Block 4 Review Flashcards
Horner syndrome can be caused by lesions found where?
brainstem tegmentum, and upper cervical cord that interrupt the sympathetic fibers descending to the IML of the
thoracolumbar cord.
Pancoast tumor at apex of lungs
Anisocoria
unequal pupil size
What is the pathological basis for anisocoria?
Pathology in sympathetic nervous system =
constricted pupil (miosis)
Stroke: Lateral medullary syndrome (Wallenberg
syndrome)
Pathology in parasympathetic nervous system = dilated pupil (mydriasis)
Argyll Robertson pupil
Compression: Tumors, uncal herniation,
aneurysm around CN 3
Weber’s syndrome, Benedikt’s syndrome
What are the common sources of diplopia?
Oculomotor palsy
Trochlear nerve palsy
Abducens palsy ± or lateral
gaze palsy
Double vision may result from what?
structural problems within the
orbit
disorders of extraocular
muscles
disorder of neuromuscular
junction
disorder of CN III, IV, VI
and/or their central pathways
Primary nociceptor reaction
Tissue damage in turn induces
low ECF pH, release of K+, ATP,
and synthesis of prostaglandins
(PG) and bradykinin (BK)
PG increases sensitivity
of pain terminals to BK and
other pain producing substances
What is secondary nociceptor induction?
primary nociceptor induction,
spreads to other branches
-Induce release of peptides (e.g.
Substance P, (SP)
Heat pain for mouth travels via what tract?
trigeminal thalmic tract
In pain modulation from central structures via peri-aqueductal gray PAG projects to what stucture in the brainstem?
NRM in rotstral medulla
What is a known endogenous substance causing nociceptor sensitization and therefore hyperalgesia?
Prostaglandin E
Relief of TP is through what?
antiepileptics
Valproate
carbamazepine
phenytoin
phenobarbital
and surgical intervention
What happens to muscles in diseases muscle myopathy?
number of muscle fibers in a motor unit is
reduced
What happens to muscles when the are denervated following nerve damage?
all muscle fibers in a motor unit become denervated and atrophic
In neurogenic diseases or myopathic diseases, the muscle is spontaneously active even at rest?
neurogenic
in neurogenic or myopathic disease there is no activity in the muscle at rest and no change in the number of motor units firing during contraction?
myopathic
Distal limb weakness indicates neurogenic or myopathy?
neurogenic disorder
Proximal limb weakness indicates neurogenic disorder or myopathy?
myopathy
Fibrillations are invisible or visible twitches of muscle?
invisible
Fasiclulations are visible or invisible twicthes of muscle?
visible
Clinical features of hypothyroid neuropathy.
Sensory and motor loss
High TSH low T4
Tiredness, hair loss, weakness, voice change,
menstrual changes, depression
Carpel tunnel syndrome
Slow axonal transport
Decreased tendon reflexes
What can present or what feelin can present in the body of those with B1 deficiency related peripheral neuropathy?
burning and pain in the calves
What is a chemotherapeutic agent that can cause toxic neuropathy?
vincristine
Vincrisitine symtpoms.
stocking glove tingling, then profound distal weakness and foot drop
MOA of vincristine.
inhibits microtubule polymerization and axonal transport
Duchenne muscular dystrophy pattern of inheritance.
x-linked recessive
Duchenne muscular dystrophy has what genetic basis?
Caused by mutation (commonly deletion) of gene encoding dystrophin
When is Duchenne muscular dystrophy present? (what age)
at birth; but manifest by ages 3 and 5
Limb-Girdle Muscular Dystrophy earliest presentation is between what years of life?
10-40 years
How is limb-girdle muscular dystrophy different than DMD?
intellectual function unaffected
What is inheritance pattern dystrophia myotonica?
AD DM1, DM2
What is myotonic dystrophy caused by?
trinucleotide repeat disorder
In DM1, affected gene - DMPK (myotonic
dystrophy protein kinase), codes for myosin
kinase.
How does myotonic dystrophy present?
muscle stiffness with myotonia and hair loss (alopecia)
Manifests in third and fourth
decade
cataracts frontal baldness testicular atrophy diabetes mellitus cardiac abnormalities intellectual changes
Lateral sclerosis in ALS result from what?
proliferation of astrocytes and
scarring of the lateral columns of spinal cord
Amyotrophic refers to what?
atrophy of muscle, weakness and fasciculation
How does riluzole work?
blocking TTX-sensitive sodium channels; This in turn reduces calcium influx and indirectly reduces glutamate receptor stimulation
glutamate receptor downregulator
Acute MS is characterized by what features?
plaques (lesions of varying sizes.
Disruption of BBB at sites of inflammation but vessel wall is
preserved
Demyelination through myelin specific autoantibodies
Cellular response:
Perivenular cuffing
Infiltration of inflammatory mononuclear cells (T- cells, macrophages and microglia cells that scavenge myelin debris)
Reactive astrocyte proliferation (gliosis)
Surviving oligodendrocytes attempt to remyelinate naked
axons thereby forming shadow plaques
Axonal sparing is typical, but partial or total loss may occur
Describe features of optic neuritis in MS.
Diminished monocular visual acuity, dimness and reduced perception of color
WHat is one major finding that can be assessed through MRI in a patient with MS?
shows multiple lestions (at white arrows) in anterior corpus callosum (usual in MS)
Another name for Neuromyelitis optica.
Devics disease
What is Devic’s disease
a subacute autoimmune disorder characterized by simultaneous or consecutive demyelination of optic nerve
& Spinal cord.
May be a distinct entity or variant of MS; monophasic or
recurrent disorder
