Stroke Localization - Reynolds

Question 1

____ is going to give lateral, parietal, frontal blood supply. ___ will give frontal and medial. ___ will give ___ cortex and also a big chunk of inferior temporal lobe and thalamus.

Answer 1

MCA is going to give lateral, parietal, frontal blood supply. ACA will give frontal and medial. PCA will give occipital cortex and also a big chunk of inferior temporal lobe and thalamus.

Question 2

A big ___ stroke can make you hemiplegic on one side. __ lacunar stroke can also make you hemiplegic. Which one of these can kill the patient?

The ___ stroke.

Answer 2

A big MCA stroke can make you hemiplegic on one side. A internal capsule lacunar stroke can also make you hemiplegic. The MCA stroke can kill you!

Question 3

Cortical strokes signs:

hemibody symptoms with cortical findings

Caused by ___ vessels, often embolic events (artery-artery or heart –> brain)

• At risk for recurrence if embolic
• At risk for ____, increased ___ and herniation
• Large cortical strokes can be fatal due to brain ___ and mass effect/herniation

•Signs??

_____ abnormalities (aphasias)

• __ preferences
• ___ syndromes
• cortical ___ findings
• Personality changes

Answer 3

Cortical strokes signs:

hemibody symptosm with cortical findings

Caused by large vessels, often embolic events (artery-artery or heart –> brain)

• At risk for recurrence if embolic
• At risk for swelling, increased ICP and herniation
• Large cortical strokes can be fatal due to brain edema and mass effect/herniation

•Signs??

language abnormalities (aphasias)

•gaze preferences

•neglect syndromes

• cortical sensory findings
• Personality changes

Question 4

If you have hemibody weakness or numbess in addition to aphasia, visual loss and personality changes, it is probably a cortical/subcortical lesion?

Answer 4

cortical!

Question 5

A big dominant left ___ stroke will cause sudden onset of right hemiparesis. The arm will be weaker than the leg unless it is really bad, in which case the whole right side can be plegic. Sensory loss of right side (face arm and leg). Dyshphasia will also occur.

The neurological deficit will depend on the extent of the infarct and hemispheric dominance, and include:

____ hemiparesis

____ hemisensory loss

right visual field ____ in both eyes.

_____: if the dominant hemisphere is involved; may be expressive in anterior MCA territory infarction, receptive in posterior MCA stroke, or global with extensive infarction

neglect: non-dominant hemisphere

Answer 5

A big dominant left MCA stroke will cause sudden onset of right hemiparesis. The arm will be weaker than the leg unless it is really bad, in which case the whole right side can be plegic. Sensory loss of right side (face arm and leg). Dyshphasia

The neurological deficit will depend on the extent of the infarct and hemispheric dominance, and include:

contra hemiparesis

contra hemisensory loss

right visual field hemianopia in both eyes.

aphasia: if the dominant hemisphere is involved; may be expressive in anterior MCA territory infarction, receptive in posterior MCA stroke, or global with extensive infarction

Question 6

What type of stroke?

Answer 6

Question 7

Right sided dominant MCA stroke. What would happen?

Answer 7

Motor sensory loss in the left (arm is worse than leg unless it is really bad). Sensory loss, visual field abnormality. Instead of aphasia, you get neglect. Right gaze deviation.

These patients have left side neglect.

Question 8

What is going on?

What would you expect the patient to have?

Answer 8

Right MCA stroke

Left hemi-inattention, left visual field deficit, left hemiparesis (arm > leg), left hemisensory loss, right gaze deviation.

Question 9

Horizontal gaze palsy may be caused by lesions in the cerebral hemispheres, which cause paresis of gaze ___ from the side of the lesion

Answer 9

Horizontal gaze palsy may be caused by lesions in the cerebral hemispheres, which cause paresis of gaze away from the side of the lesion

Question 10

ACA strokes:

• Very ___
• Hemi____ ( leg >> arm and face)
• ____ preference
• Sensory ___( leg > arm/face)
• ____disorders because frontal lobe is affected. Unlike neglect, they know that something is wrong, but because of this disorder, they are difficult to work with in rehab.
• incontinence

