Glaucoma Flashcards
What is the defintion of glaucoma?
increased intraocular pressure which results in damage to the retina and optic nerve
What is the epi of glaucoma?
second leading cause of blindness in adults (following age-related macular degeneration)
What are 2 main types of glaucoma?
open angle (90%) and angle closure glaucoma
What is the angle referred to?
is the iridocorneal angle: angle between the iris and cornea
What is the aetiology of open angle glaucoma?
- Iridocorneal angle unaffected
- Defect of the trabecular meshwork which slows down flow of aqueous humour
- Chronic
What are RF and epi for open angle glaucoma?
- > 40 y/o
- DM
- FHx
- African decent
What are symptoms of open angle glaucoma?
- Bilateral progressive (chronic) visual field loss)
- Peripheral to central
- Often asymptomatic
What investigations are done for open angle glaucoma?
- Tonometry
2. Fundoscopy
What does tonometry show in open angle glaucoma?
check elevated intraocular pressure (only raised in 40% of open angle so not needed for DDx) – may get IOP>21mmHg
What does fundoscopy show in open angle gluacoma?
increase in cupping of optic disc
What is the medical managment for open angle gluacoma?
- Prostaglandin anlaogues (latanoprost, travoprost) which increase aqueous humour outflow
- Topical beta blocker: decrease aqueous production at ciliary body
What do the prostoglandin analgoues do in open angle glaucoma?
increase aqueous humour outflow
What do the topical beta blockers do in open angle glaucoma?
decrease aqueous production at ciliary body
What is the surgical treatment for glaucoma?
Surgical trabeculectomy
What is closed angle glaucoma also known as?
acute angle closure glaucoma
What is the aeitology of closed angle glaucoma?
- Narrowing of iridocorneal angle, prevents aqueous flowing correctly into the trabecular meshwork
- MEDICAL EMERGENCY (acute)
What are RF for closed angle glaucoma?
- Old age
2. Mydriasis (drug-induced like anti-cholinergic e.g. atropine)
What are symptoms for closed angle glaucoma?
- Sudden onset
- Photophobia
- Eye redness
- Severe pain
- Headache
- N+V
What investigations are done for closed angle glaucoma?
- Tonometry
- Slit lamp
- Gonioscopy
- Fundoscopy
- Dilated pupil unresponsive to light on one eye
What does tonometry show in closed angle glaucoma?
IOP>21mmHg (30 in acute angle closure)
What does slit lamp show in closed angle glaucoma?
narrowing/closure or iridocorneal angle
What is gonioscopy?
gold standard test to assess the irdiocnreal angle is suspected angle closure glucaoma
What does fundoscopy show in closed angle gluacoma?
increase in cupping of optic disc
What is the management of closed angle gluacoma?
- Emergency: need to lower IOP immediately
- Topical beta blocker (timolol) decrease aqueous production
- Carbonic anhydrase inhibitor (acetazolamide): decreases aqueous production
- Ultimately need surgery to cure: high intensity laser treatment
What is an example of a carbonic anhydrase inhbitor?
acetazolamide
What does the topical beta blocker and carbonic anyhdrase inhibitor do in closed angle glaucoma?
decreases aqueous production
What are examples of prostaglandin analogue in open angle glaucoma?
- latanoprost
2. travoprost
