BMB 1 - Test Review Flashcards
How much of the spinal cord is supplied by the anterior spinal artery?
How much is supplied by the posterior spinal arteries?
The anterior 2/3
The posterior 1/3
The posterior spinal arteries supply which portion(s) of the spinal cord?
Dorsal columns
The anterior spinal arteries supply which portion(s) of the spinal cord?
Corticospinal tracts, spinothalamics, etc.
(basically everything but the dorsal columns)
Name the major artery that assists the anterior spinal artery in perfusing the lower half of the spinal cord.
Artery of Adamkiewicz
(arteria radicularis magna)
The artery of Adamkiewicz (arteria radicularis magna) comes off which artery at which level?
A posterior intercostal artery in the thoracic region
Which arteries perfuse the internal capsule (carrying fibers between the cortex and brainstem)?
(They arise from which bilateral, major arteries?)
The lenticulostriate arteries
(from the middle cerebral arteries)
What is the purpose of the internal capsule?
To connect cortical afferents and efferents to the midbrain
(passing between and interacting with the basal ganglia)
True/False.
Strokes involving the lenticulostriate arteries often result in motor and sensory deficits.
True.
(due to infarction of the internal capsule)
Describe the somatotropic make-up of the internal capsule (from an axial view).
Acute inflammatory demyelinating polyradiculopathy typically results in _________ motor neuron symptoms.
Acute inflammatory demyelinating polyradiculopathy typically results in lower motor neuron symptoms.
Partial myelitis typically results in _________ motor neuron symptoms.
Partial myelitis typically results in upper motor neuron symptoms.
Which of the following is associated with upper motor neuron symptoms?
Acute inflammatory demyelinating polyradiculopathy
Partial myelitis
Partial myelitis
______________ is the most common incomplete spinal cord injury syndrome
Central cord syndrome is the most common incomplete spinal cord injury syndrome
How does central cord syndrome of the cervical syndrome typically present?
Weakened limbs with upper limbs being weaker than lower limbs
(variable sensory loss)
True/False
Central cord syndrome has a fairly strong association with syringomyelia (syrinx).
True.
What are the S/Sy of the spinal cord damage seen in severe, prolonged vitamin B12 deficiency?
Subacute combined degeneration
Diminished vibration, touch, and proprioception;
UMN symptoms;
paresthesias
Which portions of the spinal cord are damaged in tabes dorsalis (neurosyphilis)?
The dorsal columns and roots
What is the spinal shock syndrome sometimes seen following a traumatic transection of the spinal cord?
A gradual recovery of reflex (from areflexia or hyporeflexia)
(although motor and sensory function remain lost)
D____________ (a lack of coordination leading to under- or overshooting in fine motor movements) and D____________ (impairment of alternating movements) are both associated with cerebellar dysfunction.
Dysmetria (a lack of coordination leading to under- or overshooting in fine motor movements) and Dysdiadochokinsia (impairment of alternating movements) are both associated with cerebellar dysfunction.
All motor cranial nerve nuclei except the lower face and genioglossus receive corticobulbar input from which laterality (i.e. does the cortex send UMN fibers ipsilaterally or contralaterally to synapse in the cranial nuclei)?
Ipsilateral and contralateral
Which musculature does not receive both ipsilateral and contralateral input from the corticobulbar tracts?
The lower face
+
the genioglossus
The lower face and genioglossus receive only _____lateral corticobulbar input.
The lower face and genioglossus receive only contralateral corticobulbar input.
Lesions of the upper motor neurons (corticobulbar neurons) innervating the motor nuclei of CN VII will lead to what sort of S/Sy?
(Portion(s) of the face and laterality(ies))
Contralateral paralysis of the lower face
Lesions of the CN VII lower motor neurons will lead to what sort of S/Sy?
(Portion(s) of the face and laterality(ies))
Ipsilateral paralysis of the upper and lower face
Why can’t the eye close in cases of CN VII palsy?
Orbicularis oculi paralysis
Bell’s palsy is an older eponym referring to ___________ CN VII palsy, but we now know that most cases are caused by ___________.
Bell’s palsy is an older eponym referring to idiopathic CN VII palsy, but we now know that most cases are caused by HHSV.
Name some causes of isolated CN VI palsy.
DM, stroke, increased ICP, etc.
While damaging CN VI will result in an ipsilateral loss of abduction, what happens when the CN VI nucleus is damaged?
Issues in both eyes (due to the MLF connection);
now neither eye will point towards the side of the lesion
Which nucleus contributes parasympathetics to CN III?
Edinger-Westphal
Does ALS affect UMNs or LMNs?
Both
Identify which (or both or neither) of the following do decussate:
CN VI
The medial longitudinal fasciculus
CN III
The medial longitudinal fasciculus
What effect does a lesion of the right medial longitudinal fasciculus have on eye movement?
Failure of left eye adduction in conjugate gaze with right eye abduction
Upon asking a patient to look to their left, their left eye abducts but their right eye remains pointing forward.
Where is the lesion likely to be?
The left medial longitudinal fasciculus
Neurons from what location innervate the abducens nuclei and subnuclei (the subnuclei control the MLF)?
The paramedian pontine reticular formation
What is the effect of a lesion in the PPRF (paramedian pontine reticular formation)?
Failure to abduct ipsilateral eye
A lesion of both the PPRF (paramedian pontine reticular formation) and also the ipsilateral medial longitudinal fasciculus will result in what?
Cannot abduct OR adduct ipsilateral eye or adduct contralateral eye
(‘one-and-a-half syndrome’)
