Ophthalmology Flashcards
Argyll-Robertson pupils?
It is sometimes seen in neurosyphilis. A mnemonic used for the Argyll-Robertson Pupil (ARP) is Accommodation Reflex Present (ARP) but Pupillary Reflex Absent (PRA)
Features
small, irregular pupils
no response to light but there is a response to accommodate
Causes
diabetes mellitus
syphilis
Peripheral curtain over vision + spider webs + flashing lights?
Retinal detachment
Differentiate between Episcleritis and scleritis?
In episcleritis, the injected vessels are mobile when gentle pressure is applied on the sclera. Typically painless
In scleritis, vessels are deeper, hence do not move. Painful
Features of glaucoma?
red eye, severe pain, haloes, ‘semi-dilated’ pupil
Features of uveitis?
red eye, small, fixed oval pupil, ciliary flush
Summary of Subconjunctival haemorrhage
Causes:
Clotting disorders
Systemic HTN
Spontaneous
Strenuous activity, heavy lifting, coughing, WL.
Warfarin, NOACs
1 of BV in conjunctiva ruptures, releases blood in space between sclera + conjunctiva
Sx:
Bright red (due to exposure to ambient O2 levels)
Painless
Doesn’t affect vision
Tx:
Self limiting
Summary of corneal foreign bodies/abrasion?
Corneal injury, vasodilation of scleral vessels = limbal/ciliary flush
Causes: contact lenses (infection w pseudomonas), FB, fingernails, eyelashes, entropion (inward turning eyelid)
Sx: Extreme pain + epiphora (watering) Red FB sensation Blurred vision Photopia Ring of inflam around FB
Complications:
Corneal ulceration + keratitis
Ix:
Fluorescein stain applied. Yellow/ orange colour, collects in abrasions or ulcers
Slit lamp exam
Refer: threat to vision, penetrating eye injury, sig orbital or peri-ocular trauma. FB organic (soils, seeds ↑risk of infection), FB near centre of cornea. Red flags (severe pain, irreg dilated or non-reactive pubils, sig ↓in visual acuity)
Tx: Removed using needle Simple analgesia, lubricating eye drops, eg diclofenac ophthalmic, ketorolac ophthalmic, ibuprofen. Most abrasions heal within 1-2 days. Topical gentamicin in contact wearers
Summary of corneal erosion?
Detachment of corneal epithelium from tissue layers below
Spont due to lack of regen capacity of cornea: corneal dystrophy, corneal uclers, DM, contact lens use, dry eye disease. Injury of cornea
Sudden onset of Sx similar to those of corneal abrasion, typically upon waking or without obvious signs of trauma
Artificial tears + nightly lubrication drops
Summary of corneal ulcers
Open sore of cornea physical, chemical trauma or infection. Usually due to corneal drying + exposure
RF: contact lens overwear/ misuse, prolonged use of steroid eye drops, dry eye syndrome, eyelid disorders, Bells palsy, herpes zoster/ simplex, corneal burns, injuries.
Sx: Grey/white opaque or translucent area on normally clear + transparent corena Pain Redness FB sensation Photophobia Blurry vision Eye watering
Comps:
Can cause LOV, refer
Most commonly occurs as complication of keratitis
Slit lamp + fluorescein
Focal fluorescein staining in cornea
Scape ulcer, MC+S, wide spectrum Abx eye drops
Summary of conjunctivitis?
Inflam of conjunctiva
Bacterial: unilat 1st then bilat
Viral: unilat 1st + bilat due to rubbing + transfer
Types:
Bacterial: discharge, red, sticky in morning, gritty eye
Allergic: red, itchy, swelling, watery discharge. Bilat.
Viral: red, watery, recent URTI, preauricular LN, follicles (bumps on inner part of eyelid
Beware chlamydia infection in eye = refer
Newborns: ophthalmia neonatorum (very severe + dangerous)
Refer if <1mnth as neonatal conjunctivitis can be associated with gonococcal infection + can cause loss of sight/ pneumonia
Ix: Acuity, pupillary responses unaffected May be photophobia Advice not to share towels School exclusion not necessary Contact lenses should be avoided Normally self-limiting in 1-2 wks
Tx:
Bacterial: chloramphenicol drops, 2-3hrly. Topical fusidic acid for pregnant
Allergic: antihistamine drops (cetririzine, loratadine). If LT, topical mast cell stabilisers eg sodium cromoglicate + nedocromil. Topical NSAIDs: ketorolac, diclofenac.
If severe: topical steroids/ ciclosporin
Summary of entropion?
Inward growing eyelid, lashes rubbing inward too.
Common in elderly
Foreign body sensation
Watery eyes
Ectropion: turning out of eyelids
Lubricant eye drops
Summary of blepharitis?
