ladidm J. P,~df,.tt. 45 : S86, 197g

FOR GENERAL PRACT/T!ONER8

N E U R O L O G I G E X A M I N A T I O N OF

~RHARBAN SINO,!

New Ddhi

AN INFANT*

TiJe ,eurologic examination of an in- fant is handicapped by lack ofco-operation.

Therefore, emphasis is laid on thorough

observation which is likely to be most infor-

mative and least disturbing. The infant is best examined in a w~rm, well illuminated

room, about 2 hours after a feed when he is

in a state of quiet wakefulne;s ('state'

3 or 4). A definite scheme of examination is

generally not feasible in infants (Paine 1960,

Singh and Ghai 1976).

Skull

The "containers" of the central nervous system should be examined thoroughly and

systematically. Look for shape, size, swelling and symmetry of the skull. The "setting

sun" sign (Fig. l) is suggestive of raised in- tracranial tension with compression of the orbital plate or brain stem irritation. It is

seen in iz~fants with hydrocephalus and

kernicterus. Transient inconsistent rolling

down of the eyes may be seen normally during the first 3 months, especially in pre-

term babies. The bulging, tense, non-

pulsatile fontanelle offe~ direct evidence of

raised intracranial tension in infants. The

sutures may also be widely separated which

can be palpated or evidenced by elicitation

of a cracked-pot sound ~McEwen's sign).

The sign may be normally present during

�9 From the Neonatal Section, All-India Institute of" Medical Sciences, New Delhi~ 110016. Receivtd on June 14, 19"/8.

the first 3 months when the sutures are o p e n , The occipito-frontal circumference ol , h -p

skull should be measured with a steel *at~l

and compared with the chest circumference"

or the crown-rump length. The head size at,

birth may be more than 3 cm bigger than the latter in babies with prematurity, intra. uterine growth retardation and hydro-

cephalus Trlinsilluminatlon. ol tl~e skuttl must be carrted out tn every inlant with t.~a~

large head. A torch with a stronl~ ii2htj

should be fitted with a rubber adapter ~t,.

ensure close-fitting contact with the skuh

surface. Normally the halo of light extends up to I cm beyond the torch contact point over the occipital region and up ' to 2 cm

over the frontal areas. In infants with

hydrocephaly, the whole skull glows with light. I.ocalised excessive ,ransillumination is seen in association ~ith porencephaly and

cortical thinning while transillumination is

lost over the site of a subdural haematoma.

Spirit Look for spina bifida and neural tube

defects. Thoracolumbar midline dermal

tracks may be associated with recurrent bacterial meningitis. A tuft of hair or swell- ing over the sacral region should alert one

to the possibilities of spina bifida, dias-

tometamye]ia and spinal lipoma.

Cranial .Nerves 1. I I I , IV and VI.

Ptosis, size and symmetry of pupils, doll's eye movements.

I INOH~NEUROLOGIO EXAMtNATION OF AN INFANT 387

2. V and VII Asymmetry of face on crying, wide palpebral fissure, glabeUar tap, rooting reftex and corneal reflex.

$. IX and X Nasal regurgitation and gag reflex

r XI I Asymmetry of tongue, atrophy and fasclculations.

Fuadas The disc is normally pale during in-

fancy and should not be mistakenly diag- nosed as optic atrophy. Papilloedema is un- common because rising intracranial tension is buffered by opening up of the sutures. It

.may occur in cas e ,the sutures a r e prema- ,turely fused or when there is sudden and acute rL~e in intracranial tension. Retinas haemorrhage m a y be seen in normal pre- term infants at birth. The diagnosis of trau- matic subdural haematoma in infancy may be aided b y the presence of retinal haemor- rhages.: Ev;.dence of chorio-retinitis should be looked for when intra-uterine infection is suspected.

Slmid senus 1. Vision. The integrity of the occipital

lobe can be ameued by elicitatloraof the

following responses. A positive response r~les out any damage to the occipital cortex while a negative response demands recessing.

(a) Pupils, Size, symmetry al~d response to light.

(b) Blink response to bright light. (c) Visual attention

[. Takes notice of moving red ball II. Turns towards diffuse light. I I I . Follows light (4-6 weeks) IV. Social smile (4-6 weeks)

2. Hearing. Look for d~e followlng re'--

ponies aRer an appropriate sound stimulus. Startle, blinkln]~, sudden change in acti- vity or heart rate, turns towards source of sound (12 weeks).�9

Molor ~yaem The head must be maintained in the

midline while assessing tone became the tonic neck reflex may cause inequality o f tone on the two sides. The norma'l, term

baby is hyperflexed by adult standardp. Look for posture, symmetry and range of spontaneous movements. Tone is amezsed by posture, resistance to passive .-movements and limb recoil. The child should b e ob- served in different postures e.g. prone, supine, ventral and vertical tuspensim.

