Examination of vestibular
system in Infants / children
Balasubramanian M.S. D.L.O.
of vestibular system in an infant or child is an ardous task.
Adding to the obvious difficulties in clinical examination the
child could be apprehensive and non co operative. In infants
the process of examination could be very exacting.
Vestibular dysfinction in children can present in a variety of ways
ranging from a slight delay in acquiring head and postural control
to acute episodes of vertigo and loss of balance. Since there
is a close interaction between the vestibular, visual,
proprioceptive, cerebellar and motor pathways in the
maintenance of postural control and equilibrium in space it
is very difficult to single out one faulty system as a reason
for the defect.
taking: A good history is a must before the actual
examination of a dizzy child. It should concentrate on
developmental milestones, history of drug intake.
a. Intra uterine
infections like toxoplasmosis, rubella
b. Rh incompatibility
c. Ingestion of
e. Toxemia of
c. Respiratory distress
d. CNS infections,
standing, walking and speech
4. History of otitis,
mastoiditis, head injury, CNS
Points to remember
regarding development of inner ear:
1. Vestibular receptors
are fully active and developed by 32 weeks of gestation.
Hence Moro reflex can be theoretically elicited from this
period till the child is 3 - 5 months of age.
of vestibular nerve fibers begins at about 16 weeks of gestation and
is virtually complete at the time of birth
examination of a dizzy child, they are divided into 4 groups
according to their age and levels of maturation of the central
nervous system. They are:
Group I: Children under
the age of 4 months are grouped here. In this group the
tonic neck reflexes predominate. These reflexes can be
demonstrated by passive or active motions of the head relative to
the position of the body. This reflex is due to movement of
endolymphatic fluid through the semiciruclar canals. These
tonic neck reflexes are dependent on the integrity of
vestibular and proprioceptive systems.
righting: In this test active / passive rotation of head from
the midline to one side when the infant is lying supine
will cause a rotation of the whole body in the
direction of head turn.
showing the neck righting reflex test being
Asymmetric tonic neck reflex: This reflex is
obtained with the baby lying supine with the head in midline
position. Active or passive rotation of the head to one side
while the infant's chest is restrained will produce flexion of the
arms and legs on the side of the occiput with extension of arms and
legs on the opposite side.
Figure showing asymmetric tonic neck
Symmetric tonic neck reflex: This reflex has two
stages. In the fist stage, the baby is held in a horizontal
prone position with the baby's chest in the examiner's arm or with
the baby's chest on the examiner's lap. Dorsiflexion of the
head will produce extension of the upper extremities and flexion of
In the second stage,
abrupt ventroflexion of the head will produce flexion of the upper
extremities and extension of lower extremities.
symmetric tonic neck reflex
Moro reflex: For testing the moro
reflex the baby is made to lie in the supine position with the head
ventroflexed and supported by the examiners hand. Now the head
is abruptly dorsiflexed about 30 degrees in relation to the
trunk. This movement will produce an extension and abduction
of the arms, followed by an embrace. This reflex is otherwise
known as startle reflex.
Figure showing Moro reflex.
neck reflexes can be absent in the following situations:
Complete absence of labyrinthine control
2. In severely
asphyxiated hypotonic child with severe central nervous system
3. Severe myopathic disorders
acceleration: In this test the baby is held in a supine
position on the examiner's extended forearms. The head and
trunk must be aligned and parallel to the ground. A rapid
downward acceleration is produced to the baby's horizontal body by
the examiner, who bends on his / her knees to a crouched
position. A normal reflex response consists of abduction and
extension of the arms with fanning of the hands. This response
is similar to that of startle reflex (Moro's reflex). The only
difference being the absence orf dorsiflexion of the head, which
eliminates proprioceptive input from the cervical vertebrae.
Since the stimulus is vertical acceleration, it most probably
stimualtes the maculae of the utricle, as opposed to the cristae of
the semicircular canals that are stimulated with the Moro
Figure showing vertical acceleration being
Doll's Eye phenomenon: In testing for
dolls eye phenomenon, the baby is held vertically under the armpits,
with the head held 30 degrees forwards over the chest and is rotated
for 360 degrees around an axis passing through the examiners
head. Ten rotations in one direction are sufficient and
provides a strong vestibular stimulus. The normal response is
deviation of the eyes and head opposite to the direction of
rotation. This phenomenon is present for first 2 weeks of life
in full term neonates. Premature babies may have persistent
dolls eye movement until 3 months of age. Gradually, the
vestibular responses mature, nystagmus is superimposed, with a quick
component in the direction of rotation.
Doll's eye movement being elicited
Group II: Babies of
this group belong to the age group of 4 - 6 months. Babies in
this age group vary in their developmental achievements. Many
normal infants still have residual primitive tonic neck reflexes,
while in others, righting responses will appear. Both these
conditions are normal.
