the patient.
Six to eight weeks after the procedure, the patient is
fitted with the external audio processor that attaches
magnetically to the back of the ear. The processor is then
programmed.
aDvantageS. A direct drive system provides mechani-
cal energy directly to the ossicles, bypassing the ear canal and the tympanic membrane. This eliminates many
of the inherent issues of conventional hearing aids such
as occlusion, feedback, discomfort and wax related problems. One major advantage of direct drive devices is the
ability to provide improved sound quality to the hearingimpaired subjects particularly in noisy environments.
B. IMPLANTS
Cochlear Implants
A cochlear implant is an electronic device that can provide
useful hearing and improved communication abilities for
persons who have severe to profound sensorineural hearing loss and who cannot benefit from hearing aids.
A cochlear implant works by producing meaningful
electrical stimulation of the auditory nerve where degeneration of the hair cells in the cochlea has progressed to a
point such that amplification provided by hearing aids is
no longer effective. Various cochlear implants are shown
in Figures 20.6–20.8.
components and Functioning oF a cochlear im-
plant (Figure 20.9). A cochlear implant has an external
and internal component.
1. External component. It consists of an external speech
processor and a transmitter. The speech processor may
be body worn or behind the ear type; the latter being
preferred.
TABLE 20.2 DISADVANTAGES OF CONVENTIONAL
HEARING AIDS
• Cosmeticallyunacceptableduetovisibility.
• Acousticfeedback.
• Spectraldistortion.
• Occlusionofexternalauditorycanal.
• Collectionofwaxinthecanalandblockageofinsert.
• Sensitivityofcanalskintoearmoulds.
• Problemtouseindischargingears.
Figure 20.6. MED-EL cochlear implants. (A) MED-EL C-401. (B) Sonata model with ear level speech processor.
Figure 20.7. Nucleus cochlear implant (Cochlear Corporation) with
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ear level speech processor.
Figure 20.8. Advanced bionics cochlear implant system.
2. Internal component. It is surgically implanted and
comprises the receiver/stimulator package with an elec-
trode array.
Sound is picked up by the microphone in the speech
processor. The speech processor analyses and codes
sounds into electrical pulses. The processor uses a variety
of coding strategies to deliver meaningful speech parameters from the acoustic stimulus to the nerve. Examples of
such strategies are simultaneous analogue strategy (SAS),
Chapter 20 — Rehabilitation of the Hearing Impaired
139
continuous interleaved sampling(CIS), spectral peak
(SPEAK) and advanced combination encoder (ACE).
The electrical impulses are sent from the processor to
the transmitting coil which in turn sends the signal to
the surgically implanted receiver/stimulator via radiofrequency. The receiver/stimulator decodes the signal and
transmits it to the electrode array. Current day implants
are multichannel processors with the electrode having a
linear array of electrode contacts used to deliver multiple
channels of current to different places along the basilar
membrane. The electrode array which has been placed
in the scala tympani of the cochlea stimulates the spiral
ganglion cells. The auditory nerve is thus stimulated and
sends these electrical pulses to the brain which are finally
interpreted as sound.
canDiDacy ProFiLe. Cochlear implants may be used
both in children and adults. The following criteria help
define candidacy for cochlear implantation:
1. Bilateral severe to profound sensorineural hearing loss.
2. Little or no benefit from hearing aids.
3. No medical contraindication for surgery.
4. Realistic expectation.
5. Good family and social support toward habilitation.
6. Adequate cognitive function to be able to use the device.
Candidates with such hearing impairment may be defined as prelingual or postlingual depending on whether they were deafened before or after the acquisition of
speech and language.
In children who have hearing impairment at birth or
early in childhood, early intervention with hearing aids
or a cochlear implant is vital for auditory stimulus. Auditory deprivation, i.e. lack of auditory stimulus in the early
developmental period causes degeneration in the central
auditory pathways. This will limit the benefit in terms of
speech and language acquisition following cochlear implantation.
outcomes oF cochlear implantation. Factors that
predict a successful clinical outcome are:
1. Previous auditory experience (postlingual patients or
prior use of hearing aids).
