Name The Lesion Flashcards
Clinical correlates and functional areas
Symptom:
Dizziness (vertigo), nausea
Vertebrobasilar Ischemia:
Vestibular nuclei, cerebellum or inner ear
Symptom:
Diplopia, dyscongugate gaze
Vertebrobasilar Ischemia:
Supranuclear or infranuclear eye movement pathways
Symtom:
Blurred vision or other visual disturbances
Vertebrobasilar Ischemia:
Eye movement pathways or visual cortex
Symptom:
Incoordination (ataxia)
Vertebrobasilar Ischemia:
Cerebellum or cerebellar pathways
Symptom:
Unsteady gait
Vertebrobasilar Ischemia:
Cerebellar pathways; long sensory or motor tracts
Symtom:
Dysarthria, Dysphagia
Vertebrobasilar Ischemia:
Corticobulbar pathways or brainstem cranial nerve nuclei
Symptom:
Numbness and tingling, particularly bilateral or perioral
Vertebrobasilar Ischemia:
Long somatosensory pathways or trigeminal system
Symptom:
Hemiparesis, quadriparesis
Vertebrobasilar Ischemia:
Corticospinal tract
Symptom:
Somnolence
Vertebrobasilar Ischemia:
Pontomesencephalic reticular formation or bilateral thalami
Symptom:
Headache at occipital region
Vertebrobasilar Ischemia:
Posterior fossa meninges and vessels (CN X and cervical roots)
Symptom:
Headache at frontal region
Vertebrobasilar Ischemia:
Supratentorial meninges and vessels (CN V; PCA is often CN V1)
Symptom:
Nonlocalized/diffuse headache
Vertebrobasilar Ischemia:
Supra- and/or infratentorial meninges and vessels
Midbrain Vascular Supply (Level 3) @ Superior Colliculus
SCA and proximal PCA
Midbrain Vascular Supply (Level 3) @ ML, STT, Red Nucleus, Substantia Nigra, Oculomotor Nucleus + EW Nucleus
Paramedian branches at top basilar artery (interpeduncular fossa)
Midbrain Vascular Supply (Level 3) @ Cerebral Pedunces, CST, CBT
Proximal PCA
Focal Vascular Syndrome to Midbrain basis
Name: Webers Syndrome
Vascular Supply: Branches of PCA + Top of Basilar Artery
Structures:
- Oculomotor nerve fascicles
- Cerebral Peduncles
Anatomical Clinical Feature(s):
- Ipsilateral third-nerve palsy
- Contralateral hemiparesis
Focal Vascular Syndrome to Midbrain tegmentum
Name: Claudes Syndrome
Vascular Supply: Branches of PCA + Top of Basilar Artery
Structures:
- Oculomotor nerve fascicles
- Red nucleus, superior cerebellar peduncle fibers
Anatomical Clinical Feature(s):
- Ipsilateral third-nerve palsy
- Contralateral ataxia
Focal Vascular Syndrome to Midbrain basis and tegmentum
Name: Benedikt’s syndrome
Vascular Supply: Branches of PCA + Top of Basilar Artery
Structures:
- Oculomotor nerve fascicles
- Cerebral peduncle
- Red nucleus, substantia nigra, superior cerebellar peduncle fibers
Anatomical Clinical Feature(s):
- Ipsilateral third-nerve palsy
- Contralateral hemiparesis
- Contralateral ataxia, tremor and involuntary movements
Rostral Pons Vascular Supply (Level 5) @ Superior Cerebellar peduncle
Superior Cerebellar Artery (SCA)
Rostral Pons Vascular Supply (Level 5) @ Reticular formation, Trigeminal nerve, Middle cerebellar penduncle, STT, ML
Basilar artery (circumferential branches = lateral pontine arteries)
Rostral Pons Vascular Supply (Level 5) @ Pyramidal tract or CST and CBT, ML, reticular formation
Basilar artery (paramedian branches)
Caudal Pons Vascular Supply (Level 6/7) @ Vestibular nuclei, facial nucleus and nerve vascicles, spinal trigeminal nucleus and tract, middle cerebellar peduncle, STT, descending sympathetic fibers
AICA and basilar artery (circumferential branches = lateral pontine arteries)
Caudal Pons Vascular Supply (Level 6/7) @ abducens nucleus, MLF, ML, pontine nuclei, pyramidal tract or CST and CBT
Basilar artery (paramedian branches)
Focal Vascular Syndrome to Medial pontine basis (rostral and caudal levels)
Name:
- Dysarthria Hemiparesis (pure motor hemiparesis)
- Ataxic Hemiparesis
Vascular Supply:
-Paramedian branches of basilar artery, ventral territory
Structures:
- Corticospinal and corticobulbar tracts
- Pontine nuclei and pontocerebellar fibers
Anatomical Clinical Features:
- Contralateral face, arm, leg weakness; dysarthria
- Contralateral ataxia (occassionally, ipsilateral ataxia)
Focal Vascular Syndrome to Lateral Caudal Pons
Name:
-AICA Syndrome
Vascular Supply:
-AICA
Structures:
- Middle Cerebellar Peduncle
- Vestibular nuclei
- Spinal trigeminal nucleus and tract
- STT
- Descending sympathetic fibers
Anatomical Clinical Features:
- Ipsilateral ataxia
- Vertigo, nystagmus
