EM Ophtha 7 Flashcards
____ eyes have higher risk of acute angle-closure glaucoma
Hypermetropic (farsighted) eyes, having a shorter anterior to posterior length, a flatter cornea, and a narrower angle
clinical features of acute angle-closure glaucoma
sudden painful vision loss
frontal or supraorbital headache
nausea and vomiting
fixed, midposition pupil
hazy cornea with conjunctival injection, most prominent at the LIMUS
rock hard eye
triad PE for acute glaucoma
cloudy corniea
fixed midposition pupil
rock-hard globe
carbonic anydrase inhibitors
ACETAZOLAMIDE 500 mg IV or PO, then 250 mg IV or PO 4 hours later,
max 1000 mg/day
BRINZOLAMIDE 0.5%, 1 drop, 3x daily
DORZOLAMIDE 2%, 1 drop, 3x daily
topical beta blockers
TIMOLOL 0.5%, 1 drop, 2x daily
BETAXOLOL 0.5%, 1 droip, 3x daily
topical a2-agonist
APRACLONIDINE, 1%, 1 drop 3x daily
BRIMONIDINE 0.2%, 1 droip, 3x daily
hyperosmotic agent
MANNITOL, 15% or 20% solution, 1.5-2 g/kg IV over 30 minutes
GLYCERINE, 1-2 g/kg/dose orally, repeat every 5 hours
remarks on pilocarpine
no longer recommended in the acute setting as cholinergic agents can paradoxically result in shallowing of the anterior chamber and further closure of chamber’s angle
other treatment modalities in glaucoma
for pain and vomiting:
FENTANYL
- also lowers LOC [whereas ondansetron has no effect on IOP]
Remarks on optic neuritis
visual loss is usally unilateral but can be bilateral
color vision is affected more commonly than visual acuity, and there may be visual field deficits
red desaturation test is helpful
can be idiopathic or an initial presentation of MULTIPLE SCLEROSIS
List of eye diseses with acute visual loss WITHOUT PAIN
- CRAO
- CRVO
- Retinal detachment
- Temporal arteritis
thinnest portion of the retina
macula
remarks re ophthalmic artery
first branch off the internal carotid artery
supplies the central retinal artery
CRAO: irreversible loss of visual function usually occurs after _______ of ischemia
4 hours
clinical features of CRVO
Loss of vision is variable, ranging from vague blurring to rapid, painless, and monocular loss of vision
fundoscopy:
“blood-and-thunder fundus”:
optic disk edema and diffuse retinal hemorrhages in all quadrants
CRVO vs papilledema vs optic neuritis
papilledema: bilateral optic disk edema (vs CRVO’s unilateral)
optic neuritis: peripheral retina is normal (vs CRVO’s diffuse retinall hemorrhages in all quadrants)
remarks on flashing lights and floaters
binocular complaints are almost always intracranial (i.e., ophthalmic migraines)
mocular complaints are almost alway related to the symptomatic eye
features of giantcell / temoral arteritis
headache
jaw claudication
fever, fatigue, myalgia, anorexia
temporal artery tenderness
ESR 70-100 mm/hour
CRP elevated
treament of giant cell arteritis
HIGH-DOSE CORTICOSTEROIDS
if no visual complaints:
PREDNISONE 60 mg OD, until ff up with ophtha within 1 week
with visual loss:
admit
high-dose IV methylprenisolone
500-1000 mg per day for 3 days
“Steroids should not be delayed while waiting for a temporal artery biopsy to be performed; however, biopsies whould be performed within 1 week of starting steroid therapy”
Tocilizumab is recommended for those resistant to or unable to take corticosteroids
acute cranial nerve III palsy with ipsilateral pupillary dilatation is ___________ until proven otherwise
posterior communicating artery aneurysm
normal optic nerve sheath measurements
adult: 5.0 mm in diameter
children: 4.5 mm
infants: 4.0 mm
*measured 3 mm posterior to the globe (US contrast is greatest at this point)
**values above threshold of 5.7 to 6.0 mm predicts intracranial pressure >20 mm
clinical features of CRAO
Sudden (occurring over seconds), profound, painless, monocular loss of vision - characteristic of CRAO
The event is often preceded by episodes of AMAUROSIS FUGAX (transient visual loss)
PE
afferent pupillary defect
pale retina
cherry red macula
management of CRAO
more recent studies support IV tissue plasminogen activator within 4.5 hours of symptom onset, however, ophthalmologists have not yet reached consensus on optimal management
there is no evidence supporting or refuting the success of maneuvers such as
- digital massage or
- intraocular pressure-lowering drugs or
- breathing into a paper bag to increase partial pressure of arterial CO2
management of CRVO
while no universally beneficial treatment exists, anti-vascular endothelial growth factor (anti-VEGF) and laser-induced chorioretinal anastomosis show promise
anti-VEGF eye medications
intravitreal
bevacizumab
ranibizumab
aflibercept
