Introduction to neurology lecture data show for 5th year student

1. Introduction to
Neurology
Prof. Mamun Sarhan
Head of Neurology
Department

2. WHAT IS NEUROLOGY?
Neurology is the branch of medicine that
deals with diseases of the nervous system.

3. Major divisions
Central
nervous
system
Nervous
System
Peripheral
nervous
system

4. Intracranial
Intracranial Spinal
Spinal
part
part part
part
1.Cerebrum Spinal cord &
2. Brain stem
Cauda equina
3. Cerebellum

5. Cerebrum
Two cerebral hemispheres
Connected to:
1. each other by corpus
callosum
2. brain stem by cerebral
peduncles

6. EACH CEREBRAL HEMISPHEREDEVIDED
INTO :
four lobes:
1. Frontal
2. Parietal
3. Temporal
4. Occipital

8. Brain stem
Formed of :
Midbrain
Pons
Medulla
Connected to:
1. Cerebral hemisphere
by cerebral peduncles
2. Cerbellum by cerebellar
peduncles

9. Contains:
• CN 3,4 in midbrain
• CN 5,6,7,8 in pons
• CN 9,10,11,12 in medulla

10. Names of cranial nerves
• Ⅰ Olfactory nerve
• Ⅱ Optic nerve
• Ⅲ Oculomotor nerve
• Ⅳ Trochlear nerve
• Ⅴ Trigeminal nerve
• Ⅵ Abducent nerve
• Ⅶ Facial nerve
• Ⅷ Vestibulocochlear
nerve
• Ⅸ Glossopharyngeal
nerve
• Ⅹ Vagus nerve
• Ⅺ Accessory nerve
• Ⅻ Hypoglossal nerve

11. Classification of cranial nerves
• Sensory cranial nerves: contain only afferent (sensory) fibers
– ⅠOlfactory nerve
– ⅡOptic nerve
– Ⅷ Vestibulocochlear nerve
• Motor cranial nerves: contain only efferent (motor) fibers
– Ⅲ Oculomotor nerve
– Ⅳ Trochlear nerve
– ⅥAbducent nerve
– Ⅺ Accessory nerv
– Ⅻ Hypoglossal nerve
• Mixed nerves: contain both sensory and motor fibers---
– ⅤTrigeminal nerve,
– Ⅶ Facial nerve,
– ⅨGlossopharyngeal nerve
– ⅩVagus nerve

12. Sensory cranial nerves
N. Name Function Assessment
Ⅰ Olfactory Smell Examination of
smell
Ⅱ optic Vision Acuity, field &
fundus
Ⅷ Vestibular Equilibrim Caloric and
part rotational chair
Cochlear Hearing Watch test,
part weber test

13. Motor cranial nerves
N. Name Function Assessment
Ⅲ Oculomotor Motor to superior, inferior and Ptosis, pupil, eye
medial recti; inferior oblique & movements &
levator palpebrae superioris squint
Parasympathetic to sphincter
papillae and ciliary muscle
Ⅳ Trochlear Motor to superior oblique Look to opposite
shoulder
Ⅵ Abducent Motor to lateral rectus Lateral eye
movement
Ⅺ Accessory Motor to sternocleidomastoid Elevaton of
and trapezius shoulders and
neck rotation
Ⅻ Hypoglossal Motor to muscles of tongue Tongue
movements

14. Mixed cranial nerves
N. Name Function Assessment
V Trigeminal Muscles of Face sensations &
mastication & power of muscles of
sensations of face mastication
VII Facial Muscles of facial Muscles of facial
expression & taste expression & taste
sensation in ant. 1/3 sensation in ant. 1/3 of
of tongue tongue
X Vagus Sensation and Palatal and pharyngeal
movements of reflexes & movements of
Larynx, pharynx, uvula
thoracic and
abdominal organs
XII Glossopharyng- Taste in post 2/3 of Taste & general
eal tongue & gen. sensation and
sensation pharyngeal reflex

15. Cerebellum
• Behind the brain stem
• Formed of : medline vermis
two cerebellar hemispheres
• Composed of :
outer grey matter and inner
White matter

16. Cerebellar peduncles
MB
Pons C
MO
 Superior peduncle connects cerebellum with midbrain.
 Middle peduncle connects cerebellum with pons.
 Inferior peduncle connects cerebellum with medulla oblongata

17. Hemispheres and vermis
left right
hemisphere hemisphere
vermis
Cerebellar hemispheres are the two bilateral structures.
Vermis is the unpaired midline structure between
the two hemispheres.

18. Spinal cord
• Inside spinal canal
• End at lower border of L1
• The lowest 3 segments = Conus
• The above 4 segments = Epiconus
• Inner grey matter and outer white
matter

19. Cauda equina
• Lumbosacral roots collection fills
the lower part of the spinal canal
bellow L1

20. Cauda equina
Brachial plexus
Lumbosacral plexus
Cervical enlargement
Lumbosacral enlargement

22. Peripheral nervous system
• A.H.Cs
• Roots
• Plexuses
• Peripheral nerves

23. mo
to
r
Upper
co
motor
rte
x
neuron
internal capsule
Medulla
anterior horn cell
Lower
motor
neuron

24. Motor pathway

25. UMNL LMNL
Tone Increased, with Decreased
‘clasp knife’ quality
Clonus Present Absent
Fasciculations Absent Present
Muscle Wasting Absent, but disuse Present (within 2-3
atrophy eventually weeks)
results
Tendon Reflexes Increased. Extensor Decreased or
plantar reflexes. absent. Flexor
plantar reflexes.
Distribution Whole limbs, with Specific muscle
more weakness in groups affected (e.g.
the upper limb in the distribution of
extensors and lower a spinal segment, or
limb flexors just the proximal
muscles, etc.)

26. Thank You!!!