Sudden Loss of Vision Flashcards
What are the most common causes of sudden painless loss of vision and what is it in elderly
Ischaemic optic neuropathy Vascular Vitreous haemorrhage Retinal detachment Retinal vein or artery occlusion GCA - usually pain
If elderly = vascular till proven otherwise
What do you do if someone presents with acute visual loss
Stay calm and reassure
Get a clear Hx
Treat Sx e.g. pain / nausea
Early referral to ophthalmology and urgent senior review
What does loss of vision tend to indicate
Problem in posterior part of eye
What are the 4 categories
Vascular / ischaemic problem
Vitreous problem
Retinal detachment
Macular problem
What are vitreous issues
Posterior vitreous detachment
Proliferative retinopathy
What are macular problems
Age related = gradual
Macular hole
Central serous retinopathy
What causes vascular / ischaemic issues
Atherosclerosis Embolism Dissection Vasculitis Hypo-perfusion Venous disease
What would cause unilateral loss
Problem in eye or optic nerve
Retinal vein or artery occlusion
Can be central or branch
Ischaemic optic neuropathy
What causes bilateral
After decussation of fibres at chasm
CVA / TIA
- Amourosis fujax
Retinal migraine
Is someone presents with visual loss what do you want to ask
General PMH / drug review Uni or bilateral When did you lose vision - Sudden - Gradual What is vision loss like - General blur - Particular part lost (suggest branch) - Whole field (central vein) - Any tunnel - Lke a curtain Is there anything else in vision? - Flashes? - Floaters? - Any distortion Any pain associated - Pain on eye movement - Photophobia - Headache Is the eye red Any trauma Is BP / DM well controlled Any thrombotic / haematological conditions./ use of OCP
What does curtain coming down suggest
Amourosis fujax
DM
Vitreous haemorrhage
What causes amaurosis fujax
Embolism in retinal artery
How do you Rx
Aspirin 300mg
Refer urgent to TIA clinic
What does CVA cause
Hemianopia
How does migraine present
Zig zag or blobs
Prior to headache forming
What causes ischaemic optic neuropathy
Occlusion of ciliary artery damaging optic nerve
What does it present with
Monocular visual loss
Afferent pupil defect
Pale disc on fundoscopy if long term
What causes central retinal vein occlusion
Age Hypertension Hyperviscosity e.g. polycythaemia Glaucoma - raised IOP Vasculitis - GCA
How does it present
Sudden painless loss of vision
Tends to be more over days to weeks
where as arterial = seconds - minutes
Pupil defect
How do you differentiate ischaemic from non-ischaemic causes of occlusion
Ischaemic
- Extensive
- Deep haemorrhage
- Relative afferent pupil defect
- Severe visual loss
What is seen in the retina on fundoscopy ???
Blood leaks everywhere + fluid build up as vein to take away = blocked Margarita pizza Swollen optic disc Blot haemorrhage 4+ Dilated vessel Cotton wool
What investigations do you do
Ophthalmology blood screen + referral - FBC, U+E, CRP, ESR, clotting + vasculitis screen Inflammatory markers to rule out GCA BP check FBC for hyperviscosity Blood sugar Lipids and cholesterol
How do you Rx
Refer opthamology within 2 weeks or urgent if young
Monitor for complications
Treat vascular RF
What are complications
90% chance of long term visual loss
Neovascularisation due to release of VEGF to create collateral
- May cause vitreous haemorrhage
Macular oedema
How do you Rx complications
Anti-VEGF
Laser photocoagulation to burn off vessels
Dexamethasone for oedema
What causes central retinal artery occlusion
Atherosclerosis Hypertension Emboli Inflammation - GCA Glaucoma
What is CRAO
A form of stroke
Ophthalmic emergency
Time critical as can cause permanent damage to retinal ganglion cell
What must you do
Look for cause
- DM
- Smoking
- Cholesterol
How does it present
Sudden painless loss of vision Seconds - minutes Afferent pupil defect Usually monocular Branch = certain part Retinal vein = whole field
What is seen on retina
Cherry red spot
Pale optic disc
Pale as no blood
May still have red arteries due t collateral
If chronic = complete pale as retinal cells dead
What do you do if suspect
Refer ophthalmology
Ophthalmic screen
- FBC, U+E, CRP, ESR, clotting + vasculitis
Want to know if on anti-coagulant as may affect management
How do you Rx
GCA = potential reversible
Ocular massage to lower pressure (10 seconds pressing if 5s interval)