- Ipsilateral facial decreased pain and temperature sense
- Contralateral body decreased pain and temperature sense
- Ipsilateral Horner’s syndrome
Focal Vascular Syndrome to Dorsolateral rostral pons
Name:
-SCA syndrome
Vascular Supply:
-SCA
Structures:
- Superior Cerebellar Peduncle and Cerebellum
- Other lateral tegmental structure (variable)
Anatomical Clinical Features:
- Ipsilateral ataxia
- Variable features of lateral tegmental involvement (like AICA syndrome)
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to corticospinal and corticobulbar tracts
Name: Foville’s syndrome
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features: Contralateral face, arm, and leg weakness; dysarthria
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to facial colliculus
Name: Foville’s syndrome
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features:
- Ipsilateral face weakness (CN 7 nucleus and fasciles right there)
- Ipsilateral horizontal gaze palsy (CN 6 abducens nucleus right there)
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to abducens nucleus or paramedian pontine reticular formation (PPRF)
Name: Pontine wrong-way eyes
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features:
- Ipsilateral horizontal gaze palsy (CN 6 abducens nucleus right there)
- Typically comes along with contralateral face, arm, and leg weakness and eyes look TOWARD side of weakness
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to fascicles of facial nerve
Name: Millard-Gubler Syndrome
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features:
- Ipsilateral face weakness
- Typically comes along with contralateral face, arm, and leg weakness secondary to CST/CBT deficit
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to Medial Lemniscus
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features:
-Contralateral decreased position and vibration sense
Focal Vascular Syndrome to Medial pontine basis and tegmentum @ Level 6/7 or Caudal Pons
Damage to Medial Longitudinal Fasciculus (MLF)
Vascular Supply: Paramedian branches of basilar artery, ventral and dorsal territories
Anatomical Clinical Features:
-Internuclear ophtalmoplegia (INO)
Internuclear ophtalmoplegia (INO)
Disorder of conjugate lateral or horizontal gaze secondary to lesion of MLF. Affected individuals have slowed or limited idduction in the eye IPSILATERAL to the lesion, with associated abducting nystagmus in the contralateral eye.
Medullary Vascular Supply (Level 10/12) @ ML, Pyramidal tract, fascicles of hypoglassal nerve and hypoglassal nucleus
Vertebral artery (paramedian branches) and anterior spinal artery
Medullary Vascular Supply (Level 10/12) @ inferior olivary nucleus
Vertebral artery
Medullary Vascular Supply (Level 10/12) @ Inferior cerebellar peduncle, solitary nucleus and tract, NA, fascicles of vagus nerve, Spinal trigememinal nucleus and tract, STT, dorsal efferent nucleus of vagus, descending sympathetic fibers
Vertebral artery and PICA
Focal Vascular Syndrome to Medial Medulla
Name: Dejerine Syndrome (medial medullary syndrome_
Vascular Supply: Paramedian branches of vertebral artery and anterior spinal arteries
Structures:
- Pyramidal tract
- Medial lemniscus
- Hypoglossal nucleus and exiting CN XII fascicles
Anatomical Clinical Features:
- Contralateral arm or leg weakness
- Contralateral decreased position and vibration sense
- Ipsilateral tongue weakness
Focal Vascular Syndrome to Lateral Medulla
Name: Wallenberg’s syndrome (lateral medullary syndrome)
Vascular Supply: vertebral artery and anterior spinal arteries (more commonly than PICA)
Structures:
- Inferior Cerebellar peduncle, vestibular nuclei
- Spinal trigeminal nucleus and tract
- Spinothalamic tract
- Descending sympathetic fibers
- Nucleus ambiguus
- Nucleus solitarus
Anatomical Clinical Features:
- Ipsilateral ataxia, vertigo, nystagmus, nausea
- Ipsilateral facial decreased pain and temperature sense
- Contralateral body decreased pain and temperature sense
- Ipsilateral Horners syndrome
- Horseness, dysphagia
- Ipsilateral decreased taste
Horners Syndrome
Horner’s syndrome is a rare condition characterized by miosis (constriction of the pupil), ptosis (drooping of the upper eyelid), and anhidrosis (absence of sweating of one side of the face). It is caused by damage to the sympathetic nerves of the face.
