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138
Fig. 3.64 Methods of performing Weber’s test
– Rinne’s negative—The air conduction
is less than bone conduction
(AC<BC). This type of nding presents in COHL, MHL individual.
– False Rinne’s negative—Air conduction
is absent, but bone conduction is perceived due to transcranial transmission of
sound to opposite cochlea. This is present
in U/L severe SNHL.
– Weber’s test—This test is proposed by
Ernst Heinrich Weber to assess the
side of lesion.
– Procedure—A vibrating tuning fork is
placed on forehead, or vertex or upper
incisor or dorsum of the nose; now ask
the patient either he hears sound in
centre or one side (Fig.3.64).
– Interpretation
– Centralized—Normal individual, B/L
COHL, B/L SNHL
– Lateralized
– Normal ear—U/L SNHL, U/L MHL
– Better ear—B/L SNHL, B/L MHL
– Disease ear—COHL U/L
– Worse ear—B/L COHL
– Absolute bone conduction—This test
is done to assess the bone conduction
and is also called as modied
Schwabach’s test.
– Procedure—First explain test to
patient; now, a vibrating tuning fork is
placed over the mastoid process of the
patient after occluding the external
auditory canal, and ask the patient
either he hears the sound or not. As
3 History andExamination ofEar
Fig. 3.65 Absolute bone conduction test
soon as the patient indicates that he is
unable to hear the sound anymore, the
tuning fork is transferred to the mastoid process of the examiner after
occluding the external canal to check
either examiner hears the sound or not.
If examiner hears sound, it indicates
that patient’s bone conduction is
reduced; if examiner does not hear
sound, it indicates that patient’s bone
conduction is normal (Fig.3.65).
– Interpretation
– Normal—The bone conduction of
patient is equal to examiner in normal
and COHL.
– Reduced—The bone conduction of
patient is reduced in SNHL and mixed
hearing loss.
– Schwabach’s test—This test is done
to assess the bone conduction, but it
has less sensitivity as compared to
airway, blood circulation (ABC).
– Procedure—A vibrating tuning fork is
placed over the mastoid process. As
soon as the patient indicates that he is
unable to hear the sound anymore, the
tuning fork is transferred to the mas-
toid process of the examiner to check if
the examiner is able to hear the sound
or not (Fig.3.66).
3.2 Examination ofEar
Fig. 3.66 Procedure of
Schwabach’s test
139
– Interpretation
– Normal—The bone conduction is
found normal in COHL.
– Reduced—The bone conduction is
reduced in SNHL and mixed hearing
loss.
– Bing test—This test is proposed by
Albert Bing to examine the effect of
occluding canal on hearing.
– Procedure—The vibrating tuning fork
is placed over the mastoid process
behind the ear while alternately opening and closing the ear canal with a
nger. Ask the patient to report whether
he or she hears a change in loudness or
softness in sound.
– Interpretation
– Positive—Patient with normal and
SNHL hears louder when EAC
occluded.
– Negative—No change when EAC
occluded in COHL.
– Gelle’s test—This is to examine the
effect of increased air pressure in EAC
on hearing.
– Procedure—A vibrating tuning fork is
applied over the mastoid process. If it
is heard, the air in the external auditory
canal is compressed, by means of a
rubber tube inserted into the canal and
a hand bulb, thus pushing the tympanic
membrane, and ossicle medially raises
intralabyrinthine pressure and causes
immobility of basilar membrane, thus
decreasing hearing. There is no effect
on intralabyrinthine pressure in ossicular xation and in ossicular
discontinuity.
– Interpretation
– Positive—Hearing decreases in case
of normal and SNHL.
– Negative—There is no effect on hear-
ing in otosclerosis, ossicular disconti-
nuity, ossicular chain xation.
