Trigeminal system Flashcards

1
Q

what are the three divisions of the trigeminal nerve and name if they are sensory or motor or both?

A

V1- ophthalmic - sensory
V2- maxilllary - sensory
V3- mandibular -sensory and motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T/F CN V is the Major Sensory nerve to the head and contains both proprioception and nociception

A

true
remember proprioception is DCML
nociception is ALS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

peripheral sensory afferents of the head converge at what?

A

trigeminal ganglion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

trigeminal ganglion is to the head as?

A

dorsal root ganglion is to the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the four nuclei of the trigeminal nucleus

A

mesencephalic nucleus
chief sensory nucleus (DCML)
spinal trigeminal nucleus (ALS)
motor nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the boundaries of the trigeminal nucleus?

A

midbrain to C3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

the second order neurons from the chief nucleus go both ipsilateral and contralateral to the VPM to maintain what?

A

symmetrical facial movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

all the contra lateral neurons travel to the thalamus in what?

A

trigeminothalamic tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what two nuclei are involved in the jaw jerk reflex?

A

the mesencephalic and motor nucleus

** this basically the function of these two nuclei and don’t really participate in much else.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where do second order trigeminal neurons originate?

A
  • principal (chief) trigeminal nuclei(DCML) pons

- spinal trigeminal nucleus (ALS) medulla/spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

chief trigeminal nucleus

A

mediates fine touch, joint, vibration

located in pons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

when do the second order neurons decussate?

A

immediately and head to the trigeminothalamic tract and head to the thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

spinal trigeminal nucleus

A

mediates pain and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how far does the spinal trigeminal nucleus descend into the spinal cord?

A

C2-C3 and is continuous with the dorsal horn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

why is the spinal trigeminal nucleus said to be messy?

A

because the decussation can happen anywhere in the whole nucleus
**similar to tract of lissauer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

when fibers from the spinal nucleus decussate what tract do they join?

A

spinothalamic tract

17
Q

secondary neurons from the trigeminal nerve synapse in what part of the thalamus?

18
Q

from the thalamus the fibers travel through what?

A

internal capsule in the posterior limb

19
Q

describe local gate control of nociceptive inputs

A
  • C fibers will inhibit the interneuron and activate the secondary neuron
  • alpha and beta fibers will activate the interneuron to inhibit the secondary neuron
  • *since the alpha and beta fibers are fast than the C fibers you can over ride the pain by rubbing an area of pain.
20
Q

T/F Transmission of nociceptive information can be inhibited by activation of cutaneous afferents?

21
Q

mesencephalic nucleus

A

sensory
mandibular proprioception
**primary neuron will be in here NOT trigeminal nucleus

22
Q

motor nucleus

A
  • muscles of mastication
  • homologous to ventral horn of spinal cord
  • corticobulbar upper motor neurons synapse on lower motor neurons originating in this nucleus
23
Q

jaw jerk reflex

A
  • muscle spindle from masseter senses it being pulled and sends signal to mesencephalic nucleus, which then synapses on the motor nucleus to masseter muscle to constrict.
  • 2 neurons
24
Q

what does the presence of an exaggerated jaw jerk reflex imply?

A

bilateral disease above the level of the pons

25
eye blink response
touch the cornea, V1 senses this and sends information to the chief nucleus, which the synapses on the facial nucleus to blink *3 neurons
26
is the eye blink consensual?
yes
27
in the eye blink response is the ipsilateral side slower or faster?
faster because there are less neuronal synapses than on the contra lateral side
28
what purpose does the reticular formation play in the eye blink response?
makes you move and get out of the way | rubrospinal tract
29
in you cut the neuron in the medulla of the eye blink response what happens?
you lose the consensual response
30
dental procedures that cause inferior alveolar nerve injury
``` implant root canal fracture of mandible local anesthetic extraction of third molar ```
31
the inferior alveolar nerve block includes what nerves?
``` lingual inferior alveolar mental incisive long buccal ```
32
teeth do not have motor or parasympathetic nerves. They do have sympathetic nerves, what is their job?
involved in anti inflammation | also required for eruption of teeth
33
if the needle enters the inferior alveolar nerve what can happen?
partial nerve injury with paresthesia/dystesthesia that generally resolves. However on rare occasions can develop into a sustained neuropathic pain