Gaze palsy is a term used to indicate a ____ limitation of the movements of both eyes in the same direction (ie, a conjugate ophthalmoplegia). With a cerebral lesion (supranuclear), the term gaze preference denotes an acute inability to produce gaze contralateral to the side of the lesion and is accompanied by a tendency for tonic deviation of the eyes toward the side of the lesion. In such cases, the doll’s head maneuver generates a full range of horizontal eye movements because the infranuclear pathways are intact. Stroke is the most common etiology for this type of cerebral injury. In contrast, brainstem lesions that produce a horizontal gaze palsy disrupt eye movements ____ the side of the lesion (opposite to the pattern seen with lesions of the FEF)

Answer 10

ACA strokes:

• Very uncommon
• Hemiparesis ( leg >> arm and face)

•gaze preference

• Sensory ___( leg > arm/face)
• ____disorders because frontal lobe is affected. Unlike neglect, they know that something is wrong, but because of this disorder, they are difficult to work with in rehab.
• incontinence

Gaze palsy is a term used to indicate a symmetric limitation of the movements of both eyes in the same direction (ie, a conjugate ophthalmoplegia). With a cerebral lesion (supranuclear), the term gaze preference denotes an acute inability to produce gaze contralateral to the side of the lesion and is accompanied by a tendency for tonic deviation of the eyes toward the side of the lesion. In such cases, the doll’s head maneuver generates a full range of horizontal eye movements because the infranuclear pathways are intact. Stroke is the most common etiology for this type of cerebral injury. In contrast, brainstem lesions that produce a horizontal gaze palsy disrupt eye movements toward the side of the lesion (opposite to the pattern seen with lesions of the FEF)

Question 11

What kind of stroke?

Looking at the scan, where do you think they’d be weak?

Answer 11

left ACA

Just by looking at the scan, you can say that the patient’s right side will be weak

Question 12

PCA Syndrome:

Hemi____ (blindness over half the field of vision) or cortical blindness if ___

Visual behavioral disorders

• __ (persistance of a visual image)
• ___ (inability to recognize faces)
• ___ (can’t read)
• color ____

Temporal lobe involvement may cause aphasia and ___ loss

•Thalamic involvement can cause ___ loss

Answer 12

PCA Syndrome:

Hemianopia or cortical blindness if bilateral

Visual behavioral disorders

•palinopsia (persistance of a visual image)

•prosopagnosia (inability to recognize faces)

•alexia (can’t read)

•color anomia

Temporal lobe involvement may cause aphasia and memory loss

•Thalamic involvement can cause sensory loss

Question 13

Cerebellum:

• ____ center of the brain
• Responsible for motor timing
• All output from the cerebellum is ____
• Main motor output:
• Dentate –> Cerebellar Peduncle –> Contralateral Red Nucleus –> Thalamus –> Motor cortex
• This is why a cerebellar lesion causes ____ ataxia
• Cerebellum has emerging role in cognition

Symptoms of a Cerebellar stroke

• Dizziness
• Un___
• Nausea/vomiting
• Double ___
• Difficulty with ___

Answer 13

Cerebellum:

• Coordination center of the brain
• Responsible for motor timing
• All output from the cerebellum is inhibitory

•Main motor output:

• Dentate –> cerebellar Peduncle –> Contralateral Red Nucleus –> Thalamus –> Motor cortex
• This is why a cerebellar lesion causes ipsilateral ataxia
• Cerebellum has emerging role in cognition

Symptoms of a Cerebellar stroke

• Dizziness
• Uncoordination
• Nausea/vomiting
• Double vision
• Difficulty with balance

Question 14

The floculonodular lobe gives direct inputs to the ___ nuclei.

Anywhere in that pathway, from inner ear to vestibular nuclei to cerebellum, can give you vertigo and nausea.

Vertigo and nausea does not tell you that you have a cerebellum problem. If you have veritgo and nausea AND you are uncoordinated, then it would indicate a cerebellum problem.

Inner ear problems can give you vertigo and nausea but it does not make you ___..

Answer 14

The floculonodular lobe gives direct inputs to the vestibular nuclei.

Anywhere in that pathway, from inner ear to vestibular nuclei to cerebellum, can give you vertigo and nausea.

