PowerPoint Presentation

A Brief Introduction to NeuroanatomyPart Four: The Great VesselsCerebrovasculature Lucas Brammar

Learning Objectives: The Great Vessels

Outline of the main arterial supply to the brain and brainstem

Venous sinuses

Ventricular System and Cerebrospinal fluidOutline

Blood and the Brain

Blood supply essential (O2) anoxia Highly vascular15% of Cardiac output

Image: Wellcome Collection

Arterial Supply of the BrainBlood supply from two arteries:Internal Carotid ArteriesVertebral Arteries

These branch at the base of the brain producing the cerebral arteries

The cerebral arteries are united in an arterial anastamosis the Circle of Willis

Brachiocephalic TrunkC6Subclavian arteryVertebral ArteryInternal Carotid ArteryCarotid CanalCarotid SiphonJugular ForamenImage: Wikimedia CommonsCommon Carotid Artery

Image adapted from:J Valakaikiene et al, Transcranial Color-Coded Duplex Sonography for Detection of Distal Internal Carotid Artery Stenosis,American Journal of Neurology, 2007

Internal Carotid ArteryMiddle Cerebral ArteryAnterior Cerebral ArteryPosterior Communicating ArteryPosterior Cerebral ArteryBasilar ArteryVertebral ArteryAnterior Spinal

Anterior CirculationPosterior CirculationImage: Lucas BrammarAnterior Communicating

7

Image: Anatomist90, Wikimedia Commons

Image: Cecceco master, Wikimedia Commons

Trajectories of the Cerebral Arteries

Medial SurfaceLateral SurfaceAnterior Cerebral ArteryMedial surface of the brain, superio-medial surface Middle Cerebral ArteryLateral surface of the brain, most of the temporal lobePosterior Cerebral ArteryOccipital lobes, part of temporal lobesImage: Wikimedia Commons

3D Perspective

Middle CerebralArteryPosterior CerebralArteryAnterior cerebralarteryVertebral Artery

Clinical ImportanceStroke (Cerebrovascular Disease)

Sudden onset of focal neurological signs lasting longer than 24hrs

Two broad classifications:IschaemicHaemorrhagic

Image: Wikimedia Commons, beliefnet.comIschaemic Stroke

Berry Anyeurisms on the Circle of WillisImage: Lucas Brammar, beliefnet.comHaemorrhagic StrokeHypothetical ArteryBrain tissue

Venous Drainage of the BrainMany veins scattered throughout the brain, drain into venous sinuses (spaces)

Spaces are formed where the periosteal dura and dura surrounding the brain separate

All meet and drain into the internal jugular vein

Image: Wikimedia Commons

Venous Sinuses of the Brain

Image: Wikimedia CommonsSuperior SagittalSinusInferior sagittal sinusStraight SinusOccipital SinusInternal Jugular Vein

Venous Sinuses of the Brain

Image: Wikimedia CommonsTransverse Sinus(Left)Sigmoidal SinusCavernous SinusSuperior Petrosal SinusInferior Petrosal Sinus

The Triangle of Death

Facial vein communicates with cavernous sinusFractures infection Brain

Image: Wikimedia Commonsc

Contents of the Cavernous SinusInternal Carotid ArteryCNV1 and V2CNIII (Occulomotor)CNIV (Trochlear)CNVI (Abducent)Image: Wikimedia Commons

The Ventricular System

Neural tube neural canalExtensive folding produces ventricles (spaces) within the brainFrom choroid plexusCirculates cerebrospinal fluid

Image: Wikimedia Commons

Ventricular System

Image: http://antranik.org/wp-content/uploads/2011/11/ventricles-of-the-brain-horn-interventricular-foramen.jpg

http://3.bp.blogspot.com/_7JAArcms7_8/SKskm-HKgAI/AAAAAAAAAhc/o5MLUbFC-3I/s400/BrainMRI_Sagittal.jpgLateral VentricleThird VentricleCerebral AqueductFourthVentricle

Clinical ImportanceHydrocephalusBlockage of CSF flowDilatation of ventricles

Thank you!

Thank you!A Brief Introduction to NeuroanatomyWritten & Presented byLucas Brammar