- Aim to dislodge thrombus into a branch of artery)
Nitrates to dilate
Inhaled carbogen (CO2 + O2) removes AH and reduce pressure
Anterior chamber paracentesis
Infusion of tPA in artery
- Careful if on anti-coagulant
Intra-arterial fibrinolysis = new technique where put needle into eye
What is posterior vitreous detachment and what is role of vitreous
Separation of vitreous membrane from retina
VH
- Keep structure of eye
- Allow focusing of light onto retina / macula
What causes / what are the types
Rhegmatogenous
- Natural part of aging as fluid less viscous and does not hold shape / idiopathic
Non-Rhegmatogenous - Trauma e.g. surgery - Vasculitis - Hypertension - DM Scar tissue / new tissue grows on retina and pulls it away from layers underneath or fluid collect under
How does it present
Sudden floaters in eye
Flashes of light
Blurred vision
If have these Sx go to E.D as could be start of retinal detachment or could cause tear
What does it suggest if dark curtain descend or peripheral visual field just comes in and closes
Retinal detachment
What do you do if patient complains of symptoms suggestive
Opthmaologist within 24 hours to rule out retinal tear or detachment as will cause permanent loss of vision
How do you Dx and Rx
Symptoms improve over 6 months Ophthalmic blood screen Intra-ocular USS / CT / MRI - RULE out tear/ detachment Slit lamp - Look at back of eye to see impact on optic nerve
Rx
- Urgent cryotherapy photo-coagulation
- Vitre-retinal surgery if associated tear or go onto detach
85% chance of recovery if treated
What does posterior vitreous detachment rarely cause
Retinal tear and detachment
Vitreous haemorrhage
What causes retinal detachment
Fluid entering space between 9th and 10th layer
- Blunt trauma causing tear and VH to enter
- Liquified VH (part of ageing process - vitreous detachment causing tear)
How does retinal detachment present
Features of vitreous detachment - Flashes / floaters Dense shadow that peripherally progresses to centre Veil or curtain PERIPHERAL field defect Sight threatening
What are RF
Age FH Myopia Trauma Cataract surgery Posterior vitreous detachment DM retinopathy
When do you have major concern
Myopia - short sighted
Recent trauma / surgery
More likely to detach
Loss of vision like a curtain
How do you Rx
Surgical repair within a few days
Emergency yas outer retina replies on choroid
Posture patient so fluid moves away from macula
When do you do emergency surgery
If macula attached to detachment
Can can delay in Dx lead too / complications
Macula and central vision loss
Vitreous haemorrhage
DOES not cause retinal haemorrhage
What causes retinal haemorrhage
Retinal vein occlusion
Diabetic retinopathy
What is vitreous haemorrhage
Bleeding into VH
What causes vitreous haemorrhage
Bleed from any disruption to retinal vessel
- DM proliferative retinopathy
- Retinal tear or detachment which has torn into vessel
- Posterior vitreous detachment
- Ocular detachment - shaken baby syndrome
If DM
Proliferative retinopathy til proven otherwise
If non-DM
Rental tear or detachment tip proven otherwise
What does vitreous haemorrhage cause
Painless loss of vision
Haze
Red hue
Floaters
What puts you at higher risk
DM Vitreous detachment Bleeding diosrder Anti-coagulant Severe myopia
How do you Dx
Dilated fundoscopy shows visible blood Slit lamp Orbital USS Floruscein angiography Orbital CT
What is issue with fundoscopy
May show haemorrhage
Can’t visualise retina due to haemorrhage
What does slit lamp show
RBC in vitreous
Why is orbital USS used
Used to rule out retinal tear or detachment
Why do you do flurscein angiography
Look for neovascularisation
How do you Rx
Conservative
If fresh should resolve in days to week
Sleep with raised posture to decrease BP
Surgical vitrectomy if significant bleed
- Remove all VHand replace
Laser photocoagulation once stable if less severe
Variable prognosis
What do floaters in vision suggest
Vitreous pathology
Vitreous detachment = most common
Vitreous haemorrhage = most common in DM
Uveitis
What must you exclude if floaters in vision
Retinal tear or detachment with ocular USS
What causes diffuse loss if >50
Central retinal vein or artery occlusion
Retinal detachment
Optic neuropathy
CVA
What causes diffuse loss <50
Optic neuropathy
Retinal detachment usually due to trauma
