High yield test 2 Flashcards
In shaken baby syndrome what vein is torn that causes hemorrhaging?
bridging vein which creates a subdural space in between the arachnoid and the dural mater and can enter subarachnoid space
If there is a blockage of the internal jugular vein at the base of the school how does blood of the skull drain?
Blood would then drain through superficial veins of the school such as the opthalmic vein to the facial vein to common facial then back into internal jug, or through the vertebral venous plexus
what cranial nerves are associated with the cavernous sinus?
CN’s III, IV, V1, V2, sit on the edge of the sinus but CN VI sits inside the sinus directly behind the internal carotid artery
A patient presents with an infection or thrombis of the internal carotid artery inside the cavernous sinus. Which CN will be the first to be effected and the most effected? what muscle will be affected?
CN VI sits directly posterior to the internal carotid artery inside the sinus
LR which causes abduction of eyeball
where is the skull the thinnest and is most prone to injury?
Pterion which blunt injury can cause an epidural hemotoma.
what is the supratentorial fossa innervated by and primary blood supply?
V1 V2 V3 middle meningeal artery form maxillary artery
what innervates the underside of the tentorium in the posterior cranial fossa? (Dura of the posterior cranial fossa)
X, and C1 C2 via XII
where will large diameter neurons ascend the spinal column?
Within the posterior funiculus in the fasiculus cuneatus or fasiculus gracilis aka dorsal column
where will small diametre neurons ascend the spinal column?
within the spinothalamic tract
what type of neuron is the first neuron in any ascending pathway?
psuedounipolar
merkles discs respond to?
pressure pcml pathaway
ruffuni corpuscles respond to?
skin stretch pcml pathway
meissner’s corpuslce respond to?
fine touch pcml pathway
pacinian corpuscle respond to?
vibration pcml pathway
free nerve endings respond to what?
pain temperature and itch participate in spinothalamic pathway
what receptors respond to muscle stretch vs muscle tension?
golgi tendon organs respond to tension, muscle spindle respond to length
what kinds of somatic sensation does the PCML pathway include?
- discriminative touch (two point discrimination)
- vibration
- 3D form
- proprioception, conscious limb and joint position
What kinds of somatic sensation does the spinothalamic tract include (ALS)?
- non-discriminative touch (crude touch)
- thermal sensation
- nociception
- itch
- unconscious proprioception
where are the primary cell bodies, 1st synapse, location it enters spinal cord, decussates, 2nd synapse, and final destination for PCML pathway?
primary cell bodies are in the dorsal root ganglion then 1st synapse is in nucleus gracilis or nucleus cuneatus in the caudal medula, then enters spinal cord medial aspect of dorsal root in FC and FG, decussates internal arcuate fibers ventral to cuneatus and gracilis (becomes medial lemniscus), 2nd synapse on VPL of thalamus, final destination in primary somatosensory cortex via internal capsule and corona radiata
what receives information from lower body?
nucleus gracilis
what receives information from upper body?
nucleus cuneatus
Loss of the posterior spinal artery would result in disruption of the PCML pathway at what point?
loss of 2nd order cell bodies in the nucleus gracilis and nucleus cuneatus
Loss of the anterior spinal artery would disrupt the PCML pathway at what point?
lead to loss of internal arcuate fibers that form the medial lemniscus
what level of information does the gracile fasiculus carry?
medial below t6
what level of info does the cuneatus fasciculs carry?
lateral above t6
walk through the entire ALS (spinothalamic pathway)
transmits pain, temp, poorly localized touch, point o forigin is free nerve endings (TRP channels) with primary cell bodies in DRG 1st synapse in lamina 1 and 2, enters spinal cord in dorsal horn (lissaauers fassiculus to ascend at least 1 segment) then ascend through ALS tract, decussates in spinal cord after 1st synapse, 2nd synaps on vpl of thalamus then on to primary somatosensory cortex
where do 2nd order neurons of the spinothalimc pathway decussate?
at the vertebral level they enter (or one above) decussate in VENTRAL WHITE COMMISURE
loss of the middle portion of the somatosensory cortex could be from what artery and would result in loss of sensation to what areas of the body?
genitals foot lower limb loss of anterior cerebral artery
loss of the lateral portion of the somatosensory cortex could be from what artery and would result in loss of sensation to what areas of the body?
face tongue middle cerebral artery
The anterior spinocerebellar tract carries what kind of information?
