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Flashcards in Assessment of Visual Failure - Murtag Deck (30):
1

Blindness by WHO

less than 3/60

2

Minimum vision for driving in Australia

6/12

3

Key points for Sudden vision failure

Transient occlusion of retinal artery (amaurosis) and migraine

4

Flashing lights

retinal detachment

5

Floaters and blobs

Aging
Pigment in viterous humor
Vitreous hemorrhage
Posteroir viterous detachment
Choroiditis

6

Acute onset of floaters

posterior vitreous detachment

7

Causes of central vision impairment

defective retinal
- Refractive error
- opacity in occular media
- macular/optic nerve dysfunction

8

Causes of peripheral vision impairment

extramacular disease
defects in visual pathway

9

Oculotoxic drugs

TB
ethambutol
quinine, chloroquinine

10

Family History important in vision loss

DM
Migraines
Lebers heriditary optic atrophy
Tay-Sach disease
Retinitis pigmentosa

11

Causes of coloured halos around lights

Glaucoma
Cataracts

12

Causes of worsening vision in night or around dim lights

retinitis pigmentosa
hysteria
syphilitic retinitis

13

Causes of headache with vision changes

Migraine
Temporal arteritis
Benign intracranial HT

14

Causes of central scotomata (blind spot)

Macular Disease
Optic Neuritis

15

Pain on occular movement

Retrobulbar neuritis

16

Distortion Micropsia (smaller), macrospsia (larger)

Macular degeneration

17

Disorders to exclude

1. DM
2. Gaint cell (temporal) arteritis
3. hypopiturism (pituatary adenoma)
4. Cerebrovascular ischemia/carotid artery stenosis
5. MS
6. Cardiac disease (arrhythmias and SBE - emboli
7. Anemia (severe can cause retinal hemorrhages and exudate)
8. Marfan's syndrome - subluxated lens
9. Melanoma of choroid

18

Examinations of vision failiure

1. Visual Acuity - Snellen Chart, pinhole testing ?refractive
2. Pupil reaction - afferent (sensory) responses to light ?temporal arteritis, ?central retinal artery occlusion, ?optic neuritis
3. Confrontation field
4. Colour vision
5. Amslers grid
6. Fundus exam with dilated pupil - note red reflex (?cataracts, malignant melanoma), retina, macula, nerves
7. Tonometry ?glaucoma

19

Investigation

1. Blood test - Full blood (?Anemia, ?lead poisoning ?leukemia)
- ESR - ?Temporal cell arteritis
- Blood sugar ?DM
2. Temporal artery biopsy ?temporal cell arteritis
3. CT/MRI ?CVA, ?optic nerve lesion, ?space occuping lesions
4. Formal perimetry and Bjerrum screen ?glaucoma
5. Fluroscein angiography ?retinal vascular obstruction, ?DM retinopathy
6. Visual evoked potential ?demyelinating disorders
7. Carotid doppler US

20

Types of Macular degeration

Dry - build up of drusen in retinal pigment epithelium leading to loss of retinal pigment epithelium
Wet - choroidal neovascularisation

21

Urgent consideration for vision loss

1. Acute angle closure glaucoma - severe periorbital pain, with abdo symptoms
2. Retinal detachment - visual field loss, peripheral vision loss, flashes and floaters, surgery immediately
3. Retinal vascular occlusion - similar to detachment
4. Corneal ulcer - vision loss w/ painful red eye
5. Pituitary apoplexy - acute vision loss with headache and ocular motility disorder
6. Gaint cell artheritis - monoocular, jaw caudication and headache, scalp tenderness, weight loss
7. Cerebrovascular accident
8. Uveitis - conjuctivitis
9. Post-operative endophthalmitis - painful red eye after cataract surgery
10. Trauma

22

Sudden monoocular vision loss in older patients

Gaint cell arteritis

23

Sudden monoccular vision loss in younger adults

Embolic event - from coagulation disorders

24

DM patient with recent hyperglycemic event and now vision loss

refractory error due to lens swelling

25

Drugs causing colour changes to vision

digoxin = yellow
erectile dysfunction drug = blue

26

Corneal Ulcer

- Think for contact lens wearers
- Painful red eye with watery or mucoid disarge
- Exam = Fluorescien staining,
First test = gram stain for bacteria, corneal culture

27

Dry eye syndrome

-Intermittent visual blurring, may be worse in morning or evening, gritty sensation, light sensitivity without photophobia. relieved by artificial tear use.
Exam = normal, slit lamp may show occular surface irregularity
1st test = tear breakup time

28

Dry age related macular degeration

acute or chronic painless loss of vision or distortion of the central vision.
Exam = distorted central acuity with normal peripheral vision
1st test = fluorescein angiogram
refer to retinal specialist within 72 hours

29

Posterior Uveitis

painful onset of clouding, slowly, flashes and floaters, photophobia, pain on eye movement
Exam- tender red eye, +/- nodular lesion on sclera, cloudy/obstructed view of retina
1st test = FBC with differentials (inflammatory vs infective)

30

Cataracts

painless, progressive loss of vision