Vertigo and nausea does not tell you that you have a cerebellar problem. If you have veritgo and nausea AND you are uncoordinated, then it would indicate a cerebellum problem.

Inner ear problems can give you vertigo and nausea but it does not make you ___.

Question 15

What is this?

Answer 15

Left cerebellar stroke

Question 16

Small-Vessel Syndromes

• Small, deep infarcts in the distribution of the ____, ____ or ____ branches of the basilar
• ____% of strokes
• Pathology is fibrinoid necrosis, lipohyalinosis and microatheroma
• Risk factors are HTN, DM, tobacco abuse, hyper____
• No ___ findings on exam

Answer 16

Small-Vessel Syndromes

• Small, deep infarcts in the distribution of the lenticulostriates, thalamoperforators or paramedian branches of the basilar
• 25% of strokes
• Pathology is fibrinoid necrosis, lipohyalinosis (lipohyalinosis is a small-vessel disease in the brainand microatheroma)
• Risk factors are HTN, DM, tobacco abuse, hyperlipidemia
• No cortical findings on exam

Question 17

Classic lacunar stroke:

Pure motor hemiparesis: ____ ____ or ventral ___.

Pure sensory: sensory nuclei of ___

Clumsy-hand/dysarthia: ventral ___ or internal capsule (subset of a pure motor stroke)

Sensorimotor: ____ involving motor and sensory nuclei or thalmo-capsular or just a larger subcortical lacune

Ataxic-hemiparesis: usually more frontal in the deep white matter.

Answer 17

Classic lacunar stroke

Pure motor hemiparesis: internal capsule or ventral pons

Pure sensory: sensory nuclei of thalamus

Clumsy-hand dysarthria: ventral pons or internal capsule (subset of a pure motor stroke)

Sensorimotor: thalamus involving motor and sensory nuclei or thalmo-capsular or just a larger subcortical lacune

Ataxic-hemiparesis: usually more frontal in the deep white matter.

Question 18

What happens if you have a lacunar stroke in the medulla vs pons?

Answer 18

If you had a stroke in the pons, you only get pure motor loss. If it happens in the medulla, you will not have facial weakness (facial nerve comes out of the pons)

Question 19

If you get pure sensory loss, where could your lesion be?

Answer 19

Sensory neurons of the thalamus

Question 20

Lacunar Strokes:

1. Pure motor hemiparesis if stroke is in - ___ limb of the internal capsule, basis pontis, corona radiata. It is marked by hemiparesis or hemiplegia that typically affects the __, __ or __ of the ____ side. Dysarthria, dysphagia, and transient sensory symptoms may also be present.
2. Pure sensory stroke - __ ___, internal capsule, corona radiata, midbrain. Marked by persistent or transient numbness, tingling, pain, burning, or another unpleasant sensation on one side of the body.
3. Clumsy-hand, dysarthria syndrome - basis pontis, anterior limb or ___ of internal capsule, corona radiata, basal ganglia, thalamus, cerebral peduncle. The main symptoms are ____ and clumsiness (i.e., weakness) of the hand, which often are most prominent when the patient is ___.
4. Sensorimotor stroke -__ and adjacent ___ internal capsule, lateral pons. This lacunar syndrome involves hemiparesis or hemiplegia with contralateral sensory impairment
5. Ataxic-hemiparesis: usually more frontal in the deep white matter.

Answer 20

Lacunar Strokes:

1. Pure motor hemiparesis - posterior limb of the internal capsule, basis pontis, corona radiata. It is marked by hemiparesis or hemiplegia that typically affects the arms, face or legs of the contralateral side. Dysarthria, dysphagia, and transient sensory symptoms may also be present.
2. Pure sensory stroke - ventral hypothalamus, internal capsule, corona radiata, midbrain. Marked by persistent or transient numbness, tingling, pain, burning, or another unpleasant sensation on one side of the body.
3. Clumsy-hand, dysarthria syndrome - basis pontis, anterior limb or genu of internal capsule, corona radiata, basal ganglia, thalamus, cerebral peduncle. The main symptoms are dysarthia and clumsiness (i.e., weakness) of the hand, which often are most prominent when the patient is writing.
4. Sensorimotor stroke - thalamus and adjacent posterior internal capsule, lateral pons. This lacunar syndrome involves hemiparesis or hemiplegia with contralateral sensory impairment
5. Ataxic-hemiparesis: usually more frontal in the deep white matter.

