Ophthalmology Flashcards
(80 cards)
1
Q
What is acute angle-closure glaucoma?
A
Optic neuropathy due in majority to raised intraocular pressure as a result of impaired aqueous outflow.
Ophthalmology emergency.
2
Q
What predisposes someone to acute angle-closure glaucoma?
A
hypermetropia (long-sightedness)
pupillary dilatation
lens growth associated with age
3
Q
What are the features of acute angle-closure glaucoma?
A
- severe pain: may be ocular or headache
- decreased visual acuity
- symptoms worse with mydriasis (e.g. watching TV in a dark room)
- hard, red-eye
- haloes around lights
- semi-dilated non-reacting pupil
- corneal oedema results in dull or hazy cornea
- systemic upset may be seen, such as nausea and vomiting and even abdominal pain
4
Q
What are the investigations for acute angle-closure glaucoma?
A
- tonometry to assess for elevated IOP
- gonioscopy (literally looking, oscopy, at the angle, gonio): a special lens for the slit lamp that allows visualisation of the angle
5
Q
What is the management for acute angle-closure glaucoma?
A
- Emergency ophthalmology referral
- combination eye drops to lower pressure ( direct parasympathetic agent e.g. pilocarpine, beta blocker, alpha 2 agonist).
- IV acetazolamide
- Laser peripheral iridotomy is definitive
6
Q
What is age related macular degeneration (ARMD)?
A
- Most common cause of blindness in the UK
- Degeneration of the central retina (macula) is the key feature with changes usually bilateral.
- ARMD is characterised by degeneration of retinal photoreceptors that results in the formation of drusen which can be seen on fundoscopy and retinal photography. It is more common with advancing age and is more common in females.
7
Q
What are the risk factors for ARMD?
A
Advancing age
smoking
family hx
8
Q
What are the characteristics of dry ARMD?
A
90% cases
Atrophic
Drusen - yellow round spots on Bruch’s membrane
9
Q
What are the characteristics of wet ARMD?
A
10% of cases
also known as exudative or neovascular macular degeneration
characterised by choroidal neovascularisation
leakage of serous fluid and blood can subsequently result in a rapid loss of vision
carries the worst prognosis
10
Q
What are the symptoms of ARMD?
A
- subacute onset of visual loss with:
a reduction in visual acuity, particularly for near field objects- gradual in dry ARMD
- subacute in wet ARMD
- difficulties in dark adaptation with an overall deterioration in vision at night
- fluctuations in visual disturbance which may vary significantly from day to day
- photopsia, (a perception of flickering or flashing lights), and glare around objects
- visual hallucinations may also occur resulting in Charles-Bonnet syndrome
- distortion of line perception may be noted on Amsler grid testing
- fundoscopy reveals the presence of drusen, yellow areas of pigment deposition in the macular area, which may become confluent in late disease to form a macular scar.
- in wet ARMD well demarcated red patches may be seen which represent intra-retinal or sub-retinal fluid leakage or haemorrhage.
11
Q
What are the investigations for ARMD?
A
- slit-lamp microscopy is the initial investigation of choice. usually accompanied by colour fundus photography to provide a baseline against which changes can be identified over time.
- fluorescein angiography is utilised if neovascular ARMD is suspected, as this can guide intervention with anti-VEGF therapy. This may be complemented with indocyanine green angiography to visualise any changes in the choroidal circulation.
- optical coherence tomography is used to visualise the retina in three dimensions because it can reveal areas of disease which aren’t visible using microscopy alone.
12
Q
What is the management for ARMD?
A
- combination of zinc with anti-oxidant vitamins A,C and E
- anti-VEGF agents include ranibizumab, bevacizumab and pegaptanib
- laser photocoagulation does slow progression of ARMD where there is new vessel formation,
13
Q
What are causes of angioid retinal streaks?
A
- pseudoxanthoma elasticum
- Ehler-Danlos syndrome
- Paget’s disease
- sickle-cell anaemia
- acromegaly
14
Q
What is anterior uveitis?
A
- inflammation of the anterior portion of the uvea - iris and ciliary body.
- It is associated with HLA-B27
- Important cause of red eye
15
Q
What are the features of anterior uveitis?
A
- acute onset
- ocular discomfort & pain (may increase with use)
- pupil may be small +/- irregular due to sphincter muscle contraction
- photophobia (often intense)
- blurred vision
- red eye
- lacrimation
- ciliary flush: a ring of red spreading outwards
- hypopyon; describes pus and inflammatory cells in the anterior chamber, often resulting in a visible fluid level
- visual acuity initially normal → impaired
16
Q
What conditions are associated with anterior uveitis?
A
- ankylosing spondylitis
- reactive arthritis
- ulcerative colitis, Crohn’s disease
- Behcet’s disease
- sarcoidosis: bilateral disease may be seen
17
Q
What is the management of anterior uveitis?
