Ophthalmology Flashcards
What are the functions of the ciliary body?
Produces the aqueous humour, holds the lens in place & contains the ciliary muscles for accommodation.
What is it called when the ciliary muscles get older and contract less and, as a result, you cannot see close up?
Presbyopia (far-sightedness)
If there’s a foreign body in the cornea, and we remove it, how long do we wait to check up again and why?
3 days, due to the corneal epithelium taking 3 days to regenerate.
When looking at something close all of a sudden, what happens to your eyes?
Your eyes converge, pupils get smaller and the lenses get thicker.
What does RAPD mean?
Relative Afferent Pupillary Defect.
Relative = not total
Afferent = optic nerve
Pupillary defect = something has gone wrong with the pupil
When light shines on the affected eye, it dilates instead of constricting.
What is a normal optic disc to cup ratio?
< 0.5
What is photopsia?
Flashes of light or fireworks
What is metamorphopsia?
Distortion of objects or shapes
What is dyschromatopsia?
Change in colour perception
What is the sinus inferior to the eye?
Maxillary sinus
What is the sinus superior to the eye?
Frontal sinus
What is the sinus lateral to the eye?
Temporal sinus
What is the sinus nasally to the eye?
Ethmoidal sinus
What’s the normal range for intraocular pressure?
10 - 21 mmHg
Guess the diagnosis: inflammation and crusting of the eyelids, worse in the heat. You can see punctate epithelial erosions on fleuroscein staining and slit lamp.
Blepharitis
What is a stye?
External; infection of gland of Zeiss OR infection of eyelash follicle
What is a chalazion?
Internal; infection then blockage of Meibomian glands
How do we manage a stye?
Warm compress, cleansing eyelid area
+/- Lubricating drops
Analgesia
Topical antibiotics if there’s conjunctivitis as well
How do we manage a chalazion?
Warm compress, MASSAGE, cleansing eyelid area
+/- Lubricating drops
Analgesia
Topical antibiotics if there’s conjunctivitis as well
Ahmad was doing some woodwork and an insect bit him. The next day, he woke up with unilateral ocular pain and discomfort. When he looked in the mirror, he was shocked to see the affected eye was fully swollen and he couldn’t see properly through it. When you ask him to follow your pen with a ‘H’ motion, he reports no pain, and can see all the right numbers on the Ishihara plates. What is the diagnosis?
Preseptal cellulitis.
Not orbital cellulitis due to the absence of restricted and painful extraocular muscle movement and poor colour vision.
How do we manage preseptal cellulitis?
PO Co-Amoxiclav
but if penicillin-allergic, PO clindamycin
How do we manage orbital cellulitis?
Admit
CT head
IV abx
ENT r/v
What are the red flags of orbital cellulitis?
Orbital involvement
Proptosis
Restricted and painful extraocular muscle movement
Poor visual acuity
Poor colour vision
RAPD
Sepsis
Age < 12 months
Immunocompromised
What’s the diagnosis: Painful visual loss, red desaturation, central scotoma?
Optic neuritis = optic nerve swelling
Which diseases can cause optic neuritis?
MS (most common)
Diabetes
Syphilis
How do we investigate optic neuritis?
MRI of the brain and orbits with gadolinium contrast
Guess the diagnosis: Progressive, worsened central vision, especially at night. Normal examination.
Age-related macular degeneration
How do we manage optic neuritis?
High-dose steroids
How do we investigate AMD and how would we distinguish between dry and wet?
Fundoscopy & OCT.
Fundoscopy:
Dry –> Drusen, small accumulations of extracellular material
Wet –> neovascularization –> exudates leaking and haemorrhaging
OCT:
Dry –> drusen appear as Retinal Pigmented Epithelium deformation or thickening
How do we manage dry AMD?
Supportive:
Smoking cessation
BP control
Weight loss
How do we manage wet AMD?
Conservative:
Smoking cessation
BP control
Weight loss
Medical:
Intravitreal anti-VEGF injections
What are the main painless causes of red eye?
Dry eye (evaporative dry eye = blepharitis)
Conjunctivitis –> viral, bacterial, allergic
Episcleritis
Subconjunctival haemorrhage
What is the most likely diagnosis: Painless, watery, red, gritty eye, crusted shut in the morning & swollen conjunctiva (chemosis)
Conjunctivitis
Guess the diagnosis:
Painless red eye. Clear, watery discharge, lymphadenopathy & common cold symptoms (coryza).
Viral conjunctivitis
How do we manage viral conjunctivitis?
Conservative:
Lubricating eye drops and cool compresses.
