spinal cord

Question 1

meningeal coverings (from spinal cord out)

Answer 1

spinal cord -> pia mater -> subarachnoid space -> arachnoid mater (spider-like projections) -> epidural space -> dura mater (durable and hard)

Question 2

what is present in subarachnoid space

Answer 2

CSF (continuous with subarachnoid space of cranium)

Question 3

what is the epidural space and what is present in it

Answer 3

true space between dura and vertebral periosteum, containing fat and venous plexus

Question 4

where is epidural/spinal anaesthetic injected

Answer 4

L3-L4 or L4-L5

Question 5

why is epidural/spinal anaesthetic injected at levels L3-L4 or L4-L5

Answer 5

epidural space not filled with spinal cord so nerves move out of the way to inject epidural nerve block; can be put into subarachnoid space to get CSF or to inject spinal blocks (e.g. for C-section)

Question 6

dura and brain vs dura and spine

Answer 6

no true gap between dura and brain, but is true gap between dura and spine, so anaesthetics can be injected into epidural space or CSF can be taken from subarachnoid space in spine (lumbar regions), but not in brain

Question 7

CSF flow

Answer 7

flows from lateral ventricles via interventricular foramina into third ventricle, then fourth ventricle via cerebral aqueduct in brainstem, them into subarachnoid space and central canal of spine