Vascular Supply to Cerebellum: Top portion of vermis, superior zones on both dorsal and ventral sides
SCA territory
Vascular Supply to Cerebellum: SCP, MCP, ICP, flocculus with surrounding medial zones, very small portion of lateral hemispheres at farthest aspect on dorsal side
AICA territory
Vascular Supply to Cerebellum: Bottom portion of vermis, inferior zones on both dorsal and ventral sides including the nodulus
PICA territory
Vascular Supply to Forebrain: Along interhemispheric fissure, medial frontal lobe anterior to the preccentral gyrus, most of corpus callosum anteriorly, anterior cingulate gyrus
Anterior Cerebral Artery
ACA Key Functional Areas
- septal area
- anterior cingulate gyrus (limbic system -related cortex)
- primary motor cortex for the leg and foot areas, and the medial frontal micturition center
- additional motor planning areas in the medial frontal lobe, anterior to the precentral gryus
- primary somatosensory cortex for the leg and foot
- most of the corpus callosum except its posterior part.
Vascular Supply to Forebrain: Temporal-frontal areas surrounding lateral sylvian fissure, regions of BG and anternal capsule
Middle Cerebral Artery
Superior Cortical MCA Key Functional Areas
-Primary motor cortex for face and arm, and axons originating in the leg as well as face and arm areas that are traveling in the deep white matter toward the internal capsule as part of the corticobular or corticospinal tracts
-Broca’s area and other related gray and white matter important for language
expression – in the language-dominant (usually L) hemisphere
-Frontal eye fields (important for ‘looking at’ eye movements to the opposite side)
-Primary somatosensory cortex for face and arm (But be aware that this cortex and
even the primary motor cortex can be supplied by inferior branches in some people)
-Parts of lateral frontal and parietal lobes important for lateralized attention
(perceptions of one’s own body and of the outside world), visuospatial analysis, and
for expressing emotions with the voice and body language in the R hemisphere
Inferior Cortical MCA Key Functional Areas
-Wernicke’s and other related areas important for language comprehension in the
language- dominant (usually L) hemisphere
-Parts of the lateral parietal and temporal lobe important for lateralized attention, and
visuospatial analysis, and for the ability to interpret emotions in the voices and body
language of others – in the R hemisphere
-primary somatosensory cortex, and sometimes also part of the primary motor cortex
-Optic radiations. Axons that carry information about the contralateral superior
quadrants of the visual fields loop forward into the temporal lobe (they are located anterior and lateral to the temporal horn of the lateral ventricle). Recall that the optic radiations traveling deep in the parietal lobe carry information from the contralateral inferior quadrants.
Vascular Supply to Forebrain: Medial temporal lobe, diencephalon, midbrain, occipital lobe medial and inferior surfaces, medial parietal lobe, splenium of corpus callosum, inferior and medial temporal lobe with hippocampal formation
Posterior Cerebral Artery
Penetrating Branches of PCA Key Functional Areas
-DIENCEPHALON including thalamus, subthalamic nucleus, and hypothalamus
-MIDBRAIN including cerebral peduncle, third nerve and nucleus, superior cerebellar
peduncle, reticular formation
-Note: The upper parts of the Basilar artery also help supply the midbrain
Cortical Branches of PCA Key Functional Areas
PARIETAL AND OCCIPITAL LOBE (Posterior branches)
-Optic radiations and striate cortex (the primary visual cortex may be entirely
supplied by PCA, or the tip of the occipital lobe where the fovea is mapped may be
located in the border zone shared by PCA and MCA)
-Splenium of the corpus callosum (these crossing fibers participate in the transfer of
visual information to the language-dominant hemisphere)
MEDIAL TEMPORAL LOBE (Anterior branches)
-Posterior hippocampal formation and the fornix (these structures are critical for laying down new declarative memories)
Surface view of Brain Vascular Territories: Midbrain and portions of ventral temporal and occipital lobe
Posterior Cerebral Artery (PCA)
Surface view of Brain Vascular Territories: Midline of Pons
Basilar artery (paramedian branches)
Surface view of Brain Vascular Territories: Lateral Pons
Basilar artery (circumferential branches = lateral pontine branches)
Surface view of Brain Vascular Territories: Exposed portion of superior cerebellum
Superior Cerebellar Artery (SCA)
Surface view of Brain Vascular Territories: Exposed flocculus and medial portions of cerebellum
Anterior inferior cerebellar artery (AICA)
Surface view of Brain Vascular Territories: Exposed portions of inferior cerebellum (biventer lobule), tonsils, olives on medulla
Posterior inferior cerebellar artery (PICA)
