Exam 2 week 6 ppt 7 & 8 Blood Supply and Vascular disorders of brainstem structures

Question 1

name the arteries in the picture of an overall veiw the the vascular supply to the brainstem

Answer 1

1. Anterior spinal artery
2. Posterior spinal artery
3. Vertebral Artery
4. Posterior inferior cerebellar artery
5. Basilar artery
6. Anterior inferior cerebellar artery
7. Circumferential artery
8. Superior cerebellar artery
9. Posterior cerebral artery

Question 2

Explain the vertebrobasilar system: purpose and path

Answer 2

The brainstem is supplied with blood via the Vertebrobasilar system.
•Vertebrobasilar system

• –Vertebral arteries arise from subclavian arteries
• –Rise thru transverse foramina of cervical vertebrae to enter skull thru foramen magnum
• –Run along ventral brainstem to form single basilar artery at caudal pons

The brainstem is supplied with blood via the Vertebrobasilar system. Vertebral arteries arise from subclavian arteries and Rise thru transverse foramina of cervical vertebrae to enter skull thru foramen magnum. The vertebral arteries then run along ventral medulla to form single basilar artery at caudal pons

Question 3

Anterior and posterior spinal arteries

arise from what?

anterior spinal arteriy supplies what?

anterior spinal artery exits the cranium where and why?

Answer 3

Branches from the vertebral arteries

The anterior spinal artery supplies the medial medulla

The anterior spinal artery exits out through the foramen magnum to supply blood to the spinal cord

Question 4

Posterioir inferior cerebellar arteries

abbreviation

where it arises

what does it supply?

Answer 4

PICAs

Paired branches off the vertebral artery

supplies blood to

• the cerebellum
• lateral medulla

Question 5

Another name for Lateral Medullary Syndrome

Answer 5

Wallenberg’s Syndrome

Question 6

Describe Lateral Medullary Syndrome

cause

structures damaged

Answer 6

• •Caused by occlusion of PICA or vertebral artery near PICA
• •Structures damaged include
  
  • –Spinothalamic tract & Spinal nucleus & tract of V
  • –CN VIII, IX, X & XI nuclei
  • –Sympathetic descending tracts

Question 7

Lateral Medullary Syndrome

Symptoms of damage to spino-thalamic tract & nucleus & tract of V

Answer 7

• Impaired pain and temperature sensibility over ipsilateral face and contralateral body

Symptoms of Lateral Medullary Syndrome (Wallenberg’s Syndrome) as the result of damage to the spino-thalamic tract & nucleus & tract of V are Impaired pain and temperature sensibility over ipsilateral face and contralateral body. Remember the spinothalamic tract has decussated but the trigeminal afferents have not

Question 8

Lateral Medullary Syndrome

Symptoms of damage to vestibular nuclei

Answer 8

Symptoms of Lateral Medullary Syndrome (Wallenberg’s Syndrome) as the result of damage to the vestibular nuclei include

• §Nystagmus – involuntary movement of eyes
• §Diplopia – double vision
• §Vertigo – dizziness
• §Ipsiversive lateral pulsion (gait deviation of turning to the same side of the lesion)

Question 9

Lateral Medullary Syndrome

Symptoms of damage to nuclei of CN IX & X (4)

Answer 9

Symptoms of Lateral Medullary Syndrome (Wallenberg’s Syndrome) as the result of damage to nuclei of CN IX & X include:

1. Dysarthria
2. dysphonia
3. Diminished gag reflex
4. Hiccups

Question 10

Lateral Medullary Syndrome

Symptoms of damage to sympathetic tracts (3)

Answer 10

Symptoms of Lateral Medullary Syndrome (Wallenberg’s Syndrome) as the result of damage to sympathetic tracts incude:

• Horner’s syndrome which is
  
  • Miosis (constricted pupil)
  • Ptosis
  • Anhydrosis (no sweating)

Question 11

what is Horner’s syndrome? (with 3 symptoms)

Answer 11

damage to sympathetic tracts

Symptoms include:

• Miosis (constricted pupil)
• Ptosis
• Anhydrosis (no sweating)

Question 12

Alternate name for Medial Medullary Syndrome

Answer 12

•alternating hypoglossal hemiplegia

Question 13

Medial Medullary Syndrome:

Causes

Structures damaged (3)

Answer 13

• •Caused by occlusion of anterior spinal artery
• •Structures damaged
  
  • –Medial lemniscus
  • –medullary pyramid
  • –Nucleus for CN XII

Medial Medullary syndrome (Also called alternating hypoglossal hemiplegia) occurs when there is occlusion of anterior spinal artery (illustrated as B in this picture)