(h) Hearing assessment of malingerer
• Screening/clinical tests for NOHL or
malingerer
– Erhard’s test: This test is suitable
for detecting total unilateral hearing
loss. It depends on the fact that occlu-
sion of the meatus of normal ear
attenuates speech by 30 dB or less
and does not eliminate speech alto-
gether. The suspected malingerer is
asked to close his eyes and repeat
words heard. He was told that the
normal meatus is being occluded, and
the examiner closes it by pressing the
tragus. Words are then spoken in the
suspected ear; failure to repeat
words indicates malingering since
even with head shadow effect, the
other ear should be able to hear.
– Lombard’s test: This test is based on
the principle that an individual raises
his voice when speaking in a noisy sur-
rounding. The patient is asked to read a
prose, and noise is then applied to the
good ear. If there is organic loss in
the suspected ear, then the voice
140
3 History andExamination ofEar
level is raised; if feigned, there is no
change in speech.
– Hummel’s double-conversation test:
This test depends on confusing effect
of different voices giving different
messages to the two ears. The test is
performed with two speakers each
using separate speaking tube to each
ear. Each speaker asks different questions and tries to confuse the patient. If
one ear is deaf, then the patient
hears only one speaker.
– Teuber’s two-tube test—This test is
similar to the Hummel test. Two tubes
are coupled to each ear. The examiner
stands behind and speaks into either
tube asking the patient to repeat.
Alternate compression of tubes is done
to confuse the patient.
– Coggins stethoscope test: This test is
similar to Teuber’s test; a stethoscope
is used instead of two tubes.
– Callahan’s voice test—The examiner
stands behind the subject. His voice is
delivered to the subject ears via two
separate different lengths of rubber
tubing. In normally hearing subject,
the examiner’s voice appears to come
from the ear coupled to the shorter
tube. If the (R) tube were shorter, it
would be from the (R) ear; however, if
a subject was feigning deafness (R)
side, he would deny hearing anything.
– Swinging story test: In unilateral
hearing loss, a story is presented to
both ears or either ear in parts and
patient is asked to repeat. A subject
feigning deafness would be able to
repeat the complete story without gaps.
– Speech Delayed Auditory
Feedback—Speech is recorded and
then fed at a delay of 0.2s into the suspected ear. A normal person starts stuttering or may not be able to speak.
– Doerer-Stewart test—This test is
performed to confuse the patient by
presenting noise in his ears so that he
loses his yardstick if his intention is to
consistently respond to words above
threshold as though they were at
speech reception threshold.
• Tuning fork test for malingerer
– Stenger’s test—This test is based on
stranger phenomenon. This test can be
done using tuning forks in the clinical
setting. The individual is blindfolded
before the test starts. Two tuning forks
of the same frequency are stricken and
kept at a distance of 25cm from each
ear. When asked, the individual will
claim to hear it in the normal ear. Then,
the tuning fork is brought as close as
8cm near the feigned ear while maintaining the tuning fork at the normal
side at the same distance. The individual will deny hearing anything if he/
she is a malingerer. An individual with
true deafness should continue to hear
the sound on the normal side.
– TEAL test: This technique is used if
someone claims of having conductive
hearing loss. In this test, rst blindfold the
patient and place the tuning fork over
mastoid, then ask either he hears or not. If
he claims of hearing, say you are repeating the test, now place one vibrating tuning fork in front of the ear and next
non-vibrating tuning fork over the mastoid. Malingerer will say he hears the
sound but the genuine one would no.
– LOMBARD test—As stated earlier,
sound of our own voice is necessary
for proper regulation of its tone and
loudness. Barany box is placed in the
patient’s sound ear. The patient is
asked to read the book aloud, and the
Barany box is played on and patient is
asked to continue. If one has profound
hearing loss, he will raise his volume,
but malingerer claiming of unilateral
deafness will continue reading.
– Chimani Moos test—This is actual
modication Weber test in which a
vibrating tuning fork is placed over
vertex; patient says that he hears in
better ear not in deaf ear; now, the
meatus of normal ear is occluded. The
genuine patient will still be able to
3.2 Examination ofEar
141
lateralize the sound to good ear,
whereas a malingerer will deny
hearing the sound at all.
