Ophthal Flashcards
What is the difference between anterior and posterior uveitis?
Anterior - inflammation of the iris
Posterior - inflammation of the choroid
What are the risk factors for uveitis?
Autoimmune disease
HLA-B27
Intra-ocular lymphoma
Idiopathic
What are the symptoms of anterior uveitis?
Pain
Redness
Photophobia
Diplopia
What are the symptoms of posterior uveitis?
Gradual visual loss
Blurred vision
Absence of anterior symptoms
What is seen on fundoscopy in anterior uveitis?
Diffuse conjunctival injection
Hazy aqueous
Anterior synechiae
Keratitic precipitates on cornea
What is seen on fundoscopy in posterior uveitis?
Inflammatory cells in the vitreous
Oedeomatous optic nerve and disc
What is the treatment of uveitis?
Topical/PO steroids
Cyclopentolate (cycloplegic-mydriatic drug) to paralyse ciliary body, relieve pain and prevent adhesions
What are the features of episcleritis?
Mild pain/discomfort
Grittiness
Watering
What is the most common type of scleritis?
Anterior
What are the risk factors for scleritis?
RA and GPA
CTDs
Sarcoid
UC
What are the features of scleritis?
Severe boring pain radiating to forehead/jaw
Localised or diffuse red eye
Gradual decrease in vision
What are the signs of scleritis?
Reduced visual acuity
Bluish tinge to sclera
Sectoral or diffuse redness
Tender globe
What percentage of scleritis patients have a systemic vasculitis?
15%
How is scleritis diagnosed?
B-scan USS of globe
What is the treatment of scleritis?
PO NSAIDs –> PO pred –> MTX/AZA
If necrotising, skip furst step
What are the 3 types of blepharitis?
Staphylococcal
Seborrhoeic
Meibomian
What are the complications of scleritis?
Scleral thinning
Raised IOP
Retinal detachment
Phthisis (globe atrophy)
What is chalazion?
Meibomian cyst
What is madarosis?
Loss of eyelash
How can you differentitate keratitis from uveitis?
Normal pupillary reaction in keratitis
How is herpes simplex keratitis diagnosed?
Dendritic corneal ulcer - fluoroscein stainin
What is orbital cellulitis?
Infection of the fat and muscles posterior to the orbital septum, within the orbit but not involving the globe
What is periorbital cellulitis?
Infection anterior to the orbital septum
What is the clinical difference between orbital and periorbital cellulitis?
In periorbital - no visual changes, proptosis, ophthalmoplegia, or pain with eye movements
How is orbital cellulitis diagnosed?
CT with contrast
Swab
Blood cultures
What is seen on examination in orbital cellulitis?
Reduced visual acuity
Afferent pupillary defect
Proptosis
Oedema and erythema
Where do the changes of macular degeneration occur?
Central area of retina - macula
What are the characteristics of dry AMD?
Soft drusen (Yellow round spots in Bruch's membrane) Atrophy and changes to pigment of the retinal pigment epithelium (RPE)
What are the characteristics of wet AMD?
New blood vessels grow in from the choriocapillaris under the retina
They spread around the RPE, are fragile and leak easily
Cause disciform scarring
Name 5 risk factors for AMD?
Smoking Age Family history Obesity AMD in one eye
How does AMD present?
Scotoma
Reduced visual acuity particularly for near vision
Decreased contrast, colour, dark adaptation
Photopsia and light glare
Wet - diplopia and distortion
How is dry AMD diagnosed?
Distortion of Amsler grid lines
Fundoscopy - drusen, yellow macular scar, hypo/hyperpigmentation of RPE
How is wet AMD diagnosed?
Well demarcated red patches - retinal/sub RPE haemorrhages
Fluorescein angiography
What does colour fundus photography do?
Records the appearance of the retina
What is the treatment of dry AMD?
Stop smoking
Zinc with vit A, C, E reduce progression in 1/3
For which patients is zinc and anti-oxidants contraindicated?
Smokers - beta-carotene increases risk of lung cancer
What is the treatment of wet AMD?
Intra-vitreal anti-VEGF e.g. ranibizumab
Laser photocoagulation
What is VEGF?
Pro-angiogenic growth factor which stimulates vascular permeability
What is damaged in glaucoma?
Optic nerve head
Loss of retinal ganglion cells and axons
What is raised intra-ocular pressure?