Figure 20.9. Principle of cochlear implant.
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SECTION I — Diseases of Ear
2. Younger age at implantation (especially for prelingual
children).
3. Shorter duration of deafness.
4. Neural plasticity within the auditory system.
Multichannel implants are the standard today and per-
form much better than single-channel devices. Postlingual children or adults achieve very good benefit. They
develop the ability to recognize speech with no or minimal lip reading or visual cues. They eventually can also
use the telephone.
Prelingually deafened children also develop good
speech understanding and language acquisition over a period of time. This can take a couple of years and requires
constant auditory-verbal training. Early age at implantation ensures better results and children can be implanted
at 12 months of age.
Prelingually deafened adults with no or little prior
auditory experience obtain very limited benefit from
cochlear implantation. They will however obtain sound
awareness.
eValuation. Thorough evaluation of the patient is very
critical in the selection of candidates for a cochlear implant. The main purpose is to determine if the patient is
medically and audiologically suitable for an implant. It
also helps the clinicians to predict and counsel the family
regarding the expected outcomes following the procedure.
Medical evaluation through detailed history and
physical examination is necessary to confirm fitness for
a general anaesthetic. The necessary preanaesthetic tests
will be required to be carried out. All candidates must be
fully vaccinated against meningitis (particularly Haemo-
philus influenzae type B, Pneumococcus and in some areas
Meningococcus).
Imaging of the temporal bone, cochlea, auditory nerve
and brain is carried out using CT and MRI. This is required to provide an image of the structure of the cochlea
and help identify any anomalies or pathology that may
complicate the implantation process.
Audiological evaluation may include some or all of the
following depending on the age of the patient:
• Pure tone audiogram
• Speech discrimination tests
• Tympanometry
• Otoacoustic emissions (OAE)
• Auditory brainstem responses (ABR)
• Auditory steady state responses (ASSR)
A hearing aid trial and evaluation is mandatory in deter-
mining the candidacy for cochlear implantation. This may
include aided free-field sound detection thresholds, as well
as aided speech perception and discrimination scores.
Speech and language evaluation is required to assess the
child’s communicative status and to determine any developmental language or articulation disorders. This will
also form a baseline for further evaluations postimplantation to help assess progress and identify areas of deficit in
speech perception. This in turn would aid in the programming of the patient’s device.
Psychological evaluation is performed where there may
be concerns regarding the cognitive status or mental
function of the patient. This is also important to identify
children who may have disabilities other than hearing
loss. This may provide information that is important
when counselling parents about expectations following
cochlear implantation.
surgery. The principle of cochlear implant surgery is to
place the electrode array within the scala tympani of the
cochlea. This allows the electrodes to be in close proximity to the spiral ganglion cells and their dendrites (that lie
in the modiolus and osseous spiral lamina of the cochlea,
respectively).
Surgery is carried out under general anaesthesia and is
similar to mastoid surgery. Once the patient is positioned,
prepped and draped, the position of the device is marked
and the incision planned. Flaps are elevated carefully so
as not to disrupt the blood supply. Usually, a two-layered
approach is chosen utilizing a flap of skin and subcutaneous tissue, followed by a second layer of musculoperiosteal flap. A pocket is created under the second flap and
a well or recess is drilled in the bone to house the receiver/stimulator.
There are broadly two surgical techniques to approach
the cochlea for implantation: (i) The facial recess approach
where a simple cortical mastoidectomy is done first and
the short process of the incus and the lateral semicircular
canal are identified. The facial recess is opened by performing a posterior tympanotomy. The stapes, promontory
and round window niche are identified. Cochleostomy
is then performed anteroinferior to the round window
membrane to a diameter of 1.0–1.6 mm depending on
the electrode to be used. (ii) The pericanal techniques where
a tympanomeatal flap is elevated to perform a cochleostomy either by endaural or postaural approach. In the
pericanal techniques a bony tunnel is drilled along the
external canal towards the middle ear. The examples of
pericanal techniques include the Veria and suprameatal re-
cess approach.