• Clinical tests for vertigo
Tests for vestibulospinal reexes
Tests for cerebellar dysfunction
Tests for vestibulo-ocular reexes
– Tests for vestibulospinal reex—The
vestibulospinal (VS) reexes are
changes in the activity of body muscles
induced by movements of the head in
space that stimulate labyrinthine receptors and aimed at stabilizing posture.
Standing/Romberg test—This is a
clinical test of balance under static
conditions rst described by Moritz
Heinrich von Romberg.
Procedure of Romberg’s test—In
this test, patient is asked to stand
with feet together and arms by the
side with eyes open and then closed.
This test is done to evaluate the
sway when eyes closed compares to
when closed (Fig.3.67).
Results of Romberg’s test
Patient sways to one side (side of
lesion)—peripheral vestibular
lesions.
Patient shows sway side to side or
instability—central vestibular
disorder.
Patient shows no sway or
instability—normal.
Difculty of Romberg’s test (Table
3.53)
Limitations of Romberg’s test
Variations of the Romberg test
Often misunderstood with cerebellar signs.
There is still no standard approach to
applying the Romberg test in clinical
practice.
The criteria for and interpretation of an
abnormal result continue to be debated.
Limited studies are available that dene its
reliability and validity.
Data statistically showing its effectiveness
are not readily available.
Insensitive to compensated vestibular lesions.
Useful in assessment of dorsal column but
not vestibular system.
Cannot distinguish patients with cerebellar
lesions and proprioceptive lesions.
Sometimes cannot identify normal and
patients with peripheral lesions.
Fig. 3.67 Romberg’s test
Romberg tandem or sharpened
Romberg—In this test, the patient
is asked to stand with feet next to
each other and arms are folded on
chest. It is performed rst with open
eyes and then closed eyes (to eliminate the visual cues). The examiner
Table 3.53 Difculty level of regular Romberg’s test
and tandem Romberg’s test
Test Difculty
Eyes-open regular Romberg (EORR) Easy
Eyes-closed regular Romberg (ECRR) Harder
Eyes-open tandem Romberg (EOTR) Harder
Eyes-closed tandem Romberg (ECTR) Very difcult
142
looks for excessive forwardbackward, right-left, or diagonal
sway been. A peripheral vestibular
functional disorder typically causes
ipsilateral falls; on the contrary, upand downbeat nystagmus syndromes are typically associated with
increased body sway forwards and
backwards once the eyes are closed.
One-leg stance test (standing on
one foot at a time)—The partici-
pant must stand unassisted on one
leg and is timed in seconds from the
time one foot is exed off the oor
to the time when it touches the
ground or the standing leg or an arm
leaves the hips. Participants unable
to perform the one-leg stand for at
least 5 s are at increased risk for
injurious fall with the head in a normal (lower left) or with reclining
head (upper right, creates extreme
imbalance). If a psychogenic disorder is suspected, the examiner dis-
Fig. 3.68 Unterberger’s test
tracts the patient by writing numbers
on his arm or having him do maths
mentally. If there is improvement
under the last condition, the stance
disorder has a psychogenic origin.
Unterberger’s test—In this test, the
patient is asked to stand without
stretched hands and eyes closed, then
to walk on spot for a minute, knee
should be raised as high as possible.
This test is named after Siegfried
Unterberger. The purpose of this test
is to identify labyrinthine dysfunction and assess unilateral peripheral
vestibular disturbances (Fig.3.68).
Interpretation of result:
Normal—deviation of up to 45° for
every 50 steps.
Abnormal—deviation of more than
45° for every 50 steps.
Vestibular lesion—deviation
towards the side of lesion.
Central lesion—deviate to variable
directions.
3 History andExamination ofEar
0˚
45˚
Limitations of test:
The value of this test is questionable
in the view of multiplicity of the factors that inuence the response.
