CNS examination - Undergraduate level

1. BY
Dr Nadia Shams
Associate Professor
Medicine

2. NERVOUS SYSTEM
 The nervous system consists of
1. The central nervous system (CNS)
2. The peripheral nervous system
3. The autonomic nervous system

3. STEPS OF ASSESSMENT
 History collection
 Physical examination
 Differential diagnosis
 Diagnostic evaluation
 Management Plan

4. HISTORY COLLECTION
 Past history
H/O Fall or trauma that may have involved the
head or spinal cord.
 Family history
Alzheimer’s disease, Epilepsy, Parkinson’s disease,
Spina bifida, etc.
 Personal history
Alcohol, medications and illicit drugs.

5. NEUROLOGICAL ASSESSMENT
 A complete neurological assessment consists of five steps:
Consciousness and Cognition
Cranial nerves assessment
Motor system
Reflexes
Sensory system

6. CONSCIOUSNESS AND COGNITION
ASSESSMENT
 Cerebral abnormalities may cause disturbances in
mental status, intellectual functioning, thought
content and emotional status.
_______________________________________________
 Can you measure or calculate the conscious level ?

8. CRANIAL NERVES ASSESSMENT

9. EQUIPMENTS NEEDED FOR CNS ASSESSMENT
1. Tongue depressor
2. Flash light
3. Sugar and salt samples
4. Watch
5. Cotton – tipped swab
6. Snellens chart
7. Opthalmoscope
8. Samples of familiar odours
9. Tuning fork
10. Knee hammer

10. CRANIAL NERVE I (Olfactory )

11. CRANIAL NERVE II (optic)

12. CRANIAL NERVE III (Occulomotor)

13. CRANIAL NERVE IV (Trochlear)

14. CRANIAL NERVE (Trigeminal)

15. CRANIAL NERVE VI (Abducent)

16. CRANIAL NERVE VII (Facial)

17. CRANIAL NERVE VIII (Acoustic)

18. ROMBERG
TEST

19. CRANIAL NERVE IX
(Glosso-pharyngeal)

20. CRANIAL NERVE X (Vagus)

21. CRANIAL NERVE XI (Spinal accessory)

22. CRANIAL NERVE XII (Hypoglossal)

23. EXAMINING THE MOTOR SYSTEM
 Motor ability
 Muscle strength
 Balance and coordination

24. MOTOR ABILITY
 The patient is instructed to walk across the room, if
possible while the examiner observes posture and
gait. the muscles are inspected and palpated if atrophy
or involuntary movements is noted.

25. Muscle strength
 Ask client to flex muscle and then resist when you apply
opposing force against the muscles
 Compare contralateral sides
 Neck, Trapezius, arms (Biceps, Triceps), wrists, fingers, hips,
legs, ankles and feet

27. Balance and Co-ordination
 Seat the patient. Instruct him to pat his knees with his
hands, palms down then palms up. Have him alternate
palms down and palms up rapidly.
 Watch the patient to notice if his movements are stiff, slow,
non-rhythmic, or jerky.
 The movements should be smooth and rhythmic as he does
the task faster.

28. DEEP TENDON REFLEXES
 Biceps reflex
 Triceps reflex
 Brachioradialis reflex
 Patellar reflex
 Achilles reflex (ankle jerk)

29. BICEPS REFLEX
1- Have the patient's elbow at about a
90° angle of flexion with the arm
slightly bent down as shown in
figure 2-6.
2- Grasp the elbow with your left hand
so the fingers are behind the elbow
and your abducted thumb presses
the biceps brachial tendon.
3- Strike your thumb a series of blows
with the rubber hammer, varying
your thumb pressure with each
blow until the most satisfactory
response is obtained.
4- Normal reflex is elbow flexion
(bending(

30. TRICEPS REFLEX
 Grasp the patient's wrist with
your left hand and pull his
arm across his chest so the
elbow is flexed about 90° and
the forearm is partially bent
down.
 Tap the triceps brachial
tendon directly above the
olecranon process. The
normal response is elbow
extension .
Triceps reflex
Triceps jerk with
one arm flexed
Triceps
jerk with
arms
folded

31. BRACHIORADIALIS REFLEX
 With the patient’s forearm resting on the lap or across
the abdomen, the brachio-radialis reflex is assessed.
 A gentle strike of the hammer 2.5 to 5 cm above the
wrist results in flexion and supination of the forearm.

32. PATELLAR REFLEX
 The patellar reflex is elicited by
striking the patellar tendon just
below the patella. The patient
may be in a sitting or a lying
position.
 If the patient is supine, the
examiner supports the legs to
facilitate relaxation of the
muscles.
 Contraction of the quadriceps
and knee extension are normal
responses.

33. ACHILLES REFLEX
 To elicit an achilles reflex, the foot is dorsi-flexed at
the ankle and the hammer strikes the stretched
achilles tendon. This reflex normally produces
flexion

34. Deep tendon reflexes should be
graded on a scale of 0-4
=0 absent despite of reinforcement
=1 present only with reinforcement
=2 normal
=3 increased but normal
=4 markedly hyperactive, with clonus

35. EXAMINING THE SENSORY SYSTEM
 Tactile sensation
 Superficial pain
 Temperature
 Vibration and position sense

36. DIAGNOSTIC EVALUATION
 Computed Tomography Scanning
 Magnetic Resonance Imaging
 Positron Emission Tomography
 Single photon emission computed tomography
 Cerebral Angiography
 Myelography
 Ultrasound
 Doppler
 EEG
 EMG
 LP

37. Thank You