Ophthalmology Flashcards
What is a Kayser-Fleischer ring?
A dark ring in the eye that appears to encircle the iris
Cause of Kayser-Fleischer rings
Copper deposition in the iris
Usually secondary to Wilson’s disease
Other causes: cholestasis, primary biliary cirrhosis, cryptogenic cirrhosis
What is corneal arcus/arcus senilis?
A white, grey, or blue ring in the corneal margin/at the periphery of the iris
What causes arcus senilis (AKA corneal arcus)?
Cholesterol deposits
i.e. caused by hypercholeseterolaemia
Signs in Grave’s ophthalmopathy
Chemosis
Conjunctival oedema
Exophthalmos
Proptosis
Differentials for a painless acute red eye
Blepharitis Ectropion/Entropion Chalazion Trichiasis Subconjunctival haemorrhage Pterygium Foreign body/trauma
Differentials for a painful acute red eye
Erosion Keratitis Allergic/bactieral/viral conjunctivitis Dry eues Acute angle closure glaucoma Iritis Scleritis
Definition of blepharitis
Inflammation of the eyelid margin
Clinical features of blepharitis
Itching Burning Mild foreign body sensation Tearing Crusting around eyes on waking Eythematous, thickened eyelid margins Crusts and debris within lashes Conjunctival injection or mild mucous discharge
Management of blepharitis
Warm compresses 15 minutes BD (melts oil produced by meibomian glands occluding the orrifice)
Followed by eyelid scrub
May need antibiotic ointment
Definition of a stye
An acute lesion arising from an infected meibomian gland or other sebaceous cyst under the eyelid
AKA hordeola
Definition of a chalazinon
A chronic lesion caused by blockage of meibomain gland leading to granulation tissue formation etc.
Conditions predisoposing to recurrent chalazia
Rosacea
Seborrheic dermatitis
Blepharitis
Diabetes
Management of chalazia and styes
Warm compresses BD
Massage in direction of lashes
Oral antibiotics if associated cellulitis
(conservative measures resolve 50%)
Second-line: intralesional steroid injections
Incision and curettage
Definition of ectropion
eversion of the lower eyelid
Definition of entropion
Inversion of an eyelid
Causes of ectropion
Age-related tissue relaxation
CN VII palsy
Posttraumatic or postsurgical changes
Causes of entropion
Age-related tissue relaxation
Postinfectious or post traumatic changes
Blepharospasm
Management of entropion/ectorpion
Entropion: surgery
Ectropion: tear supplements, occular lubricants at night, surgery for definitive treatment
Definition of subconjunctival haemorrhage
A collection of blood between the sclera and the conjunctiva
Clinical features of subconjunctival haemorrhage
History of trauma or contact (often)
Focal flat red region on ocular surface
Red-brown-yellow-clear natural development
Often no symptoms (may have foreign body sensation)
Definition of pterygium
A triangular wedge of fibrovascular conjunctival tissue that typically starts mediall on the nasal conjunctiva and extends laterally onto the cornea (can cross the iris and pupil)
Definition of pinguecula
A yellow-white appearing lesion on the nasal portion of the eye that does not cross the cornea due to degeneration of collagen fibres in the eye
Definition of keratitis
A general term used to describe corneal inflammation
How many layers are there of the corena
5
Clinical features of keratitis
Pain or sensation of FB
photophobia
Lacrimation
Vision may be reduced if ulcer in visual axis
Herpetic: dendritic ulcer (with terminal bulbs) stained with fluorescein
Management of keratitis
Herpetic: acyclovir ointment hourly for 24h then 5x per day for 14 days
Contact lens-associated: referral to ophthal for scraping of ulcer and commencement of antibiotic treatment
Definition of acute uveitiis
Inflammation of the uveal tract, including the iris, ciliary body and choroid
Conditions predisposing to acute uveitis
Wegener granuomatosis Sarcoidosis Ankylosing spondylitis IBD Behcet's syndrome Use of oral bisphosphonates
Symptoms of iritis (acute anterior uveitis)
Deep pain Redness Photophobia Blurred vision Tearing
Red. visual acuity Constricted, nonresponsibe pupil Leukocytes or flare in anterior chamber KERATIC PRECIPITATES (WBC stuck to posterior surface in cornea) Synechiae (iris adhesions to lens/anterior chamber angle AKA scar) Hypopyon Raised intraocular pressure Band keratopathy
Definition of hypopyon
Pus in anterior chamber
Posterior uveitis presentation
Blurred vision
Floaters
Raised IOP
Disc or macular oedema
Management of iritis
REFER TO OPHTHAL within 24h Mydriatics (red. formation of posteirior synechiae + red. pain from ciliary spasm) Topical steroids Systemic analgesia Work up to rule out secondary causes
Complications of iritis
Inflammatory glaucoma
Posterior synechiae
Peripheral anterior synechiae (adhesion of iris to cornea)
Cataracts
Band keratopathy and macular oedema if chronic
Definition of scleritis
A severe destructive, vision-threatening inflammation involving the deep episclera and sclera
Definition of episcleritis
Inflammation between the sclera and conjunctiva (ring around iris without inflammation)
Clinical presentation of scleritis
Pain (deep, boring ache, severe enough to interfere with sleep and appetite)
Photophobia
Lacrimation
Red eye
Hyperaemic patches beneath bulbar conjunctiva
Normal palpebral conjunctiva
Nocdular: hyperaemic, oedematous, raised nodule
Necrotising: avascular area (white in middle of red)
Management of scleritis
Oral NSAIDs first-line in mild-moderate
Corticosteroids
Immunomodulatory agents (MTX for RA, cyclophosphamide or mycophenolate for Wegener’s)
Surgical indications: perforation, excessive thinning with high risk of rupture, high-grade astigmatism
Management of penetrating eye injury
Immediately protect with non-pressure shield and transfer to ophthal
Management of chemical injury
Copious irrigation for at least 15 minutes
Chlorsig ointment QID, review in 2 days
+/- bandage contact lens
topical antipiotic drops/ointment (pseudomonas coverage if contact lens wearer)
Topical NSAIDs for pain relief
Minor abrasions heal in 24h with symptomatic treatment only
If increase in pain, immediately return!
