Differential diagnosis of blurred vision Flashcards
Acute conditions causing blurred, painful red eye:
Corneal ulcer
Uveitis
AACG
Acute conditions causing blurred, painless white eye:
CRAO CRVO Age related macula degeneration (wet) AIOP/non-AIOP Retinal detachment
Chronic conditions causing blurred vision:
Diabetic retinopathy Diabetic maculopathy Glaucoma Cataract Age related macula degeneration (dry)
Important risk factor for corneal ulcer:
Contact with the cornea e.g. contact lens/trauma/FB
Symptoms of corneal ulcer:
Unilateral acute pain Red eye FB sensation Decreased VA Photophobia Watering
Management of corneal ulcer:
Corneal scrapings for cultures and g stain
Hourly topical abx: ofloxacin
Signs of corneal ulcer:
White corneal infiltrate Diffuse conjunctival injection Mucopurulent discharge Hypopyon Anterior chamber cells (slit-lamp) Progressive ulceration
Complications of corneal ulcer if untreated:
Corneal perforation
Endopthalmitis
Signs of anterior uveitis:
Circum-corneal injection Keratic precipitates Watery discharge Possible constricted/distorted pupil Hypopyon (present in AI conditions and infections like herpes zoster)
Symptoms of anterior uveitis:
Uni/bilateral red painful eye Normal to mildly reduced VA Photophobia Tearing Attack is several days to 6 weeks
Complications of anterior uveitis:
Posterior syenchiae
Secondary glaucoma
Secondary cataract
Treatment of anterior uveitis:
Topical steroids and cycloplegia
Symptoms of AACG:
Unilateral loss of vision (6/36 or worse)
Halos
Red and painful eye
N+V
Signs of AACG:
Reduced VA Corneal oedema Raised IOP Oval unreactive pupil Hypermetropia Previous intermittent symptoms
Signs of age-related macula degeneration (wet):
Grey/green lesion consisting of new blood vessels (choroidal neovascularisation)
Yellow exudates
Retinal haemorrhage
Treatment of age-related macula degeneration (wet):
Regular intravitreal injections of anti-VEGF
Lifestyle advice + smoking cessation
Associations of diabetic retinopathy:
CN palsies III, IV and VI
pupil usually spared in diabetic CN III palsy
Signs of diabetic retinopathy:
Aneurysms
Dot and blot haemorrhages
Hard exudates (lipid) and cotton wool spots (soft exudate)
Retinal and macular oedema
Diplopia
New vessels in disc and retina and iris rubeosis
What causes sight loss in diabetic retinopathy?
Macular oedema Macular ischaemia Vitreous haemorrhage Tractional retinal detachment Cataract (do red reflex)
Treatment of diabetic retinopathy:
Focal macular laser to reduce macular oedema
PRP to treat new vessel formation
Intravitreal anti-VEGF injections (e.g. ranbizumab)
Vitrectomy
What is the purpose of a vitrectomy in diabetic retinopathy?
Remove vitreous haemorrhage
Relieve tractional retinal detachment
Presentation of glaucoma:
Disc cupping and nerve head damage
Loss of peripheral VF
Increased IOP (>21mmHg)
What is normal tension glaucoma?
Optic nerve cupping and VF loss despite normal IOP
Classic VF defect in glaucoma?
Arcuate scotoma - defect progressing from the disc, around the macula with preserved central vision
First line treatment in glaucoma:
Reduce aqueous humour production with beta blocker, carbonic anhydrase inhibitor or alpha agonist drops
Glaucoma treatment to increase aqueous outflow:
Prostaglandin analogues
Surgery in glaucoma:
Laser open trabecular meshwork/new route
Cataract causes which ammetropia?
Myopia
and glare
Key exams in cataract:
Decreased red reflex
Difficult view of fundus
Decreased VA
RFs for cataract:
Smoking, UV exposure, age Congenital/birth trauma/maternal rubella or toxoplasmosis Diabetes Trauma Corticosteroids Eye disorders e.g. uveitis
Different cataract presentations:
Nuclear (dark yellow, age)
Posterior sub-scapular
Cortical (spokes, water clefts/vacuoles)
Treatment of cataract:
Surgical removal of lens and insertion of an artificial intraocular lens
What is the leading cause of blindness in the western world?
Age-related macula degeneration (dry)
Characteristics of dry AMD?
Progressive atrophy of macula retinal pigment epithelium cells causing gradual loss of central vision and reduction in VA
Peripheral vision is retained
Signs of dry AMD:
Drusen - tiny yellow accumulations under near-retina from the photoreceptors
Mottled appearance of macula
Marked central atrophy (if advanced)
Investigations for dry AMD:
Dilated fundus exam
Investigation for wet AMD:
Fluorescein angiography
Prognosis for dry AMD:
Slow deterioration in vision as there is no treatment
May progress to wet
