acute angle closure glaucoma Flashcards
what is the pathophys of AACG?
iris buldges forward and seals of trabecular meshwork
aqueous humour can not drain and increases intraocular pressure
which way does the iris bulge and what is the effect?
bulges forward to seal trabecula meshwork form anterior and causes increases pressure in posterior
the posterior pushes iris forward and further exacerbates angle closure
how should AACG be managed and why?
medical emergency as it can cause permanent vision loss
what are RF for AACG?
age
family hx
female
chinese and east asian
shallow anterior chamber
how many more more times are females at risk than males for AACG?
4x more
why are east asians and chinese more likely to get AACG?
eye shape
what medications put you at risk of AACG?
adrenergic medications eg noradrenaline
anticholinergic - oxybutyunin
TCA - amitriptyline
how does AACG present?
general unwell
short Hx of severely painful eye, blurred vision, halos around lights, associated Headache and N+V
how does the eye appear on exam with AACG?
usually one eye
red
hazy - blurred over
decreased visual acuity
mid-dilated
fixed pupil
hard eyeball on palpation
in primary care how would you manage AACG?
call ambulance
lie on pillow flat
pilocarpine eye drops -2% blue eyes and 4% brown eyes
acetazomide 500mg oral
analgesia
antiemetic?
what is acetazolamide?
carbonic anhydrase inhib helps reduced aqueous humour
how does pilocarpine work?
acts on muscarinic receptors in sphincter muscles on iris to cause pupil constriction
- causes ciliary muscle contraction
- allows pathway for aqueous humour to flow around iris and trabecular meshwork
in secondary specialist care, what can be done to help AACG?
pilocarpine eyedrops
acetazolamide oral or IV
hyperosomotic agents
timolol
dorzolamide - carbonic inhib
brimonide - sympathomimetic
how does hyperosmotic agents work?
increase osmotic gradient between blood and eye
give an example of an hyperosmotic agent FOR AACG?
IV mannitol