Contagious –> no sharing of towels.
If corneal involvement –> photophobia –> referral to ophthalmologist for topical steroids.
What is viral conjunctivitis commonly caused by?
Adenovirus
Guess the diagnosis:
Painless red eye, gritty, severe mucopurulent discharge & conjunctival injection. (Unilateral and non-resolving).
Bacterial conjunctivitis (associated with STIs).
How do we manage bacterial conjunctivitis?
Remove contact lenses
School exclusion not-necessary
Most cases are self-limiting, but topical chloramphenicol drops 2-3 hourly can quicken relief
If pregnant –> topical fusidic acid BD
How do we treat bacterial conjunctivitis associated with STI?
Systemic antibiotic treatment
Refer to genitourinary medicine to evaluate genital disease and contact tracing
Guess the diagnosis:
Painless red eyes, mild puffiness, chemosis, itching, history of asthma.
Allergic conjunctivitis
How do we manage allergic conjunctivitis?
Identify and reduce causative allergen
Topical lubricating eye drops
1st line: topical/systemic antihistamines
2nd line: topical mast cell stabilisers (sodium cromoglicate, nedocromil)
How do we investigate preseptal cellulitis?
CT head
Guess the diagnosis: painful red eye, blurry vision, photophobia, excessive lacrimation, lower back pain improving with exercise.
Acute anterior uveitis
(inflammation of the uvea = inflammation of the iris and ciliary body)
A patient has come in and you’ve suspected acute anterior uveitis. What are your next steps to investigate and what would you expect to see?
Examination of the eyes without fluoroscein and then with: ciliary injection, irregular pupil, corneal oedema, hypopyon
Check eye movements
Slit lamp examination: ciliary flush, aqueous cells in the anterior chamber, flare in the anterior chamber, posterior synechiae
Bloods: routine, HLA-B27 testing, infectious disease screen, serum ACE, etc.
OCT for macular oedema
Spinal X-R for ankylosing spondylitis
C-XR
VDRL
What are posterior synechiae?
Adhesions between the lens and pupil, which distort the shape of the pupil
What is known as “flare”?
Smokey/foggy appearance of the anterior chamber
What is the management for anterior uveitis?
Suspected uveitis –> refer to ophthalmologist for assessment within 24 hours
Topical steroid drops
Pupil dilating drops (cyclopentolate, atropine)
What can cause anterior uveitis?
50% cases idiopathic
50% due to other causes such as ankylosing spondylitis, reactive arthritis, psoriatic arthritis, IBD, syphilis, HIV, etc.
Guess the diagnosis: 3 days history of painful red eye, grittiness, photophobia, PMHx of recurrent cold sores.
Herpes simplex keratitis
How do you investigate Herpes Simplex Keratitis?
Fluoroscopy –> will see an illuminated “K” on the cornea
What are the causes of keratitis for a normal person, a contact lens wearer, and a pt whose eyes have been in contaminated water?
Normal: staph aureus
Contacts: pseudomonas aeruginosa
Contaminated water: acanthamoeba keratitis
How do we manage keratitis?
Urgent review by opthalmologist
For HSK –> topical aciclovir is first line, oral if recurrent or immunocompromised
Guess the diagnosis: Sudden onset sharp pain, rubbed eye until pain disappeared, but it worsened straight after and now is watery. SHx: mechanic, no goggles.
Corneal foreign body and abrasion
How do we investigate a corneal abrasion/foreign body?
Fleuroscein staining + cobalt blue light
How do we manage a corneal foreign body/abrasion?
Remove foreign body
Evert the eyelid to check for any other foreign bodies
Lid sweep
Chloramphenicol QDS
Guess the diagnosis: Painless bright red eye with inflamed-looking blood vessels, mobile on palpation.
Episcleritis
Which one of the two improves with phenylephrine:
Episcleritis
OR
Scleritis?
Episcleritis
How do we manage episcleritis?
Conservative
If symptoms don’t resolve after 2-3 weeks then refer to ophthalmology
Guess the diagnosis: pt had SVT and now is fine, but you notice he has blood pooling in his eye. Weirdly, he’s not in pain.
Subconjunctival haemorrhage (from doing valsalva manoeuvre which is first line for SVT)
How do we manage subconjunctival haemorrhage?
Conservative basically
If INR is raised –> warfarin
Lubricants if gritty
Should resolve by itself, inshaAllah, within a few weeks unless there’s trauma/injury involved
Guess the diagnosis: painful red eye with inflamed-looking blood vessels and a violet hue, vessels don’t move when you touch them with a swab. PMHx of rheumatoid arthritis.
