Retina and Vision

What is the retinal signal pathway?

Light enters and passes through the retinal epithelium the goes to the photoreceptors aka rods and cones, then goes to bipolar cells, ganglion cells, then the optic nerve

What signal pathway is shown?

The retinal signal pathway

What pathway is being shown in this figure?

The light pathway (how light enters the eye)

What are the rods?

Photoreceptors that are long and skinny, very sensitive to light, helps with peripheral and night vision. NO COLOR MAINLY LIGHT IN THE DARK, 120 million so a lot

What structure is crossed out in blue? What is its importance?

This is the fovea which is the area of highest visual acuity, only cones no rods

What structure is crossed out in black?

This is the optic disc which is the area known as our blind spot

What are the cones?

Photoreceptors that are mainly for color and high acuity, RGB colors, concentrated at fovea, 6 million

What is the Fovea centralis

The center of the macula, location of highest acuity. NO RODS ONLY CONES

What is the macula lutea

Yellow spot lateral to optic disc, responsible for central vision

Optic disc? Amount of vision?

Where CN 2 and central artery exit, blind spot/no vision because it has no photo receptors

What is the ora serreta?

the boundary between the visual and non visual retina

What is RPE?

The retinal pigmented epithelium, pigmented in order to understand light, adjacent to choroid, blood retinal barrier

What are the RPE cells and what is their key function? Location?

These are cells that contain melanin which absorbs scattered light that passes through photoreceptors, located between the photoreceptors and the choroid

What is the function of the choroid?

To nourish the eye by supplying oxygen and nutrients to the outer retina aka the photoreceptors.

If the choroid supplies the outer retina, what supplies the inner retina?

The central retinal artery

What does the choroid contain/what is its relation to the RPE?

Contains melanocytes in its outermost layer, allowing it to be able to absorbs any last that passed the RPE entirely

What is importnat to note about the choroid?

It contains melanin and absorbs excess light

What would happen if there was central retinal artery occultation

It would cause inner retina schemia causing painless vision loss

What is the path of light?

Cornea which does 70% of refraction, the the aqueous humor, then the lens, then the vitreous humor, then the retina

What is the pnuemonic Can A Lens View A Retina

Oath of light aka cornea, aqueous humor, lens, vitreous humor, retina