Unconscious proprioceptive info from ipsilateral trunk and lower limb
-carry broad integrated information on entire limb
what kind of information does the rostral cerebellar tract carry?
unconscious proprioception from ipsilateral upper limb
-carry broad integrated information on entire limb
what kind of information does the posterior spinocerebellar tract carry?
Unconscious proprioceptive from ipsilateral trunk and lower limb
- fine detailed proprioceptive
- single muscle cells, muscle tendon complex
are cerebellar ataxia symptoms ipsilateral or contralateral?
always ipsilateral
describe the posterior spinocerebellar patheway and cuneocerebellar pathway?
point origin is muscle spindle fibers and golgi tendon organs, then primary cell bodies in DRG, 1st synapse in clarkes nucleus lamina VII (nucleus dorslalis) of thoracic cord if dorsal spinal cerebellar or accessory cuneate nucleus if caudal medulla if cuneocerebellar, enters spinal cord posterior funiculi hikes up dorsal columns (cuneocerebellar tract only does not decussate, 2nd synapse is in the vermis/paravermis of the cerebellum via inferior cerebellar peduncle final destination is deep cerebellar nuclei (via purkinji cells)
What kind of information does the cuneocerebellar tract carry?
unconscious proprioception from ipsilateral upper limb
- fine detailed proprioceptive
- single muscle cells, muscle tendon complex
what level determines if information travels with the cuneocerebellar tract vs the posterior cerebellar tract?
C8 below dorsal cerebellar above cuneate nucleus
describe the pathway of the anterior spinal cerebellar tract?
origin: muscle spindals, golgi tendon organs in muscles and joints primary cell bodies in DRG 1st synapse in Laminae VII enters spinal cord posterior funiculi decussates immediately in spinal cord second synaps in vermis/paravermis of cerebellum via superior cerebellar peduncle will then decussate again final destination deep cerebellar nuclei via perkinji cells
how can an infection spread from the scalp into the brain?
the emissary veins drain through the skull and enters the brain through dural sinuses, emissary veins function to cool the brain
a hematoma seen above the aponeurosis of the scalp is called what?
caput succedneum
a hematoma seen just below the aponeurosis of the scalp is called what?
subgaleal hematoma not limited by sutures gets worse after birth
a hematoma seen just below the pericardium of the skull is called what?
cephalohematoma limited to one bone due to tight adherence of sutures
what two muscles raise the upper eyelid and one muscle that depresses lower eyelid and innervations?
levator palpebrae superioris (voluntary striated)
and superior tarsal muscle (involuntary SMC sympathetic)
inferior tarsal muscle depresses lower eyelid
what muscle elevates the eybrow?
occipital frontalis
what is sjorgren syndrome?
autoimmune disease effecting primarily salivary and lacrimal glands
what foramen does the facial nerve exit?
stylomastoid foramen
describe the venous drainage of the skull?
superficially the supraorbital and supratrochlear veins form the angular vein with forms the facial vein which drains into common facial to i jug
where does lymph drainage from the lips/ chin drain?
submental nodes
where is the first neuron for visceral sensory information for CN VII?
geniculate ganglion
where is the second neuron for visceral sensory information in CN VII
solitary nucleus
where are the GVE-P’s for CN VII?
first neuron is superior salivary nucleus 2nd nueron is pterygopalatine ganglia or otic
where are the somatic sensory neurons for CN IX located?
1st neuron: Superior ganglion of IX
2nd neuron: Spinal trigeminal nucleus
where are the visceral sensory neurons for CN IX located
1st neuron: Inferior ganglion of IX
2nd neuron: Solitary nucleus
where are the GVE-P for CN IX located?
1st neuron: Inferior salivary nucleus
2nd neuron: Otic ganglion
where are the LMN’s for somatic motor of CN IX located?
nucleus ambiguus
where are the somatosensory neurons for X?
Somatic sensory
1st neuron: Superior ganglion of X
2nd neuron: Spinal trigeminal nucleus
where are the visceral neurons for X?
