Neuro-B2- Brainstem, Blood supply, Cerebellum

Caudal pons supply by?

*AICA* + *Basilar* brs.

*Gray cortical matter* on cerebellum contain?

*Molecular* (stellate+basket) *Purkinje* (Purkinje) *Granule* (granule+Golgi)

Cerebellar *dysarthria* d/t lesion in?

*Neocerebellum* = *Pontocerebellum*= *cerebrocerebellum*= (YELLOW)

post. (Dorsal) spinal A= branch of ?

*PICA* or *Vertebral*

Neocerebellum = - aka? - Fx? (YELLOW)

*Pontocerebellum*= *cerebrocerebellum* Post. lobe; lat. hemispheres Receives axons from pontine nuclei(*corticopontocerebellar* tracts). Fx. Timing, motor planning, coordination of limb mvt.

Branches of the Vertebral Arteries

*Post. spinal*; *Ant. spinal* (ASA); *PICA*

2 division of *inf. cerebellar peduncle*

*Restiform* & *Juxtarestiform*

Rostral pons supply by?

*SCA* + *Basilar* brs. (Paramedian, Short and Long circumferential arteries)

Paleocerebellum = - aka? - Fx? (YELLOW)

*Spinocerebellum* (Receives SCT) Anterior lobe + vermis + paravermal regions. Fx.: *Posture/balance* - motor execution

Archicerebellum = - aka? - Fx?

*Vestibulocerebellum* Flocculo-nodular lobe Fx.: balance & eye mvt.

*Thalamogeniculate* (PCA br) supply?

*geniculate bodies* of thalamus, ventral lateral and ventral posterior nuclei.

- L - Lateral Medullary Synd/ PICA synd. / Wallenberg - Artery= PICA (branch of vertebral)

-

Branches of the *Internal Carotid Artery*

- *ACA* → (A1=RAH= Med. stri. ; A2= leg) - *MCA*→ (M1= lat. stri. ; M2=insula; M3=cortex) - *Ophthalmic*→ central retinal A; ... - *Post. comm.* - *Ant. Choroidal*→ post limb of IC; hippocampus; amygdala; 3rd ventricle; LGN(vision); tail of caudate, Crus cerebri; optic tract

2 synd. d/t occlusion of *ASA*?

- *Ant. cord synd.* - *Medial Medullary Synd.*

Medial Inferior Pontine Syndrome (Foville's syndrome)

- *CN 6* ( Ipsil) - *CBT* (Contl) - *CST* (Contl) - *pontine nuclei* (Bilateral ataxia) - *ML* (Contl) - *CN7* Maybe

Lateral Inferior Pontine Syndrome: (AICA Syndrome)

- *CN7* sensory+motor( Ipsil) - *CN8* cochlear+ vestibular (ipsil) - *CN5 sensory* (Ipsil) pain & temp of face. - *Cerebellar Peduncles* (Ipsi) limb & gait ataxia. - *STT* (Contl) pain & temp of body - *Horner's syndrome* (ipsil) b/c damage to Descending Sympathetic Tract (w/ STT & Spinal Lemniscus)

*Stellate*, *basket*, and *Golgi* interneurons are excitatory/inhibitory?

- *Inhibitory*

2 synd. d/t occlusion of *PICA*?

- *Post. Vermis Synd.* - *Lat. Medullary Synd.* (Wallenberg/ PICA synd.)

*Anterior vermis* synd.

- *Rostral vermis* synd. -Degeneration of ant. portion of vermis. - Results from malnutrition ass. w/ *alcoholism*. (e.g., Korsakoff's) - Sx.= ==>* lower limb & trunk ataxia*

Opthalmic artery supply

- *central retinal A* (a br.)=> *blindness* - Frontal area of scalp - Ethmoid & frontal sinuses - Dorsum of nose

XXXXXXXXXXXX what pass *internal capsule*?

- Cortico-ponto-cerebellar, - Cortico-reticular Cerebellar, -Cortico-olivary Cerebellar

*Restiform* body of inf. cerebellar peduncle

- Dorsal (post) SCT, - cuneocerebellar, - olivocerebellar tracts

XXXXXXXXXXX inf. cerebellar peduncle

- Dorsal (post.) SCT, - cuneocerebellar, - olivocerebellar tracts - vestibulocerebellar (archicerebellum ) - cerebellovestibular tracts -cerebroreticulocerebellar

Damage : Neocerebellum (Cerebrocerebellum/Lateral hemispheres)

- Hypotonia - Dysdiadochokinesia - Dysmetria (over/under shooting) - Dysarthria (slurred speech) - Intention tremor

Cerebellar Sx.?

- Hypotonia - Postural & gait - Ataxia - Dysdiadochokinesia - Reflex disturbances - Ocular disturbances - Disorders of speech - Dysmetria - Intention tremor - Nystagmus

Hemmorhage

- Sudden neuro Sx. ; *headache* - d/t HTN, aneurysms, arterovenous malform. - may cause *comma*

XXXXXXXXXXXX Sup. cerebellar peduncle

- Ventral (Ant.) SCT -neocerebellum efferents = Dentate nuc. - Interposed (Emboliform = globose nuc.)- rubrospinal neurons??= paleocerebellum (spinocerebellum) cortex???? -Dentothalamic Pathway

PICA supply?

