CNS Examinatio

n Hadeel Khadawardi, teaching assistant at Internal

Medicine Department, Faculty of Medicine, Umm Al-Qura University

CNS examination consists of:

A. High Cortical Function B. Cranial Nerves C. Motor D. Coordination E. Sensory

High Cortical Functions

1. Handedness2. Consciousness3. Orientation4. Memory5. Speech

1.Handedness

• Shake patient hand and ask if he or she Rt. or Lt. handed to assess for the likely dominant hemisphere.

• 94% of people are Rt. handed.

2. Consciousness

Levels of consciousness • Alertness• Lethargy • Obtundation• Stupor• Coma

3. Orientation

• Time

• Place

• Person

4. Memory

• Remote (long) memory: Birthdays,…

• Recent (short) memory: event of the day, …

5. Speech

• Dysphasia: dominant higher center disorder in the use of symbols for communication.

• Dysarthria: difficulty with articulation.• Dysphonia: altered quality of the voice.

Types od dysphasia;

1. Expressive2. Receptive

Cranial Nerves

I. Olfactory Nerve

II. Optic Nerve

a)Visual acuity: Is checked by using Snellen Chart.

b) Visual field:

c) Visual color:Is checked by using Ishihara Charts.

d) Fundoscopy:

e) Light reflex:The afferent of light reflex is by optic nerve and the efferent is by oculomotor nerve.

III, IV, VI. Oculomotor, trochlear & abducent Nerves

a) Inspect the eyes for ptosis, shape and size of pupils.

b)Eye movement; ask the patient to follow your finger in H shape comment on: Failure of eye movement Diplopia Nystagmus

c) Light reflex

d) Accommodation

V. Trigeminal Nerve

a)Motor; (Muscle of mastication)TemporalisMasseter Pterygoids

b) Sensory; Access for fine touch and pin break in the 3 divisions ( ophthalmic, maxillary, mandibular).

c) Corneal reflex;The afferent of corneal reflex is by trigeminal nerve and the efferent is by facial nerve.

d) Jaw reflex;

VII. Facial Nerve

• Inspection Forehead wrinklesAngle of the eyeCorner of the mouthLoss of nasolabial fold Dropping of saliva

• MotorFrontalis muscleOrbicularis oculiBuccinator muscleOrbicularis oris

• SensoryAnterior 2/3 of the tongue.

• Corneal reflex

How would differentiate b/w UMNL & LMNL of

VII nerve?

VIII. Vestibulocochlear Nerve

• Whispering• Rinnes test• Webers test

IX, X. Glossopharyngeal & Vagus Nerves

• Inspection of uvula.• Difficulty of swallowing• Ask the patient to say ‘Ah’• Gag reflex

XI. Accessory Nerve

Trapezius muscleSternomastoid muscle

XII. Hypoglossal Nerve

Inspect the tongueAsk the patient to protrude his/her tongue

Motor

Motor

Exposure & InspectionTonePowerReflex

Inspection

• Skin (rash, scar, ulcer,…)• Muscle (wasting, fasciculation)• Deformity• Abnormal movement

Drift (For Upper Limb Only)

Tone

• For upper & lower limbs• Examine each joint• Start from distal to proximal • Always compare both sides

What are the types

of hypertonia

?

Power

• For upper & lower limbs• Examine each joint • Always compare both

sides

What are the

grading of

power?

Reflex

• Patient should be comfortable and relaxed

• Expose the tested muscle• Strike the tendon, not the muscle

belly• Observe the muscle contraction • Reflex of upper limb: Brachioradialis reflex (C5,C6) Biceps reflex (C5,C6) Triceps reflex (C7,C8)• Reflex of lower limb: Ankle reflex (S1,S2) Knee reflex (L3,L4) Planter reflex (S1,S2)• Clonus: Ankle clonus Knee clonus

What are the

grading of

reflex?

What is reinforcem

ent?

Coordination

1)Finger nose test

2)Rapidly alternative movement

3)Heel to shin test

4)Rebound

Gait • Expose both legs

• Ask the patient to: walk heel to toe walk on toes walk on heels squat to stand

• Romberg test

How to differentiate b/w UMNL

&LMNL ?

What are the types of

abnormal gait?

Thank You