24. Visual disturbance/impairment Flashcards
differentials for sudden vision loss
ischaemic/vascular
- retinal vein occlusion
- retinal artery occlusion: TIA/stroke/giant cell arteritis
- anterior ischaemic optic neuropathy: TIA/stroke/giant cell arteritis
- vitreous haemorrhage
- retinal detachment
- acute angle closure glaucoma
- optic neuritis
differential for gradual vision loss?
Refractive error
Cataracts
Macular degeneration
Chronic (open angle) glaucoma
Diabetic retinopathy
Hypertensice retinopathy
differentials for diplopia
eye muscle problem:
- myasthenia gravis
- graves
- strabismus
neurological:
- head injury
- stroke
- migraine
- tumour
- wernikes
Nerve problem (eg 3rd CN, 4th CN or 6th CN)
- diabetes
- congenital
- raised ICP
- MS
- guilian barre
examination vision loss
Inspection: is it RED (acute angle closure)
Optic nerve: acuity, visual fields, attention, accommodation, pupils, colour vision
- Pupil unreactive/not responding/ well to light/RAPD suggests optic nerve dysfunction therefore could be due to anterior optic neuropathy (GCA or TIA), optic neuritis etc
Eye movements: H test, any double vision? any pain on movement? (any CN palsys?)
To complete…
Opthalmoscopy
HbA1c, BP
Referral for slit lamp examination
what should you be able to label on fundoscopy
optic disc
optic cup
macula
fovea
retinal vein
retinal artery (thinner than veins)
history taking vision loss/disturbance
PC: onset? sudden? is the vision loss in one portion of your vision? eg the sides or the middle etc. floaters/flashes?
HoPC: PAIN?? - suggests acute angle closure glaucoma. pain on eye movement? (optic neuritis), do colours look the same? (loss of red in optic neurtis)
Associated symptoms: headache especially near temples?(GCA) weakness?
SHx:
eye trauma e.g. boxing, ask about occupation and hobbies
what is amaurosis fugax? causes
Amaurosis fugax describes a temporary loss of vision caused by a temporary interruption to the blood supply - like a curtain coming down…
causes of amaurosis fugax?
ischaemic/vascualr causes of sudden vision loss eg
Retinal vein occlusion
Retinal artery occlusion: TIA/stroke/GCA
Anterior ischaemic optic neuropathy: TIA/stroke/GCA
Giant-cell arteritis
As this may represent a TIA, 300mg aspirin is given
central retinal vein occlusion
presentation
causes
examination
fundoscopy
management
presentation: sudden, painless, reduction or loss in visual acuity, unilateral
causes:
Risk factors
increasing age
hypertension
cardiovascular disease
glaucoma
polycythaemia
examination: reduced visual acuity
fundoscopy:
“stormy sunset” multiple haemorrhages
management:
majority conservative
if macualr oedema, consider VGEF
central retinal artery occlusion
presentation
examination
fundoscopy
management
presentation:
sudden, painless, unilateral vision loss
examiantion: RAPD
causes:
TIA/stroke/GCA
fundoscopy
‘cherry red’ spot on a pale retina
management:
think of it as TIA/stroke/GCA
–> any underlying conditions should be identified and treated (e.g. intravenous steroids for temporal arteritis)
Anterior ischaemic optic neuropathy
presentation
causes
examination
fundoscopy
management
presentation: loss of vision
causes: TIA/stroke/GCA
examination: RAPD
fundoscopy: swollen pale disc and blurred margins
management:
think of it as TIA/stroke/GCA
–> any underlying conditions should be identified and treated (e.g. intravenous steroids for temporal arteritis)
vessel occluded in AION
posterior ciliary artery
cherry red spot
central retinal artery
blood supply optic nerve
central retinal artery
“stormy sunset” multiple haemorrhages
central retinal vein occlusion
Giant cell arteritis causing visual symptoms
presentation
examination
fundoscopy
management
PC: decreased visual acuity, temporal headache
examination: reduced visual acuity, tenderness over temple
fundoscopy: Retinal splinter haemorrhages or disc oedema. AION swollen pale disc and blurred margins.
management:
medical emergency due to risk of
- stroke
- blindness (a strple affecting the retinal vessels, optic nerve) - 90% AION (Anterior Ischemic Optic Neuropathy)
phone rheum on-call
Should have confirmatory test: USS halo sign or temporal artery biopsy
Initial
1. High dose oral glucocorticoids eg oral methylprednisolone
With visual loss:
1. IV methylprednisolone
+ Urgent ophthalmology review
+ Bone protection for steroids
refractory/relapsing : tocilizumab
vitreous haemorrhage
presentation
causes
examination
fundoscopy
management
presentation: painless vision loss, dark spots obscuring vision with a red hue
causes:
- DIABETES, bleeding disorders, anticoagulants
examination: decreased visual acuity, visual field defect if severe haemorrhage
dilated fundoscopy: may show haemorrhage in the vitreous cavity
if new onset rf urgently (<24hrs) for slit-lamp examination,
other stuff may be used eg:
ultrasound: useful to rule out retinal tear/detachment and if haemorrhage obscures the retina
fluorescein angiography: to identify neovascularization
orbital CT: used if open globe injury
retinal detachment
presentation
causes
examination
fundoscopy
management
PC: vision loss, curtain or shaddow progressing to the centre from the periphery, floaters or flashes,
risk factors
diabetes mellitus
myopia
age
previous surgery for cataracts
eye trauma e.g. boxing
examination
fundoscopy
the red reflex is lost and retinal folds may appear as pale, opaque or wrinkled forms
if the break is small, however, it may appear normal.