- inf. *vermis*, - central nuclei of cerebellum, - inf. side of cerebellar hemispheres. Also - *Medulla*, & - *choroid plexus* of the *4th* ventricle.

Amyloid angiopathy hemorrhage

- now MCC of intracranial bleeding - amyloid deposition in medium &small cortical & *leptomeningeal* vessels → brittle vessel - occurs in *cerebral cortex* & *subcortical white matter*; MC in *frontal & parietal lobes*.

*Climbing* fibers

- terminal fibers of these olivocerebellar tracts -*Excitatory*

*Juxtarestiform* body of inf. cerebellar peduncle

- vestibulocerebellar - cerebellovestibular tracts

hypertensive hemorrhage

- ↑BP→ vessel rupture→ bleeding - Brain *parenchymal*, & *endothelial* damage→ cytotoxic & vasogenic edema→ displacement of brain structures

Vasogenic Edema

- ↑brain *endothelial* permeability → proteins leak out. - w/in hrs-days - irreversible -*white* matter

*Posterior vermis* synd.

-*Caudal vermis* synd. - Often d/t medulloblastomas. - Damage to *flocconodular* lobe→ vestibular prob.???!!! - Sx= difficulty in maintaining posture of the trunk and neck, and staggering gait. ==> *posture & balance* prob.

*Mossy* fibers

-Mostly from crossed and uncrossed *pontocerebellar* fibers -via *middle cerebellar peduncle* -*Excitatory*

Midbrain bl supply?

PCA

midbrain blood

PCA & SCA

Midbrain Syndromes: Parinaud's Synd. Benedikt's Synd. Weber's Synd.

Parinaud's Synd.= A Benedikt's Synd. = B Weber's Synd. = C

Transient Ischemic Attacks (TIA's)

Precede thrombotic stroke (40%)-Are not always predictive of thrombotic stroke. *Temporary* neurological deficits, usually clearing w/in *min- hrs*.

*Ant. SCT* → cerebellum via?

Sup. Peduncle (leg)

*Cerebellar Peduncles* connect cerebellum to?

Superior→ midbrain, pons Middle→ pons. Inferior→ medulla

Central brs. of PCA?

Thalamogeniculate Thalamoperforate Calcarine Quadrigeminal Medial posterior choroidal

*Thalamoperforate* (PCA br) supply?

Thalamus and parts of hypothalamus, parts of midbrain.

Medulla bl. supply?

Vertebral aa (PICA, ASA)

3 parts of cerebellum

Vestibulocerebellum Spinocerebellum Pontocerebellum

MC locations for *hypertensive hemorrhage* are?

deep gray matter, sp. *putamen*, *thalamus*, *cerebellum* and *pons*

Damage to vestibulocerebellum?

dizzyness, nystagmus, nausea, vomiting & vertigo.

Embolism

during *activity*, rarely by TIA source= heart diss (thrombosis) -consciousness intact

AICA supply

lat. caudal pons,( not rostral)

Hematoma

localize -bl. w/in tissue d/t leakage from BV → bluish discoloration (ecchymosis) + pain

*Medial posterior choroidal* (PCA br) supply?

midbrain

*Quadrigeminal* (PCA br) supply?

midbrain

caudal medulla supply by?

more by post. spinal A

Subclavian steal syndrome:

occlusive atherosclerosis of a *subclavian* A(proximal location) experience brainstem synd when *exercising*. Pt. may show BP differences b/w arms, as well as presyncope and syncope.

cerebellum cortex

outer cortex = gray matter, inner=white matter

Virchow-Robin space

small perivascular extensions of the subarachnoid space that surround the blood vessels as they penetrate the brain.

why mostly *thrombotic* strokes occur during *sleep*?

↓ BP→ clot block A

Arteriovenous malformation (AVM):

arteries connect directly to veins→ vein can't handle P → dilate (swell)→ masses → risk rupture. * Nidus*

Origin of *rubrospinal* tract

red nucleus

Damage to the midline (*vermis*/SCT/paleocerebellum)?

truncal ataxia. BILATERAL

subclavian A give rise to?

vertebral A.

Cerebellum Pathways ****

vestb. is *WRONG*, should pass Inf. peduncle**** Mossy fibers is WONG too?!

CBT damage/lesion ?

• Contralateral: - *lower face* paralysis (CN7) - *tongue* - *uvula*

Cytotoxic Edema

-hypoxic event- d/t failure of ATP-dependent ion *(Ca/Na) transport*. - w/in min-hrs -reversible - *gray* matter

level of *consciousness* in Embolism vs. Hemmorhage

-occlusive strokes (embolism) *consciousness* is often preserved. -Hemmorhage= may cause *comma*

Lateral Superior Pontine Syndrome (Caused by occlusion of the superior cerebellar artery) (NOT IMPT- DON"T STUDY THIS)

1. Damage to Middle and Inferior Cerebellar Peduncles Ipsilateral limb and trunk ataxia. 2. Damage to Part of Cerebellum Dystaxia, dysmetria, and intention tremor. 3. Damage to Spinothalamic and Spinotrigeminal Tracts Contralateral loss of pain and temperature sense from body, ipsilateral P & T from face. 4. Damage to Descending Sympathetic Tract Ipsilateral Horner's syndrome. 5. Damage to Medial Lemniscus Contralateral loss of proprioception, vibration and discriminative touch from lower extremities and trunk*.