> 21mmHg
What are the causes of secondary glaucoma?
Inflammatory e.g. with uveitis Phacogenic (caused by capsular rupture of the lens) Intra-ocular haemorrhage Steroid induced Traumatic
What are the characteristics of absolute glaucoma?
NO vision
Pupillary reflex lost
Stony eye
Painful +++
What part of the eye produces aqueous humour?
Ciliary body
What is the anterior chamber angle?
Junction of the iris and cornea at the periphery of the anterior chamber
Aqueous humour drains through the trabecular meshwork here
What part of the visual field is affected in glaucoma?
Peripheral –> central
What is the cause of primary open angle glaucoma?
Chronic degenerative obstruction of trabecular meshwork
Painless
What is the cause of closed angle glaucoma?
Iris displaced against cornea which closes iridocorneal angle - aqueous humour cannot flow from posterior to anterior chamber
What are the risk factors for glaucoma?
Raised IOP Myopia Diabetes Positive FH Women - shallow anterior chambers Steroids
Which drugs precipitate acute glaucoma?
Anti-cholinergics
TCAs
How does closed angle glaucoma present?
Redness
Ocular pain
Blurred vision
How does acute closed angle glaucoma present?
Severe pain
Coloured halos around lights
Very high IOP
N+V
What is a direct marker of disease progression in glaucoma?
Diameter of optic disc
How is IOP measured?
Tonometry
What is seen on examination in CAG?
Hazy cornea, redness Non-mid reactive mid-dilated pupil Shallow anterior chambers Closed iridocorneal angles Corneal epithelial oedema
What is the mechanism of topical timolol in glaucoma?
Reduce aqueous secretion by inhibiting beta-adrenoreceptors on the ciliary body
What is the mechanism of topical prostaglandin analogue in glaucoma?
Increase aqueous outflow via the uveoscleral route
What are the side effects and contraindications of topical travaprost?
SE: change in eye colour, thickening/lengthening of eyelashes
CI: severe asthma, aphakia
What is the mechanism of action of topical pilocarpine?
Causes contraction of the ciliary muscle, opens the trabecular meshwork, causes increased outflow of the aqueous humour
What is surgical management of glaucoma?
Laser peripheral iridotomy
Trabeculectomy
What is the condition where there is reactivation of VZV in the area supplied by the ophthalmic division of the trigeminal nerve?
Herpes Zoster ophthalmicus
What is Hutchinson’s sign in herpes zoster ophthalmicus?
Rash on tip or side of nose
Indicates nasociliary involvement
Strong risk factor for ocular involvement
What are 3 causes of optic neuritis?
MS
Diabetes
Syphilis
What are the stages of non-proliferative diabetic retinopathy?
- Background - microaneurysms
- Mod - microaneurysms, intraretinal haemorrhages, cotton wool spots, venous beading
- Severe - the above in all quadrants
What is the treatment of proliferative diabetic retinopathy?
Panretinal photocoagulation
How is diabetic retinopathy diagnosed?
Dilated retinal photography
What is the treatment of diabetic maculopathy?
Focal laser photocoagulation
What are the types of diabetic maculopathy?
Focal/diffuse macular oedema
Ischaemic maculopathy
Clinically significant macular oedema
What is the Keith-Wagener classification of hypertensive retinopathy?
- silver wiring
- AV nipping
- Cotton wool exudates, flame and blot haemorrhages
- Papilloedema
What is seen on fundoscopy in central retinal artery occlusion?
Cherry red spot
How is central retinal vein occlusion differentiated from central retinal artery occlusion?
Vein - severe retinal haemorrhages, disc oedema
Artery - cherry red spot, RAPD
What is the treatment of central retinal vein thrombosis?
Panretinal laser photocoagulation if macular oedema/neovascularisation
What is the treatment of central retinal artery thrombosis?
Ocular massage
Anterior chamber paracentesis/lower IOP
Artery dilatation
What is retinal detachment?
The neurosensory layer of the retina separates from the underlying retinal pigment epithelium
What are 8 risk factors for retinal detachment
Age Jewish Marfans Myopia FH Prev cataract surgery Wet AMD Lattice degeneration
Why is myopia a risk factor for retinal detachment?
Eyeball is longer
Peripheral retina is thinner and more likely to tear
What is the visual loss in retinal detachment?
