Ch 7: Clinical Correlates pg 181-184

Question 1

a total loss of rods will cause…

Answer 1

night blindness

Question 2

a total loss of cones will cause…

Answer 2

blindness

Question 3

a significant decrease in dietary vitamin A can cause…

Answer 3

night blindness

Question 4

colorblindness is more common is males or females?

Answer 4

males (red and green on single X chromosome, blue is on chromosome 7)

Question 5

increases in intracranial CSF pressure at the optic disk can cause…

Answer 5

papilledema (swelling at of nerve at the disk), and engorged retinal veins

*due to reduced axoplasmic flow in optic nerves

Question 6

when there is separation of the pigment epithelium from the outer segments of the photoreceptors this is called…

Answer 6

detached retina (can be caused by trauma)

Question 7

a detached retina can result in…

Answer 7

degeneration of photoreceptors in this segment

Question 8

what is the most common cause of vision loss in the elderly?

Answer 8

age-related macular degeneration

Question 9

what causes age-related macular degeneration?

Answer 9

gradual disappearance of the pigment epithelium and then loss of photoreceptors in the area of the macula

Question 10

retinitis pigmentosa is a group of hereditary disorders during which….

Answer 10

there is a progressive visual loss caused by degeneration of photoreceptors

Question 11

which photoreceptors degenerate first is retinitis pigmentosa, and what symptoms result?

Answer 11

rods

loss of night vision and loss of peripheral vision

Question 12

in a patient with retinitis pigmentosa what can be seen when evaluating the eyes?

Answer 12

clumps of melanin near retinal blood vessels that have migrated into the pigment epithelium adjacent to the affected parts of the retina