CN V and VII Flashcards
what are the 3 divisions of CN V
V1 - opthalmic (sensory)
V2 - maxillary (sensory)
V3 - mandibular (sensory and motor)
what muscles does CN V3 provide motor innervation for ?
muscles of mastication and tensor tympani and tensor palatini (MOM and twins)
what is the main general sensory crainal nerve of the head
CN V
at what level of the brainstem would you be able to find the trigeminal main sensory nucleus, and trigeminal motor nucleus ?
midpons
what are the 2 ascending projections of CN V
trigeminal spinal nucleus, main trigeminal sensory nucleus
what is the path of the ascending trigeminal spinal nucleus ?
contralateral projection to VPM of thalamus, synapses then to postcentral gyrus
the postcentral gyrus is found on what lobe ?
parietal lobe area 3,1,2
the main trigeminal sensory nucleus is responsible for sensing what ?
discriminative touch, vibration, and proprioception of jaw
what major tract or pathway is the trigeminal main sensory nucleus a homologue of ?
posterior collumn/medial lemniscus pathway
there are 2 individual ascending pathways that make up the trigeminal main sensory nucleus, what are there differences
- one CROSSES midline then joins medial lemniscus pathway to the VPL then to postcentral gyrus
- one stays UNCROSSED and ipsilaterally ascends to VPM
the trigeminal spinal nucleus is responsible for sensing what ?
pain, temperature, crude touch
what are the 3 divisions of the trigeminal spinal nucleus
pars oralis (oral nucleus) pars interpolaris (interpolar nucleus) pars caudalis (caudal nucleus)
what division of the trigeminal spinal nucleus is responsible for sensing pain and temperature and crude touch
pars caudalis
what is the pars interpolaris division of the trigeminal spinal nucleus responsible for sensing ?
trigemino-autonomic reflexes
what nucleus of CN V would be found in a cross section of the midbrian
trigeminal mesencephalic nucleus
the when second order neurons of the trigeminal spinal nucleus cross the midline, what significant path/tract do they join ?
Anterolateral pathway/spinothalamic tract
where does the anterolateral/spinothalamic tract terminate ?
VPM of thalamus, synapses and ascends to postcentral gyrus
explain the “onion peel” representation, and what nuclei/origin of the trigeminal nerve is it referring to ?
Referring to pars caudalis of trigeminal spinal nucleus
-type of somatotopic organization (inverted face representation) where V1 division ends most vetral in posterior horn and V3 ends most dorsal
what would cause the largest amount of sensory loss, an injury to the most dorsal aspect of the trigeminal spinal tract or most ventral ?
injury to the dorsal aspect would cause the most sensory loss
75 percent of sensory fibers in the tooth pulp sense what ? the remaining 25 % sense ?
pain, temperature
-touch and pressure
what is trigeminal neuroglia
brief episodes of excruciating pain in the dist. of one or more division of the trigeminal nerve
what division of the trigeminal nerve is usually associated with trigeminal neuralgia
V3