Eye Investigations + Visual Defects

Question 1

What are investigations for the eye

Answer 1

Fluorescein Angiography
Optical Coherence tomography
ERG
EOG
VEP 
Open slit lamp
Fundoscopy

Question 2

What is fluorescein angiography

Answer 2

Retina impermeable to fluorescein
Choroid vessels are so look white
If there is leak in the retina will be able to detect

Question 3

When do you use

Answer 3

Neovascular macular degeneration suspected

GCA

Question 4

What does optical coherence tamography do

Answer 4

Scans the macula
See different layers of retina
Useful for macular and disc pathology

Question 5

What is your blind spot

Answer 5

Optic nerve

No photoreceptor cells

Question 6

What does ERG do

Answer 6

Measures AP’s in retina and function

Question 7

What does EOG

Answer 7

Measures function of retinal pigment epithelium and photoreceptors

Question 8

What does VEP do

Answer 8

Records optic nerve function

Question 9

When is it useful

Answer 9

MS

Question 10

What does reduced amplitude suggest

Answer 10

Ischaemia

Neuropathy

Question 11

What does latency suggest

Answer 11

Optic neuritis

Question 12

How do you investigate retinal pathology

Answer 12

Visual acuity / field
Fundoscopy
Fluorescein angiography
Optic coherence tomography 
Electrophysiology - EOG / ERG

Question 13

What is myopia

Answer 13

Short sightedness

Question 14

How does this occur

Answer 14

Light focuses in front of retina in VH as eye is too long

Question 15

What do you want to stop this happening

Answer 15

Bend rays of light less so focus on retina (use concave lens)
No accommodation

Question 16

What are the symptoms of short sightedness

Answer 16

Close objects are clear but distant = hazy
May have headache
Divergent squint

Question 17

How do you Rx

Answer 17

Biconcave lenses (minus lens)
Glasses
Laser eye surgery

Question 18

What should you do if presents with divergent squint

Answer 18

Test for refractive error

Question 19

What is long sightedness

Answer 19

Hypermetropia

Question 20

What happens

Answer 20

Light focuses past retina as eye is too short
Distant objects will focus past but can accommodate
Can focus on far away objects as accommodate but as move closes the power is used up

Question 21

Symptoms

Answer 21

Close up = hazy
Eye strain
Convergent squint

Question 22

How do you Rx

Answer 22

Biconvex lens

Laser eye

Question 23

What does convergent squint require

Answer 23

Immediate treatment to preserve vision and prevent a lazy eye

Question 24

Wha is astigmatism

Answer 24

Non spherical curvature of cornea or lens so everything is hazy

Question 25

How do you treat

Answer 25

Special glasses | Laser eye surgery

Question 26

What is presbyopia

Answer 26

Long sightedness of old age as lens less mobile so can't change shape

Question 27

How do you treat

Answer 27

Biconvex glasses

Question 28

What are causes of squint (strabismus) and what happens

Answer 28

Concomitant - imbalance of extra-ocular muscles = most common and occur in childhood Paralytic = rare Leads to diplopia Brain copes by reducing signal from less dominant eye leading to a lazy eye

Question 29

How do you Dx

Answer 29

``` Examination Refer ophthalmology Eye movement Fundoscopy to rule out retinoblastoma Visual acuity Corneal light reflexion test Cover test ```

Question 30

How do you Rx

Answer 30

Eye patches over good eye to prevent ambylopia and encourage use of the squint eye Refer 2 for surgery

Question 31

What are risk of surgery

Answer 31

Diplopia Slipped muscle Over-correction

Question 32

What are underlying issues

Answer 32

``` Usually idiopathic Cerebral palsy SOL - retinoblastoma Hydrocephalus Trauma ```