Peripheral –> central
Flashes and floaters
What are the symptoms of vitreous haemorrhage?
Floaters, but no flashes
What are the symptoms of vitreous detachment?
Floaters and flashes
What are the signs of retinal detachment?
Gross visual defects
Cells in the anterior chamber
Tobacco dust
RAPD
What is a risk factor for vitreous haemorrhage?
Diabetes
What is the pathway of the pupillary light reflex?
Afferent: retina –> optic nerve –> lateral geniculate body –> midbrain
Efferent: Edinger-Westphal nucleus in midbrain –> oculomotor nerve
What is the cause of Marcus-Gunn pupil?
RAPD
Lesion anterior to optic chiasm: optic nerve lesions or severe retinal defect
Retinal detachment
Optic neuritis
What is the swinging light test in RAPD?
Light shone to unaffected eye - both pupils constrict
Light shone to affected eye - less light detected so both pupils dilate
Interruption of the sympathetic nerve supply to the eye is known as?
Horner’s syndrome
What are the symptoms of Horner’s syndrome?
Miosis (constricted pupil)
Ptosis
Enophthalmos (sunken eye)
Anhidrosis (loss of sweating to one side)
In what condition is heterochromia seen?
Congenital horner’s
How can the cause of Horner’s syndrome be differentiated?
Anhidrosis
Face, trunk, arms -> central
Face–> pre-ganglionic
None –> post ganglionic
What are 5 central causes of Horner’s syndrome?
Stroke Syringomyelia MS Tumour Encephalitis
What are 4 pre-ganglionic causes of Horner’s syndrome?
Pancoast’s tumour
Thyroidectomy
Trauma
Cervical rib
What are 3 post-ganglionic causes of Horner’s syndrome?
Carotid artery dissection/aneurysm
Cavernous sinus thrombosis
Cluster headache
How is Horner’s syndrome diagnosed?
Apraclonidine eye drops - causes dilation
Hydroxyamphetamine
Which genetic condition causes night blindness and tunnel vision?
Retinitis pigmentosa
What is seen on fundoscopy in retinitis pigmentosa?
Black bone spicule shaped pigmentation in the peripheral retina, mottling of RPE
What is retinis pigmentosa associated with?
Refsum disease Usher syndrome Abetalipoproteinaemia Lawrence-Moon-Biedl syndrmoe Kearns-Sayer syndrome Alport syndrome
What is the pathophysiology of pseudoxanthoma elasticum?
Calcium accumulates in abnormal elastic fibres
What are the features of pseudoxanthoma?
Yellow lax wrinkled skin Claudication, angina, MV prolapse Cardiomyopathy Angioid streaks and retinal haemorrhages Increased risk of miscarriage
What are 6 differentials for painless loss of vision?
Cataracts PVD or RD Retinal artery/vein occlusion Amaurosis fugax POAG Hydroxychloroquine/isoretinoin
What is seen on fundoscopy in papilloedema?
Venous engorgement Loss of venous pulsation Elevation of optic disc Loss of optic cup Blurring of disc margin Paton's lines
Name 5 causes of papilloedema.
Space occupying lesions Malignant hypertension Vitamin A toxicity Hypercapnia IIH
What are the congenital causes of optic atrophy?
Friedreich’s ataxia
Leber’s optic atrophy
DIDMOAD
What are the acquired causes of optic atrophy?
MS
Raised IOP
Ischaemia
Vit B1, B2, B6, B12 deficiency
What are the characteristics of Holmes-Adie pupil?
Dilated pupil
Once constricted, remains small for an abnormally long time
Slowly reactive to accommodation but very poorly to light
What is Holmes-Adie syndrome associated with?
Absent knee and ankle reflexes
What are 4 causes of mydriasis?
3rd nerve palsy
Holmes Adie pupil
Traumatic iridoplegia
Phaeochromocytoma
What drugs cause mydriasis?
Atropine, tropicamide
Cocaine
TCAs
What is the cause of thyroid eye disease?
Cross-reactivity against shared antigens in thyroid and orbital tissue
Stimulates orbital fibroblasts to produce glycosaminoglycans which causes increased T lymphocytes
What is a risk factor for thyroid eye disease?
Smoking
What is a complication of thyroid eye disease?
Dysthyroid optic neuropathy - loss of colour vision and reduced acuity