A
- urgent review by ophthalmology
- cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
- steroid eye drops
18
Q
What are the features of Argyll-Robertson pupil?
A
- Accommodation Reflex Present (ARP) but Pupillary Reflex Absent (PRA)
- small, irregular pupils
- Sometimes seen in neurosyphilis or diabetes mellitus
19
Q
What is Blepharitis?
A
- inflammation of the eyelid margins
- due to either meibomian gland dysfunction (common, posterior blepharitis) or seborrhoeic dermatitis/staphylococcal infection
- Common in Rosacea.
20
Q
What are the features of blepharitis?
A
- symptoms are usually bilateral
- grittiness and discomfort, particularly around the eyelid margins
- eyes may be sticky in the morning
- eyelid margins may be red. Swollen eyelids may be seen in staphylococcal blepharitis
- styes and chalazions are more common in patients with blepharitis
- secondary conjunctivitis may occur
21
Q
What is the management of Blepharitis?
A
- softening of the lid margin using hot compresses twice a day
- ‘lid hygiene’ - mechanical removal of the debris from lid margins
cotton wool buds dipped in a mixture of cooled boiled water and baby shampoo is often used - artificial tears may be given for symptom relief in people with dry eyes or an abnormal tear film
22
Q
What are the features of central retinal artery occlusion?
A
- sudden unilateral visual loss
- due to thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis)
- relative afferent pupillary defect
- ‘cherry red’ spot on a pale retina
23
Q
What is the management of central retinal artery occlusion?
A
- any underlying conditions should be identified and treated (e.g. intravenous steroids for temporal arteritis)
- if a patient presents acutely then Intraarterial thrombolysis may be attempted but currently, trials show mixed results.
- poor prognosis
24
Q
What are the risk factors for central retinal vein occlusion?
A
- increasing age
- hypertension
- cardiovascular disease
- glaucoma
- polycythaemia
25
What are the features of central retinal vein occlusion?
- sudden, painless reduction or loss of visual acuity, usually unilaterally
- fundoscopy: widespread hyperaemia, severe retinal haemorrhages - 'stormy sunset'
26
What is the management of central retinal vein occlusion?
- the majority of patients are managed conservatively
- indications for treatment in patients with CRVO include:
* macular oedema - intravitreal anti-vascular endothelial growth factor (VEGF) agents
* retinal neovascularization - laser photocoagulation
27
What is the most common cause of blindness in adults aged 35-65?
Diabetic retinopathy
28
What is the pathophysiology of diabetic retinopathy?
Hyperglycaemia is thought to cause increased retinal blood flow and abnormal metabolism in the retinal vessel walls. This precipitates damage to endothelial cells and pericytes
Endothelial dysfunction leads to increased vascular permeability which causes the characteristic exudates seen on fundoscopy. Pericyte dysfunction predisposes to the formation of microaneurysms. Neovasculization is thought to be caused by the production of growth factors in response to retinal ischaemia
29
What are the features of Herpes simplex keratitis?
- Dendritic corneal ulcer
- red, painful eye
- photophobia
- epiphora
- visual acuity may be decreased
- fluorescein staining may show an epithelial ulcer
30
What is the management of herpes simplex keratitis?
- immediate referral to an ophthalmologist
- topical aciclovir
31
What is herpes zoster ophthalmicus?
Reactivation of the varicella-zoster virus in the area supplied by the ophthalmic division of the trigeminal nerve. It accounts for around 10% of case of shingles.
32
What are the features of herpes zoster ophthalmicus?
- vesicular rash around the eye, which may or may not involve the actual eye itself
- Hutchinson's sign: rash on the tip or side of the nose. Indicates nasociliary involvement and is a strong risk factor for ocular involvement
33
What is the management for herpes zoster ophthalmicus?
- oral antiviral treatment for 7-10 days (ideally started within 72 hrs)
- IV antivirals may be given for very severe infection or if the patient is immunocompromised
- topical antiviral treatment is not given in HZO
- topical corticosteroids may be used to treat any secondary inflammation of the eye
- ocular involvement requires urgent ophthalmology review
34
What are the complications of herpes zoster ophthalmicus?
- ocular: conjunctivitis, keratitis, episcleritis, anterior uveitis
- ptosis
- post-herpetic neuralgia
35
What is Holmes-Adie pupil?
- unilateral in 80% of cases
- dilated pupil
- once the pupil has constricted it remains small for an abnormally long time
- slowly reactive to accommodation but very poorly (if at all) to light
- benign condition most commonly seen in women
36
What are the features of Horner's syndrome?