Definition of open-angle glaucoma
A chronic condition in which the angle between the iris and cornea is not obstructed, but aqeous humour does not adequately drain from the anterior chamber
Definition of acute closed-angle glaucoma
Occurs when the iris bows forward and completely blocks fluid access to the trabecular meshwork - positive feedback loop - rapid increased in IOP, excruciating eye pain and rapid loss of vision
Risk factors for chronic open angle glaucoma
Old age Family history Black race Thinner central corneal thickness Systemic HTN Diabetes Myopia
Normal intraocular pressure
Up to 20mmHg
Clinical features of open angle glaucoma
Symptomatic visual field loss (missing stairs - inf. field, notice portions of words missing when reading, difficulty driving) Abnormal visual field examination Fundoscopy: - Inc. cup:disc ratio - Pitting or notching of rim - vertical elongation of the cup Raised IOP on tonometry
Management of open angle glaucoma
Aim to reduce IOP by 20-40%
Medical agents: topicall preferred - should be applied with passive lid closure and punctal occlusion
Surgical management (if failed medical)
- laser trabeculoplasty
Medications which reduce IOP
Prostaglandin analogues - latanoprost Beta-blockers - timolol Alpha2 selective adrenergic agonistis Cholinergic agonists - pilocarpine Carbonic anhydrase
Presentation of acute angle-closure glaucoma
Severe ocular pain and redness Reduced vision Coloured halos around lights Headache Nausea and vomiting (systemic complaints may be so severe that patients are misdiagnosed as having neurological or GI infections - EXAMINE EYES)
Conjunctival hyperaemia Hazy cornea Fixed mid-dilated pupil Red. visual acuity Raised IOP (usually higher than 40)
Investigation for determinining if open or closed angle glaucoma
Gonioscopy
Management of acute glaucoma
TREAT IMMEDIATELY - OPHTHAL EMERGENCY
- IV Diamox (acetazolamide - osmotic drug)
- Topical eye drops to reduce IOP (timolol, pilocarpine, latanoprost)
- Prompt laser peripheral iridotomy (to open angle) as soon as cornea is clear of inflammation
Risk of bilateral acute glaucoma
Risk of occurring in second eye after presentation in 1 eye is 80%, therefore perform laser iridotomy on both eyes
Definition of retinal detachment
Separation of the neurosensory retina from the retinal pigment epithelium leading to accumulation of subretinal fluid in the potential space between the 2
Risk factors for retinal detachment
Acute retinal tears Past history of contralateral retinal detachment Lattice degeneration Previously undergone cataract surgery Severe myopia Severe ocular trauma Diabetes Stickler syndrome
3 types of retinal detachment
Rhegmatogenous (most common)
Tracitonal
Exudative
Clinical features of retinal detachment
Sudden onset
Flashes of light
Floaters (hazy spots in line of vision which move with eye position)
Peripheral field loss
Loss of central vision (if macula “off” - also separated)
Low IOP
Loss of red reflex - detached retina is grey-white with surface vessels
Management of retinal detachment
(rhegmatogenous)
Ophthal referral - surgery
Causes of retinal artery occlusion
Emboli: - atherosclerotic plaques - Endocarditis - Fat - Atrial myxoma Thrombosis: - Systemic vasculitis (e.g. SLE) - Giant cell arteritis
What is rubeosis iridis
Neovascularisation of the retina or iris
Clinical presentation of retinal artery occlusion
Sudden, painless severe vision loss or visual field defect
Usually unilateral
(if related to GCA, age over 55, headache, tender palpable temporal artery, jaw claudication etc)
Pupil may respond poorly to light
Pale, opaque fundus with cherry red spot fovea on white-yellow background
“Box-carring” of vessels
Retinal oedema (pale retina)
Embolus sometimes visible
Perfusion of central macula following retinal artery occlusion
By presence of cilioretinal artery present in 15% of people
Management of retinal artery occlusion
Treat immediately if occlusion occurred within 24h
Reduce IOP:
- topical timolol
- IV or oral acetazolamide (Diamox)
- intermittent digital massage over closed eyelid
(may lead to dislodge embolus and enter smaller branch of artery - reduce area of retinal ischaemia)
Surgical or laser-mediated embolectomy uncommonly performed
IF GCA: HIGH DOSE SYSTEMIC CORTICOSTEROIDS
Time after occlude vessel before retinal infarction occurs
90 minutes
Risk factors for retinal VEIN occlusion
Age over 65 HTN DM Obesity Hypercoagulable state (Factor V Leiden) Glaucoma REtinal arteriolar abnormalities Arteriosclerotic vascular disease
