(41A) Eval of Vision Loss Flashcards
transient vision loss in both eyes simultaneously , think
basilar artery insufficiency
what are amaurosis fugax?
unilateral transient loss in vision for 5 to 10 mins due to TIAs
sudden loss of vision in one eye in an old person (>50), think?
in a young person?
old = arterial or venous occlusion
young = optic neuritis
the presence of RADP usually is assc with diseases of …
opitc N
chiasm
or optic tract anterior to the exit of the pupillary fibers
** widespread retinal dz = AV occlusive disease
+RAPD with normal appearing optic disc
optic neuritis
what does a +RAPD indicate
there is a difference in the optic nerve conduction on each side
*equal damage to both optic nerves will so NO RAPD
where must a lesion be found to cause scotoma in one eye
retinal or optic N
where must a lesion be found to cause homonymous hemianopsia
behind the chiasm (cortex)
where must a lesion be found to cause bitemporal hemianopsia
compression of the chiasm
retinal vascular lesions respect the ____ midline and optic nerve lesions the ____ midline
vascular = horizontal
optic N = central scotoma
young, middle age with sudden loss of vision in 1 eye + pain on motion of eye
optic neuritis
where is the visual field defect in a pt with optic neuritis
central (pts cannot see object when they look directly at it but can if they use their peripheral vision)
how is color vision affected in optic neuritis
red, color desaturation
scotomas move with the pts eyes or is fixed in the visual field
moves with the eyes
time course of optic neuritis
vision gets worse rapidly (10-14 days) and then slowly improves over 3 to 4 weeks
treatment of optic neuritis
GCS
optic disc appearance in retrobulbar ON and Papillitis
retrobulbar = optic disc nml papillitis = disc swollen
how does the presentation of papilledema compare to papillitis
papilledema: nml VA, enlarged blind spot, -/+RAPD
papillitis: dec VA, central scotoma, + RAPD
ON is frequently seen in …
MS
most common cause of a lesion to the optic chiasm
pituitary adenoma
homonymous hemianopsia, +RAPD, and optic atrophy
lesion between chiasm and LGN
homonymous hemianopsia, nml RAPD, and NO optic atrophy
lesion between LGN and cortex
location of lesions causing congruous vs incongruous homonymous hemianopsia
incongruous = more anterior congruous = posterior
etiology of congruous homonymous hemianopsia in a young pt vs old pt
young = tumor
old = stroke
(on opposite side of field defect!!!)
which CN might have a palsy with papilledema
6
is VA affected by papilledema
no
signs of papilledema
hyperemic and elevated disc blurred disc margins tortuous and dilated vessels hemorrhages spontaneous venous pulsations ABSENT
acute loss of vision in 1 eye in an older pt
+RADP
swollen and pale disc
altitudinal hemianopsia
ischemic optic neuropathy
**looks similar to ON but in older pts
“cherry red spot” appearance of macula
central retinal artery occlusion
are optic cups large or small with optic atrophy
large
asymptomatic damage to the head of the optic nerve secondary to inc ICP
chronic open angle glaucoma
what visual field defect is seen in open angle glaucoma
peripheral then central vision loss
