The Eye and Glaucoma Flashcards
Circular muscle ennervation by which system?
Parasympathetic system (M3 receptor)
Effect of ennervation of circular muscle
Contration-miosis-smaller pupil
Stimulus of circular muscle
Bright light
Stimulus of radial muscle
dim light
Which nervous system stimulates the radial muscle?
Sympathetic system (alpha-1 receptors)
Effect of ennervation of radial muscle
Contracts-mydriasis-dilates/widens pupil
What type of vision is thin lens used for?
Distant vision
Lens ligaments linked to which muscle?
Ciliary muscle with basal tone
Effect of relaxed ciliary muscle
wide ring, ligaments in all directions, thin lens
Nervous system controlling distant vision-ciliary muscle
Sympathetic NS
What type of vision is the thick lens for?
Close vision
Effect of ciliary muscle fiber contraction
Smaller ring, less tension in lens, more gelatinous lens, fills more space, thicker lens
Which nervous system controls close vision focus?
Parasympathetic NS
Glaucoma is induced by?
Increased intraocular pressure
Effect of beta blockers on lens
Thick lens, free passage of fluids to drainage channels