Question 21

Why can’t a pure sensory stroke not be an MCA stroke?

Answer 21

You can knock out all your sensory pathways by knocking out your sensory cortex. But you need a proximal MCA occlusion to get all the sensory loss.

A pure motor stroke without sensory cannot be an MCA stroke because if you occlude proximal MCA, you knock out everything. (sensory and motor)

Question 22

Any stroke from the ___ ___ all the way up, will give you a contralateral upper motor type facial weakness.

Answer 22

Any stroke from mid pons all the way up, will give you a contralateral upper motor type facial weakness.

Question 23

Answer 23

Question 24

Diplopia with involvement of cranial nerves __ and ___ points to a ___ lesion

Answer 24

•Diplopia with involvement of cranial nerves 3 and 4 points to a midbrain lesion

Question 25

• Pons
• Home of cranial nerves 5,6,7,8
• Horizontal ___ center
• ___ with equal and reactive pupils and horizontal eye movement abnormalities point to a ___ lesion

Answer 25

Pons

• Home of cranial nerves 5,6,7,8
• Horizontal gaze center
• Diplopia with equal and reactive pupils and horizontal eye movement abnormalities point to a pontine lesion

Question 26

• Home of cranial nerves 9,10,11,12
• No eye movement abnormalities except for ____
• Prominent __ and __ may be present with involvement of vestibular nuclei
• Crossed face/body sensory loss
• H___, yawning

What is the lesion?

Answer 26

• Medulla
• Home of cranial nerves 9,10,11,12
• No eye movement abnormalities except for nystagmus
• Prominent vertigo and nausea may be present with involvement of vestibular nuclei
• Crossed face/body sensory loss

•Hiccups, yawning

Medulla!!!

Question 27

If I want to move my eyes to the left, which FEF is activated?

Answer 27

If you want to move your eyes to the left, your RIGHT FEF will be activted.

The right side of your brain will pay attention to the entire left space. Your FEF push your eyes left or right. If I’m gonna look over to the left, my right FEF will make my eyes look right. How do they do this? They send a message down the mesencephalic pathway, crosss over to the opposite side PPRF. The left PPRF is the horizontal gaze activation center. It tells the 3rd and 6th nerves to do something. FEF descends, goes to the opp. PPRF. The PPRP then tells 6th nerve to do their thing!

Question 28

Answer 28

Right gaze preference

Question 29

Left MCA stroke will give you a ___ gaze preference

Answer 29

left

Question 30

Let’s say a patient has a left MCA stroke and you ask them to look to the right. He is able to bring their eyes to midline but then it stops. How did he do this?

Answer 30

Because he consciously shut off the other FEF. But since the left FEF are not working, they can’t tell the right PPRF to move the eyes right.

Question 31

The vestibular nuclei have direct input into the ___. This is why you can turn my head and your eyes stay right on target. When you do a dolls eye (oculo-cephalic reflex) that will activate the vestibular system which will activate the PPRF. If i squirt cold water into the person’s ear, the eyes deviate to the cold water but the nystagmus is to the opposite side.

Answer 31

The vestibular nuclei have direct input into the PPRF. This is why you can turn my head and your eyes stay right on target. When you do a dolls eye (oculo-cephalic reflex) that will activate the vestibular system which will activate the PPRF. If i squirt cold water into the person’s ear, the eyes deviate to the cold water but the nystagmus is to the opposite side.

Question 32

COWS and the dollhead reflex activate the ___. If you have a lesion on the left PPRF, what happens?

Can you overcome this?

Answer 32

PPRF

You have a complete left gaze palsy. PPRF is dead.

You can’t overcome it with a reflex maneuver because the PPRF is not working (responsible for oculo-cephalic reflex)

Question 33

What is going on here?

Where is this path?

Answer 33

Right INO.

Left eye looks to left, but right eye can’t move past midline. This is a pontine-medullary pathway lesion.

