Disorders Flashcards
Multiple Sclerosis
chronic demyelinating disease of the CNS
sx: paralysis due to sensory and motor axon disruption
Guillan-Barre Syndrome
acute demyelinating disease of the PNS
sx: decreases senses and motor coordination
Hyperkalemic periodic paralysis
episodes of weakness and low muscle tone due to inability to fire action potentials bc of incr in K+
Myotonia
Cl- channel abnormality causing difficulty relaxing muscles
Thomsen’s disease and Becker’s disease
channelopathy causing slow relaxation after sudden contraction
Myasthenia gravis
autoimmune disease producing Abs against AchR at the NMJ causing muscle weakness
tx: AchE inhibitors
Syringomyelia
damage to crossing fibers around the central canal
Retinitis Pigmentosa
Rhodopsin mutation causes rod degeneration –> less secretion of proteins req for cones –> cones degeneration –> progressive constriction of visual field
Usher’s syndrome
retinitis pigmentosum + hearing loss
Achromatopsia
mutated transducin or CNG ion channel –> cones unable to hyperpolarize in response to light
severe photophobia due to rod saturation
Primary open angle gluacoma
chronic obstruction of drainage system in eye –> incr IOP due to fluid buildup –> damage option n. –> vision loss
Angle Closure Glaucoma
acute narrowing of angle btwn cornea and iris –> block drainage of aq humor –> incr IOP–> vision loss
cataracts
opacification of lens with age
trigeminal neuralgia (tic douloureux)
recurrent episodes of excruciation pain provoked by certain trigger points in V2/V3 territory
Temporomandibular joint disorder
chronic pain of jaw, mastication mm. recurrent HAs, ear pain
Cerebral achromatopsia
damage to V4 : sudden impairment in color perception
cerebral akinetopsia
bilateral damange to v5/MT : sudden impairmnet in ability to detect motion (“freeze frames”)
Marcus Gunn Pupil
afferent/sensory pupillary defect : no resp in either eye in response to pupil light reflex
Argyll Robertson Pupil
Accommodation Reflex Rresent but Pupillary Reflex Absent
Benign Paroxysmal Positional Vertigo (BPPV)
posterior canal canalithiasis = activated by otoconia (crystal detached from utricle/saccule and collected in the semicircular canals)
diag: nystagmus towards the affected side during dix-hallpike test
Superior Canal Dehiscence
loss of bone covering the superior canal causing easy excitation by stimuli and dizziness from sounds
Labyrinthitis
loss of vestibular function in all canals due to inflammation in inner ear
sx: unilateral weakness and hearing loss
vestibular neuronitis
loss of vestibular function in canals but without hearing loss
sx: nystagmus to unaffected side, motion sensitivity, vertigo
meniere’s disease
inner ear fluid imbalance causing episodic vertigo and fluctuating hearing , tinnitus, aural fullness