Structures damaged include:

Medial lemniscus

medullary pyramid

Nucleus for CN XII

Question 14

Medial Medullary Syndrome

Symptoms of damage to Medial lemniscus

Answer 14

–contralateral loss of discriminative touch and kinesthesia

Question 15

Medial Medullary Syndrome

Symptoms of damage to pyramids

Answer 15

–contralateral spastic hemiparesis

Question 16

Medial Medullary Syndrome

Symptoms of damage to CN XII Nucleus

Answer 16

Symptoms of Medial Medullary Syndrome as the result of damage to the CN XII Nucleus is atrophy of ipsilateral tongue and tongue deviation to the side of occulsion when protruded

Question 17

List four branches of the basilar artery

Answer 17

1. –Anterior inferior cerebellar arteries (AICAs)
2. –Superior cerebellar arteries (SCAs)
3. –Paramedian (pontine)branches
4. –Posterior cerebral arteries (PCAs)

Question 18

AICAs

Answer 18

Anterior inferior cerebellar arteries

Question 19

SCAs

Answer 19

Superior cerebellar arteries

Question 20

PCAs

Answer 20

Posterior cerebral arteries

Question 21

The Pons is nourished by branches of the ________ artery

Answer 21

The Pons nourished by branches of the basilar artery

Question 22

Syndromes which result in damage to artery branches that nourish the pons include: (4)

(infarcts of the pons)

Answer 22

1. –Medial (paramedian) inferior pontine syndrome
2. –Lateral superior pontine syndrome
3. –Complete basilar syndrome
4. –Locked-in syndrome

Question 23

another name for Medial inferior pontine syndrome

Answer 23

•paramedian inferior pontine syndrome

Question 24

Medial Inferior Pontine Syndrome:

cause

damages what? (5)

Answer 24

(an infarct of the Pons)

Caused by Occulsion of paramedian (pontine) artery branches of basilar artery

1. –Damages CN VI nerve fibers –
   
   • results in ipsilateral medial eye deviation due to paralysis of the lateral rectus
2. –Corticospinal & corticobulbar tracts –
   
   • spastic paralysis of contralateral face & body
3. –Medial lemniscus –
   
   • contralateral loss of discriminative touch and kinesthesia
4. –Paramedian pontine reticular formation –
   
   • ipsilateral horizontal gaze palsy
5. –Pontine nuclei & pontocerebellar fibers –
   
   • limb & gait ataxia

Question 25

Medial Inferior Pontine Syndrome: Symptoms of damage to CN VI nerve fibers

Answer 25

## Footnote results in ipsilateral medial eye deviation due to paralysis of the lateral rectus

Question 26

Medial Inferior Pontine Syndrome: Symptoms of damage to Corticospinal & corticobulbar tracts

Answer 26

spastic paralysis of contralateral face & body

Question 27

Medial Inferior Pontine Syndrome: Symptoms of damage to Medial lemniscus

Answer 27

contralateral loss of discriminative touch and kinesthesia

Question 28

Medial Inferior Pontine Syndrome: Symptoms of damage to Paramedian pontine reticular formation

Answer 28

ipsilateral horizontal gaze palsy

Question 29

Medial Inferior Pontine Syndrome: Symptoms of damage to Pontine nuclei & pontocerebellar fibers

Answer 29

limb & gait ataxia

Question 30

Lateral Superior Pontine Syndrome cause what it damages (4)

Answer 30

(infarct of the pons) –Caused by superior cerebellar artery occlusion 1. –Damage to Superior cerebellar peduncle – * resulting in ipsilateral limb & gait ataxia & intention tremor 2. –Spinothalamic & trigeminothalamic tracts – * contralateral face & body loss of pain & temperature 3. –Medial lemniscus – * contralateral loss of discriminative touch and kinesthesia 4. –Sympathetic tracts – * ipsilateral Horner’s syndrome

Question 31

Lateral Superior Pontine Syndrome: Symptoms of damage to Superior cerebellar peduncle

Answer 31

resulting in ipsilateral limb & gait ataxia & intention tremor

Question 32

Lateral Superior Pontine Syndrome: Symptoms of damage to the Spinothalamic & trigeminothalamic tracts

Answer 32

contralateral face & body loss of pain & temperature

Question 33

Lateral Superior Pontine Syndrome: Symptoms of damage to the Medial lemniscus

Answer 33

contralateral loss of discriminative touch and kinesthesia

Question 34

Lateral Superior Pontine Syndrome: Symptoms of damage to the Sympathetic tracts

Answer 34

ipsilateral Horner’s syndrome: * Miosis (constricted pupil), * Ptosis and * Anhydrosis

