Approach to Visual Loss Flashcards
What does initial stabilisation involve?
Is there a life-threatening problem concurrent to visual loss?
Does the visual loss suggest a broader life/function threatening problem?
What are the important points in a visual loss history?
HOPC Unilateral/bilateral PHx Past ocular Hx FHx SHx Rx Allergies
What are the important points in a visual loss examination?
Visual acuity
Pupil reactions
Intraocular pressure
Which structures are most likely to be involved in visual loss?
Structures within visual axis
What is the most common cause of poor vision?
Refractive error
What are some neurological causes of ptsosis?
CN III palsy
Horner’s syndrome
What are some myogenic causes of ptosis?
Myaesthenia gravis
Myotonic dystrophy
What are some aponeurotic causes of ptosis?
Involutional
What are some mechanical causes of ptosis?
Orbital tumours
Oedema
Scarring
What is a cause of pseudoptosis?
Contralateral lid retraction
What mitochondrial disease can cause ptosis?
Chronic progressive external ophthalmoplegia
What should you think of when there’s transient blurring of vision, with or without epiphoria?
Tear film disruption
How can entropion blur vision?
Tear film disruption
Over time, what can entropion cause?
Corneal scarring
Pannus trichiasis
What is pannus trichiasis?
Misdirected growth of eyelashes towards cornea
What causes trachoma?
Chlamydia trachomatis
What are the complications of chronic trachoma?
Scarring of conjunctiva
Entropion
Blindness
What is the clinical presentation of Fuch’s endothelial dystrophy?
“My vision has been gradually getting blurry over months”
Corneal oedema
Descemet’s membrane folds
Same findings in contralateral eye
What is Fuch’s endothelial dystrophy?
Decompensation of corneal endothelial pump > corneal oedema
Usually bilateral
What is the treatment for Fuch’s endothelial dystrophy?
Topical 5% NaCl > dehydrates cornea
Corneal graft surgery
- Graft of endothelium only usually sufficient
What is the clinical presentation of keratoconus?
"My vision has been getting blurry again. I've had several new pairs of glasses this year, but it keeps getting worse" FHx Young age Visual acuity corrected with pin hole > not always, though PEARL Normal intraocular pressure Irregular curvature of cornea Munson's sign
What is Munson’s sign?
V shape in lower lid when looking down due to irregular shape of cornea
What is keratoconus?
Progressive thinning, weakness, and protrusion of cornea
Which layer of the cornea is primarily affected in keratoconus?
Stroma
What is the management of keratoconus?
Hard contact lenses
Cross-linking
Corneal transplant
What is the clinical presentation of acute angle closure glaucoma?
Few hours of painful unilateral red eye and worsening vision
Cloudy oedematous cornea
Mid-dilated pupil
Raised intraocular pressure
What is the emergency management for acute angle closure glaucoma?
Reduce intraocular pressure
Acetazolamide oral and IV STAT
Topical beta-blocker
Topical steroids
What is the clinical presentation of a cataract?
Gradual worsening of vision Glare Colours not as bright anymore Usually in older people Visual acuity not improved with pin hole PEARL Normal intraocular pressure Sclerosis of lens
What are the different types of cataract?
Cortical
Nuclear
Subcapsular
What are causes of cataracts?
Age-related Drugs - Steroids - Amiodarone Trauma, including intraocular surgery Systemic diseases - Diabetes - Myotonic dystrophy - Wilson's disease - Atopic dermatitis Ocular diseases - Uveitis - Myopia
What is the treatment for cataracts?
Lens removal and introcular lens insertion
What is the pathophysiology of a dislocation of the lens?
Zonular pathology
What is lens dislocation associated with?
Connective tissue disorders, including Marfan syndrome
What is the clinical presentation of vitreous haemorrhage?
“I lost vision in one eye today. It was like a curtain came down over my vision”
Affected eye VA: 6/60
PEARL
Nil RAPD
What are some important causes of vitreous haemorrhage?
Retinal detachment
Proliferative diabetic retinopathy
Trauma
What is the management for vitreous haemorrhage?
