Glaucoma Flashcards
What are the two types of glaucoma?
Acute angle closure glaucoma
Primary open angle glaucoma
What is acute angle closure glaucoma?
An acute rise in intraocular pressure associated with narrowing of the anterior chamber angle of the eye (the angle between the iris and cornea) causing optic nerve damage.
What are some risk factors for AACG
Increasing age - 6th and 7th decade
Female
Asian ethnicity
Family history
Anatomical predisposition - short eyeball, long sighted hypermetropia
Mid dilation of the pupil - dark room or medications (atropine - pupil dilating drop)
What is the usual presenting complaint of someone with AACG
Painful red eye
Headache, nausea and vomiting
Visual changes - blurred vision and haloes around lights
Describe the typical clinical findings of AACG
Unilateral red eye
Fixed mid-dilating pupil
Corneal haze due to oedema in the cornea
Eyeball is hard to touch
What are the differentials of someone presenting with a painful red eye?
Episcleritis
Keratitis
Conjunctivitis
Anterior uveitis
What are the investigations for AACG
Gonioscopy - Assess angle between iris and cornea
Tonometry - measure IOP
What is the typical pressure on tonometry in AACG?
> 30mmHg
What is the management of AACG?
Emergency referral to ophthalmology - sight threatening
Reduce IOP - topical timolol (betablocker to decrease aqueous humour production), Topical pilocarpine (Miotic that constricts the pupil and increases aqueous humour flow) and Oral or IV acetazolamide (carbonic anhydrase inhibitor to decrease aqueous humour production)
Surgical management - bilateral peripheral iridotomy
What is a peripheral iridotomy
Make a hole in the iris using a laser to improve aqueous humour outflow
What are the complications of AACG
Sight loss
Central retinal artery/vein occlusion
Repeated episodes of AACG
What is chronic open angle glaucoma?
A chronic condition which can cause damage to the optic nerve. People may not be aware they have it. Painless condition. Impaired drainage through the trabecular meshwork. Can have high/normal pressures
What are the RF for developing glaucoma
Afro-Caribbean
FH
Old
Short sighted
What are the symptoms of glaucoma?
Usually none in early stages
Eventually loss of peripheral vision although brain is good at making up for this visual loss so it is not noticed by the patient
How is glaucoma managed?
Regular reviews and pressure checks
Topical eye drops - beta blockers (decrease production) and prostaglandin analogue drops (increase drainage)
Tablets - decrease production of aqueous fluid
Surgery - trabeculectomy - creating a channel from front of eye just under conjunctiva so fluid can pass out and bypass trabecular network