- miosis (small pupil)
- ptosis
- enophthalmos* (sunken eye)
- anhidrosis (loss of sweating one side)
37
What are some causes of anhidrosis of face arm and trunk in Horner's syndrome?
Central lesions:
- Stroke
- Syringomyelia
- Multiple sclerosis
- Tumour
- Encephalitis
38
What are some causes of anhidrosis of face in Horner's syndrome?
Preganglionic lesions:
- Pancoast's tumour
- Thyroidectomy
- Trauma
- Cervical rib
39
What are some causes of no anhidrosis in Horner's syndrome?
Post ganglionic lesions:
- Carotid artery dissection
- Carotid aneurysm
- Cavernous sinus thrombosis
- Cluster headache
40
What are the features of stage I hypertensive retinopathy?
- Arteriolar narrowing and tortuosity
- Increased light reflex - silver wiring
41
What are the features of stage II hypertensive retinopathy?
Arteriovenous nipping
42
What are the features of stage III hypertensive retinopathy?
- Cotton-wool exudates
- Flame and blot haemorrhages
(These may collect around the fovea resulting in a 'macular star')
43
What are the features of stage IV hypertensive retinopathy?
Papilloedema
44
What are causes of keratitis?
- bacterial: typically Staphylococcus aureus, Pseudomonas aeruginosa is seen in contact lens wearers
- fungal
- amoebic: acanthamoebic keratitis
(accounts for around 5% of cases
increased incidence if eye exposure to soil or contaminated water
pain is classically out of proportion to the findings)
- parasitic: onchocercal keratitis ('river blindness')
- viral: herpes simplex keratitis
- environmental: photokeratitis: e.g. welder's arc eye, exposure keratitis, contact lens acute red eye (CLARE)
45
What are the features of keratitis?
- red eye: pain and erythema
- photophobia
- foreign body, gritty sensation
- hypopyon may be seen
46
What is the management of keratitis?
- stop using contact lens until the symptoms have fully resolved
- topical antibiotics
typically quinolones are used first-line
- cycloplegic for pain relief
e.g. cyclopentolate
47
What are the complications of keratitis?
- corneal scarring
- perforation
- endophthalmitis
- visual loss
48
What is dacryocystitis?
- Infection of the lacrimal sac
- watering eye (epiphora)
- swelling and erythema at the inner canthus of the eye
- Mx = systemic antibiotics. IV antibiotics are indicated if there is associated periorbital cellulitis
49
What is Congenital lacrimal duct obstruction?
- affects around 5-10% of newborns.
- bilateral in around 20% of cases
- watering eye (even if not crying)
- secondary infection may occur
- Symptoms resolve in 99% of cases by 12 months of age
50
What are some causes of mydriasis (large pupil)?
- third nerve palsy
- Holmes-Adie pupil
- traumatic iridoplegia
- phaeochromocytoma
- congenital
51
What are some drug causes of mydriasis?
- opical mydriatics: tropicamide, atropine
- sympathomimetic drugs: amphetamines, cocaine
- anticholinergic drugs: tricyclic antidepressants
52
What are some acquired causes of optic atrophy?
- multiple sclerosis
- papilloedema (longstanding)
- raised intraocular pressure (e.g. glaucoma, tumour)
- retinal damage (e.g. choroiditis, retinitis pigmentosa)
- ischaemia
- toxins: tobacco amblyopia, quinine, methanol, arsenic, lead
- nutritional: vitamin B1, B2, B6 and B12 deficiency
53
What are some congenital causes of optic atrophy?
- Friedreich's ataxia
- mitochondrial disorders e.g. Leber's optic atrophy
- DIDMOAD - the association of cranial Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy and Deafness (also known as Wolfram's syndrome)
54
What are some causes of optic neuritis?
- multiple sclerosis: the commonest associated disease
- diabetes
- syphilis
55
What are the features of optic neuritis?
- unilateral decrease in visual acuity over hours or days
- poor discrimination of colours, 'red desaturation'
- pain worse on eye movement
- relative afferent pupillary defect
- central scotoma
56
What is the investigation for optic neuritis?
MRI of the brain and orbits with gadolinium contrast is diagnostic in most cases
57
What is the management of optic neuritis?
high-dose steroids
recovery usually takes 4-6 weeks
58
What is the prognosis of optic neuritis?
MRI: if > 3 white-matter lesions, 5-year risk of developing multiple sclerosis is c. 50%
59
What is orbital cellulitis?
- infection affecting the fat and muscles posterior to the orbital septum, within the orbit but not involving the globe
- usually caused by a spreading upper respiratory tract infection from the sinuses
- high mortality rate
- medical emergency requiring hospital admission and urgent senior review.
60
What are the risk factors for orbital cellulitis?