Often resolves slowly over weeks/months
Can need vitrectomy to clear blood
Risk of re-bleed
What is the clinical presentation of retinal detachment?
Flashes of light in one eye = traction of retina Floaters in one eye RAPD with extensive retinal detachment Retinal detachment with fundoscopy - Difficult to see in peripheries - Need to dilate pupil
What is the management for retinal detachment?
Urgent ophthalmological review
Surgical repair
What is a Weiss ring a sign of?
Posterior vitreous detachment
What is the clinical presentation of a central retinal artery occlusion?
Sudden, painless, unilateral loss of vision RAPD Pale retina Arteriolar attenuation Cerry red spot
How quickly does irreversible ischaemic damage to the retina occur?
After 90 min
What are the common causes of central retinal artery occlusion?
Atherosclerosis
Emboli
Haematological disorders
Inflammatory; eg: giant cell arteritis
What is the emergency management of central retinal artery occlusion?
Urgent priority to rule out GCA - ESR - CRP Lie patient flat Ocular massage Decrease introcular pressure > acetazolamide 500 mg IV STAT
What is the clinical presentation of central retinal vein occlusion?
Sudden, painless, unilateral loss of vision RAPD Retinal haemorrhages Macular oedema Cotton wool spots
What atherosclerotic associations are there with central retinal vein occlusion?
HTN
Diabtes
Hyperlipidaemia
Smoking
What inflammatory diseases are associated with central retinal vein occlusion?
Sarcoidosis
Behcet’s disease
SLE
Polyarteritis nodosa
What blood dyscrasias are associated with central retinal vein occlusion?
Protein C and S deficiency
Antithrombin deficiency
Antiphospholipid syndrome
Multiple myeloma
What ophthalmic conditions are associated with central retinal vein occlusion?
Glaucoma
Orbital mass
How does central retinal vein occlusion cause rubeosis iridis?
Blood vessels grow into iris
What is the treatment for central retinal vein occlusion?
Lifestyle changes
Intraocular pressure control
Intravitreal steroids
Anti-VEGF agents
What is the clinical presentation of a macular hole?
“I can’t focus on anything with one eye. When I try and look at something, it disappears”
Visual fields by confontration normal
What is the management for a macular hole?
Vitrectomy
Removal of macular traction
Insertion of gas
What is the clinical presentation of dry age-related macular degeneration?
Gradual decrease in central vision Central scotoma FHx of macular degeneration Drusen Geographic atrophy = coalesced drusen
What is the pathophysiology of dry age-related macular degeneration?
Loss of retinal pigment epithelium/photoreceptors
Associated with
- Increasing age
- Smoking
What is the management for dry age-related macular degeneration?
Predominantly supportive care Smoking cessation Vitamin supplementation > thought to reduce oxidative stress in retina - Vitamin C and E - Zinc - Copper
What is the clinical presentation of wet age-related macular degeneration?
Rapid decrease in central vision - weeks-months Metamorphopsia Central scotoma Drusen Geographic atrophy Lipid exudate Intra-retinal haemorrhage
What is the pathophysiology of wet age-related macular degeneration?
Choroidal neovascularisation = growth of abnormal leaky vessels in RPE
What is the management of wet age-related macular degeneration?
Investigate with fluorescein angiography and optical coherence tomography
Anti-VEGF intra-vitreal injections
What is the biggest risk factor for diabetic retinopathy?
Duration of diabetes
What are other risk factors for diabetic retinopathy?
Poor glycaemic control Poorly controlled HTN Hypercholesterolaemia Nephropathy Pregnancy Obesity
What is the most common cause of visual impairment in diabetic retinopathy?
Diabetic macular oedema
What are some features of diabetic retinopathy on fundoscopy?
Circinate ring Lipid (hard) exudates Intra-retinal haemorrhage Micro-aneurysms Venous beading Intra-retinal vascular abnormalities Neovascularisation of disc Neovascularisation everywhere Vitreous haemorrhage
What is the epidemiology of retinitis pigmentosa?
