Retina and Vitreous Vol. 3

Question 1

How is fluorescein eliminated from the body following FA?

Answer 1

By the liver and as well as the kidneys via the urine

Question 2

How long does it take to remove fluorescein from the body following FA?

Answer 2

24 to 36 hours

Question 3

What percentage of fluorescein injected during FA is protein bound and can NOT be visualized during the study?

Answer 3

Approx. 80%

Question 4

What form of fluorescein is visualized during FA?

Answer 4

Non-bound fluorescein (20%)

Question 5

What is the wavelength of light emitted by fluorescein?

Answer 5

520-530 nm {green)

Question 6

What wavelength of light excites fluorescein?

Answer 6

465-490 nm {blue)

Question 7

What type of filter blocks reflected blue light and allows only green light to re-enter the camera during FA?

Answer 7

Yellow-green filter (e.g. barrier)

Question 8

What prevents non-bound fluorescein from reaching the neurosensory retina or subretinal space?

Answer 8

RPE

Question 9

What structures provide the inner blood-retina barrier?

Answer 9

Endothelial cell tight junctions

Question 10

When does fluorescein enter the ocular circulation following injection?

Answer 10

Approximately 8 to 12 seconds after injection

Question 11

When does the arteriovenous phase of FA begin following injection?

Answer 11

Approximately one minute after injection

Question 12

What is considered to be the peak phase of fluorescence during FA when foveal detail is the greatest?

Answer 12

Arteriovenous phase

Question 13

What causes of leakage of capillary vessels on FA in diabetic retinopathy?

Answer 13

Damaged capillary endothelium

Question 14

Name 4 things that cause staining on FA.

Answer 14

1. Scar 2. Drusen 3. Optic nerve tissue 4.Sclera

Question 15

When is transmission or window defect seen during FA?

Answer 15

During choroidal filling

Question 16

How long does temporary yellowing of the skin and conjunctiva last after FA?

Answer 16

6 to 12 hours

Question 17

How long does discoloration of the urine last after FA?

Answer 17

24 to 36 hours

Question 18

What is the incidence of nausea, vomiting, or vasovagal reaction with FA?

Answer 18

Approx.10%

Question 19

What is the incidence of urticarial {anaphylactoid) reactions due to FA?

Answer 19

Approx.1%

Question 20

What is the incidence of anaphylactic reaction (cardiovascular shock} due to FA?

Answer 20

< 1 in 100,000

Question 21

What premedication can decrease risk of urticarial reaction due to dye can help decrease risk of reaction on subsequent FA?

Answer 21

Antihistamines and/or corticosteroids

Question 22

What treatment should be used if dye extravates into the skin, causing local pain during FA injection?

Answer 22

Ice-cold compresses

Question 23

What is indocyanine green (ICG) angiography particularly useful in studying?

Answer 23

Choroidal circulation

Question 24

How is indocyanine green metabolized?

Answer 24

Metabolized by the liver and excreted in the bile

Question 25

What is the fluorescence wavelength of indocyanine green?

Answer 25

790-805 nm (eg.near-infrared)

Question 26

What medication should ICG angiography be avoided if the patient is taking?

Answer 26

Metformin

Question 27

What two molecules make up A2E?

Answer 27

Vitamin A aldehyde and ethanolamine

Question 28

What do plaques on ICG angiography typically indicate?

Answer 28

Occult CNV (eg.late-staining vessels)

Question 29

What two conditions are focal hot spots on ICG angiography typically indicative of?

Answer 29

1. Retinal angiomatous proliferations (RAP) 2.Polypoidal vasculopathy

Question 30

What allergy should be asked about prior to performing ICG angiography?

Answer 30

Iodine or shellfish

Question 31

Name 2 contraindications of ICG angiography.

Answer 31

1. Liver disease 2. Metformin use

Question 32

What creates lipofuscin?

Answer 32

Phagocytosis of photoreceptor outer segments by RPE cells

Question 33

What pigment within lipofuscin causes autofluorescence?

Answer 33

A2E