Vision Flashcards
What autonomic nerves innervate the cilliary muscle?
parasympathetics
What is the vascular layer of the eye?
Choroid
What is the blood supply to the retina?
inner layers: central retinal artery
outer layers: diffusion across the choroid
The rod pathway goes from rods to ______ then _______ and finally ________.
bipolar cells; amacrine cells; ganglion cells
The cone pathway goes from cones to _______ and then ________ .
bipolar cells; ganglion cells
What is the neurotransmitter for rods and cones?
glutamate
Amacrine cells neurotransmitters are _______ (excitatory/inhibitory).
inhibitory
Describe the parasympathetic innervation pathway of the eye.
begins at Edinger-Westphal nucleus, transmits via the third nerve to the ciliary ganglion -> short ciliary nerve to then the ciliary muscle (accomodation) and iris sphincter (miosis)
What are the parasympathetic functions of the eye?
accomodation and miosis
Describe the sympathetic innervation pathway of the eye.
T1 level to the sympathetic chain - > super cervical ganglion, continue to head up along the carotid artery, as long and short ciliary nerves to the iris radial fibers (mydriasis), Muller muscle of the eyelid, and weakly ciliary muscle
What are the sympathetic functions of the eye?
mydriasis and lid retraction
What are the characteristics of an Argyll-Robertson pupil?
intact accomodation reflex but no pupillary light reflex
What is the pathway of the light reflex?
impulses in retina > optic tract > pretectal nucleus > Edinger Westphal nucleus > third nerve > ciliary ganglion > short ciliary nerve > iris sphincter
What causes Horner syndrome?
impaired sympathetic output to the eye
What are the symptoms of Horner syndrome?
miosis, ptosis, anhidrosis, enophthalmos, dilated facial vessels