Scleritis
How do we manage scleritis?
Treat underlying cause
Urgent referral to ophthalmology
In rheumatological disease –> high dose steroids
In bacterial infection –> abx
How do we investigate episcleritis?
We don’t
How do we investigate scleritis?
It’s done by the ophthalmologist: it’s sight-threatening
Guess the diagnosis: slightly blurred central vision, floaters, decreased visual acuity, PMHx of T2DM and HTN.
Diabetic retinopathy +/- maculopathy
How do we investigate diabetic retinopathy?
Visual acuity and fundoscopy but gold standard is slit lamp examination or fundus photography
You see a fundoscopic image. How would you grade this diabetic retinopathy:
Two microaneurysms and several dot and blot haemorrhages
Background DR
You see a fundoscopic image. How would you grade this diabetic retinopathy:
Three microaneurysms, lots of hard exudates, two dot and blot haemorrhages, cotton wool spots.
Pre-proliferative DR
You see a fundoscopic image. How would you grade this diabetic retinopathy:
Three microaneurysms, lots of hard exudates, dot and blot haemorrhages in all 4 quadrants, an IRMA and venous beading in half the image.
4-2-1 rule of severe pre-proliferative DR:
4 quadrants: dot and blot haemorrhages
2 quadrants: venous beading
1 quadrant: IRMA
What is an IRMA?
Intraretinal microvascular abnormalities are irregular formations of dilated capillary beds
What is venous beading?
Venous changes are a reliable indicator of generalised ischaemia. They occur when the walls of major retinal veins lose their normal parallel alignment and begin to appear more like a string of sausages.
What are cotton wool spots?
Microinfarction of the retinal nerve fibre layer due to chronic ischaemia.
What are hard exudates?
Deposits of lipids that have leaked onto the retina through damaged vessels.
What are dot and blot haemorrhages?
Damaged vessels may rupture and leak blood.
You see a fundoscopic image. How would you grade this diabetic retinopathy:
Three microaneurysms, hard exudates, dot and blot and vitreous haemorrhages, an IRMA and neovascularisations on the optic nerve.
Proliferative DR
How do we investigate diabetic retinopathy?
HbA1c
OCT
Fluorescein angiography is gold standard for seeing the vessels in the retina
How do we manage DR?
Many require little intervention.
Glycaemic control, blood pressure control, diet changes, exercise, smoking cessation.
Primary intervention in proliferative DR: Laser photocoagulation
also in proliferative: anti-VEGF injections UNLESS stroke or MI in last 3 months.
If persistent vitreous haemorrhage: vitrectomy
Mariam has severe non-proliferative DR and is worried about it progressing to proliferative DR. You assure her there’s nothing more you can do at this stage due to all conservative measures being implemented. She comes in the next week saying she’s now pregnant. Does this change your management?
If pregnant/frequent flyer/only one eye/pre-cataract surgery –> more risk of progression –> laser photocoagulation.
When do we do eye screening for diabetic retinopathy?
Any diabetic over the age of 12.
If high risk of DR, every year.
If DR wasn’t found in the last two tests, it’s every 2 years.
Guess the diagnosis: Pt presents with headache, nausea + vomiting, and PMHx T2DM and HTN. Fundoscopy reveals papilloedema, hard exudates, flame haemorrhages and cotton wool spots.
Hypertensive retinopathy
Papilloedema is a sign of malignant HTN.
How do we manage hypertensive retinopathy?
Control BP
+/- DM control
Guess the diagnosis: severely painful red eye, headaches, low visual acuity, photophobia, haloes around lights, corneal oedema
Acute angle closure glaucoma
This is acutely raised IOP with an obstructed anterior chamber angle (between the cornea and iris)
What kind of examination findings would we expect to see with acute angle closure glaucoma?
Conjunctival injection; diffusely hazy cornea; a fixed, non-reactive, mid-dilated pupil
How do we investigate acute angle closure glaucoma?
Tonometry for high IOP (you may expect >30mmHg)
Gonioscopy
How do we manage acute angle closure glaucoma?
A TIP mnemonic:
Acetazolamide 500 mg IV - carbonic anhydrase inhibitor to open the angle bc it’s closed
Timolol drops - beta blocker to reduce fluid secretion
Iopodine drops - to reduce fluid production
Pilocarpine drops - parasympathetic to increase outflow
BUT
Definitive management = laser iridectomy
Guess the diagnosis: pt referred since the optician saw optic disc cupping in fundoscopy, but pt has no symptoms and no PMHx.
Primary open-angle glaucoma
Syndrome of elevated IOP and optic neuropathy with an open iridocorneal angle
What is a normal IOP?
