Medicine - Ophthalmology Flashcards
Esotropia
Form of strabismus
1 eye deviates towards the nose
Strabismus
eye misalignment caused by imbalance in muscles holding the eye
Myopia
Near-sightedness
Light focuses in front of retina
Eye too long
Hyperopia/ Hypermetropia
Far-sightedness
Light focuses (theoretically) beyond retina
Eye too short
Presybopia
Age related loss of reading vision
Diminishing flexibility of lens
Emmetropia
No refractive error or visual defects
Amblyopia
“Lazy eye”
vision development disorder in which an eye fails to achieve normal visual acuity, even with prescription glasses or contact lenses
Metamorphopsia
Straight lines appear wavy
Astigmatism
Cornea or crystalline lens of the eye (or both) are not the ideal spherical ‘football’ shape, but more like the pointed end of a rugby ball.
Eye focuses light at 2 separate points on the retina, which blurs + distorts vision.
Where is the macula? What is it responsible for?
Central part of retina
Sharp, detailed vision
Depression/ pit = Fovea: greatest VA
Give differentials for sudden painless visual loss
Vitreous haemorrhage
Retinal detachment
Retinal migraine
Central retinal vein occlusion
Central retinal artery occlusion
Non-arteritic ischaemic optic neuropathy
Give differentials for painful visual loss
How can you tell which eye is being examined on fundoscopy pictures?
Optic disc usually on nasal side of patient
Give the 4 features of Horner’s syndrome
Miosis (constricted)
Ptosis
Enopthalmos (sunken eye/ narrow palpebral aperture)
Anhidrosis (loss of sweating 1 side)
What feature distinguishes congenital Horner’s syndrome from other causes?
Heterochromia: difference in iris colour
Which causes of Horner’s syndrome cause anhidrosis of the face, arm and trunk?
Central lesions
Stroke
Syringomyelia
MS
Tumour
Encephalitis
Which causes of Horner’s syndrome cause anhidrosis of the face?
Pre-ganglionic lesions
Pancoast’s Tumour
Thyroidectomy
Trauma
Cervical rib
Which causes of Horner’s syndrome DONT cause anhidrosis?
Post-ganglionic lesions
Carotid artery dissection
Carotid aneurysm
Cavernous sinus thrombosis
Cluster headache
Give signs and symptoms caused by Pancoast tumours
Ipsilateral invasion of sympathetic cervical plexus causes:
Horner’s syndrome
Shoulder + arm pain (brachial plexus invasion)
Hoarseness (pressing on recurrent laryngeal nerve)
3 features of an Adie pupil
Tonically dilated pupil
Slowly reactive to light with more definite accommodation response
Commonly seen in females accompanied by absent knee/ ankle jerks
What causes an Adie pupil?
Damage to parasympathetic innervation of eye due to viral/ bacterial infection
What is characteristic of a Marcus-Gunn pupil?
RAPD seen in swinging light test
Pupils constrict less + therefore appear to dilate when light is swung from unaffected to affected side
What are the most common causes of a Marcus-Gunn pupil?
Damage to optic nerve
Severe retinal disease
What is Hutchinson’s pupil?
Unilaterally dilated pupil, unresponsive to light
What does Hutchinson’s pupil result from?
Compression of occulomotor nerve of same side by intracranial mass e.g. tumour, haematoma
What are Argyll-Robertson pupils?
Bilaterally small irregular pupils that accommodate but don’t react to bright light
Give 2 causes of Argyll-Robertson pupils
Neurosyphilis
Diabetes mellitus
What mneumonic can be used to remember the features of Argyll-Robertson pupils?
Accommodation Reflex Present (ARP) but Pupillary Reflex Absent (PRA)
Recall the features of optic atrophy
Mnemonic: Optic Atrophy Can Reduce Sight
Optic disc pale
Acuity reduced
Colour vision reduced (especially red)
RAPD (relative afferent pupil defect)
Scomata centrally
What are the 2 most common causes of optic atrophy?