Question 34

What is going on here?

The patient ruined their left PPRF and left MLF

Answer 34

1 and a half palsy

Question 35

Medullary Stroke Syndromes:

• Due to embolization to or occlusion of ____ arteries and their branches
• ____ infarcts are relatively common
• 2 Major syndromes

1. Medial Medullary

•__ __ artery

2. Lateral Medullary (Wallenberg)

•Usually caused by __ occlusion

Answer 35

Medullary Stroke Syndromes:

•Due to embolization to or occlusion of vertebral arteries and their branches

•PICA infarcts are relatively common

•2 Major syndromes

1. Medial Medullary

•Anterior Spinal artery

2. Lateral Medullary (Wallenberg)

•Usually PICA

Question 36

____ ___ Syndrome:_

• __ __ Artery
• Uncommon/common stroke syndrome
• Affected structures and resultant deficits include:

1. corticospinal tract

•medullary pyramid Lesions result in contralateral spastic hemiparesis.

2, medial lemniscus

•contralateral loss of tactile and vibration sensation from the trunk and extremities.

3. hypoglossal nucleus or intraaxial root fibers [cranial nerve (CN) XII].

•Lesions result in ipsilateral flaccid hemiparalysis of the tongue

Answer 36

Medial Medullary Syndrome

•Anterior Spinal Artery

•Uncommon stroke syndrome

•Affected structures and resultant deficits include:

1. corticospinal tract

•medullary pyramid Lesions result in contralateral spastic hemiparesis.

2, medial lemniscus

•contralateral loss of tactile and vibration sensation from the trunk and extremities.

3. hypoglossal nucleus or intraaxial root fibers [cranial nerve (CN) XII].

•Lesions result in ipsilateral flaccid hemiparalysis of the tongue

Question 37

Patient comes to your office with contralateral weakness, contralateral vibration and proprioception, ipsilateral tongue deviation, NO pain/temp loss

What could she have?

Answer 37

ASA stroke - medial medullary

Medial medullary: key points are the corticospinal tract is very medial in the medulla. The hypoglossal nucleus and nerve stay medial as well. And the MEDIAL lemniscus is also medial. So, a spinal artery infarct will affect those tracts and spare the more lateral nuclei and tracts.

Question 38

What type of lesion is this?

Crossed Finding Hallmark: face, contralateral pain/temp sensory loss
Horner’s syndrome common
Hiccups are common

1. vestibular nuclei
   Lesions result in
   nystagmus, nausea, vomiting, and vertigo.
2. inferior cerebellar peduncle lesions
   result in ipsilateral cerebellar signs (dystaxia, dysmetria (past-pointing), dysdiadochokinesia].
   A PICA infarct can also affect the ipsilateral cerebellum, also causing the dysmetria
3. nucleus ambiguus of CN IX, CN X, and CN XI.
   Lesions result in
   · ipsilateral laryngeal, pharyngeal, and palatal hemiparalysis
   · i.e., loss of the gag reflex (efferent limb)
   dysphagia
   dysphonia (hoarseness)].
4. glossopharyngeal nerve roots.
   ■ Lesions result in
   loss of the gag reflex (afferent limb).
5. Vagal nerve roots
   Lesions result in
   • same deficits as seen in lesions
   involving the nucleus ambiguus

• 6. Spinothalamic Tracts
• Contralateral loss of pain and temperature
• 7. Trigeminal Nucleus and tract
• Ipsilateral facial sensory loss to pain and temp
• 8. Descending sympathetic tract
• Ispilateral Horner’s syndrome
• Ptosis, miosis and occasionally hemianhidrosis
• Hiccups: Can be a form of myoclonus originating in the medulla.****

Answer 38

_Lateral medullary syndrome or posterior
inferior cerebellar artery (PICA) syndrome_

Crossed Finding Hallmark: face, contralateral pain/temp sensory loss
Horner’s syndrome common
Hiccups are common