Inflam of eyelids, can be chronic due to build-up of myblobian glands
Seborrheic dermatitis/ staph infection
RF: oily skin, dandruff, pts with rosacea
Sx: Thick secretions, crust/ inflam of eyelid. Bilat Eyelids sticky in morn Red eye Grittiness/discomfort Burning/ itching Dry eye Conjunctival hyperaemia Photophobia ↓vision Styes + chalazions
Topical Abx: topical chloramphenicol oral tetracycline, doxycycline
Clean eyes reg
Soften lid margin using hot compress 2X a day
Mechanical removal of debris from lid margin. Cotton wool dipped in cooled boiled water, baby shampoo
Artificial tears
Topical CS
Summary of pterygium
Triangular fold in sclera or conjunctiva.
Common in tropical countries, UV damage. Inflam, chronic irritation of eye
Wing shaped fibrovascular overgrowth from conjunctiva onto corneal surface
Ocular irritation, burning + tearing
Can be loss of vision if covering a lot, blurred/double vision
Sunglasses + lubricating eye drops. Wide brimmed hats
Artificial tears
Surgery if affecting vision
Summary of keratitis
Inflam of cornea
Bacterial: most common, s aureus, pseudomonas (contact lens)
Viral, acanthamoeba (eye exposure to soil or contaminated water),
Fungal, non-infectious.
Parasitic: onchocercal keratitis (river blindness)
Photokeratitis: cornea damaged by severe UV light, pain, welder’s
Sx:
Bacterial: purulent discharge, hypopyon, round corneal infiltrate/ ulcer.
Pain + redness
FB sensation
Photophobia
XS tearing
Blurry vision
Corneal clouding
Periumbilical injection
Herpes simplex: dendritic/geographic corneal ulcer.
Herpes zoster: ↓corneal sensation, punctate lesion on corneal surface, vesicular eruption on forehead, nose.
Acanthamoeba: contact lenses, corneal ring infiltrate.
Comps: Corneal scarring Perforation Endophthalmitis Visual loss
Ix:
Slit like exam
Emergency, can lead to irreversible vision loss left untreated
Same day referral to eye specialist usually required to rule out microbial keratitis
Stop using contact lenses until Sx resolved
Tx:
Topical broad spec Abx. Quinolones
Oral acyclovir, valacyclovir
Topical steroids
Topical acyclovir
Topical antiseptic eg chlorhexidine with propamidine
Antimycotics: natamycin, nystatin, amphotericin B
Cycloplegic for pain relief e.g. cyclopentolate
Summary of scleritis?
Inflam of full thickness of sclera, not usually caused by infection, contents of eye can pop out.
Systemic inflam condition: RA, SLE, gout, granulomatous with polyangiitis + polymyositis.
Sx: Severe PAIN Pain w eye movement Photophobia Eye watering Gradual ↓ in vision Scleral thinning: may appear violet or blue discolouration of eye.
Most severe, necrotising scleritis (visual impairment but no pain + can lead to perf of sclera).
Ix:
Abnormal pupil reaction to light
Refer, medical emergency
Tx:
NSAIDs + steroids
Immunosuppression appropriate to underlying systemic condition
What is episcleritis?
Inflam of episcleral, outermost layer of sclera, just underneath conjunctiva
Nodular: raised area
Not usually caused by infection
Young + middle aged, inflam disorders RA + IBD
Sx: Localised redness, not diffuse Classically not painful Watering + mild photophobia FB sensation Dilated episcleral vessels.
Ix:
Injected vessels, mobile when gentle pressure is applied to sclera, in scleritis vessels deeper, don’t move
Safety net, benign, self limiting
Tx:
Artificial tears
Phenylephrine drops: blanches conjunctival + episcleral vessels, not scleral. If eye redness improves = episcleritis
Summary of trichiasis?
Lashes rubbing against eye, eyelash grow inwards
Can cause blepharitis
Sx:
FB sensation, grittness, discomfort
Sx usually bilat
Ix:
No referral
Regularly come back
Tx:
Remove with forceps
Fine needle, laser to damage hair follicles.
Summary of primary open angle glaucoma?
↑IOP.
Iris clear of trabecular meshwork. ↑ resistance to outflow. ↑aqueous production/ ↓outflow.
RF: age, genetics, afro Caribbean, myopia, DM, HTN, CS
2° to uveitis, vitreous haem, retinal detachment. Thickening of trabecular lamellae (↓pore size), ↓in no of trabecular cells, ↑ECM in trabecular meshwork.
Sx: Insidious Periph visual loss, nasal scotomas, tunnel vision. ↓visual acuity Optic disc cupping
Ix:
Fundoscopy: optic disc cupping, cup to disc ratio >0.7, optic disc pallor (atrophy), bayonetting of vessels (vessels have breaks as they disappear into deep cup + re-appear at base), cup nitching (usually inf where vessels enter disc), disc haem.
Automated perimetry asses visual field
Slit lamp w pupil dilation, assess optic N + fundus. Optic N head damage.
Measure IOP >24
Tx:
1st: prostaglandin analogue latanoprost.
2nd: BB (timolol), carbonic anhydrase inhib (dorzolamide), sympathomimetic eyedrop (brimonidine, α 2 adrenoceptor agonis).
