Glaucoma Flashcards
Glaucoma are a group of disorders characterised by progressive optic nerve damage and visual field loss.
Raised intraoccular pressure is prominent but not a diagnostic feature.
3 fundamental changes in glaucoma?
Increased IOP
Visual field defects
Optic disc cupping
How do you measure intraocular pressure?
Applanation tonometry
How do you test visual field defects?
Perimetry
How do you check for optic disc cupping?
Fundoscopy
What way do visual field defects start in glaucoma?
Typically Visual field defects start peripherally and progress in a crescent shape.
What is the normal cup to disc ratio and what signifies glaucoma?
0.4-0.7, a cup to disc ratio of > 0.7 suggests glaucoma.
What are the 2 first line drugs in glaucoma and what are the side effects?
1) Latanoprost (PGL analogue) changes colour of iris and thickens eyelashes.
2) Timolol (beta blocker) causes dry eyes, caution in asthmatics.
Side effect of carbonic anhydrase inhibitors?
They cause peri oral tingling and paraestheia.
How do prostaglandins analogues work?
Increase draining of aqueous humour by increased uveoscleral outflow.
How do the rest of the glaucoma drugs work?
They reduce the production of aqueous humour.
How does chronic open angle glaucoma present?
Typically asymptomatic.
Usually picked up ast optician by:
- raised IOP
- Visual field defect
- Optic disc cupping
If a person with open angle glaucoma is symptomatic, what do they complain of?
Loss of peripheral vision
Surgery for open ngle glaucoma?
Trabeculectomy.
Presentation of acute closed angle glaucoma?
Sudden onset painful red eye with reduced visual acuity, blurring of vision,. Haloes around light and assoc headache, N&V