Surface view of Brain Vascular Territories: lateral portions of pyramids and medulla (excluding olives)
Vertebral artery (lateral branches)
Surface view of Brain Vascular Territories: medial portions of pyramids and medulla
Vertebral artery (paramedian branches) and anterior spinal artery
Coronal view of Cerebral Arterial Territories: Thalamus
PCA deep branches
Coronal view of Cerebral Arterial Territories: Hippocampal formation, 1/2 of GPi, portion of internal capsule
Anterior choroidal artery
Coronal view of Cerebral Arterial Territories: temporal lobe
PCA
Coronal view of Cerebral Arterial Territories: GPe, 1/2 of GPi, Putamen, portion of internal capsule
MCA deep branches
Coronal view of Cerebral Arterial Territories: Insular gyrus, superior temporal lobe
MCA inferior division
Coronal view of Cerebral Arterial Territories: parietal lolbe superior to insular gyrus
MCA superior division
Coronal view of Cerebral Arterial Territories: Cingulum and Cingulate gyrus, body of corpus callosum
ACA
Horizontal/Axial view of Cerebral Arterial Territories : Cingulum and Cingulate Gyrus, Genu of Corpus Callosum
ACA
Horizontal/Axial view of Cerebral Arterial Territories : Caudate Head, anterior limb of internal capsule
ACA deep branches
Horizontal/Axial view of Cerebral Arterial Territories : Putamen, Globus Pallidus, Insula
MCA deep branches
Horizontal/Axial view of Cerebral Arterial Territories : Posterior limb of internal capsule
Anterior choroidal artery
Horizontal/Axial view of Cerebral Arterial Territories : Thalamus
PCA deep branches
Horizontal/Axial view of Cerebral Arterial Territories : Splenium of corpus callosium, midline occipital regions
PCA
Horizontal/Axial view of Cerebral Arterial Territories : lateral parietotemporaloccipital regions
MCA inferior division
Horizontal/Axial view of Cerebral Arterial Territories : lateral fontoparietal regions
MCA superior division
Blood vessels supplying the BG and thalamus: Head of caudate, Anterior putamen
Penetrating branches of ACA (e.g., recurrent artery of Heubner)
Blood vessels supplying the BG and thalamus: Caudate nucleus body of putamen
Lenticulostriate arteries derived from MCA which is derived from internal carotid artery
Blood vessels supplying the BG and thalamus: Posterior putamen, Globus pallidus, tail of caudate
Anterior choroidal artery derived from ACA which is derived from internal carotid artery
Blood vessels supplying the BG and thalamus: Thalamus
Posterior choroidal artery, Thalamogeniculate arteries and Thalamoperforator arterys derived from PCA which is derived from basilar artery
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L MCA superior division
Deficits:
- Right face and arm weakness of the UMN type
- Nonfluent or brocas aphasia
- In some cases there may also be some R face and arm cortical-type sensory loss
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L MCA inferior division
Deficits
- Fluent or Wernickes aphasia
- R visual field deficit
- There may also be some right face and arm cortical-type sensory loss.
- Motor findings are usually absent and patients may initially seem confused or crazy but otherwise intact, unless carefully examined.
- Some mild right-sided weakness may be present, especially at the onset of symptoms
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L MCA deep territory
Deficits:
- Right pure motor hemiparesis of the UMN type.
- Larger infarcts may produce “cortical” deficits, such as aphasia as well.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L MCA stem
Deficits:
- Combination of MCA syndromes with R hemiplegia, R hemianesthesia, R homonymous hemianopia and global aphasia.
- There is often left gaze preference especially at the onset, caused by damage to L hemisphere cortical areas important for driving eyes to the right.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R MCA superior division
Deficits:
- Left face and arm weakness of the UMN type.
- Left hemineglect is present to a variable extent.
- In some cases, there may also be some left face and arm cortical-type sensory loss.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R MCA inferior division
- Profound left hemineglect.
- Left visual field and somatosensory deficts are often present; however these may be difficult to test convincingly because of the neglect.
- Motor neglect with decreased voluntary or spontaneous initiation of movements on the L side can also occur.
- However, even patients with L motor neglect usually have normal strength on the L side, as evidenced by occassional spontaneous movements or purposeful withdrawal from pain. Some mild, left-sided weakness may be present.
- There is often a right gaze preference, especially at onset.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R MCA deep territory
Deficits:
- L pure motor hemiparesis of UMN type.
