Ophthalmology - OPEN ANGLE GLAUCOMA Flashcards
What is the pathology of open angle glaucoma? [4]
There is a gradual increase in resistance through the trabecular meshwork.
Causing difficulty for flow of aqueous humour to exit the eye.
This causes the pressure to gradually increase.
What does increased pressure in the eye do to the optic disc?
Causes cupping
What is an abormal size of optic cup?
Diameter larger than 5mm (0.5cm)
What are the risk factors for Open Angle Glaucoma?
- Increasing age
- Family History
- Black Ethnicity
- Myopia (near-sightedness)
What part of the visual field is affected by glaucoma, and what can it progress to? [2]
Peripheral vision is affected.
Gradually closes until the patient experiences tunnel vision.
What are the two methods for measuring intraocular pressure? [2]
- Non-contact Tonometry
- Goldmann applanation tonometry
What tests can we do to diagnose glaucoma? [3]
- Goldmann Applanation tonometry
- Fundoscopy
- Visual Field Assessment
At what intraocular pressure woukd you start treament for glaucoma? [1]
24 mmHg or above
What is the first line treatment for glaucoma and how does it function? [2]
Prostaglandin Analogue eyedrops (latanoprost).
These increase uveoscleral outflow.
What are some side-effects of prostaglandin analogue eyedrops? [3]
- Eyelash growth
- Eyelid pigmentation
- Iris pigmentation
Give an example of a Beta Blocker that can be used in open angle glaucoma and how does it work? [2]
Timolol
Reduces the production of aqueous humour in the eye.
Give an example of a Carbonic Anhydrase Inhibitor that can be used in open angle glaucoma and how does it work? [2]
Dorzolamide
Reduces the production of aqueous humour in the eye.
Give an example of a Sympathomimetic that can be used in open angle glaucoma and how does it work? [3]
Brimonidine
Reduces production of aqueous humour and increases uveoscleral outflow
What is the name of the surgery that may be offered to patients with open angle glaucoma when eyedrops are inefective? [1]
Trabeculectomy
When is a trabeculectomy necessary for patients with open angle glaucoma? [1]
When eye drops are ineffective
