Sensory Day Flashcards
a lesion of the optic nerve would result in
ipsilateral monocular vision loss
a pituitary lesion affecting the optic chiasm would result in
bitemporal homonymous hemianopnia
(pituitary adenona, craniopharyngoma, ACA aneurysm)
a lesion of the optic nerve just outside the optic chiasm would result in
ipsilateral nasal hemianopnia
(internal carotid artery aneurysm)
Lesions to areas after the optic chiasm result in […]ocular and homonymous […]lateral deficits in vision
Lesions to areas after the optic chiasm result in [bi]ocular and homonymous [contra]lateral deficits in vision
What visual deficit results from lesion of the optic tract or lateral geniculate body?
Contralateral homonymous hemianopia
What visual deficit results from a lesion of Meyer’s loop?
Contralateral homonymous superior quadrantanopia
(temporal lesion, MCA occlusion)
What visual deficit results from lesion of the dorsal optic radiation?
Contralateral homonymous inferior quadrantanopia
(parietal lesion, MCA occlusion)
What visual deficit results from a lesion of primary visual cortex?
Contralateral homonymous hemianopia with macular sparing
(PCA occlusion)
What visual field defect is associated with Wernicke aphasia secondary to middle cerebral artery stroke?
Contralateral homonymous superior quadrantanopia
(temporal lobe defect)
Contralateral homonymous hemianopia is a visual deficit associated most commonly with an […] or with an […] lesion
optic tract
LGN
Contralateral homonymous inferior quadrantanopia is a visual deficit associated with lesion of the […] lobe
parietal
(MCA infarct)
Contralateral homonymous superior quadrantanopia is a visual deficit associated with lesion of the […] lobe
temporal
(MCA infarct)
describe the path of trabecular outflow
Ciliary body → posterior chamber → pupil → anterior chamber → trabecular meshwork → canal of Schlemm → episcleral vessels
trabecular outflow is increased by […] agonists
M3
(pilocarpine, carbachol)
papilledema
elevated optic disc with blurred margins
central retinal artery occlusion
“cherry red” fovea
optic neuritis
hypertensive retinopathy
micro aneurysms, hemorrhages, cotton wool spots
sudden, painless loss of vision that lasts for seconds to minutes and is followed by spontaneous recovery
amaurosis fugax
what causes amaurosis fugax and why is it important?
transient central retinal artery occlusion
caused by serious conditions like carotid stenosis, thrombosis, vasculitis.
Reduce CVD risk factors and treat temporal vasculitis with low dose corticosteroids.
noise induced hearing loss is caused by damage to [….] cells in the organ of Corti
sterociliated
noise induced hearing loss is characterized by loss of […] frequency hearing first
high
in the inner ear, the cochlea contains the […] membrane that vibrates secondary to sound waves
basilar
each […] leads to vibration at a specific location on the basilar membrane
frequency
(tonotopy)
low frequency noises are heard at the […] of the basilar membrane
apex
(wide and flexible)
high frequency noises are heard at the […] of the basilar membrane
base
(thin and rigid)
why does otosclerosis cause conductive hearing loss?
3 ossicles of the middle ear conduct and amplify sound from the tympanic membrane to the middle ear
If there is unilateral […] hearing loss, the Weber test localizes to the affected ear
conductive
If there is unilateral […] hearing loss, the Weber test localizes to the normal ear
sensorineural
If there is unilateral conductive hearing loss, the Rinne test demonstrates
Bone conduction > air conduction
in the Rinne test, the tuning fork in front of the ear tests […] conduction
air
in the Rinne test, the tuning fork on the mastoid tests […] conduction
bone
If there is unilateral sensorineural hearing loss, the Rinne test demonstrates
air conduction > bone condution
inherited inability to amplify sound due to bony overgrowth of the stapes
otosclerosis
Causes of […] hearing loss include damage to the cochlea, CN VIII, or central auditory connections
sensorineural
Causes of […] hearing loss include obstruction, otosclerosis, and otitis media
conductive
Episodic vertigo triggered by certain changes in the position of the head
benign paroxysmal peripheral vertigo
vertigo symptoms for seconds after change in head position
benign paroxysmal peripheral vertigo
brief vertigo precipitated by movements
normal examination
benign paroxysmal peripheral vertigo
high endolymphatic pressure-acute symptoms with rupture of membranous labyrinth
vertigo symptoms >20 min to a few hours
meniere’s
intense vertigo lasting several hours associated with hearing loss
meniere’s
in peripheral vertigo, nystagmus [is/is not] suppressible with visual fixation
is
in central vertigo, nystagmus [is/is not] suppressible with visual fixation
is not
hearing loss or tinnitus ipsilateral to the vestibular lesion favors a […] lesion
peripheral
vertical or direction changing nystagmus indicates a […] lesion
central
Meniere’s triad
vertigo
sensorineural hearing loss
tinnitus
the uncus is the medial […] lobe
temporal
what is an uncal herniation?
mass effect caused by a supratentorial lesion → medial and downward displacement of the uncus at the tentorial incisure
findings consistent with central vertigo
vertical nystagmus
torsional or gaze evoked nystagmus
negative head impulse test
positive head impulse test suggests […] vertigo
peripheral
(corrective saccade following head turn)
negative head impulse test suggests […] vertigo
central
(eyes remained fixated while head is turned)
presbycusis is […] hearing loss
sensorineural
(AC>BC)
presbycusis is due to destruction of hair cells at the […] of the cochlea
base
(loss of high pitch hearing)
BPPV is provoked by observing […] on Dix-hallpike test
nystagmus
Endolymphatic hydrops, which results in endolymph accumulation within the membranous labyrinth, is the underlying mechanism of […]
meniere’s
What visual deficit results from lesion of the macula?
central scotoma
muscarinic antagonists can precipitate […] glaucoma
acute angle
(atropine)
a1 agonists can be used to treat […] angle glaucoma
open angle
(decreases aqueous humor production, but induces mydriasis so not for closed angle)
positional exacerbation is typical of […] vertigo
peripheral
(central is typically continuous, regardless of positional)
horizontal nystagmus is associated with […] vertigo
peripheral
(vertical with central)