- Larger infarcts may produce “cortical” deficits such as L hemineglect as well.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R MCA stem
Deficits:
- Combination of R MCA syndromes with left hemiplegia, left hemianesthesia, left homonomymous hemianopia and profound left hemineglect.
- There is usually a right gaze preference, especially at onset, caused by damage to R hemisphere cortical areas important for driving the eyes to the left.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L ACA
Deficits:
- R leg weakness of UMN type and R leg cortical-type sensory loss.
- Grasp reflex
- Frontal lobe behavioral abnormalities
- Transcortical aphasia can also be seen.
- Larger infarcts may cause R hemiplegia.
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R ACA
Deficits:
- L leg weakness of UMN type and L leg cortical-type sensory loss.
- Grasp reflex
- Frontal lobe behavioral abnormalities
- L hemineglect can also be seen.
- Larger infarcts may cause L hemiplegia
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of L PCA
Deficits:
- Right homonymous hemianopia.
- Extension to spenium of the corpus callosum can cause alexia without agraphia.
- Larger infarcts, including the thalamus and interanl capsule, may cause aphasia, right hemisensory loss, and right hemiparesis
Major Clinical Syndromes MCA/ACA/PCA Territories:
Infarct of R PCA
Deficits:
- Left homonymous hemianopia
- Larger infarcts including the thalamus and internal capsule may cause left hemisensory loss and left hemiparesis.
Common Lacunar Syndromes:
Pure motor hemiparesis or dysarthria hemiparesis
Clinical Features
Unilateral face, arm, and leg UMN type weakness, with dysarthria
Common Lacunar Syndromes:
Pure motor hemiparesis or dysarthria hemiparesis
Possible Locations for Infarct
- Posterior limb of internal capsule (common)
- Ventral pons (common)
- Corona radiata
- Cerebral peduncle
Common Lacunar Syndromes:
Pure motor hemiparesis or dysarthria hemiparesis
Possible Vessels Involved
- Lenticulostriate arteries (common), anterior choiridal artery or perforating brances of PCA for Posterior limb of IC infarct
- Ventral penetrating branches of basilar artery for Ventral pons infarct
- Small MCA branches for corona radiata infarct
- Small proximal PCA branches for cerebral peduncle infarct
Common Lacunar Syndromes:
Ataxic Hemiparesis
Clinical Features
Same as pure motor hemiparesis (i.e., unilateral face, arm and leg weakness of UMN type) but with ataxia on same side as weakness.
Common Lacunar Syndromes:
Ataxic Hemiparesis
Possible locations for infarct
- Posterior limb of internal capsule (common)
- Ventral pons (common)
- Corona radiata
- Cerebral peduncle
Common Lacunar Syndromes:
Ataxic Hemiparesis
Possible vessels involved
- Lenticulostriate arteries (common), anterior choiridal artery or perforating brances of PCA for Posterior limb of IC infarct
- Ventral penetrating branches of basilar artery for Ventral pons infarct
- Small MCA branches for corona radiata infarct
- Small proximal PCA branches for cerebral peduncle infarct
Common Lacunar Syndromes:
Pure sensory stroke (thalamic lacune)
Clinical Features
Sensory loss to all primary modalities in the contralateral face and body.
Common Lacunar Syndromes:
Pure sensory stroke (thalamic lacune)
Possible locations for infarct
Ventral posterior lateral nucleus of thalamus (VPL)
Common Lacunar Syndromes:
Pure sensory stroke (thalamic lacune)
Possible vessels involved
Thalmoperforator branches of the PCA
Common Lacunar Syndromes:
Sensorimotor stroke (thalamocapsular lacune)
Clinical Features
Combination of thalamic lacune (i.e., sensory loss to all primary modalities in the contralateral face and body) and pure motor hemiparesis (i.e, unilateral face, arm, and leg UMN type weakness)
Common Lacunar Syndromes:
Sensorimotor stroke (thalamocapsular lacune)
Possible locations for infarct
- Posterior limb of internal capsule
- Either thalamic VPL or thalamic somatosensory radiation
Common Lacunar Syndromes:
Sensorimotor stroke (thalamocapsular lacune)
Possible vessels involved
Thalmoperforater branches of the PCA or lenticulostriate arteries
Common Lacunar Syndromes:
Basal ganglia lacune
Clinical Features
Usually asymptomatic, but may cause hemiballismus (i.e., flinging/ballistic/chorea like movement of proximal arm or leg)
Common Lacunar Syndromes:
Basal ganglia lacune
Possible locations for infarct
- Caudate
- Putamen
- Globus pallidus
- STN
Common Lacunar Syndromes:
Basal ganglia lacune
Possible vessels involved
- Lenticulostriate
- Anterior choroidal or Heubners arteries
Watershed Areas
ACA-MCA Watershed
Coronal View:
-Goes from corona radiata (lateral to cingulum) to top gyrus border of ACA/MCA regions through the minimal first pronounced frontal sulcus visible.