Reliability of this test is questionable in case of compensated vestibular dysfunction.
The balance disorder caused by
non-vertigoes causes cannot be differentiated by this test.
This test cannot identify bilateral
lesions.
This test cannot identify central
vestibular pathology.
Gait test—The patient is asked to
walk along a straight line to a xed
point rst with eyes open and then
eyes closed. In uncompensated
lesion of peripheral vestibular system, the patient deviates to the
affected side with eyes closed.
Advantages
This is a very simple and rapid test.
3.2 Examination ofEar
143
Does not require prior preparation
of the subject.
Disadvantage
This test has poor sensitivity and
specicity.
This test cannot identify central
lesion.
This test cannot identify person
with underlying vestibular disorder
when the person is intoxicated.
Types of gait test
Tandem gait test—This is one
where the individual has to walk
heel to toe. Tandem gait has
emerged as a tool in the assessment
of cerebellar disease, Huntington
disease, idiopathic Parkinson’s disease, atypical parkinsonism, peripheral neuropathies and
vestibulopathies.
Incoordination—It is indicative of
ataxia and difculty in motor
movement.
Tinetti gait test—The Tinetti test
was published by Mary Tinetti (Yale
University) to assess the gait and
balance in older adults and to assess
perception of balance and stability
during activities of daily living and
fear of falling. In this test, patient is
to sit in an armless chair and will be
asked to rise up and stay standing.
Now ask the patient to turn 360° and
then sit back down. The several key
points are how does the patient rise
from and sit down on his/her chair,
whether or not the patient stays
upright while sitting and standing,
what happens when the patients’
eyes are closed or when the patient
gets a small push against the sternum. This is to test the patients’ balance. The next step is to ask the
patient to walk a few metres at a
normal speed, followed by turning
and walking back at a ‘fast but safe’
speed. The patient will then sit back
down. There are various parameters
like the length and height of the
steps, the symmetry and continuity
of the steps and straightness of the
trunk to be assessed. During this
test, the patient can use any assistive
devices (walking stick, crutches,
Zimmer frame) they would nor-
mally use. The Tinetti test has a gait
score and a balance score. It uses a
3-point ordinal scale of 0, 1 and 2.
Gait is scored over 12, and balance
is scored over 16 totalling 28. The
lower the score on the Tinetti test,
the higher the risk of falling.
Past nger pointing test—The
patient and examiner face each
other, and patient is instructed to
extend the arms and place the index
nger of one hand on the index nger of the examiner or a static target. Now, the patient is asked to
close eyes, raise arms above head
and quickly return to the previous
starting position. This test id is
given by Barany in 1910. The past
pointing falling and slow component of nystagmus are in the same
direction.
Results
Normal: Finger returns to the starting point with little lateral
deviation.
Abnormal: The patient’s hand will
drift away from the target as the
trunk rotates in peripheral VS
lesion, concussion.
Fukuda stepping test—This test is
used to determine unilateral vestibular system weakness. In this test,
the patient is asked to stepping with
closed eyes and outstretched hands
for 50–100 steps. More than 30
degree of deviation indicates vestibular weakness of the same side
(Fig.3.69).
Babinski-Weil test—The patient is
asked to walk with closed eyes ve
steps forwards and ve steps back-
144
Fig. 3.69 Fukuda stepping test
2
3 History andExamination ofEar
4
6
Fig. 3.70 Babinski-Weil test
wards six times in 30 s. If patient
walked in star-shaped trajectory, it
indicates U/L vestibular lesion
(Fig.3.70).
– Tests for cerebellar dysfunction
Finger nose test—The nger-tonose test measures smooth, coordinated upper extremity movement by
having the examinee touch the tip
of his or her nose with his or her
index nger.