It is a reversible cause of visual loss, provided it is recognised and treated before the macula is affected.
rf urgently
plan pt with new onset flashes and floaters
Arrange immediate referral to an ophthalmologist with retinal surgery expertise to be seen on the same day, if there are signs of sight-threatening disease, such as:
- Visual field loss or changes in visual acuity.
- Fundoscopic signs of retinal detachment or vitreous haemorrhage.
any patients with new onset flashes and floaters WITHOUT VISUAL/FUNDOSCOPY CHANGES should be referred urgently (<24 hours) to an ophthalmologist for assessment with a slit lamp and indirect ophthalmoscopy for:
pigment cells
vitreous haemorrhage
posterior vitreous detachment
presentation
causes
examination
fundoscopy
management
presentation: no vision loss, floaters, flashes, blurred vision, cobwebs
causes:
ageing
myopia
fundoscopy: weiss ring
Investigations:
All patients with suspected vitreous detachment should be examined by an ophthalmologist within 24hours to rule out retinal tears or detachment.
Management:
Posterior vitreous detachment alone does not cause any permanent loss of vision. Symptoms gradually improve over a period of around 6 months and therefore no treatment is necessary.
If there is an associated retinal tear or detachment the patient will require surgery to fix this.
optic neuritis
presentation
causes
examination
fundoscopy
management
PC: unilateral decrease in visual acuity over hours or days
poor discrimination of colours, ‘red desaturation’
pain worse on eye movement
central scotoma
causes:
multiple sclerosis: the commonest associated disease
diabetes
syphilis
examiantion: relative afferent pupillary defect
Mangement
MRI of the brain and orbits with gadolinium contrast is diagnostic in most cases
high-dose steroids
recovery usually takes 4-6 weeks
most common cause of blindness in the UK
Age-related macular degeneration
what is age related macualr degenertaion
Degeneration of the central retina (macula) is the key feature with changes usually bilateral.
ARMD is characterised by degeneration of retinal photoreceptors that results in the formation of drusen which can be seen on fundoscopy and retinal photography. It is more common with advancing age and is more common in females.
fundoscopy how is wet AMD different to dry? pathophysiology
In wet AMD, new vessels develop from the choroid layer and grow into the retina (neovascularisation). These vessels can leak fluid or blood, causing oedema and faster vision loss. A key chemical that stimulates the development of new vessels is vascular endothelial growth factor (VEGF). This is the target of medications to treat wet AMD.
which is more common wet or dry AMD?
dry = 90%
risk factors macualr degeneration
Older age
Smoking
Family history
Cardiovascular disease (e.g., hypertension)
Obesity
Poor diet (low in vitamins and high in fat)
dry and wet AMD
compare presentation
Presentation:
both:
- vision loss- reduction in visual acuity particualrly for close objects
- difficulties in dark adaptation
- fluctuations in visual disturbance
- visual hallucinations may also occur resulting in Charles-Bonnet syndrome
- photopsia, (a perception of flickering or flashing lights), and glare around objects
gradual in dry ARMD
subacute in wet ARMD
Wet AMD presents more acutely than dry AMD. Vision loss can develop within days and progress to complete vision loss within 2-3 years. It often progresses to bilateral disease.
differentiating AMD and glaucoma presentation
Glaucoma is associated with peripheral vision loss and halos around lights. AMD is associated with central vision loss and a wavy appearance to straight lines. This helps you tell them apart in exams
examination and fundoscopy ARMD
Reduced visual acuity using a Snellen chart
Scotoma (an enlarged central area of vision loss)
Amsler grid test can be used to assess for the distortion of straight lines seen in AMD
Drusen may be seen during fundoscopy
what invetsigation is useful for wet
ARMD
Fluorescein angiography involves giving a fluorescein contrast and photographing the retina to assess the blood supply, showing oedema and neovascularisation in wet AMD.
management wet ARMD
Anti-VEGF medications
laser photocoagulation but is more risky
management dry ARMD
Management involves monitoring and reducing the risk of progression by:
Avoiding smoking
Controlling blood pressure
Vitamin supplementation has some evidence in slowing progression
what are cataracts
A cataract is a common eye condition where the lens of the eye gradually opacifies i.e. becomes cloudy. This cloudiness makes it more difficult for light to reach the back of the eye (retina), thus causing reduced/blurred vision
causes of cataracts
Normal ageing process: most common cause
Other possible causes
Smoking
Increased alcohol consumption
Trauma
Diabetes mellitus
Long-term corticosteroids
Radiation exposure
Myotonic dystrophy
Metabolic disorders: HYPOCALCAEMIA
presentation cataracts
Reduced vision
Faded colour vision: making it more difficult to distinguish different colours
Glare: lights appear brighter than usual
Halos around lights
o/e cataracts
A Defect in the red reflex: the red reflex is essentially the reddish-orange reflection seen through an ophthalmoscope when a light is shone on the retina. Cataracts will prevent light from getting to the retina, hence you see a defect in the red reflex.
invetsigations catracts
Ophthalmoscopy: done after pupil dilation. Findings: normal fundus and optic nerve
Slit-lamp examination. Findings: visible cataract