Horizontal View:
-Goes from edge of anterior limb of internal capsule to top gyrus border of ACA/MCA regions through the minimal first pronounced frontal sulcus visible.
Watershed Areas
MCA-PCA Watershed
Coronal View:
-Goes from edge of putamen to bottom gyrus border of MCA/PCA regions and covering the second pronounced gyrus inferiorly
Horizontal View:
-Goes from edge of atrium of lateral ventrical to bottom gyrus border of MCA/PCA regions and covering the second pronounced gyrus inferiorly
Watershed Areas
Define + Causes
- Watershed areas refers to arterial end-zones.
- They are areas between major arterial supples (ACA/MCA, MCA/PCA) or at the end of small arteries (lenticulostriates)
- Watershed damage occurs after drop in blood pressure secondary to stroke, heart attack or massive bleeding in the body
Anterior Spinal Cord Syndrome
- Most often caused by embolism due to complications of surgery (angiography) or trauma
- Damage to STT causes lose of pain and temperature sensation BELOW the level of the lesion.
- Damage to anterior horn cells produces LMN weakness AT the level of the lesion.
- Larger lesions can includ CST and cause UMN symptoms below the lesion.
- Posterior cord rarely affected by vascular pathology due to 2 posterior arteries and their connections to eachother
NTL Lab Intro:
Left Hemisphere Lesions
Language deficit
Graphesthesia (inability to ID something drawn to your hand)
Eyes deviate left
R motor deficits
NTL Lab Intro:
Right Hemisphere Lesions
L hemispatial neglect
Loss of prosody
Eyes deviate right
Left motor deficits
NTL Lab Intro:
Internal capsule
Face, arm and leg involvement on the same side could indicate lesion of the internal capsule
NTL Lab Intro:
Brainstem lesions
Sensory and motor signs in the body can be crossed with CN deficits
Medial pontine syndrome, results from occulsion of paramedian brances of basilar artery
NTL Lab Intro:
Cerebellar Signs
Ataxia, nystagmus or dysdiadochokinesia are associated with cerebellar or cerebellar peduncle lesions.
Cerebellar signs are found on the SAME side of the body as the lesion.
NTL Lab Intro:
Bitemporal Hemianopsia
Optic chaism affected
NTL Lab Intro:
Homonymous Hemianopsia
Will localize it to either optic tract, LGN, or occipital lobe
NTL Lab Intro:
Convergence
If CN3 is damaged they WILL NOT BE able to converge and look at the nose.
If CN3 is intact and they CAN CONVERGE, likely damage between CN3 and 6 via MLF.
NTL Lab Intro:
Horizontal gaze deficits
Tells you where the lesion is, they will LOOK without deficits to the side of the lesion.
Appropriate Right Gaze = R MLF deficit.
“He can look to the right, so R MLF deficit”
or
IPSILATERAL MLF to the eye that cannot adduct past midline.
“Issues with adduction of R eye when looking left, so R MLF deficit”
NTL Lab Intro:
Spinal Cord Lesions - Motor
Flaccid paralysis immediately after lesion, followed by spastic paralysis. Symptoms are on the SAME SIDE as lesion.
NTL Lab Intro:
Spinal Cord Lesions - Sensory
Loss of pain and temperature on OPPOSITE side of body.
(because fibers cross immediately in ventral white commissure)
Loss of fine touch and proprioception on SAME SIDE of body.
(because fibers dont cross until you get up to sensory deccussation)
Classic presentation:
Brown Sequard Syndrome: IPSILATERAL weakness, IPSI LOSS of proprioception/vibration and CONTRA loss of pain temperature secondary to HEMICORD lesion
NTL Lab Intro:
Spinal Cord Lesions - General
Typically no facial involvement. Think about the dermatomes.
NTL Lab Intro:
Cranial Nerve Lesions
Loss of the entire nerve, including motor and sensory distribution (and associated reflexes!)
Think about unique functions of each nerve
May include loss of parasympathetic functions CN 3, 7, 9, 10
Example: Lack of pupillary response to light or lack of saliva production
NTL Lab Intro:
Peripheral Nerve Lesion
Loss of the entire nerve, including motor and sensory distribution (and associated reflexes!)