III: Babies of this group belong to
6 - 18 months. This is a period of rapid motor and sensory
development. The pyramidal tract becomes myelinated.
Integration of visual, labyrinthine and proprioceptive stimuli
occurs during this phase. Righting reflexes are elicited by an
abrupt tilt of the patient to change the patient's centre of
gravity. Since the optical and vestibular righting
responses are identical the baby must be tested blind folded in
order to eliminate visual cues. The most important of the
righting reflexes is the head righting response. This can be
obtained by picking up the infant from prone / supine position and
bringing it to upright position by tilting the infant sideways,
forwards or backwards. Every abrupt change of the head
position in space will elicit vestibular head righting
response. At the same time propping reactions of the
extremities may be seen.
showing righting reflex
Parachute reflex: This is
also known as sentinel reaction. This is a basic protective
body mechanism present throughout life. To test this reflex
the baby is held under his / her arm pits with the back towards the
examiner. The child is suddenly brought vertically down.
The normal response consists of extension and abduction of arms,
with extension of fingers as well as righting response of the
Hopping reaction: This reaction appears in normal
full term infant by 8 - 10 months of age. The baby is tested
in the standing position, with the examiner holding him or her
around the chest and gently tilting him / her sideways, forwards or
backwards. The general response is initiation of a few steps
in the direction of the tilt, accompanied by righting of the
head. Aquiring of this reflex is a preparatory step to
Equilibrium responses: These responses are
more sophisticated and highly integrated righting reactions
involving the whole of the body. This response can be tested
in the sitting or kneeling position, with the examiner pulling the
child by his or her arms sideways. The normal response
consists of righting of the head and extension with abduction of the
extremities on the side opposite to the direction of the tilt.
Electronystagmography: is a method of recording
eye movemnts elicited by positional testing or during labyrinthine
stimulation by rotation or caloric irrigation. This test is
performed in a partially darkened room with the patient blind folded
to eliminate fixation of gaze or optokinetic nystagmus.
Microelectrodes are applied bitemporally for recording eye
movements, and a neutral electrode is applied to the nasion. A
position test is performed with the infant in supine, right lateral
and left lateral positions. In older child a position test is
also done in a sitting position.
Perotatory stimulus can be provided by commercially available
torsion swing. Two perotatory stimulations are usually
recorded with a five minute interval between two stimulations.
The response obtained is a summation of responses elicited from both
infants and children, the values for the speed of the slow
component, amplitude and number of beats per torsion swing are
identical for both right and left beating nystagmus. The total
number of beats of nystagmus to the right and left are also
identical. Directional preponderance is considered when the
total number of beats in one direction exceeds by 25 percent the
number of beats in the other direction. When directional
preponderance is persent it suggests vestibular dysfunction.
Ice - Cold caloric irrigation: Intra canalicular
irrigation of cold water which is about 7 degrees less than that of
body temperature stimulates the lateral canal. This test is
ideally performed with the baby blind folded, in the supine
position, with the head ventroflexed at 30 degrees. The child
is also restrained. A ten second irrigation is a must for
adequate stimulus. Recording should start immediatly after the
onset of irrigation. If the child is sleepy or irritable
during the test the response may not be accurate.
This test is a rather crude way of testing vestibular response to a
stimulus. This test is hence performed only in cases of
extreme doubts regarding the function of vestibular
There is a maturation pattern in the development of
caloric evoked nystagmus response. The amplitude and the
number of beats increase in the first three months of life.
The intensity of the nystagmus is directly proportional to the
gestational age and the weight at birth. The latency of the
response decreases with the gestational age and increasing
Optokinetic nystagmus can be evaluated in most children within three
to six months of birth. As the child grows older, they learn
to pay more attention to the moving images and better responses can
be obtained in them. This nystagmus can be recorded in
response to two speeds of rotation i.e. 3 degrees and 16 degrees per
second. The frequency, amplitude and speed of the slow
component can be analysed in response to the two rotational
speeds. The information obtained is helpful in the evaluation
of overall quality of neurovestibular function.
Bithermal caloric testing: This test involves
irrigation of the external canal for 30 seconds with water at 30
degrees and 44 degrees centigrade. A 10 minute interval is
allowed between irrigations. This test is performed only in
children aged 4 and older. The intensity of nystagmus
represented by the speed of the slow component at the end point of
nystagmus is used for calculations. It takes about 45 minutes
for the procedure to be complete. Children younger than 4
years may not co operate this long.
is used to calculate directional
(R) 30 degrees + (R) 44 degrees - (L) 30 degrees + (L) 44
(R) 30 degrees + (R) 44 degrees
+ (L) 30 degrees + (L) 44 degrees
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