Cerebrovasculature

Dr. Croce at work as a Graduate

Neuroscience Student (wow is he

hot!)

2

What is this disorder and how can it be explained via the ventricular system of the brain?

Internal Carotid System

Vertebral System

Two Systems�Internal

Carotid and Vertebral

Internal Carotid System

1.  ICA

2.  MCA

3.  ACA

4.  P Comm A

5.  A Comm A

MCAIC

ACA

A. Com. A

Undersurface of brain showing major branches of the internal

carotid system

P. Com. A

Lateral View of Cerebral Cortex�Showing Branches of MCA Feeding Frontal, Parietal, and

Temporal (Superior-Lateral Parts) Lobes

Medial (Midsagittal) View of Cerebral Cortex Showing Branches of ACA and PCA

Anterior Cerebral A. supplies blood to most of the medial wall of the Cortex (PCA supplies

occipital and temporal lobes)

ACA

Orbital A.Frontopolar A.

Pericallosal A.

Callosomarginal A.

Corpus Callosum

Lateral Ventricle

Internal Capsule &Basal Ganglia

Lateral Striate Arteries Arteries to LateralHemisphere

(not Occipital L.)

Middle cerebral Artery(MCA)

Connects Two ACAs

Anterior CommunicatingArtery

HypothalamusInternal Capsule

Basal Ganglia

Medial Striate Artery

Frontopolar A. Callosomarginal A. Pericallosal A.

Major Branches include

Ascend into Long. Fiss.and Supplies MedialWall of Hemisphere

Anterior Cerebral Artery(ACA)

Internal Carotid Artery(ICA)

Summary of The Internal Carotid System

Vertebral-Basilar System

1.  Vertebral A.

2.  PICA

3.  Basilar A.

4.  AICA

5.  Pontine A.

6.  SCA

7.  PCA

8.  Spinal Arteries

MCA

IC

ACA & A. Com. A

Undersurface of brain showing major branches of internal

carotid and basilar arteries

P. Com. A

P. Cerebral. A

Sup Cer. A

Basilar A

CN III

CN II

Supplies Median

and Paramedian

Medulla &

Vertebral Canal

Anterior Spinal A.

Int. Auditory Artery

Supplies Inner Ear

Ant. Inferior Cerebellar A.

Supplies Upper Medulla

Lower Pons, & Anterior-

Inferior Cerebellum

Pontine Arteries

Supplies Deep Portions

of Pons

Posterior Cerebral Artery

is Connected to Internal carotid

Artery via Posterior

Communicating Artery

Posterior Cerebral Artery

Supplies Lat. Occip. L.; medial

Surface of

Temporal & Occipital Lobes

Superior Cerebellar Artery

Supplies Superior

Portions of Cerebellum

Major Branches

of

Basilar

Artery

Basilar Artery

Supplies

Dorsolateral Medulla,

4th ventricle

Post. Infer. cerbellum

Post. Inferior

Cerebellar A.

Vertebral Arteries

Combine to Form

Basilar Artey

Summary of The Vertebral-Basilar System

Summary of Cerebral

Vasculature

Summary of Cerebral

Vasculature

Exterior View of Ventricles

Circulation of Cerebrospinal

Fluid (CSF) Exiting of CSF Through Arachnoid

Villi

Pathologies to Meningeal Spaces

•  Subdural Hematoma-- Blood accumulating in subdural space due to lacerations in superior veins.

•  Meningitis-- Infection of the CNS involving the meninges.

•  Meningioma-- Begnin, slow growing tumors.

CEREBRAL SPINAL FLUID

•  FORMATION

–  CSF IS FORMED BY THE CHOROID PLEXUS.–  NORMAL CSF PRODUCTION: 20 ml/h.

HYDROCEPHALUS•  DEFINITION:

–  DIVERSE GROUP OF CONDITIONS WHICH RESULT FROM IMPAIRED CIRCULATION AND RESORPTION OF CSF.

TYPES OF HYDROCEPHALUS•  OBSTRUCTIVE OR NON-

COMMUNICATING-- OBSTRUCTION WITHIN THE VENTRICULAR SYSTEM

•  NON OBSTRUCTIVE OR COMMUNICATING -- –  BLOCKAGE WITHIN SUBARACHNOID SPACE;

OR,–  MALFUNCTION OF ARACHNOID VILLI–  SYMPTOMS-- ONE SEES THE THREE “Ws”--

WACKY (DEMENTIA), WOBBLY (ATAXIA), AND WET (INCONTINENCE)

•  TREATMENT--

SOME CAUSES OF HYDROCEPHALUS

•  SPINA BIFIDA

•  LESIONS OR MALFORMATIONS OF THE POSTERIOR FOSSA

–  CHIARI MALFORMATION

–  DANDY- WALKER SYNDROME

–  TUMORS

•  MENINGITIS

CHIARI MALFORMATION

•  CAUSE: DISPLACEMENT OF CEREBELLAR TONSILS INTO THE CERVICAL CANAL. LEADS TO:

–  PROGRESSIVE HYDROCEPHALUS.

–  ELONGATION OF THE 4TH VENTRICLE.

–  DISPLACEMENT OF INFERIOR VERMIS, PONS, AND MEDULLA INTO CERVICAL CANAL

DANDY-WALKER SYNDROME•  CYSTIC EXPANSION OF

THE 4TH VENTRICLE IN THE POSTERIOR FOSSA.

•  CAUSE: DEVELOPMENTAL FAILURE OF ROOF OF 4TH VENTRICLE DURING EMBRYOGENESIS.

•  LEADS TO:

–  MALDEVELOPMENT OF CEREBELLUM

–  90 % HAVE HYDROCEPHALUS

–  ENLARGEMENT OF 4TH VENTRICLE

–  PROMINENT OCCIPUT

Can you Answer These?

•  What are the two major branches of the internal carotid artery?

•  What are the major branches of the basilar artery?

•  What is the group name of the arteries that feed the basal nuclei and internal capsule?

•  Can you name the ventricles of the brain?•  What is hydrocephalus? A chiari

malformation?