The device is placed in the “well” created and is secured with ties. The electrode array is gently and gradually inserted through the cochleostomy till complete insertion has been achieved. Electrophysiological testing is
carried out to check that the electrode impedances and
telemetry responses are satisfactory.
The wound is closed in layers and a mastoid bandage
applied.
postoperatiVe mapping (programming) oF deVice
and habilitation. Activation of the implant is done
3–4 weeks after implantation. Following this the implant
is “programmed” or “mapped.” Mapping is done on a regular basis during postoperative rehabilitation to fine-tune
the processor and get the best performance as the patient
gets used to hearing with the implant.
(Re) Habilitation is an essential part for those who
have undergone cochlear implantation. All patients need
auditory-verbal therapy. In auditory-verbal therapy, the
emphasis is laid on making the child listen and speak like
a normal person rather than use lip reading and visual
cues. Learning to listen takes time and requires concerted
efforts from the patient, the family and the person providing habilitation services.
Table 20.3 summarizes the complications of cochlear
implant surgery.
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141
TABLE 20.3 COMPLICATIONS OF COCHLEAR
IMPLANT SURGERY
Early complications Late complications
• Facialparalysis
• Woundinfection
• Wounddehiscence
• Flapnecrosis
• Electrodemigration
• Devicefailure
• CSFleak
• Meningitis
• Postoperativedizziness/
vertigo
• Exposureofdeviceand
extrusion
• Painatthesiteofimplant
• Migration/displacementof
device
• Latedevicefailure
• Otitismedia
Auditory Brainstem Implant (ABI)
This implant is designed to stimulate the cochlear nuclear complex in the brainstem directly by placing the
implant in the lateral recess of the fourth ventricle. Such
an implant is needed when CN VIII has been severed in
surgery of vestibular schwannoma. In these cases, cochlear
implants are obviously of no use. In unilateral acoustic
neuroma, ABI is not necessary as hearing is possible from
the contralateral side but in bilateral acoustic neuromas
as in NF2, rehabilitation is required by ABI.
Brainstem implant is similar to “Nucleus” multichannel cochlear implant except that the multielectrode array is attached to a Dacron mesh, which is placed on the
brainstem. Receiver/stimulator has a removable magnet
so that MRI can be safely performed in such cases if need
arises.
ABIs help in communication, awareness and recognition of environmental sounds; however, they are not as
efficient as multichannel cochlear implants. Only limited
numbers of such implants have been performed in the
world and are under constant technological developments.
C. ASSISTIVE DEVICES
Hearing-impaired persons should enjoy life as best as normally hearing persons do. For this, devices are needed to
help him to listen in special difficult situations, warn him
of danger signals and help him to telecommunicate with
his family and friends who are far away from him. These
devices can thus be divided into three groups:
1. Assistive Listening Devices and Systems
They are not hearing aids but devices which help the
hearing impaired to listen efficiently in the presence of
background noise, over the telephone, in auditoriums or
theatres. They may be used by the person individually or
are meant for a group.
According to the technology used, they are grouped as
hard-wired system, induction loops, AM (amplitude modulation), FM (frequency modulation) or infrared signals.
2. Alerting Devices
A hearing-impaired person may not hear a telephone or a
doorbell, a baby crying in another room, an alarm clock
or the noise of a smoke detector. Alerting devices are useful in such situations. They produce an extra loud sound
signal or relay the signal to an area closer to the individual. A “hearing dog” is one such simple device. The dog
is trained to bark loudly at the sound of a doorbell or cry
of a baby to alert his master. It is a helpful companion for
the hearing impaired.
For people with severe to profound or total deafness,
even these devices which produce extra loud sound may
not be useful. They need assistive signalling devices where
the sound (as of doorbell, telephone, alarm clock, baby
crying) is changed into a light signal or vibrations. Alarm
clock with flashing lights or those devices which produce
strong vibrations to awaken the individual or even shake
his bed are also available.
