Chapter 1 Meninges and CSF Flashcards
Major blood supply of the dura
Middle meningeal artery
Level where the spinal epidural space is largest
Second lumbar vertebra (also contains internal venous plexus)
Epipial tissue bands that anchor the spinal cord to the dural tube
Denticulate ligaments
Blood vessels of the spinal cord lie within the _______, whereas cerebral vessels lie on ________.
Epipial layer; the surface of the intima pia
Where is the epipial layer absent?
Over the convex surface of the cerebral cortex
Arteries found in the superior cistern / cisterna ambiens
Great vein of Galen, posterior cerebral and superior cerebellar arteries
CSF flow into the venous sinuses begins when CSF pressure exceeds venous pressure by:
3-6cm of water
Tissue origin of brain parenchyma, neuroglia, ependyma, and leptomeninges
Ectoderm
CSF has higher concentrations of (3 ions) and lower of (2 ions) compared to plasma
CSF has higher Na, Cl, Mg and lower K, Ca (and glucose) than plasma
Total volume of CSF
140ml (25ml in ventricles)
Net production of CSF
400-500ml/day (0.35ml/min)
CSF pressure in recumbent position
100 to 150 mm H2O
CSF pressure in sitting position
200 to 300 mm H2O
What forms the blood-brain barrier?
Capillary endothelium with tight junctions between contiguous cells
Regions of the brain devoid of a blood-brain barrier
- Pineal body
- Subfornical organ
- Organum vasculosum of the lamina terminalis (or supraoptic crest)
- Median eminence of the hypothalamus
- Neurohypophysis
- Area postrema