Question 35

Complete basilar syndrome cause produces s/s

Answer 35

(infarct of the pons) * caused by lack of lack of blood flow through both paramedian & circumferential (cerebellar) arteries * produces Complete transection of pons * –Signs & symptoms * Coma & paralysis * Pinpoint, unequal pupils

Question 36

Locked In Syndrome cause structurea damaged s/s

Answer 36

(Infart of the Pons) * –May follow occlusion of the basilar artery but infarct confined to the ventral pons * –spares ascending somatosensory pathways and ascending reticular activating system (ARAS) * •Structures damaged include * bilateral corticobulbar and * corticospinal tracts * signs & symptoms * •Fully conscious, but locked-in with near total paralysis * •Inexpressible – only vertical eye movements remain Locked-In Syndrome May follow occlusion of the basilar artery but infarct confined to the ventral pons and spares ascending somatosensory pathways (medial lemniscus & anterolateral systems) and ascending reticular activating system (ARAS). Locked in syndrome produces damaged bilateral corticobulbar and corticospinal tracts. But with intact ARAS the person is fully conscious, but locked-in with near total paralysis. Only inexpressive vertical eye movements remain. Imagine the horror of being able to perceive everything, be cognitively alert but be totally paralyzed and unable to communicate with the outside.

Question 37

Alternate name for Weber's Syndrome

Answer 37

Superior alternating hemiplegia

Question 38

Weber's Syndrome cause structure damaged

Answer 38

(infarct of the midbrain) * –Caused by infarction of paramedian PCA branches in midbrain * –Results in damage to: * Cerebral peduncle (contains corticospinal & corticobulbar tracts) * Oculomotor nerve (CN III) Weber's Syndrome (shown as A in this illustration) and also called superior alternating hemiplegia is Caused by infarction of paramedian PCA branches in midbrain. This condition results in damage to: cerebral peduncle containing the Corticospinal & corticobulbar tracts and the Oculomotor nerve

Question 39

Weber's Syndrome: Symptoms of damage to CN III

Answer 39

* * oculomotor ophthalmoplegia, fixed dilated pupil & ptosis

Question 40

Weber's Syndrome: Symptoms of damage to the Cerebral peduncle

Answer 40

spastic hemiparesis of contralateral body and contralateral lower half of face, tongue & palate

Question 41

Benedikt's Syndrome cause structures damaged (3)

Answer 41

(infarct of the midbrain) * •Caused by occlusion of tegmental branch of the PCA * •Structures damaged * –Nucleus for CN III, * red nucleus & * cerebellothalamic tract Benedikt's Syndrome (B in this illustration) is Caused by occlusion of tegmental branch of the posterior cerebral artery. This results to Damage in the Nucleus for CN III, red nucleus & cerebellothalamic tract

Question 42

Benedikt's Syndrome: Symptoms of damage to CN III nucleus & nerve

Answer 42

Ipsilateral oculomotor palsy – * oculomotor ophthalmoplegia, * fixed dilated pupil & * ptosis

Question 43

Benedikt's Syndrome: Symptoms of damage to the cerebellothalamic tract

Answer 43

Contralateral ataxia of the extremities –

Question 44

Two other symptoms associated with midbrain infarction

Answer 44

1. –Hemiballism * §Damage to basal nuclei (ganglia) connections * §Involuntary, forceful flinging of contralateral limb 2. –Apathetic akinetic mutism * §Damage to periaqueductal gray * §Drowsy, relatively immobile state with arousal only with strong stimuli There are Other symptoms associated with midbrain infarction Hemiballism which is Involuntary, forceful flinging of contralateral limb due to Damage to basal nuclei (ganglia) connections Apathetic akinetic mutism which is a state of consciousness characterized by Drowsy, relatively immobile state with arousal only with strong stimuli due to Damage to periaqueductal gray

Question 45

–Hemiballism: what is it? cause s/s

Answer 45

* a symptom associated with midbrain infarction * Damage to basal nuclei (ganglia) connections * Involuntary, forceful flinging of contralateral limb Hemiballism which is Involuntary, forceful flinging of contralateral limb due to Damage to basal nuclei (ganglia) connections

Question 46

Apathetic akinetic mutism: what is it causes s/s

Answer 46

* symptom associated with midbrain infarction * Damage to periaqueductal gray * Drowsy, relatively immobile state with arousal only with strong stimuli Apathetic akinetic mutism which is a state of consciousness characterized by Drowsy, relatively immobile state with arousal only with strong stimuli due to Damage to periaqueductal gray