5
3
1
Fig. 3.71 Finger nose test
Procedure—Patient should be
seated or standing, arms abducted
at shoulder to 90°, and elbow exed
to 90°. The examiner places his/her
index nger at various locations in
front of the patient, at a distance
that requires patient to extend their
elbow to reach the target. Now,
patient rst touches examiner’s nger with his index nger and then
his nose and repeats same several
times with the examiner moving
target nger each time. The patient
repeats the process using the opposite hand’s index nger (Fig.3.71).
Results
Finger may initially overshoot target, swinging side to side as it gets
3.2 Examination ofEar
closer and nally reaches its
target—dysmetria.
Tremors when nger gets closer to
its target—intention tremor
Past pointing—dysmetria
Additional testing:
Eyes closed—The examiner holds
nger in one place, while patient
repeats the test above, patient closes
their eyes and repeats the testing
again.
Dysdiadochokinesia—It is demonstrated clinically by asking the
patient to tap the palm of one hand
with the ngers of the other, then
rapidly turn over the ngers and tap
the palm with the back of them,
repeatedly. This movement is
known as a pronation/supination
test of the upper extremity
(Fig.3.72). Inability to perform this
test is due to multiple sclerosis, cerebellar lesion, parkinsonism and
other cerebellar lesions.
Rebound phenomenon (Stewart
Homes)—It is exion of forearm
against the resistance and sudden
release of resistance; in normal person, there is prompt control. In dysmetria, patient will strike his own
head (Fig.3.73).
– Tests for vestibulo-ocular reex—
This is a reex acting to stabilize gaze
during head movement, with eye
movement due to activation of the ves-
Fig. 3.72 Procedure of dysdiadochokinesia
145
Fig. 3.73 Procedure of rebound phenomenon
tibular system. This reex acts to stabilize images on the retinas during head
movement; holding gaze is held
steadily on a location, by producing
eye movements in the direction opposite to head movement. In VOR, the
semicircular canals of the inner ear
measure rotation of the head and provide a signal for the oculomotor nuclei
of the brainstem, which innervate the
eye muscles and produce eye movement opposite to movement of head
that functions to stabilize gaze by
countering movement of the head.
Head thrust test or rapid head
impulse test (Halmagyi-Curthoys
test)
patient’s head is rapidly rotated by
examiner (abruptly and with high
acceleration) about 20 degrees to
right and left. The patient was told
to xate on examiner’s nose. After
the head rotation is stopped, the
examiner watches patient’s eye to
see whether or not a rexation saccade is needed to get the patient’s
eye on examiner nose. A reliable
and signicant rexation saccade is
judged as positive. This test is based
on doll’s eye phenomenon and used
to evaluate vestibulo-ocular reex
in horizontal plane and differentiate
between vertigo and non-vertigo.
146
3 History andExamination ofEar
Result
Patients with unilateral vestibular
weakness will have a catch-up saccade when rotated rapidly to the
side of the lesion.
Complete loss of peripheral vestibular function—positive.
Mild loss indicated by low excitability differences between sides on
the ENG caloric test—negative.
Unilateral hearing loss + positive
head thrust test—acoustic
neuroma.
Chronic peripheral loss—central
compensation that appears within
the rst few days after an acute vestibular insult such as vestibular neuronitis, labyrinthitis or skull base
fractures.
Doll’s head manoeuvre/reex—It
is performed by quickly turning the
patient’s head horizontally from
side to side or vertically up and
down while holding the eyelids
open (Fig.3.74).
Reex is intact/positive—eyes
demonstrate conjugate movement
in the opposite direction of the head
movement.
Reex is absent/negative—the eyes
remain stationary.
Dynamic visual acuity—It can be
done for both vestibular and cervicogenic processes. This test is done
to detect changes in visual acuity
after a vestibular shake-up or a cervical twist. Patients are asked to
read from Snellen’s chart to check
their best baseline visual acuity.