LMN symptoms
Can see similar symptoms with central lesions, but central lesions are accompanied by other symptoms as well
NTL Lab Intro:
Hx for differential diagnosis
Sudden onset suggests a vascular problem like hemorrhage or stroke
Progressive onset suggests a tumor or other progressive disease (e.g., MS)
NTL Lab Intro:
Nystagmus
Cerebellum OR vestibular nuclei
NTL Lab Intro:
Nausea/vomiting
Medulla OR vestibular nuclei OR increased ICP
NTL Lab Intro:
Difficulty speaking
Cortical aphasia OR facial weakness OR tongue weakness
NTL Lab Intro:
Anterior Spinal Artery Infarct
Will affect anterior 2/3 of the spinal cord (symptoms will include weakness)
NTL Lab Intro:
Posterior Spinal Artery Infarct
If you have an infarct of the posterior spinal artery, it will involve the dorsal columns (symptoms tend to not include weakness but will have sensory loss of vibration and proprioception)
NTL Lab Intro:
Vascular distribution in brainstem
In general, most brainstem syndromes are seperetaed into ventromedial and dorsal-lateral brainstem
NTL Lab Intro:
Vascular distribution in brainstem (ANTEROMEDIAL)
Anteromedial areas suppled by anteromedial (paramedian) branches of basilar bifuncation and P1 segment
NTL Lab Intro:
Vascular distribution in brainstem (ANTEROLATERAL)
Anterolateral areas supplied by anterolateral (short circumferential) branches of the quadrigeminal and medial posterior choroidal arteries.
NTL Lab Intro:
Vascular distribution in brainstem (LATERAL)
Lateral areas (which are sort of square shaped and off midline; see images) are supplied by lateral branches of quadrigeminal (level of inferior colliculus) quadigeminal and posterior medial choroidal arteries (level of superior colliculus)
NTL Lab Intro:
Vascular distribution in brainstem (MOST DORSAL)
Dorsal regions like superior colliculus/opposite of cerebral peduncles are supplied by quadrigeminal and superior cerebellar arteries (level of inferior colliculus), quadrigeminal and posterior medial choroidal arteries (level of superior colliculus)
NTL Lab Intro:
Vascular distribution in brainstem (FAR LATERAL @ LEVEL 3 on)
Thalamogeniculate artery
NTL Lab Intro:
Complete R facial droop
CN 7
NTL Lab Intro:
Vomiting/Dizziness
CN 8, vestibular nucleus, ICP
NTL Lab Intro:
Diminished taste sensation
CN 7, 9, X, NTS
NTL Lab Intro:
Diminished pain and temperature one side of body
Contralateral STT/ALS (as its already crossed)
Contralateral spinal cord lesion
NTL Lab Intro:
Decreased pain and temperature to one side of face
IPSILATERAL spinal nucleus of V, Chief sensory or VTTT
NTL Lab Intro:
Weber syndrome:
Mesencephalon
Vascular distribution is P1 branch
Weber syndrome:
-Corticospinal fibers in cerebral peduncle result in contralateral hemiparesis with ipsilateral CN 3 palsy
NTL Lab Intro:
Claude Syndrome
Mesencephalon
Vascular distribution is P1 branch
Claude syndrome:
-Red nucleus and cerebellothalamic fiber insult resulting in contralateral ataxia and tremor with ipsilateral CN 3 palsy
NTL Lab Intro:
Benedikt syndrome
Combination of both Weber and Claude
NTL Lab Intro:
Medial pontine syndrome
Pons
Vascular distribution paramedian brances of basilar
Medial Pontine Syndrome:
- Corticospinal fiber damage resulting in contralateral hemiparesis
- ML damage resulting in contralateral loss of proprioception/vibration (left side)
- Abducens nucleus or nerve fiber damage resulting in ipsilateral loss of eye abduction (lateral rectus)
- PPRF damage results in paralysis of conjugate gaze toward the side of the lesion.
NTL Lab Intro:
Lateral pontine syndrome
Pons
Vascular distribution long circumferential branches of basilar
Lateral pontine syndrome (Millard-Gubler syndrome)
- Middle/superior cerebellar peduncle damage causing ataxia and falling towards side of lesion.
- Vestibular and cochlear nerves/nuclei damage resulting in ipsilateral deafness, vertigo, tinnitus and vomiting.
