Lecture 4: Meninges and Ventricles Continued Flashcards
What sits underneath the Corpus Callosum?
The Lateral Ventricle
What seals the left and right side of the Lateral Ventricle?
The Septum Pellucidum
What does the Septum Pellucidum do?
It seals off the left and right side of the lateral ventricle
What sits on the floor of the Lateral Ventricle?
The choroid plexus
What is the Choroid Plexus?
The blood vessel in the Lateral Ventricle that allows the transport of ions, molecules, amino acids, nutrients and water to produce CSF
What structures does the Third Ventricle sit around?
The diencephalon which is made of the thalamus and hypothalamus
How does fluid travel through the midbrain?
Through the cerebral aqueduct
What sits in the posterior of the cerebral aqueduct?
The superior and inferior colliculi
How is CSF made in the fourth ventricle?
By more choroid plexus
Where does the Choroid plexus make CSF?
•Lateral Ventricles
•Third Ventricle
What are the walls of the fourth ventricle made of?
Posteriorly two of the walls are made of the cerebellum and in the front the brainstem
How does CSF get to the subarachnoid space?
The Median and Lateral apertures
What is the Cisterna Magna?
A space of CSF that is bigger than usual that CSF goes before it reaches the subarachnoid space
What are the functions of CSF?
•Supports mass (floats brain)
•Cushions CNS (spatial buffering)
•Contains proper electrolytes for CNS
•Route for chemical messengers
How does CSF leave the subarachnoid space?
Through arachnoid granulations
What are the two types of Hydrocephalus?
Communicating and noncommunication
What is Communicating Hydrocephalus?
Hydrocephalus outside the ventricular system. Obstruction occurs at cisterns or arachnoid villi
What is Noncommunicating Hydrocephalus?
Hydrocephaly within the ventricular system so there is a blockage within the ventricles
When does Communicating Hydrocephalus occur?
When fluid reabsorption system fails and ventricles begin to enlarge
When does Non communicating Hydrocephalus occur?
When ventricles become blocked or trapped by obstructions such as a tumour, cyst, or scarring from infection
What are the two blood supplies of the brain?
•Internal Carotid
•Vertebral-Basilar
What can the Internal Carotid be divided into?
•Middle Cerebral Artery (MCA)
•Anterior Cerebral Artery (ACA)
What can the Vertebral-Basilar artery be divided into?
The Posterior Cerebral Artery (PCA)
What can the Vertebral-Basilar artery be divided into?
The Posterior Cerebral Artery (PCA)
What does the External Carotid Artery supply?
The face, neck and middle meningeal artery
What does the Middle Meningeal Artery arise from?
The External Carotid Artery
What does the Middle Meningeal Artery arise from?
The External Carotid Artery
What does the Internal Carotid Artery Supply?
The anterior part of the brain
What supplies the anterior part of the brain?
The Internal Carotid Artery
What supplies the posterior part of the brain?
The Vertebro-Basilar System
What does the Internal Carotid Artery supply?
The anterior part of the brain: Frontal, Parietal and temporal lobes
What does the Verterbo-basilar system supply?
The Posterior part of the brain: Occipital lobe, Cerebellum, Brainstem and upper cord
What are the two main suppliers of the Brain?
The Internal Carotid Arterial System and the Vertebro-Basilar System
What is the Circle of Willis comprised of?
•MCS
•Posterior communicating artery
•PCA
•ACA
•Anterior Communicating artery
What does the Circle of Willis allow for?
Blood can flow between the Internal carotid arterial system and Vertebro-basilar system
