posterior eye conditions Flashcards
sudden VF loss investigations
- Tailored History
- Slit Lamp Assessment – excludes anterior causes, indicative of pathology in posterior structures
- Visual Acuity, if no glasses or if there are media opacities use pinhole to see if actual visual loss
- Visual Fields – better idea of abnormality location (monocular pre chiasmal – affecting retina or optic nerve), binocular chiasmal or post chiasmal
- Pupils – RAPD (indicates an intraocular symmetry in visual input, so caused by abnormality which effects the optic nerve or RNFL, wouldn’t get RAPD in post chaismal defect as this would not result in asymmetrical visual input between the 2 eyes – would effect both eyes
- Eye movements –if pain possibly optic neuritis
- Dilated Fundoscopy (also OCT and fundus photos)
signs and symptoms of CRAO
Symptoms
* Sudden painless monocular loss in vision
Signs
* Profound RAPD present (can have amaurotic pupil – completely unresponsive)
* Emboli? ( could see, the primary cause, look for yellow plaque, could be at disc of CRAO, or if BRAO then at effected area)
* Whitish, oedematous retina (depends how long it has been)
* Cherry red spot (if established)
* Disc pallor
Retinal vasculature narrowing (arteriola attenuation) (in early and acute stages)
Check if px had/has stroke/ TIA – ask about signs.
Arterial fibrillation then greater risk of developing emboli
BRAO signs and symptoms
Symptoms
* Sudden painless monocular drop in vision…. However vision is often unaffected, depends which branch affected
Signs
* RAPD often present (depends on severity)
* Emboli at bifurnication points
* Whitish, oedematous sector of retina
* Retinal vasculature narrowing in area supplied by the affected branch
* Altitudinal or sectoral visual field defect
management by optom for CRAO and BRAO
- College CMG - CRAO if less than 12 hours old same day referral to ophthalmology. Greater Glasgow - CRAO if less than 24 hours old same day referral to ophthalmology
- Initiate Ocular Massage whilst patient lies supine in new cases
- BRAO can also benefit from ocular massage
- Ocular Massage dilates the ophthalmic and retinal arteries, can cause a thrombus to disintegrate and may cause an impacted emboli to move to a more peripheral part of retinal circulation, and reduces the IOP
- CRVO if elevated IOPS refer within a week, if IOPS over 40 refer same day
- Patients will be referred by ophthalmology for a stroke work up (greater risk of stroke if emboli from carotid artery)
Retinal vein occlusion RVO
- Thrombus in the CRV or a branch of the CRV
- Atheriosclerotic aetiology
- Common associations - hypertension, older age, hyperlipidaemia, diabetes, glaucoma, contraceptive pill, smoking
- Can result in neovascular glaucoma, happens faster in CRAO than CRVO (less common in branch)
signs RVO
- Variable presentation – depends where, if beginning of vein then more visual loss– blurred vision, metamorphopsia, visual loss
- Could have no/minimal symptoms (if thrombus has lodged not centrally)
- Poorer prognosis if vision poor and greater risk of neovascular
- Dilation and tortuosity of retinal veins
- Blot and flame haemorrhage
- Cotton wool spots and retina oedema
- CMO (cystoid macular oedema) !! important to check depends management
- Retinal whitening
- Disc oedema
- RAPD only in ischaemic CRVO
management RVO
- Branch more common than central
- Not as worried about stroke than CRAO
- Optometric Management
- BRVO 5-6 x more common than CRVO
- Referral urgency depends on presentation
- If CMO present secondary to BRVO/CRVO then intravitreal anti-vegf will generally be given so referral urgency is usually within 1-2 weeks
- Depends on guidelines
Eg Lothian guidelines Any Branch retinal vein occlusion (BRVO) with a reduction in vision (i.e. cystoid macular oedema present) should be referred to PAEP ARC clinic for review in 1-2 weeks and possible listing for treatment with intra-vitreal anti-VEGF (lucentis)
Any BRVO with no reduction in vision (i.e. no CMO) should be referred routinely to PAEP outpatients and should be advised to attend their GP within 1-2 weeks for BP check and routine blood tests.
Routine investigations include: FBC, Electrolytes, Cholesterol/Lipids, Glucose and LFTs.
Amaurosis Fugax management
Patients should be referred urgently to a TIA clinic for review within 48hrs if they present with the following symptoms:
* Amaurosis Fugax of sudden onset within 2 weeks, with no headache or associated pain and no ocular pathology/abnormality present, need seen in 48 hours
* Sudden onset previously undiagnosed visual field total scotoma of less than 2 weeks with no ocular pathology (i.e. homonymous hemianopia or quadrantopia)
To refer to a TIA clinic there is a direct phone number available 24 hours a day 7 days a week
retinal detachment differential diagnosis
Posterior Vitreous Detachment
Retinoschisis
Choroidal Mass
what to do when shaffers sign seen but no break or tear found
Shaffers Sign (pigmented particles in anterior vitreous) = retinal detachment , referral even if break/tear not found
what is retinoschsis
no symptoms, common in hyperopia, benign splitting of neurosensory retina at the level of the outer plexiform layer - OCT can be handy here – helps differentiate where retina detached ( if whole retina then retinal detachment)
no retinal break, idiopathic
inferior temporal peripheral area common, bilateral common
in 5% of the population – underdiagnosed
features or retinoschsis
no shaffers sign
dome shaped elevation
Leads to loss of visual function in this area but as peripheral rarely noticed
retinoschsis vs retinal detachment
haemorrhage or pigment in RD and not in retinoschisis
shifting fluid in RD and not in retinoschisis - ask px to move eye
retinoschisis has domed shaped and smooth and has absolute scotoma
retinoschisis mangement
not an emergency, usually not progressive, observe px and make sure doesn’t change overtime
emergency referral for what
- retinal detachment
- pigment in the anterior vitreous (tobacco dust)
- vitreous, retinal or pre-retinal haemorrhage, or
- lattice degeneration or retinal break, with symptoms.