Visceral sensory:
1st neuron: Inferior ganglion of X
2nd neuron: Solitary nucleus
where are the somatic motor neurons for X?
nucleus ambiguus
where are the GVE-P for X?
Parasympathetic
1st neuron: Dorsal motor nucleus of X (VISCERAL MOTOR)
2nd neuron: Various ganglia
where do the psuedounipolar cell bodies sit for proprioceptive info of the face?
they are in the mesencephalic nucleus
the ventral trigeminothalamic tract contain what information
Spinal nucleus
crude touch
Pain, temperature
Contralateral
the dorsal trigeminothalamic tract contains what information?
Principal (Main, Chief) nucleus
Fine touch
Bilateral
talk me through the ventral trigeminothalamic tract
type info: pain temp, origin free nerve endings (TRP channels) primary cell bodies in trigeminal/semilunar/gasserian ganglion 1st synapse in spinotrigeminal nucleus in medulla, enters brainstem in Pons, descends to spinal trigeminal nucleus in medulla, decussates: Internal arcuate fibers in medulla, second synapse is: Ventral posterior medial nucleus (VPM) of the Thalamus, Final destination: Primary somatosensory cortex (via internal capsule and corona radiata)
explain the dorsal trigeminothalamic tract
info: tactile discrimination
origin: meissners corpuscle, pacinian corpuslce, ruffunis ending, merkels disc,
primary cell bodies in: trigeminal/semilunar/gassrian nucleus
1st synaps is in main sensory nucleus
enters brainstem: pons ascends contralaterally and ipsilateraly is mainly oral cavity
decussates: in pons ascends with medial lemniscus
second synapse: VPM of thalamus
final destination: somatosensory cortex
what causes wallenberg syndrome (lateral medullary syndorme) and how does is present?
stroke to PICA artery leads to ipsilateral pain and temp loss to face and contralateral pain and temp loss in body
horners syndrome
explain the paleospinothalamic tract pathway?
info: poorly localized pain, origin: free nerve endings, primary cell bodies in DRG, 1st synapse in lamina I-VI enters dorsal horn (lissaueres fassciuculus ascends 1 segent then travels bilaterally and ascends through anterolateral spinal thalamic tract, decussates in spinal cord after 1st synapse, 2nd synapse is intralaminar nuclei of the thalamus, final destination is bilateral cortex poorly localalized (includes cingulate gyrus and insula)
pathway for spinoreticular and spinomesencephalic tracts
info: Pain
origin: free nerve endings, primary cell bodies DRG,
1st synaps lamina 1-2, enters dorsal horn lissauers fassiculus ascend 1 segement, travel b/l through ALST
decussates in spinal cord after 1st synaspe
2nd synapse in medullary/pontine reticular formation/parabrachial nucleus (spinoreticular); periaquedcucatal grey matter ( spinomesencephalic) descend in DLF, 3rd synapse ipsilateral dorsal horn of spinal cord
what compounds can inhibit painful stimuli coming into the spinal cord?
seretonin, norepi
what kind of pain fibers carry visceral pain?
C-fibers
what bones in the skull come from NC cells?
all bones in front of ear/ frontal/ mandible, maxilla, zygomatic, hyoid
what bones in the skull come form paraxial mesoderm?
all bones behind ear, parital occipital
what time frame does the anterior frontanelle close?
around 18 months
what time frame does the anterolateral and posteriolateral frontanelle, and posterior frontanelle close?
around 6 months
what is craniosynostosis?
premature fusion of sutures
what can result from premature fusion of saggital sutures
can cause scaphocephaly protrusions on sides of head
what causes brachiocephaly?
premature fusion of coronal suture
achondroplasia primariyly effects what kind of bone growth?
long bone formation through premature closure of growth plates, has little effect on intermembranous bone formation like flat bones of skull however can narrow cervicl canal and foramen magnum
what makes up the fused medial nasal prominences?
nose ridge, tip, philtrum, and primary palate
what forms the uvula
created by fusion at caudal end of palatine shelves.
what is the cause of an oblique cleft?
- failure of maxillary prominence to fuse with lateral nasal prominence.
what is the cause of a primary cleft lip/pallet?
failure of maxillary prominence to fuse with medial nasal prominence (or intermaxillary segment).