- Childhood (mean age of hospitalisation 7-12 years)
- Previous sinus infection
- Lack of Haemophilus influenzae type b (Hib) vaccination
- Recent eyelid infection/ insect bite on eyelid (periorbital cellulitis)
- Ear or facial infection
61
What are the features of orbital cellulitis?
- Redness and swelling around the eye
- Severe ocular pain
- Visual disturbance
- Proptosis
- Ophthalmoplegia/pain with eye movements
- Eyelid oedema and ptosis
- Drowsiness +/- Nausea/vomiting in meningeal involvement (Rare)
62
What are the investigation findings in orbital cellulitis?
- FBC: WBC elevated, raised inflammatory markers.
- Decreased vision, afferent pupillary defect, proptosis, dysmotility, oedema, erythema.
- CT with contrast: inflammation of the orbital tissues deep to the septum, sinusitis.
- Blood culture and microbiological swab to determine the organism.
- Most common bacterial causes: Streptococcus, Staphylococcus aureus, Haemophilus influenzae B.
63
What is the management of orbital cellulitis?
Admission to hospital for IV antibiotics
64
What is papilloedema?
optic disc swelling that is caused by increased intracranial pressure. It is almost always bilateral.
65
What are the features of papilloedema seen on fundoscopy?
- Venous engorgement: usually the first sign
- loss of venous pulsation: although many normal patients do not have normal pulsation
- blurring of the optic disc margin
- elevation of optic disc
- loss of the optic cup
- Paton's lines: concentric/radial retinal lines cascading from the optic disc
66
What are the causes of papilloedema?
- space-occupying lesion: neoplastic, vascular
- malignant hypertension
- idiopathic intracranial hypertension
- hydrocephalus
- hypercapnia
Rare:
- hypoparathyroidism and hypocalcaemia
- vitamin A toxicity
67
What is posterior vitreous detachment?
- separation of the vitreous membrane from the retina
- occurs due to natural changes to the vitreous fluid of the eye with ageing
- common condition that does not cause any pain or loss of vision
- important to ensure no retinal detachment
68
What are risk factors for posterior vitreous detachment?
- As people age, the vitreous fluid in the eye becomes less viscous, and thus, does not hold its shape as well. Therefore, it pulls the vitreous membrane away from the retina towards the centre of the eye.
- Highly myopic (near-sighted) patients are also at increased risk of developing posterior vitreous detachment earlier in life. This is because the myopic eye has a longer axial length than an emmetropic eye.
69
What are the features of posterior vitreous detachment?
- The sudden appearance of floaters (occasionally a ring of floaters temporal to central vision)
- Flashes of light in vision
- Blurred vision
- Cobweb across vision
- The appearance of a dark curtain descending down vision (means that there is also retinal detachment)
- Weiss ring on ophthalmoscopy (the detachment of the vitreous membrane around the optic nerve to form a ring-shaped floater).
70
What are the investigations for posterior vitreous detachment?
All patients with suspected vitreous detachment should be examined by an ophthalmologist within 24hours to rule out retinal tears or detachment.
71
What is the management for posterior vitreous detachment?
- Posterior vitreous detachment alone does not cause any permanent loss of vision. Symptoms gradually improve over a period of around 6 months and therefore no treatment is necessary.
- If associated retinal tear or detachment the patient will require surgery to fix this
72
What are the features of relative afferent pupillary defect?
- Marcus-Gunn pupil
- caused by a lesion anterior to the optic chiasm i.e. optic nerve or retina
- Found by 'swinging light' test
73
What are the causes of relative afferent pupillary defect?
- retina: detachment
- optic nerve: optic neuritis e.g. multiple sclerosis
74
What is the anatomical pathway of the pupillary light reflex?
- afferent: retina → optic nerve → lateral geniculate body → midbrain
- efferent: Edinger-Westphal nucleus (midbrain) → oculomotor nerve
75
What are the features of retinitis pigmentosa?
- night blindness is often the initial sign
- tunnel vision due to loss of the peripheral retina (occasionally referred to as funnel vision)
- fundoscopy: black bone spicule-shaped pigmentation in the peripheral retina, mottling of the retinal pigment epithelium
76
What diseases are associated with retinitis pigmentosa?
- Refsum disease: cerebellar ataxia, peripheral neuropathy, deafness, ichthyosis
- Usher syndrome
- abetalipoproteinemia
- Lawrence-Moon-Biedl syndrome
- Kearns-Sayre syndrome
- Alport's syndrome
77
What are some causes of tunnel vision?
- papilloedema
- glaucoma
- retinitis pigmentosa
- choroidoretinitis
- optic atrophy secondary to tabes dorsalis
- hysteria
78
How do prostaglandin analogues work in primary open-angle glaucoma?
Increasing uveoscleral outflow
79
How to beta blockers work in primary open angle glaucoma?
Reducing aqueous production
80
