Glaucoma Flashcards
What is a typical presentation of open angle glaucoma?
65 year old lady reading book at night, sudden loss of vision, headache, and nausea
How to assess pressure in the eyes without a device?
press on eye balls- should feel slight squidgy and not solid as a rock. there should be no difference between the two eyeballs. if one feels rigid compared to the other than concern
What are the triad of features in glaucoma
raised intraocular pressure
optic nerve changes
visual field loss
What is open angle glaucoma?
optic nerve damage that is caused by a rise in intraocular pressure
What causes a rise in introcular pressure in glaucoma?
blockage of aqueous humour trying to escape the eye (aqueous humour= proximal compartment of eye/anterior chamber, vitreous humour distal compartment)
WHat is the direction of travel of aqueous humour?
flows from ciliary body, around lens and under iris, through anterior chamber, through the trabecular meshwork and into canal of schlemn, from where it then enters general circulation
Which glaucoma is an emergency and why?
acute angle closure glaucoma. iris bulges forward and seals off trabecular meshwork from the anterior chamber preventing aqueous humour from being able to drain away, causing cupping of the optic disc
Risk factors for glaucoma?
increasing age
family history
myopia= short sightedness (smaller eye?)
black ethnic origin
Which vision does glaucoma affect?
peripheral vision- tunnel vision
How is glaucoma diagnosed?
goldmann tonometry- measures intraocular pressure
fundoscopy
visual field assessment
What is the management of open angle glaucoma?
prostaglanding analogue eye drops
beta blockers- reduce production of aqueous humour
carbonic anhydrase inhibitors- reduce production of aqueous humour
Surgery- trabeculectomy
What is the difference between open and closed glaucoma?
In open-angle glaucoma, the iris is in the right position, and the uveoscleral drainage canals are clear. But the trabecular meshwork isn’t draining properly. In closed-angle glaucoma, the iris is squeezed against the cornea, blocking the uveoscleral drains and the trabecular meshwork
What is the normal intraocular pressure?
10-21 mmHg
Name a prostaglandin analogue
latanoprost
Name one side effect of latanoprost?
eyelash length, iris pigmentation and periocular pigmentation