- Facial motor nucleus damage resulting in ipsilateral facila paralysis
- Trigeminal motor nucleus damage resulting in ipsilateral paralysis of masticatory muscles
- Sympathetic fiber damage resulting in ipsilateral horner’s syndrome
- STT and nucleus resulting in ipsilateral loss of facial pain/temp and contralateral loss of body pain/temp
- PPRF damage causing paralysis of conjugate horizontal gaze
NTL Lab Intro:
Medial medullary syndrome (Dejerine syndrome)
Medulla
Vascular distribution branches from anterior spinal artery
Medial medullary syndrome (Dejerine syndrome)
- Corticospinal fibers in pyramid damage resulting in contralateral hemiparesis
- ML damage resulting in contralateral loss of touch/position/vibration sense
- Hypoglossal nerve nucleus resulting in deviation of tongue to IPSILATERAL side
NTL Lab Intro:
Lateral medullary syndrome (Wallenberg Syndrome)
Medulla
Vascular distribution branches from anterior spinal artery
Lateral medullary syndrome (Wallenberg Syndrome)
- STT and nucleus resulting in ipsilateral loss of facial pain/temp and contralateral loss of body pain/temp
- NA damage causing dysphagia and decreased gag
- Sympathetic fiber damage resulting in ipsilateral horner’s syndrome
- Damage to vestibular nuclei causing nystagmus, diplopia and tendency to fall to ipsilateral side
- ICP damage causing ipsilateral ataxia
NTL Lab Intro:
Cortical Stroke Syndromes
MCA
MCA
Contralateral face/arm weakness, sensory loss, eye movement abnromalities and/or aphasia (L side)
NTL Lab Intro:
Cortical Stroke Syndromes
ACA
ACA
Contralateral leg weakness, behavioral abnormalities.
Behavioral changes due to involvement of the limbic system, caudate and some orbitofrontal cortrex.
NTL Lab Intro:
Cortical Stroke Syndromes
PCA
PCA
Contralateral homonymous hemianopia with macular sparing, memory problems.
Memory deficits due to involvement of inferior temporal lobe, parahippocampal gyrus and hippocampus
Eye Movement Lab Intro:
Foveation
The system evolved to maintain foveation.
Fovea is the area of the retina with the highest visual acuity.
Eye Movement Lab Intro:
3 primary types of movements
Saccades
Smooth pursuit
Vergence (con- or di-
Can be supranuclear or nuclear; under reflexive or voluntary control; seperate systems for vertical + horizontal eye movements
Eye Movement Lab Intro:
Saccades
Quick, darting CONJUGATE movements which direct the eyes to a new target.
Conjugate meaning same time, direction, perfectly nysnc.
FEF control voluntary saccades
Superior colliculi control reflexive saccades in tandem with TST.
Eye Movement Lab Intro:
Smooth Pursuit
A slower conjugate movement which allows for tracking of a moving object or of a stationary object while we are moving
Eye Movement Lab Intro:
Vergence
Convergence is DISconjugate movement of both eyes toward midline to allow for focusing on a near object by adjusting the angle between the eyes
Horizontal Gaze under Supranuclear Control
FEF for saccades is CONTRA to direction of gaze.
Look horizontally to RIGHT.
LEFT FEF has to fire to activate RIGHT PONS/PPRF/6/MLF/3
TOPJ for smooth pursuit is is IPSILATERAL to direction of gaze.
Look horizontally to RIGHT.
RIGHT TOPJ fires to activate RIGHT PONS/PPRF/6/MLF/3.
Vestibulo-ocular reflex (VOR)
Reflexive movements which are under nuclear control alone (specifically, under control of the vestibular nuclei in the brainstem. These constitue what is called the VOR.
Supranuclear = Gaze Palsy
FEF lesion
PPRF lesion
Nuclear = Gaze palsy
Nuclear lesion (only 6 nucleus is relevant here
Intranuclear = Mixture of gaze and nerve palsy
MLF Lesion (L5) MLF Lesion + nucleur lesion (L6)
Infranuclear
Nerve Palsy
CN 3, 4, 6 palsy
6th nucleus lesion
Gaze palsy to ipsilateral side that CANNOT be overcome by VOR
PPRF lesion
Gaze palsy to the ipsilateral side that CAN be overcome by VOR, acutely eyes may be deviated contralaterally
FEF lesion
palsy of saccades to contralateral side. Acutely, eyes may be deviated toward the side of the lesion
INO
Internucleur opthalmoplegia:
Lesion of the MLF. Eye ipsilateral to the lesion cannot adduct. Contralateral eye can normally abduct, but nystagmus present.
1 1/2 syndrome
Combination of ipsilateral gaze palsy and INO
PPRF lesions at the level of abducens…
PPRF lesions at the level of abducens are associated with ipsilateral gaze palsy and loss of reflex vestibular (and tonic neck) movements This presumes that there is a critical synapse within the caudal PPRF for the vestibulo-ocular pathways or that the functional integrity of the PPRF at that level is necessary for vestibulo-ocular eye movements