Ventricles, CSF, Sinuses Flashcards
what ventricular space is associated with the telencephalon?
lateral ventricles
what ventricular space is associated with the diencephalon?
third ventricle
what ventricular space is associated with the mesencephalon?
cerebral aqueduct
what ventricular space is associated with the metencephalon?
fourth ventricle
what ventricular space is associated with the myelencephalon?
fourth ventricle
describe the anterior (frontal) horn of the lateral ventricle
located in the frontal lobe, anterior to the foramen of Monro
- anterior wall and roof: corpus callosum
- medial wall: septum pellucidum
- floor and lateral wall: head of caudate nucleus
describe the body (corpus) of the lateral ventricle
located in the frontal and parietal lobes (posterior to foramen of Monro) and extends posteriorly to the splenum of the corpus callosum
- roof: corpus callosum
- medial wall: septum pellucidum
- floor: fornix, choroid plexus, dorsal thalamus, stria terminalis and inf. body of caudate nucleus
describe the posterior (occipital) horn of the lateral ventricle
located in the occipital lobe
- roof: corpus callosum
- medial wall: an eminence, tied to the calcarine fissure
describe the inferior (temporal) horn of the lateral ventricle
located in temporal lobe
- roof: tail of caudate nucleus
- floor: hippocampus
- anterior wall: amygdala
describe the third ventricle
thin vertical cavity, occupying the midline between the diencephalic hemispheres
- roof: choroid plexus and body of fornix
- floor: basal hpoythalamic structures
- lateral wall: thalami, hypothalami, subthalami
- anterior wall: lamina terminalis
- post. wall: epithalamus
describe the fourth ventricle
rhomboid cavity overlying the pons and rostral medulla and is connected to the third ventricle by the mesencephalic cerebral aqueduct, which is frequently involved in obstructive hydrocephalus
- roof: medullary vela and choroid plexus
- lateral boundaries of floor: sup. and inf. cerebellar peduncles
describe the contents of CSF
- produced by choroid plexus, ependymal cells, astrocytes, pia and arachnoid vessels
- ions are actively transported with passive movement of water
- CSF is clear and low in glucose, protein, K, Ca
- Na, Cl and Mg higher than in serum
name causes of hydrocephalus
- obstructive (non-communicating)
- pathogens and immune cells
- congenital stenosis
- tumors
- communicating
- normal pressure hydrocephalus
- “wet, wacky, wobbly” triad
- subarachnoid hemorrhage
- hydrocephalus ex vacuo
- Huntington’s disease
- normal pressure hydrocephalus
describe the normal flow of CSF through the ventricular system
- flow from the lateral ventricles into the third ventricle via the interventricular foramina (of Monro)
- from the third ventricle into the cerebral aqueduct
- from the cerebral aqueduct into the fourth ventricle
- very small amounts of CSF trickle between the fourth ventricle and the central canal
where does CSF go after it exits the fourth ventricle?
- CSF exits the fourth ventricle into the subarachnoid space via the foramina of Luschka (lateral) and Magendie (medial)
- extraventricular CSF follows the subarachnoid space
- it returns to the venous system through small membranous villi, the arachnoid granulations, located along the superior sagittal sinus
- the arachnoid villi react to pressure gradients between the subarachnoid space and venous system to form one-way valves, ensuring the unidirectional movement of fluid into the venous system