Tendon jerks are difbcult to elicit dur- ing the first 3 months due to excessivetone and lack of relaxation. They are normally brisk and there is overflow of knee jerks to cause adductor spasm of both thighs. During the Rrst month, I0-12 umustained beats of ankle clonus are normal. A positive Babinski is of no significance during infancy unless it is asymmetric or if there is marked extension of the big toe with wide fanning of the other toes.

Automasic rtflexes A large number of primitive reflexes

can be elicited during the first 3 months of life (Prechtl and Beintema 19fi4). I t is unnecessary to try and elicit all of these.

The clinically uselul automatic refl, x~-~ are shown in Figs. 5-6. The persistence of these reflexes beyond a certain age is suggestive of cerebral damage {Paine and Oppe 1968).

Sensations It is difficult to ascertain precise sensory

3 8 8 INDIAN JOURNAL OF PI~DIATIUC$

integrity among infants. Following a pin prick, withdrawal response, facial expres- sion or cry should be looked for. The enal reflex must be looked for in infants with neural tube defects.

Developmental examination The neurologic examination of an In-

fant is not complete unless his development is assessed. Infants with diffuse cerebral dys func t i ona re likely to show develop- mental retardation. Table 1 outlines the salient developmental milestones of clinical utility during the first year of life. Infants with hydrocephalus may have considerable delay in holding the head in the absence of

global developmental retardation.

Table 1. S~alient d#gelopmenlal milestones during the first year.

1. Social smile, taking notice of mother, follows light : 2 months.

2. Prone position Turns head to one side Birth Lifts head off cot I month Rolls to supine 3-4 months Pushes chest on arms 4 months

3. Supine pesition Rolls to prone 5 months

4. �9 Vertical position Head control 3-4 months

.

.

Sitting With support 5 months Without support 6-g months Sits up from supine 9 months

Standing With support 10 months Without support 12 months

VOL. 45, No ~

7. Hand manipulations Looks at his own hands 3 mon~l~ t3pen fists 4 monti~ Holds rattle 4 montl~ Transfer bbjects 6-7 mo:/~ 'Scoop' small objects 7-8 mont~ Thumb-forefinger grasp 8-10 montl~ Releases object on command 10 month Holds cup by handle 9-10 month Claps and rings bell on imitation 10 monthi

8. Speech Disyllabic speech 10 montla Imitates spoken word 12 montla,

Early dialnosis of cerebral #alsy A definitive diagnosis of motor defieal

of cerebral origin is generally not 'possible below 5-6 months of age. Table 2 present,

p. a scheme as an a~d to early recognition of cerebral palsy.

Table 2. Early fiatures ~ ctrcbral palsy 1. Persistence ef automatic reflexes

(a) Retrusion reflex (tongue) beyond 1 month

(b) More reflex 3 months (c) Grasp reflex

Palmar 6 months Flantar 9-10 months

(d) Tonic neck reflex 5 months

2. Evidences of spasticity (a) Clenching of fists beyond 4 months (b) External rotation of hips (c) "Supporting reaction" of legs on

vertical suspension before 6 months 3. Delay in appearance of cortical func-

tions

Social smue, taking notice of mother and following light by 180 ~ if ddayed beyond 2 months.

SlNGH~ NEUROLOOIC EXAMINATION OF AN INFANT ~89

Ro~el"encem

Paine, R ,S , Oppe, T,E. (19e6). In Neurological ~xamlnatio~ of Children. Clinics in D�9 Medicine 20/21. Spastlcs Soci.ty Medical ~dueafion aad informaffon Unit,

Palne, R.8, (1960). Neurologic examlnslion of infants and children. Pedlatr. Clin. Xorth Amer. 7, 471.

Prechfl, N., Beintcma, D. (1065). In Neuro- logical E~,amlnation of the Full Term Newborn Infant. Clinics in Devr Medicine No. 12. The Spastics

$oci*#y Medical Education and Information Unit.

Singb, M,, Ghai, O.P, (1976). In Care of the Newborn, s Puldicatlon, Yew Dllhl,