Term
|
Definition
activates m3 = contaction of circular mm = miosis
also activates m3 on ciliary mm = contraction |
|
|
Term
|
Definition
| activate alpha 1 R = contraction of radial mms = mydriasis |
|
|
Term
| innervation of ciliary mm is dominated by... |
|
Definition
|
|
Term
| need activation of m3 in ciliary mm, to contract ciliary mm and get fat bulging lens in... |
|
Definition
|
|
Term
| pupil accomodation reflex = |
|
Definition
as ciliary mm contracts, the pupil constricts (miosis) due to stim of PSNS activating m3 R on curcular mm and ciliary mm.
miosis as an object comes close to the eye |
|
|
Term
| if pupil narrows do you automatically get ciliary contraction? |
|
Definition
|
|
Term
|
Definition
| decr pupil size in response to light |
|
|
Term
| what innervation is dominant in ciliary body? |
|
Definition
|
|
Term
| what is the dominant post synaptic R in the ciliary body? |
|
Definition
|
|
Term
| SNS releases NA and activates beta 1 R in ciliary bosy = |
|
Definition
production of aqueous humour
(get basal production of aq humour due to symp tone) |
|
|
Term
| SNS releases NA and activates alpha 2 R in ciliary bosy = |
|
Definition
| decr aq humour production |
|
|
Term
| SNS releases NA and activate alpha 1 on bv = |
|
Definition
| vasoconstriction = derc BF = decr production of aq humour |
|
|
Term
| incr carbonic anhydrase = |
|
Definition
| incr HCO3- = incr arte of aq humour production |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
...aid ocular exam
...prevent synechiae (adhesion of iris to another part of the eye) |
|
|
Term
|
Definition
muscarinic R antagonists
alpha 1 R agonists or NA displacing agent |
|
|
Term
| name 3 muscarinic antagonists |
|
Definition
atropine
cyclopentolate
tropicamide
(in order of most to leats potent) |
|
|
Term
| muscarinic antagonists side effect = |
|
Definition
| cycloplegic effects = loss of accomodation :( |
|
|
Term
| why isnt atropine used clinically as a mydriatic? |
|
Definition
| due to its hits duration of action (160-240hrs) |
|
|
Term
| alpha 1 R agonists effect on dogs and cats = |
|
Definition
mydriasis in dogs
no effect on healthy cat eye |
|
|
Term
| advantage of alpha 1 agonist over muscarinic antagonists (which are more effective) = |
|
Definition
| no effect on accomodation :) |
|
|
Term
| alpha 1 R agonists clinical use = |
|
Definition
| tx horners syndrome in dogs and cats |
|
|
Term
|
Definition
disruption of SNS input and PSNS domination
droopy eye
miosis
prominant thrid eyelid |
|
|
Term
|
Definition
|
|
Term
|
Definition
| impairement of drainage of aq humour = high intraocular press |
|
|
Term
| name 4 drugs used to tx glaucoma |
|
Definition
1. miotics
2. CA inhibitors
3. beta blockers
4. osmotic agents (for emrgencies) |
|
|
Term
|
Definition
| direct muscarinic agonists = activate m3 = activate contraction of circular mms = miosis = incr drainage of aq humour |
|
|
Term
| side effect with miotics = |
|
Definition
| loss of accomodation as activates m3R on ciliary mm |
|
|
Term
|
Definition
pilocarpine
carbachol (longer lasting) |
|
|
Term
| miotics are contraindicated... |
|
Definition
| ...if got anterior uveitis or anterior lens luxation (as these both block drainage) |
|
|
Term
|
Definition
| inhibit production of aqueous humour |
|
|
Term
|
Definition
acetazolamide
dichlorphenamide |
|
|
Term
|
Definition
oral
IV in emergencies (problem = more side effects as decr HCO3- throughout the body) |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| what other effect does dichlorphenamide have? |
|
Definition
|
|
Term
|
Definition
| inhibit beta 1 R = inhibit aq humour priduction |
|
|
Term
|
Definition
|
|
Term
|
Definition
timolol
betaxolol
carteolol
metipranolol |
|
|
Term
| emergency tx of glaucoma if... |
|
Definition
| ...pupil block (pupil not responding to drugs due to anterior or posterior synechiae-lens displacement) |
|
|
Term
| for emergency tx of glaucoma use ... |
|
Definition
...hyperosmotic agents - glycerol (oral) or mannitol (IV)
often with acetazolamine (CA inhibitor) - IV |
|
|
Term
| keratoconjunctivitis sicca = |
|
Definition
| keratinised (opaque), inflammed and dry cornea |
|
|
Term
| keratoconjunctivitis sicca = |
|
Definition
| keratinised (opaque), inflammed and dry cornea |
|
|
Term
| keratoconjunctivitis sicca is common in... |
|
Definition
|
|
Term
| keratoconjunctivitis sicca is characterised by... |
|
Definition
| ...thick yellow dicharge and usually effects both eyes |
|
|
Term
| causes of keratoconjunctivitis sicca = |
|
Definition
| tear deficiency = persistant conjunctivitis and corneal ulceration and scarring due to no lubrication |
|
|
Term
| tx of keratoconjunctivitis sicca = |
|
Definition
1. improve/replace tear secretions
2. surgery (transplant salivary duct from mouth to eye) - last resort
3. topical corticosteroids to supress inflam
4. topical antibacterials (in case of secondary infections) |
|
|
Term
| can improve tear sceretion with what drugs? |
|
Definition
| cyclosporin (immunosupressant) pilocarpine (miotic drug =muscarinc R agonist) |
|
|
Term
|
Definition
|
|
Term
| with cyclosporin tx see improvement within... |
|
Definition
| ...10days, but sometimes can take up to 6wks! |
|
|
Term
|
Definition
retards immune mediated destruction of tear glands
controls pigmentary keartitis |
|
|
Term
|
Definition
|
|
Term
|
Definition
| muscarinic R agonist = stim tear production from lachrimal glands if any function left! |
|
|
Term
| pilocarpine is only effective if... |
|
Definition
| ...sufficient tear tissue is left and there are sufficient m3 Rs to be activated |
|
|
Term
| replacement of tear seceretion involves the use of... |
|
Definition
...eye drops containing either
hypromellose
liquid paraffin
polyvinyl alcohol
carbomers |
|
|