3. Telecommunication Devices
A telephone amplifier can be attached to the hand set of
a telephone, residential or public, to amplify the sound.
A telephone coupler is a device that can be connected to
the telephone and the signal produced is picked up by the
hearing aid.
For the profoundly or totally deaf individuals, telecommunication devices for the deaf (TDDs) can be used. They
convert typed message into sounds that can be transmitted over the standard telephone lines, and at the other
end another TDD converts these sound signals back into
typewritten messages. Email and short message services
(SMS) on mobile phones have made life easier for the
hearing impaired.
Closed-caption television decoder can be attached to
television sets to provide them cues to enjoy news, movies and other programmes.
II. TRAINING
A. SPEECH READING
Earlier called lip-reading, it is an integrated process to
understand speech by studying movements of lips, facial
expression, gestures and the probable context of conversation. The skill of speech reading is not only useful for
the totally deaf but also useful for those hearing-impaired
individuals who have high-frequency loss and difficulty
in hearing in noisy surroundings.
B. AUDITORY TRAINING
It enhances listening skill and is used with speech reading. The patient is exposed to various listening situations
with different degrees of difficulty and taught selectively
to concentrate on speech sounds.
Auditory training is useful for those using hearing aids
and cochlear implants.
C. SPEECH CONSERVATION
In sudden, severe or profound hearing loss, the person
loses the ability to monitor his own speech production.
As a result, defects arise in articulation, resonance, pitch
and the volume of voice. Speech conservation aims to
educate such a person to use his tactile and proprioceptive feedback systems to monitor his speech production.
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Chapter 21
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Otalgia (Earache)
Pain in the ear can be due to causes occurring locally in
the ear or referred to it from remote areas.
I. LOCAL CAUSES
1. external ear. Furuncle, impacted wax, otitis externa, otomycosis, myringitis bullosa, herpes zoster and
malignant neoplasms.
2. middle ear. Acute otitis media, eustachian tube obstruction, mastoiditis, extradural abscess, aero-otitis media and carcinoma middle ear.
II. REFERRED CAUSES
As ear receives nerve supply from Vth (auriculotemporal branch), IXth (tympanic branch) and Xth (auricular
branch) cranial nerves; and from C2 (lesser occipital) and
C2 and C3 (greater auricular), pain may be referred from
these remote areas (Figure 21.1).
1. Via Vth cranial nerve
(a) Dental. Caries tooth, apical abscess, impacted mo-
lar, malocclusion and Costen syndrome.
1
(b) Oral cavity. Benign or malignant ulcerative lesions
of oral cavity or tongue.
(c) Temporomandibular joint disorders. Bruxism, osteo-
arthritis, recurrent dislocation and ill-fitting denture.
(d) Sphenopalatine neuralgia.
2. Via IXth cranial nerve
(a) Oropharynx. Acute tonsillitis, peritonsillar abscess,
tonsillectomy. Benign or malignant ulcers of soft
palate, tonsil and its pillars.
(b) Base of tongue. Tuberculosis or malignancy.
(c) Elongated styloid process.
3. Via Xth cranial nerve. Malignancy or ulcerative lesion of vallecula, epiglottis, larynx or laryngopharynx
and oesophagus.
4. Via C2 and C3 spinal nerves. Cervical spondylosis, injuries of cervical spine and caries spine.
III. PSYCHOGENIC CAUSES
When no cause has been discovered, pain may be functional in origin but the patient should be kept under observation with periodic re-evaluation.
Otalgia is a symptom. It is essential to find its cause be-
fore specific treatment can be instituted.
Figure 21.1. Referred causes of otalgia. Pain is referred via CN V (teeth, oral cavity, TM joint, anterior two-thirds of tongue), C
CN IX (tonsil, base of tongue, elongated styloid process) and CN X (vallecula, pyriform fossa or larynx).
(cervical spine),
2,3
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Chapter 22
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Tinnitus
Tinnitus is ringing sound or noise in the ear. The characteristic feature is that the origin of this sound is within the patient. Usually, it is unilateral but may also affect both ears.