Clinical features of branch retinal vein occlusion
Some are asymptomatic
Scotoma or visual field defect with blurred or grey vision in ONE area
retinal haemorrhage - focal or wedge-shaped (flame-shaped, dot and blot haemorrhages)
+/- Venous dilation
Visual acuity relatively normal
Clinical features of central retinal vein occlusion
Painless acute onset unilateral BLURRED vision
Ipsilateral relative afferent pupillary defect
Retinal haemorrhage (scattered and diffuse)
Dilated and tortuous veins
Cotton wool spots (50%)
Invesitgation for retinal vein or artery occlusion
Fluorescein angiography
Management of retinal VEIN occlusion
No treatment to restore vision
Treat underlying cause/contributing factors
Retinal laser photocoagulation OR intra-vitreal anti-VEGF to reduce neovascularisation and reduce risk of neovascular glaucoma
Diabetic retinopathy changes
Non-proliferative:
- retinal microaneurysms
- dot and blot haemorrhages
- flame-shaped haemorrhages
- hard exudates
- cotton wool spots
Pre-proliferative
- large blotchy haemorrhages
- cotton wool spots
- beading of retinal veins
- intra-retinal microvascular abnormality
Proliferative (only 5% DM patients will reach this stage)
- Neovascularisation of iris, disc, retina to vitreous
- retinal detachment
Definition of age related macular degeneration
A degenerative disease of the central portion of the retina (the macula) that results primarily in loss of central vision
DRY AKA atrophic
WET AKA neovascular or exudative
Risk factors for age-related macular degeneration
Age Genetic variants Family history Smoking Cardiovascular disease Hypertension Obesity Diet low in omega 3 fatty acids and dark green leafy vegetables
Clinical presentation of dry macular degeneration
Loss of central vision over several years Usually bilateral Central blind spots late in disease Painless Fundoscopy: - Druse Changes in retinal pigment epithelium Areas of chorioretinal (geographic) atrophy
What are drusen
Yellow spots in retina from accumulation of waste products from rods and cones
Clinical presentation of wet age related macular degeneration
RAPID vision loss (days-weeks) Visual distortion is first symptom - central blind spot - curving of straight lines (metamorphosia) Peripheral and colour vision normal USUALLY UNILATERAL Fundoscopic: - localised retinal elevation - retinal oedema - grey-green discoloration under macula - exudates in or around the macula - detachment of retinal pigment epithelium - subretinal haemorrhage in or around the macula
Definition of metamorphosia
Curving of straight lines as in acute (wet) macular degeneration
Early recognition of acute deterioration in macular degeneration
Amsler’s grid (focus on centre dot from a distance of 12 inches)
Management of dry age related macular degeneration
No way to reverse damage
Can reduce risk of developing advanced AMD if have extensive drusen etc. with daily supplements
- zinc oxide
- copper
- vitamin C
- vitamin E
- Lutein - or beta-carotene/vitamin A in people who haven’t smoked (in smokers, beta carotene increases risk of lung cancer)
Management of wet macular degeneration
Daily supplements recommended for dry (zinc, copper, vit C/E/A)
Intravitreal anti-VEGF injection +/- intraocular steroids
Laser photocoagulation
Photodynamic therapy
Supportive measures for those who have vision loss in macular degeneration
Low-vision devices
- magnifiers
- high-power reading glasses
- large computer monitors
- telescopic lenses
Keratoconus
Thinning of the cornea - bulging, causes refractive error treat initially use hard contacts to stop coning
Often from Finnish background
Family history
Differential diagnoses for Flashes
Ophthalmic: - posterior vitreous detachment - retinal tear/hole - retinal detachment - optic neuritis Non-ophthalmic - migraine - postural hypotension - occipital traumas - vertebrobasilar TIAs
Differential diagnoses for floaters
- Vitreous syneresis
- Vitreous haemorrhage
- Posterior vitreous detachment
- Retinal detachment
- Vitritis
- Tear film debris
Drusen v exudates
Drusen are sub retinal deposits of debris from retinal pigment epithelial later
Exudates are intraretinal
Soft v hard drusen
Soft: larger, indistinct margins may slowly enlarge and coalesce
Hard: small, round, discrete spots associated with focal dysfunction of RpE usually innocuous
Pharmacological classes, mechanisms and examples of topical drops for reduction in intraocular pressure
Alpha adrrnergic inhibitors