After a head shaking test, that visual
acuity is checked again. If there is
new impairment or dizziness, it is
likely to be due to vestibular dysfunction. On the other hand, if the
visual acuity changes or patient gets
dizzy while the vestibular system is
kept steady by supporting the
patient’s head and then having the
body around the head for a neck torsion test, it is likely to be
cervicogenic.
Positional test—This assessment
subtest is sometimes referred to as
static positional testing performed by
recording eye movements without
visual xation in three cardinal positions: supine, head right and head left.
Direction-xed or changing positional nystagmus is usually peripheral
and an objective sign of vestibular
asymmetry, even if it is present in
only a single head position.
• Clinical examination of eye movements
Nystagmus—This is dened as involuntary
biphasic rhythmic ocular oscillation
which can be either physiological or
pathological.
Pursuit—This is dened as slow and
smooth movement of the eyes to follow
the moving target in the environment.
Saccade—This is dened as rapid jerky
movement of the eyes to bring the image
of the target on to the fovea.
Fig. 3.74 Doll’s head
manoeuvre. (a) Negative
and (b) positive
a b
3.2 Examination ofEar
147
– Nystagmus—It is dened as involun-
tary rhythmic, oscillatory movement of
eyes. Three mechanisms are involved
in maintaining foveal centration of an
object of interest: xation, vestibuloocular reex and the neural integrator.
A disorder affecting any of the three
mechanisms that control eye movements may result in nystagmus.
Traditionally, it is divided into two on
the basis of clinical impression of
waveform, rst is pendular (optokinetic) nystagmus in which eye oscillates with equal speed in both directions
and second is jerk (vestibular)nystagmus
in which one direction is faster than
other and direction of nystagmus is
towards the fast component (towards
the dominant vestibular centre/hyperactive labyrinth). Nystagmus may also
classify like unilateral or bilateral, con-
genital or acquired, conjugate or dis-
conjugate, and physiological or
pathological.
Classication of nystagmus
according to waveform
Jerk (vestibular) nystagmus
Spontaneous nystagmus—This
nystagmus can be upbeat, downbeat, horizontal or mixed and
depending on site of lesion. It may
be peripheral and central. According
to Alexander’s law, the nystagmus
associated with peripheral lesions
becomes more pronounced with
gaze towards the side of the fastbeating component while there is
no change in central nystagmus.
The direction of the fast component
is directed towards the side of gaze.
The nystagmus is divided into
Grade 1 to Grade 3 depending on
severity.
Gaze-evoked nystagmus—Gazeevoked nystagmus is produced by
the attempted maintenance of an
extreme eye position. It is the most
common form of nystagmus
encounter in clinical practice. A
patient recovering from central gaze
palsy shows a phase in which lateral
gaze is possible but cannot be maintained in deviated position. A corrective saccade repositions the eye
eccentrically, and repetition of this
produces nystagmus aptly designated as gaze-paretic nystagmus.
Pendular nystagmus—Pendular
nystagmus is a sinusoidal oscillation and generally does not have a
‘fast phase’ including a saccade, but
is composed entirely of slow eye
movements. This type of nystagmus
can be monocular or binocular and
can differ in both eyes. The waveform of an involuntary eye movement can occur in any direction like
torsional, horizontal, vertical or a
combination of these. It reects
brainstem or cerebellar dysfunction
or both.
Horizontal pendular nystagmus—This is caused by central teg-
mental tract lesion, multiple
sclerosis, congenital, PelizaeusMerzbacher, Zellweger syndrome,
spasmus nutans and Cockayne
syndrome.
Vertical pendular nystagmus—
Pontine haemorrhage, oculopalatine myoclonus, superior canal
dehiscence and toluene snifng.
Torsional pendular nystagmus—
This is caused by oculopalatal
myoclonus, congenital nystagmus.
Elliptical pendular nystagmus—
Sometimes, a horizontal and vertical pendular nystagmus occur
together. They are usually of the
same frequency, but their relative
phase may be different. Depending
on the phase, the eyes may take on
an oblique direction, forming a circle or an ellipse.