Lecture 3

Question 1

what 5 things do you examine for for the optic nerve?

Answer 1

disc size, margins, contour of rim tissue, C/D ratio and rim tissue and NFL

Question 2

what is a distinct margin?

Answer 2

easy to see the edges of the disc 360 - not uncommon for nasal to be indistinct and still be normal

Question 3

what is an indistinct margin?

Answer 3

unable to see the edges of the disc for the majority of the ONH diameter

Question 4

what is a normal and abnormal variation of an indistinct nerve?

Answer 4

normal = heaped up appearances or small congenital anomalous nerves
abnormal = papilledema

Question 5

what is a malinserted disc?

Answer 5

congenital - disc is tilted along the vertical axis (appears to tilt upward nasally and down temporal, often has a scleral crescent)

Question 6

what is a tilted disc?

Answer 6

congenital - the vertical axis is tilted, often downward nasally (often associated with tilted disc syndrome)

Question 7

what 3 things can cause papilledema?

Answer 7

increased ICP due to brain lesion, idiopathic intracranial hypertension, and hypertensive crisis (bilateral)

Question 8

what are 3 pseudopapilledemas (AKA congenital disc anomalies)?

Answer 8

optic nerve head drusen, congenitally full disc, and malinserted disc

Question 9

when looking at a the ONH - how do you know if there is papilledema vs. pseudopapilledema?

Answer 9

if swollen (papilledema) - the view of the vessels will be obscured (like looking through a cloud)

Question 10

what 5 signs point to papilledema?

Answer 10

indistinct margins, - SVP, + obscuration of vessels and hyperemic rim color

Question 11

what information does the contour or “type” of ON rim provide?

Answer 11

contour provides information of the neuroretinal rim tissue, also helps to look for notching for glaucoma and vessel deflection

Question 12

what are the 4 types of ONH contour?

Answer 12

flat, cylinder, slope/bowel, and hooked

Question 13

what is the C/D and physiological cupping typically for a type 1 nerve (flat)?

Answer 13

C/D = 0-0.2 
cupping = less than or equal to 1 diopter in depth

Question 14

what is the C/D and physiological cupping typically for a type 2 nerve (cylindrical)?

Answer 14

sharp temporal rim
C/D = 0.15-0.65
cupping = 1=5 diopters in depth

Question 15

what is the C/D and physiological cupping typically for a type 3 nerve (slope/bowel)?

Answer 15

C/D = 0.15-0.65+
cupping = 1-3 diopters in depth

Question 16

what is the C/D and physiological cupping typically for a type 4 nerve (hooked)?

Answer 16

C/D = 0.2-0.7+
cupping = 1-5 diopters in depth

Question 17

what is the ISN’T rule?

Answer 17

the inferior border should be the thickest > Superior > Nasal > Temporal (thinnest)

Question 18

how is the ISN’T rule helpful in glaucoma?

Answer 18

the vertical C/D increases faster than horizontal - doesn’t follow the ISN’T rule

Question 19

when judging the C/D, where do you measure the disc diameter from?

Answer 19

the first point of deflection of the disc vessels from the neural rim bending towards the optic cup - not color change

Question 20

what are the average C/D for Caucasians, African Americans and Asian/Latinos?

Answer 20

Caucasians = 0.4
African Americans = 0.6
Asian/Latinos = 0.5

Question 21

what is a normal amount of asymmetry between the two eyes C/D?

Answer 21

30% = 0.1 difference and 4% have a 0.2 difference

Question 22

what does a normal healthy, young NFL look like?

Answer 22

with red-free filter it should have a shimmering reflection

Question 23

what 4 things to you look for during retinal vessel evaluation?

Answer 23

A/V ratio, ALR, delfections or crossing defects, and area around the vessels (white, red, dark stuff)

Question 24

what is a normal A/V ratio and where do you look to compare?

Answer 24

normal = 2/3 or 3/4

estimation should be made after the first bifurcation and before the third

Question 25

what should you think if the veins are too wide? or arteries are too narrow?

Answer 25

veins too wide = think diabetes

arteries too narrow = HTN

Question 26

what is ALR?

Answer 26

arteriolar light reflex - ratio of the width of light being reflected off the surface of the artery to the overall width of the artery

Question 27

what is a normal ALR?

Answer 27

1/3 or 1/4

Question 28

what happens to the ALR with arteriosclerosis and HTN?

Answer 28

the ALR thickens - as the walls of the artery thicken, less light is allowed to pass through and more is reflected back

Question 29

what 4 things can happen to the vessel crossings with arteriolar sclerosis and HTN?

Answer 29

compression, deflection of the underlying vein, humping, and tapering (nicking)

Question 30

what are tortuous vessels?

Answer 30

vessels appear to be crooked or winding (if both vein and artery, usually congenital)

Question 31

what are the 5 fundus types?

Answer 31

albino, blonde, brunette, dark, and tigroid

Question 32

what is difference about an albino fundus?

Answer 32

there is no macular pigment (no RPE layer)

Question 33

what 5 things do you evaluate in the macula?

Answer 33

even pigmentation, foveal light reflex, hemorrhages, drusen, and pigmented lesions

Question 34

what is the foveal light reflex (FLR)?

Answer 34

a reflex actually located in the vitreous as a result of the shape of the retina and the “depression” of the fovea

Question 35

why is the FLR important to find?

Answer 35

if the patient has reduced acuities (20/25 or worse) you need to determine if the macula is the cause of reduction