Most common retinal dystrophy
Sporadic/inherited
Affects rods first
Usually in young adults
What is the clinical presentation of retinitis pigmentosa?
"I'm concerned about my vision. I've nearly been in a few car accident. My night vision is so bad, that I've stopped driving in the dark altogether. Blindness tends to run in my family" Normal visual acuity PEARL Nil RAPD Intraocular pressure normal Annular scotoma Waxy pallor of disc Bone-spiculae retinal pigmentation Retinal arteriolar attenuation
What does posterior uveitis include?
Retinal vasculitis
Retinitis
Choroiditis
What are some causes of posterior uveitis?
Systemic inflammatory disorders - Behcet's disease - Sarcoidosis Viruses Fungal Protozoa Bacterial Lymphoma
What is the management of posterior uveitis?
Investigate cause Assess risk of bilateral vision loss Antimicrobials if infective cause Topical steroids Intraocular antimicrobials and steroids Systemic therapies
What is the clinical presentation of idiopathic (benign) intracranial hypertension?
Overweight, female, 20s
Headaches
Blurry vision
Bilateral swollen optic discs = papilloedema
What are the investigations for idiopathic intracranial hypertension?
Urgent neuroimaging
Lumbar puncture if cause not clear
What is the treatment for idiopathic intracranial hypertension?
Weight loss Medical Rx - Acetazolamide - Other diuretics - Corticostreoids Surgical Rx - Optic nerve sheath fenestration - Lumbar-peritoneal shut
What is the clinical presentation of optic neuritis?
“I woke up this morning and have very poor vision in one eye”
RAPD in affected eye
Normal intraocular pressure
Reduced colour saturation in affected eye
Blurred optic disc margin
Swollen, inflamed, disc = papillitis
What is the management for optic neuritis?
MRI brain and referral to neurologist to investigate for multiple sclerosis
High dose prednisolone
What are the causes of bilateral disc swelling?
Generally papilloedema
Malignant HTN
Pseudopapilloedema
What are causes of raised intracranial pressure due to mass effect?
Haemorrhage
Haematoma
Tumours
What are the causes of raised intracranial pressure due to increased CSF production?
Choroid plexus tumour
What are the causes of raised intracranial pressure due to reduced CSF absorption?
Venous sinus thrombosis
Aqueduct/foramen stenosis
Idiopathic intracranial hypertension
What are the causes of unilateral disc swelling?
Arteritic anterior ischaemic optic neuropathy
Non-arteritic anterior ischaemic optic neuropathy
Optic neuritis
Tumours
Infections
What are the causes of unilateral disc swelling reated to raised intracranial pressure?
Foster-Kennedy syndrome
Raised ICP where 1 optic disc already atrophic
What are the causes of pseudopapilloedema?
Optic disc drusen
Hypermetropia = shorter eye axial length > gives disc swollen appearaance
Tilted discs
What are the clinical features of giant cell arteritis?
Headache
Scalp tenderness
Jaw claudication
Associated polymyalgia rheumatica
Acute unilateral loss of vision
- Usually due to ischaemic optic neuropathy
- Can be due to central retinal artery occlusion
What are the investigations for giant cell arteritis?
ESR - classically >100
CRP
Temporal artery biopsy
What is the treatment for giant cell arteritis?
40-60 mg prednisolone (high dose)
What is primary open angle glaucoma?
Chronic degenerative condition affecting optic nerve
What is the progression of visual field loss in glaucoma?
Normal fields with blind spot >
Arcuate scotoma - usually not noticed by patient >
Progression of centrally sparing field loss - patient can still be unaware >
Snuff out - can present as acute vision loss
What are the signs of primary open angle glaucoma?
Increased optic cup-to-disc ratio
Progressive visual field loss
What are the risk factors for primary open angle glaucoma?
Positive FHx
High myopia
Diabetes
Elevated intraocular pressure
What are the most common causes of vision loss?
Refractive error Cataracct Diabetic retinopathy Macular degeneration Ocular surface disease