1. vestibular nuclei
   Lesions result in
   nystagmus, nausea, vomiting, and vertigo.
2. inferior cerebellar peduncle Lesions
   result in ipsilateral cerebellar signs (dystaxia, dysmetria (past-pointing), dysdiadochokinesia].
   A PICA infarct can also affect the ipsilateral cerebellum, also causing the dysmetria
3. nucleus ambiguus of CN IX, CN X, and CN XI.
   Lesions result in
   · ipsilateral laryngeal, pharyngeal, and palatal hemiparalysis
   · i.e., loss of the gag reflex (efferent limb)
   dysphagia
   dysphonia (hoarseness)].
4. glossopharyngeal nerve roots.
   ■ Lesions result in
   loss of the gag reflex (afferent limb).
5. Vagal nerve roots
   Lesions result in
   • same deficits as seen in lesions
   involving the nucleus ambiguus

• 6. Spinothalamic Tracts
• Contralateral loss of pain and temperature
• 7. Trigeminal Nucleus and tract
• Ipsilateral facial sensory loss to pain and temp
• 8. Descending sympathetic tract
• Ispilateral Horner’s syndrome
• Ptosis, miosis and occasionally hemianhidrosis
• Hiccups: Can be a form of myoclonus originating in the medulla.****

Question 39

Patient has:

• Crossed face-body sensory loss
• Hoarseness and dysphagia
• Ipsilateral Horner’s
• Ipsilateral Ataxia
• NO motor weakness
• Hiccups

What happened?

Answer 39

Lateral medullary stroke

• Crossed face-body sensory loss
• Hoarseness and dysphagia

•Ipsilateral Horner’s

• Ipsilateral Ataxia
• NO motor weakness
• Hiccups

The LATERAL medullary syndrome spares the medial part of the medulla, so NO motor weakness, no tongue deviation and no dorsal column dysfunction. The main areas affected are sensory of Cn 5, spinothalamic tract which already crossed in the spinal cord so effects are contralateral. The lesion will affect either the nucleus ambiguus or fiber tracts of the vagal nerve resulting in ipsilateral hoarsness, dysphagia and palatal weakness. Descending sympathetic tract involvement causes an ipsilateral Horner’s syndrome. Involvement of the vestibular nuclei result in nystagmus, nausea, vomiting and vertigo. Lesion of the cerebellar peduncle cause ipsilateral ataxia because you are affecting outflow from the ipsilateral cerebellum. A larger PICA infarct will also infarct the inferior cerebellum itself. Hiccups are common.

Question 40

Key feature of a Wallenberg infarct are:

Lateral medullary syndrome, (or Wallenberg syndrome) is an acute ischemic infarct due to occlusion of the vessels supplying the lateral medulla oblongata; most commonly occlusion of intracranial portion of the _ __ followed by ___ and it’s branches.

Answer 40

Horner’s syndrome

Contralateral body numbdness

Vertigo

Hoarseness

Ataxia (if you get cerebellar outflow)

You canalso get ataxia from a pica infarct.

Lateral medullary syndrome, (or Wallenberg syndrome) is an acute ischemic infarct due to occlusion of the vessels supplying the lateral medulla oblongata; most commonly occlusion of intracranial portion of the vertebral artery followed by PICA and it’s branches.

Question 41

What syndrome?

Answer 41

Wallenberg syndrome (lateral medullary)

Question 42

What type of syndrome?

Answer 42

Pontine

Question 43

What type of syndrome?

• Usually paramedian branches of the basilar
• Deficits result from midline structures
• 1. Corticospinal tract: contralateral weakness
• 2. Medial lemniscus: contralateral tactile, vibratory loss
• 3. Abducens nerve roots: weakness of ipsilateral eye abduction

*** Purely ventral lesion may only affect CST

•

Answer 43

medial pontine

Remember that a lesion in the pons above the facial nucleus will cause a contralateral, UMN-type facial weakness. There may be NO crossed findings in a purely ventral lesion in the corticospinal tract

Question 44

What type of syndrome? From what kind of infarct?