MS
Glaucoma
Recall 4 red flags when assessing red eyes
Photophobia
Poor vision
Fluorescein staining reveals foreign material
Abnormal pupil
Give 5 signs/ symptoms of corneal foreign body
Eye pain
FB sensation
Photophobia
Watering eye
Red eye
Give 6 indications for referral to ophthalmology with corneal FB
Penetrating eye injury due to high velocity/ sharp objects
Significant orbital/ peri-ocular trauma
Chemical injury (irrigate for 20-30 mins before referring)
FB composed of organic material e.g. soil, seeds (higher infection risk)
FB in or near centre of cornea
Any red flags e.g. severe pain, irregular, dilated or non reactive pupils, significant reduction in visual acuity
List 7 causes of blurred vision
Refractive error: most common
Cataracts
Retinal detachment
ARMD
AACG
Optic neuritis
Amaurosis fugax
What can be used to determine whether blurred vision is due to refractive error?
Pinhole occluder
If blurring improves with pinhole occluder then likely cause is a refractive error
Refer to optician
Is photophobia more likely to be present in acute glaucoma or anterior uveitis?
Anterior uveitis
What are the typical signs and symptoms of acute closed angle glaucoma?
Reduced acuity
N+V
Haloes around lights
Severe pain
What may be seen on examination in acute closed angle glaucoma?
Cloudy/ red cornea
Fixed + mid-dilated pupil
What are some risk factors for acute closed angle glaucoma?
Hypermetropia (key one)
Female
FH
Old age
What sort of examination can examine fluid drainage from the eye?
Gonioscopy with slit lamp
What are the general principles of management of acute closed angle glaucoma?
Refer
Medicate
Laser peripheral iridiotomy
Lens extraction
What drugs can be used to treat acute closed angle glaucoma?
IV:
Carobonic anhydrase inhibitor (reduces aqueous formation)
Top:
Carobonic anhydrase inhibitor
Beta blocker (also reduces aqueous formation)
Alpha-2 agonist (miosis opens blockage)
How does anterior uveitis usually present?
Acute pain
Photophobia
Reduced acuity
Hypopyon
How does the eye appear in anterior uveitis?
Irregular, small pupil
Hypopyon
What is episcleritis?
Inflammation below the conjuctiva in the episcleral layer
How does episcleritis usually present?
Asymptomatic
What is scleritis?
Full-thickness inflammation of sclera
usually non-infective cause
What conditions is scleritis associated with?
Rheumatoid arthritis (most commonly)
Systemic Lupus Erythematous
Granulomatosis polyangiitis
Sarcoidosis
Give 5 signs and symptoms of scleritis
Red eye
Painful + worse on eye movement
Watering
Photophobia
Gradual decrease in vision
What can be seen on examination in scleritis and how can it be differentiated from episcleritis?
Conjunctival oedema
Scleritis much more diffuse than episcleritis
If you add phenylephrine drops the sclera goes white in episcleritis but stays red in scleritis
Describe management of scleritis
Urgent referral + assessment by opthalmologist(\<24 h) NSAIDs PO Cortisosteroids PO for severe presentations Immunosuppressants for resistant cases
How can viral vs bacterial vs allergic conjunctivitis be differentiated by appearance?
Viral: waterey and unilateral
Bacterial: sticky and unilateral
Allergic: pruritic, bilateral
Why do contact-lens wearers need urgent referral if they get conjunctivitis?
Difficult to distinguish between cojunctivitis and microbial keratitis which requires prompt treatment
Which cause of keratitis is associated with contact lens use in the sea/ swimming pools?
Acathamoeba keratitis
How does the management of viral vs bacterial vs allergic conjunctivitis differ?
Viral: nil
Bacterial: chloramphenicol drops
Allergic: antihistamine drops
What classifies as a “corneal abrasion”?
Epithelial breech without keratitis
How can corneal abrasion be investigated?
Fluorescein stains the defect green
How can corneal abrasion be managed?
You just use antibiotic infection prophylaxis (chloramphenicol ointment)
How does a corneal ulcer/keratitis appear?
visible defect + white corneal opacity
Why is corneal ulcer/keratitis an emergency?
It can cause scarring and vision loss
What is the cause of ophthalmic shingles?
CN VI reactivation of shingles
What is Huntchinson’s sign?
Herpes zoster opthalmicus vesicles extending to tip of nose
Indicates nasociliary involvement
Strongly a/w ocular involvement in shingles (anterior uveitis)
How should ophthalmic shingles be managed?