It may vary in pitch and loudness and has been variously
described by the patient as roaring, hissing, swishing, rustling or clicking type of noise. Tinnitus is more annoying in
quiet surroundings, particularly at night, when the masking effect of ambient noise from the environment is lost.
TYPES OF TINNITUS
Two types of tinnitus are described:
1. Subjective, which can only be heard by the patient.
2. Objective, which can even be heard by the examiner
with the use of a stethoscope.
CAUSES OF TINNITUS (TABLE 22.1)
Subjective tinnitus may have its origin in the external ear,
middle ear, inner ear, VIIIth nerve or the central nervous
system. Systemic disorders like anaemia, arteriosclerosis,
hypertension and certain drugs may act through the inner
ear or central auditory pathways. In the presence of conductive hearing loss, the patient may hear abnormal noises
in the head during eating, speaking or even respiration.
Objective tinnitus is seen less frequently. Vascular
lesions, e.g. glomus tumour or carotid artery aneurysm
cause swishing tinnitus synchronous with pulse. It can
be temporarily abolished by pressure on the common carotid artery. Venous hum can sometimes be stopped by
pressure on the neck veins.
Tinnitus synchronous with respiration may occur due
to abnormally patent eustachian tube. Palatal myoclonus
produces clicking sound due to clonic contraction of the
muscles of soft palate and can be easily diagnosed. Clonic
contraction of muscles of middle ear (stapedius and tensor tympani) may cause tinnitus which is often difficult
to diagnose.
Sometimes, tinnitus is psychogenic and no cause can
be found in the ear or central nervous system.
Tinnitus should be differentiated from auditory hallu-
cinations in which a person hears voices or other organized sounds like that of music. It is seen in psychiatric
disorders.
TREATMENT OF TINNITUS
Tinnitus is a symptom and not a disease. Where possible,
its cause should be discovered and treated. Sometimes,
even the treatment of cause may not alleviate tinnitus.
TABLE 22.1 CAUSES OF TINNITUS
Subjective Tinnitus Objective Tinnitus
• Otologic
• Impacted wax
• Fluid in middle ear
• Acute otitis media
• Chronic otitis media
• Ménière’s disease
• Presbycusis
• Noise-induced hearing
loss
• Idiopathic sudden SNHL
• Acoustic neuroma
• Metabolic
• Hypothyroidism
• Hyperthyroidism
• Obesity
• Hyperlipidaemia
• Vitamin deficiency
(e.g. B12)
• Neurologic
• Head injury (labyrinthine
concussion)
• Temporal bone fractures
• Whiplash injury
• Multiple sclerosis
• Postmeningitic
• Brain haemorrhage
• Brain infarct
• Cardiovascular
• Hypertension
• Hypotension
• Anaemia
• Cardiac arrhythmias
• Arteriosclerosis
• Pharmacologic
• Certain drugs used by the
patient
• All ototoxic drugs
• Psychogenic
• Anxiety
• Depression
• Vascular
• AV shunts
– Congenital AV
malformations
– Glomus tumour of
middle ear
• Arterial bruit
– Carotid aneurysm
– Carotid stenosis
– Vascular loop pressing
on VIIIth nerve in
internal auditory canal
– High-riding carotid
artery
– Persistent stapedial
artery
• Venous hum
– Dehiscent jugular bulb
• Patulouseustachiantube
• Palatalmyoclonus
• Idiopathicstapedialortensor
tympani myoclonus
• Dental
• ClickingofTMjoint
When no cause is found, management of tinnitus includes:
1. Reassurance and psychotherapy. Many times the patient
has to learn to live with tinnitus.
2. Techniques of relaxation and biofeedback.
3. Sedation and tranquillizers. They may be needed in initial stages till patient has adjusted to the symptom.
4. Masking of tinnitus. Tinnitus is more annoying at bedtime when the surroundings are quite. Use of a fan,
loudly clicking clock or a similar device may mask the
tinnitus and help the patient to go to sleep. Use of a
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