Recurrent artery of Heubner supplies ?

=*medial* striate = ACA-A1 supply *head of C*, ant. *P* and *G*, ant. limb of *IC*.

Ventral Spinocerebellar Tract

=Ant. SCT sup. cerebellar peduncle -Terminate in vermis and paravermis regions of the anterior and posterior lobes as *mossy fibers* - for postural-lower limbs, coordinate- upright gait

Dorsal Spinocerebellar Tract

=Post. SCT Inf. Peduncle Clark Nuc.

Lenticulostriate (*lateral* striate)

MCA- M1 supply *C, G, P, IC*. (Dorsal head, & whole body, of *caudate nucleus*. Parts of lentiform nucleus (*globus pallidus* and *putamen*). *Internal capsule* (part of anterior limb along with ACA, the genu, and posterior limb along with anterior choroidal).)

Anterior Cerebral Artery (ACA) br.

A1, A2 (after Acom.)

lower 1/3 of spinal cord supply by?

Adamkiewicz

Deep Middle Cerebral vein

Along with anterior cerebral and striate veins, forms the basal vein. Drains insula.

rostral medulla supplied by?

Ant. spinal (*ASA*), *PICA*, & *vertebral* aa

dysarthria= slurred speech

Articulation = slurring. Prosody = all syllables are equally emphasized

Thrombosis

Atherosclerotic plaque damage vessel wall → fibrin + platelets → thrombus → Embolism

Pons bl. supply?

Basilar, AICA

Labyrinthine arteries

Br. of *Basilar* A (80-85% br. of *AICA*) Travels w/ CN7 & 8 innervate *internal ear*

Pontine arteries

Br. of Basilar A

Superior cerebellar artery (SCA)

Br. of Basilar A Superior surface of cerebellum, pons, & *pineal gland*.

Posterior cerebral artery (PCA)

Br. of Basilar A part of temporal lobe (*hippocampus*) & occipital lobe; thalamus, midbrain, *geniculate bodies*, choroid plexus (lat. & 3rd vent.)

Paresis (hemiparesis)

CST damage

*Charcot-Bouchard* (or *miliary aneurysms*)

Chronic *HTN* results in small lesions → vascular rupture

*Great Cerebral* Vein (or Great Vein of *Galen*)

Empties into the straight sinus. Great cerebral is formed from the union of the thalamostriate, and choroid veins.

Superficial Middle Cerebral

Drains lateral surface of cerebral hemispheres. Passes through lateral sulcus and empties into cavernous sinus.

Opthalmic artery br. of?

ICA

*Post. SCT* → cerebellum via?

Inf. Peduncle (trunk & arm)

ACA supply?

Medial- 'leg' area of pre- and post-central gyri

Reticular formation damage in Midbrain vs. Pone

Midbrain --> coma Pone brain --> No sleep

brain stem blood supply:

Midbrain = PCA Pons= Basilar, AICA Medulla= Vertebral aa (PICA, ASA)

does cerebellar lesions → paralysis, muscle atrophy, or sensory loss?

No no direct connection to LMN's.

XXXXXXXXXXXXX Middle cerebellar peduncle

No efferent *cortico-ponto-cerebellar* tract pass -cerebroreticulocerebellar

pineal gland supply by?

SCA

CST Sx.? (corticospinal tract )

a) Paresis (hemiparesis) b) Babinski (+) c) Hoffman's (+) d) Abdominal reflex (-) e) Cremasteric reflex (-) f) Spasticity, which is *hyper-reflexia* of DTR's, clonus, and increased muscle tone (rigidity).

where Acetylcholine, dopamine, norepinephrine, and serotonin receptors are located?

cerebellum

internal carotids A arise from?

common carotid A

cerebellum lobes

flocculonodular lobe can only be seen from below

Fastigial Pathways

go to - Vestibular Nuclei - RF

Cuneocerebellar Tract

hands (cuneo-) Inf. cerebellar Peduncle

Origin of *Olivocerebellar* tract

inf. olivary nucleus (medulla oblongata)

Angioplasty/Stenting

inserted into femoral artery

Unilateral damage to cerebellar hemisphere (pontocerebellum)?

ipsil. deficits of arms and legs.

Cerebellar functions

posture & balance (CN8), muscle tone

*Calcarine* (PCA br) supplies ?

primary visual area.

lower spinal cord supply by?

radicular and segmental aa

- coordination; - contains *CN 3 & 4*.

red nucleus

Area of Tegmentum (in midbrain) that also plays a role in "eye blink" response

red nucleus

where arteries are located?

subarachnoid space

Superior Cerebral vein empty into?

superior sagittal sinus