Miotics: pilocarpine
Laser, periph iridotomy, creates tiny hole in periph iris > aqueous humour flowing to angle.
Surgical trabeculectomy: alternative drainage pathway between ant chamber + subconjunctival space.
Summary of angle closure glaucoma?
RF: hypermetropia (long sightedness), pupillary dilation, lens growth, age, small eyes
Iris covering, chronic/ acutely. Narrow/ closure of ant chamber angle, inadequate drainage, ↑IOP, optic N damage.
Sometimes response to pupil dilatation (periph iris bunches up in angle), resistance ↑, pressure ↑, iris bow forward, closes drainage angle
2°: trabecular meshwork damage, trauma (blood/direct damage), pigment from iris (pigment dispersion syndrome), ocular surgery, ↑episcleral venous pressure, abnormal iris BVs (prolif diabetic retinopathy), steroid induced, cataract (swell, push iris forward to close drainage angle).
Sx: Severe pain: ocular or headache ↓visual acuity Hard red eye Haloes around light Sx worse with mydriasis eg watching TV in dark room Conjunctival redness, Corneal oedema, Cloudy cornea. Photophobia, Eye watering.
Ix: Semi dilated non reacting pupil Fundoscopy Tonometry: ↑IOP, 60 Lie pt back Slit lamp: visualise angle (gonioscopy), assess periph ant chamber configuration + depth, optic nerve head damage visible under slit lamp.
Tx:
Urgent referral, can damage optic nerve.
Combo of eye drops: eg pilocarpine, BB, α 2 agonist
IV acetazolamide
Laser peripheral iridotomy, tiny hole in peripheral iris once acute attack settled
Summary of anterior uveitis/iritis
Inflam of ant portion of uvea, iris + ciliary body.
Associated with HLA-B27
Associated conditions: ankylosing spondylitis, reactive arthritis, UC, CD, Behcet’s disease, sarcoidosis (bilat disease may be seen)
Sx: Red eye Acute onset Ocular discomfort + pain, ↑with use Pupil small, +/- irregular > sphincter muscle contraction Photophobia (intense) Blurred vision Lacrimation Ciliary flush: ring of red spread out Hypopyon: pus + inflam cells in ant chamber, visible fluid level Visual acuity initially normal > impaired Floaters/ flashes
Tx:
Urgent review by ophthalmology
Cycloplegics: dilate pupil which helps relieve pain + photophobia e.g. atropine, cyclopentolate
Steroid eye drop
Summary of vitreous haemorrhage?
Bleeding into vitreous humour.
Disruption of any vessel in retina, extension through retina from other areas
Once bleeding stops, blood typically cleared from retina at 1% per day
Causes: prolif diabetic retinopathy, post vitreous detachment, ocular trauma, bleeding disorders, anticoag, retinal detachment, macular degen, post vitreous detachment
Sx:
Sudden painless loss of vision or haze
Disruption to vision from floaters to complete vision loss
Numerous dark spots
Red hue in vision
Visual field defect
Vitreous appear black against red reflex
May precede a retinal detachment
Ix:
Dilated fundoscopy: haem in vitreous cavity
Slit lamp exam: RBC in ant vitreous
USS: rule out retinal tear/ detach, find cause
Fluorescein angiography: identify neovascularisation
Orbital CT: used if open globe injury
Tx:
Find source of bleeding + stop
Summary of posterior vitreous detachment
Separation of vitreous membrane from retina
Due to natural changes to vitreous fluid of eye with ageing. Becomes less viscous, doesn’t hold shape as well, pulls vitreous membrane away from retina to centre of eye.
Highly myopic (near sighted) pts at risk earlier in life, myopic eye has longer axial length
75% of >65, F>M
No pain/loss of vision
Sudden floaters/ flashes of light
Blurred vision
Cobweb across vision
Retinal detachment: dark curtain descending
Weiss ring on opthalmoscopy: detachment of vitreous membrane around optic nerve to form ring shaped floater
Examined by opthalmologist within 24 hrs.
Sx gradually improve over 6mnths. No Tx
If associated retinal tear or detachment, surgery.
Causes of gradual vision loss?
Cloudy media: cataract, corneal opacity, vitreous haem, chronic glaucoma
Medial clear: ARMD, optic neuropathy, macula dystrophy, CN disease, retinal dystrophy. Optical neuropathy
Causes sudden visual loss?
Painful: angle closure glaucoma, uveitis, corneal ulcer/ keratitis, endophthalmitis, retrobulbar optic neuritis, orbital cellulitis, giant cell arteritis
Painless fleeting: embolic retinal artery occlusion, migraine, ↑IOP, prodrome in giant cell arteritis
Painless prolonged: ischaemic optic neuropathy, retinal a/v occlusion, retinal detachment, ARMD, vitreous haem, orbital disease affecting optic N, IC disease affecting visual pathway. Amaurosis fugax.
