week 2: Angle closure Flashcards
T/F: the iris rests on the lens?
False, there is about a 5 um space bw them
what is relative pupillary block?
flow of aqueous from the posterior chamber through the pupil is impeded (blockage in path bw iris and lens) and obstruction creates a pressure gradient between the posterior and anterior chambers, causing the peripheral iris to bow forward against the trabecular meshwork
Risk factors for relative pupillary block? (or just angle closure?)
1) older age:60-70
2) women (have shallower ACs)-except for african americans
3) fam hx
4) hyperopic eyes
5) small cornea and winter (low light)
avg adult eye chamber depth:
- 15 mm
* at risk for closure if 2.0 mm or less
T/F: pupillary block can frequently happen not immediately after dilation but later when drops are wearing off and the pupil is mid dilation
true
4 categories of angle closure:
1) primary angle closure suspect
2) primary angle closure
3) primary angle closure glaucoma
4) acute angle crisis glaucoma
what classifies someone as primary angle closure suspect:
180 degrees or more of iridotrabecular contact on gonio in primary gaze (IOP is normal, optic nerve normal, no PAS)
what classifies someone as primary angle closure vs just a suspect:
180 degrees or more of iridotrabecular contact on gonio in primary gaze but there is harm being done to eye normal nerves and field but PAS and or elevated IOP
what classifies someone as primary angle closure glaucoma vs just a PAC:
180 degrees or more of iridotrabecular contact on gonio in primary gaze but there is harm being done to eye: glaucomatous fields and nerves
outcome so far of ZAP study:
LPI done in one eye is effective but only for about 6 months (but still better than no LPI in fellow eye)
in acute angle closure glaucoma, pupils will be:
mid dilated
describe the AC depth, angle depth and bilaterality of Pupil Block
narrow angle, shallow axial depth, bilateral, iris bombe (bows)
describe the AC depth, angle depth and bilaterality of plateau iris:
narrow angle, depth relatively normal, bilateral, plateau appearance on gonio
describe the AC depth, angle depth and bilaterality of malignant
flat chamber, narrow angle, unilateral
which laser do you use for LPI?
YAG works better for light eyes, but most docs just do both (argon then YAG)
what 3 gtts do you give pre LPI?
proparacaine
pilo
apraclonidine or brimonidine (to avoid IOP spike after)
what gtt do you give after LPI?
pred forte 4X a day for several days (+glaucoma meds if they need or take them)
what is glaukomflecken?
infarction of ant lens epithelium from high IOP
name 3 examples in the eye that indicate previous angle closure attacks:
1) peripheral ant synechiae
2) glaukomflecken
3) iris atrophy
what is subacute angle closure glaucoma?
older classification: subacute/intermittent
Recurrent attacks- small
Dim lighting leads to pupil dilation and block
-PAS, particularly superiorly
-IOP often normal in office but angle very narrow
what kind of questions should you ask someone you suspect has subacute angle closure?
Blurred vision, halos around lights, eye pain, HA, eye redness
most common type of primary angle closure?
chronic
what symptoms do you get with chronic primary angle closure?
asymptomatic
2 types of plateau iris:
1) plateau iris configuration
2) plateau iris syndrome
