nervous system anatomy 1- keagan

Question 1

3 meningeal layers (between brain and skull)
What tissue types?
Where is trabeculae?

Answer 1

1. dura mater- outer most layer, connective tissue- tough layer
   clings to internal surface of skull but 2 layers seperate from venous sinuses
2. arachnoid- stratified epithelium- spider web like mesh
   normally flush agaisnt dura but has trabeculae extending to pia mater
3. pia mater- simple epithelium (single layer of cells)
   thin transparent layer flush w brain surface

Question 2

subarachnoid space
Where?
What is in it?

Answer 2

between pia and arachnoid space
trabeculae, blood vessels, filled w CSF

Question 3

conus medularis

Answer 3

thin/pointy end of spinal cord in L2 area

Question 4

cauda equina

Answer 4

nerve roots of lowest levels of spinal cord

Question 5

filum terminale
What does it form (inferiorly)

Answer 5

descending ligament that the spinal cord is anchored to in subarachnoid space

continues downward to form coccygeal ligament

Question 6

dorsal root ganglion

Answer 6

bundle of cell bodies of sensory neurons

Question 7

gray matter v white matter

Answer 7

gray- neuron cell bodies and dendrites
white- myelinated axons and glial cells

Question 8

motor neuron
Where does its axon exit

Answer 8

neuron cell body and dendrites in gray matter- axon exits via ventral root

Question 9

roots v rami

Answer 9

roots- nerves coursing from spinal cord, exiting the vertebral column through intervertebral foramen

rami- divisions of the distal end of the spinal nerve

Question 10

denticulate ligaments

Answer 10

stabilize the spinal cord in horizontal plane (similar to arachnoid trabecula)

Question 11

venous drainage network of spinal cord

Answer 11

continuity- posterior venous plexus, posterior internal plexus, spinal veins

potential access for infection, metastasis

Question 12

lumbar cistern

Answer 12

L3 and down where only caudal equine is present and needle can be stuck in to get cerebral spinal fluid sample

Question 13

cerebral spinal fluid circulation- to where

Answer 13

to subarachnoid space
1. CSF filteres from plasma from choroid plexus (specialized blood vessels) inside the ventricular system
2. Aperatures- in 4th ventricle allows CSF to flow from inside 4th ventricle to subarachnoid space- surrounding brain and spinal cord
3. CSF removed from subarachnoid space into venous blood

Question 14

traumatic tap

Answer 14

red coloring of cerebral spinal fluid sample due to blood

if later samples continue to be red the hemmorrhage

Question 15

Low glucose levels in cerebral spinal fluid could be due to what?

Answer 15

bacterial or fungal infection- normal w viral infection

Question 16

Increased protein in cerebral spinal fluid due to what?

Answer 16

due to auto-antibodies, inflammation or, infection

Question 17

Increased Lymphocyte concentration in cerebral spinal fluid due to what?

Answer 17

infection or inflammation

Question 18

What does cloudy or filament CSF indicate?

Answer 18

Cloudy - bacterial infection
Filament - fungal infection

Question 19

Ventricular System & locations

Answer 19

1 & 2 are left and right of lateral ventricle in each hemisphere
1 & 2 connect with 3 by intraventricular foramen
3 connect 4 with cerebral aqueduct
4 narrows to central canal of spinal cord

Question 20

sympathetic levels

Answer 20

1st neuron @ T1-L2/3
1st neuron synapse SYNS ganglion of 2nd neuron
2nd neuron projects to target

Question 21

Parasympathetic levels

Answer 21

1st neuron @ brain stem or S2-4
1st neuron synapses at ganglion
2nd neuron projects to target