20 - Glaucoma Flashcards
glaucoma
disorders characterized by increased IOP
-leads to nerve atrophy + periph visual field loss
incidence of glaucoma increases w…
age
blindness fr glaucoma
largely preventable w early detection + proper treatment
angle
the place where the outflow occurs
-bc angle is where iris meats the cornea
primary open-angle glaucoma POAG
most common type
- outflow of aqueous humor is decr in trabecular meshwork
- drainage becomes clogged
angle-closure glaucoma (ACG)
due to reduction in outflow of aqueous humor fr angle closure
ACG possible causes
- caused by lens bulging forward due to aging
- pupil dilation in pt w anatomically narrow angles
ACUTE angle-closure glaucoma
precipitated by situations in which pupils stay partially dilated long enough to cause an acute + rise in IOP
ACUTE angle-closure glaucoma possible causes
- drug-induced mydriasis
- emotional excitement
- darkness
POAG manifestations
- slow w/o pain or pressure
- tunnel vision w only small center field
- peripheral vision is absent
Acute ACG manifestations
- sudden + severe pain in or around eye
- n/v
- colored halos around lights
- blurred vision
- ocular redness
subacute/chronic ACG manifestations
- gradual
- blurred vision
- seeing colored halos around lights
- ocular redness
- eye or brow pain
Normal glaucoma pressure
10-21 mmHg
POAG pressure
22-32 mmHg
AACG
> 50 mmHg
POAG + slit lamp microscopy diagnostic
norm angle
AACG + slit lamp microscopy diagnostic
either more narrow angle or flat anterior chamber angle
- edematous cornea
- fixed moderately dilated pupil
in ACG, central visual acuity is reduced if..
pt has cornea edema
___ may be the first sign of chronic POAG
optic disc cupping
wider, deeper, paler
drug therapy for chronic open angle glaucoma
B-adrenergic blocker [betaxolol]
B adrenergic blocking glaucoma is CI w…
- bradycardia
- heart blog greatehr than 1 degree
- cardiogenic shock, HF
noncardioselective B adrenergic blockers are CI in…
copd or asthma
argon laser trabeculoplasty
noninvasive way to lower IOP when meqds are not successful
-laser stim scarring + contractn of trabecular meshwork» opens outflow channels
trabeculectomy or filtration surgery
if med or laser therapy is not succesful
laser peripheral iridotomy or surgical iridectomy
necessary for long-term tx + preventn of more episodes
-allows aqueous humor to flow thru a NEWLY CREATED OPENING IN IRIS into outflow channels
glaucoma screening
40-65 yo: Q2-4yr
65+ yo: Q1-2yr
more often for black