• 1. Facial Nucleus: ipsilateral LMN facial weakness and loss efferent limb of corneal reflex
• 2. Paramedian pontine reticular formation: ispilateral gaze palzy
• 3. Cochlear nucleus: ipsilateral deafness
• 4. Vestibular nuclei: nausea, vertigo
• 5. Trigeminal nucleus: ipsilateral face numbness
• 6. Middle or inferior cerebellar peduncle: ipsilateral ataxia
• 7. Spinothalamic tracts: contralateral numbness of limbs

Answer 44

Lateral Pontine Syndrome from an AICA infarct

• 1. Facial Nucleus: ipsilateral LMN facial weakness and loss efferent limb of corneal reflex
• 2. Paramedian pontine reticular formation: ispilateral gaze palzy
• 3. Cochlear nucleus: ipsilateral deafness
• 4. Vestibular nuclei: nausea, vertigo
• 5. Trigeminal nucleus: ipsilateral face numbness
• 6. Middle or inferior cerebellar peduncle: ipsilateral ataxia
• 7. Spinothalamic tracts: contralateral numbness of limbs

Question 45

What hapens if you have a complete LMN facial droop on right side, and left sided weakness. What do you have?

Answer 45

It has got to be a right medial pontine stroke.

Question 46

____, ___ ____ Lesion_

• 1.RAS is usually impaired leading to altered consciousness or coma
• 2.Bilateral CST: quadraparesis
• Patient may exhibit decorticate posturing
• 3. Bilateral sympathetic chain = small, pinpoint pupils
• 4. Bilateral PPRF = complete horizontal gaze palsy.
• Patients may have spontaneous ocular bobbing

Answer 46

Bilateral, complete, pontine lesion

• 1.RAS is usually impaired leading to altered consciousness or coma
• 2.Bilateral CST: quadraparesis
• Patient may exhibit decorticate posturing
• 3. Bilateral sympathetic chain = small, pinpoint pupils
• 4. Bilateral PPRF = complete horizontal gaze palsy.
• Patients may have spontaneous ocular bobbing

Question 47

Dorsal Midbrain Syndrome (Parinaud)

• Caused by pressure upon the ___ ___ and ____ area
• Can be tumors, elevated ___
• Paralysis of ___ ___, usually inability to look up
• Loss of ____ response to__
• But retained pupil constriction with convergence
• Convergence-retraction nystagmus upon attempted up-gaze

Answer 47

Dorsal Midbrain Syndrome (Parinaud)

• Caused by pressure upon the superior colliculus and pre-tectal area
• Can be tumors, elevated ICP
• Paralysis of vertical gaze, usually inability to look up
• Loss of pupillary response to light
• But retained pupil constriction with convergence
• Convergence-retraction nystagmus upon attempted up-gaze

Question 48

Ventro-medial midbrain (Weber)

•1. ____ nerve roots: ipsilateral___ nerve palsy

when complete, eye is ___ and deviated

__ and ___

• 2. CST: contralateral hemiparesis
• This will usually include the face, and often the ___ and palate

Answer 48

Ventro-medial midbrain (Weber)

•1. Oculomlotor nerve roots: ipsilateral 3rd nerve palsy

when complete, eye is dilated and deviated

down and out

• 2. CST: contralateral hemiparesis
• This will usually include the face, and often the tongue and palate

Question 49

Paramedian midbrain (Benedikt)

• 1. ___ nucleus or fibers: complete ___ 3rd nerve palsy
• 2. Dentatothalamic fibers in superior cerebellar peduncle or synapsing in___ __ = contralateral ataxia
• 3. Involvement of medial lemniscus causes ___ ___/___ loss

Answer 49

Paramedian midbrain (Benedikt)

•1. Oculomotor nucleus or fibers: complete ipsilateral 3rd nerve palsy

• 2. Dentatothalamic fibers in superior cerebellar peduncle or synapsing in red nucleus = contralateral ataxia
• 3. Involvement of medial lemniscus causes contralateral touch/vibration loss

Question 50

In ___ syndrome, the eyes cannot look up, and you have trouble with pupillary response to light (but they converge)

Answer 50

Parinaud

Question 51

What is this?

Answer 51

Paramedian midbrain palsy

• 1. Oculomotor nucleus or fibers: complete ipsilateral 3rd nerve palsy
• 2. Dentatothalamic fibers in superior cerebellar peduncle or synapsing in red nucleus = contralateral ataxia
• 3. Involvement of medial lemniscus causes contralateral touch/vibration loss