Aciclovir/ Famciclovir PO 7-10d
+/- topical corticosteroids for inflammation
Urgent opthalmology review if ocular involvement
Recall 2 possible complications of ophthalmic shingles?
Post-herpetic neuralgia
Ptosis
Ocular: conjunctivitis, keratitis, episcleritis, anterior uveitis
Which artery is involved in anterior ischaemic optic neuropathy?
Posterior ciliary artery
What is the cause of arteritic anterior ischaemic optic neuropathy?
Giant cell arteritis
What are the 4 main symptoms of optic neuritis?
CRAP DR
Central scomata
RAPD
Acuity loss (unilateral over hours-days)
Pain worse on movement
DR (RD: red desaturation- poor discrimination of colours)
List 3 causes of optic neuritis
Multiple sclerosis (most common)
Diabetes
Syphilis
What investigation should be performed for suspected optic neuritis?
MRI brain + orbits with gadolinium contrast
How should optic neuritis be managed (immediately and ongoing)?
72h Methylprednisolone IV
11d Prednisolone PO
Recovery 4-6w
What is the prognosis for optic neuritis?
MRI: if > 3 white-matter lesions, 5y risk of developing MS is ~50%
Recall the signs and symptoms of vitreous haemorrhage
Small bleeds –> small black dots in vision and ring floaters
Large bleeds –> loss of red reflex, retina not visualised
Fundal photo source: https://www.glycosmedia.com/education/diabetic-retinopathy/diabetic-retinopathy-features-of-diabetes-vitreous-haemorrhage/
What are 5 risk factors for vitreous haemorrhage?
Diabetes - causes angiogenesis (most common)
Trauma
Anticoagulants e.g. Warfarin
Coagulation disorders
Severe short sightedness
What is the best investigation for vitreous haemorrhage?
Brightness scan ultrasonography
How should small vitreous haemorrhages be managed?
They should resorb spontaneously
How should large vitreous haemorrhages be managed?
Vitrectomy
What is the aetiology of retinal detachment?
Holes in retina allow fluid to separate retina from the pigmented epithelium
What is the most common cause of retinal detachment?
Diabetes
due to breaks in the retina due to traction by the vitreous humour
tears may proceed to detachment if left untreated
List 5 RFs for retinal detachment
DM
Myopia
Age
Previous surgery for cataracts (accelerates posterior vitreous detachment)
Eye trauma e.g. boxing
Recall 5 signs and symptoms of retinal detachment
FLOATERS: pigment cells entering vitreous space
FLASHES: traction on retina
FIELD LOSS: curtain/ shadow progressing to centre from periphery
FALL in ACUITY: if macula involved
RAPD: if optic nerve involved
Describe the appearance of the retina on fundoscopy in retinal detachment
Loss of red reflex
Retinal folds: pale, opaque, wrinkled
May appear normal if break is small
Photo: retinal detatchment secondary to horseshoe retinal tear
On the other side of the card is a fundal photo of a central retinal vein occlusion for reference
On the other side of this card is a fundal photo of branch retinal vein occlusion for reference
How should retinal detachment be managed?
Uregent referal to opthalmologist assessment with slit lamp + indirect opthalmoscopy for pigment cells + vitreous haemorrhage
Urgent vitrectomy + gas tamponade with laser coagulation
Differentiate the symptoms of central retinal vs branch retinal vs cilioretinal artery occlusion
Central RAO: sudden painless total loss of vision + RAPD
Branch RAO: sudden painless partial loss of vision with NO RAPD
Ciliretinal AO: painless central vision loss
Recall 3 things that must be done to investigate possible retinal artery occlusion
- CVS RF history
- Temporal artery biopsy
- ESR
Recall some ways of managing retinal artery occlusion
First thing to do is an eyeball massage
Then options include:
- Carbogen therapy (inhalation of 95% O2 and 5% CO2)
- Haemodilution
- Vasodilators
- Measures to decrease IOP
Recall 5 RFs for central retinal vein occlusion
Age
HTN
Cardiovascular disease
Glaucoma
Polycythaemia
What happens in central retinal vein occlusion?
As vein becomes blocked excess fluid + blood leak into retina + appear as severe haemorrhages (“cheese + tomato pizza appearance”)