10 - 20 mmHg
How do we manage primary open angle glaucoma?
360 laser SLT (trabeculoplasty)
PGA latanoprost drops to inc. fluid flow
Dorzolamide carbonic anhydrase inhibitor OR timolol beta blocker
to dec. fluid production
Surgery: trabeculectomy
Regular f/u for IOP via tonometry, optic disc via OCT, visual fields via Humphrey
Guess the diagnosis: elderly gentleman with gradually worsening vision in both eyes and sees glare when driving. No PMHx, smoker.
Cataracts
Opacification of the lens.
What is the most common type of cataract?
Nuclear sclerotic cataract (in the middle of the lens)
Other types are cortical (cortex of the lens) and posterior subcapsular (below that)
How do we manage cataracts?
Phaco + IOL implantation
Phacoemulsification = ultrasound destruction of the old lens
IOL = intraocular lens = new artificial lens
Guess the diagnosis: severely painful red eye, photophobia, floaters, RAPD, history of intraocular surgery (cataracts) in the last 6 weeks.
Endophthalmitis
Infection of the internal structures of the eye –> can lead to permanent loss of vision
How do we manage endophthalmitis?
Go straight to ophthalmology bc it’s an emergency.
They’d need to sample their vitreous fluid, inject intravitreal antibiotics, and admit them for topical and systemic therapy at least.
What kind of burns tend to be more severe for eyes: acidic or alkali burns?
Alkali as it penetrates more deeply into ocular tissues, whereas acid coagulates proteins and forms a protective barrier.
What are some examples of acidic chemicals causing eye burns?
Battery acid, vinegar
What are some examples of alkaline chemicals causing eye burns?
Bleach, ammonia, sodium hydroxide
How do we manage a chemical burn in the eye?
Take a Morgan lens and irrigate and flush the eye and check PH every 10 mins.
Name five ischaemic causes of acute vision loss
Anterior ischaemic optic neuropathy
Central retinal vein occlusion
Central retinal artery occlusion
Retinal detachment
Vitreous haemorrhage
What are the two types of anterior ischaemic optic neuropathy?
Arteritic subtype is to do with temporal arteritis
Non-arteritic subtype is to do with atherosclerosis for example of the small blood vessels supplying the optic nerve
Guess the diagnosis: 51F has sudden loss of vision and sudden headache, diplopia, jaw claudication and PMHx of polymyalgia rheumatica. Reduced colour vision and visual acuity.
Arteritic anterior ischaemic optic neuropathy
If we did an ultrasound of the temporal artery, what would we see that indicates arteritic anterior ischaemic optic neuropathy?
Halo sign due to oedema
How do we manage arteritic anterior ischaemic optic neuropathy?
High-dose systemic steroids
Urgent ophthalmology referral
How do we manage non-arteritic anterior ischaemic optic neuropathy?
We don’t. We just try to prevent it from getting worse.
Guess the diagnosis: A pale swollen disc in a pt over 50
Considered temporal arteritis until proven otherwise.
How do we confirm arteritic anterior ischaemic optic neuropathy?
Temporal artery biopsy
Guess the diagnosis: Sudden painless loss of vision, RAPD, widespread retinal storm haemorrhage on fundoscopy.
Central retinal vein occlusion
Branch retinal vein occlusion could have been the case if it were affecting a limited area of the fundus
How do we manage CRVO?
Conservative
If macular oedema –> intravitreal anti-VEGF injections
If retinal neovascularization –> laser photocoagulation
Guess the diagnosis: sudden painless loss of vision, RAPD, cherry red spot on retina
Central retinal artery occlusion
How do we investigate CRAO?
Carotid artery doppler to see carotid stenosis
C-XR: sarcoidosis and TB in patients under 50
Echo
How do we manage CRAO?
Rule out temporal arteritis
Refer to stroke team
If pt presented within 90 mins, can do ocular massage, re-breathing into a bag, or IV acetazolamide or anterior chamber paracentesis.
300mg aspirin for 14 days for secondary prevention
No car driving for 1 month at least; no commercial driving for 1 year
Guess the diagnosis: sudden, painless loss of vision, starting from the peripheries, floaters and flashes.
Retinal detachment
Retina pulls away from underlying retinal pigment epithelium –> fluid accumulates between the space
How do we investigate retinal detachment?
Visual acuity
IOP
Fundoscopy
B-scan if fundal view is hazy
How do we manage retinal detachment?
Urgent referral to ophthalmology
Surgical: vitrectomy
Guess the diagnosis: sudden painless loss of vision, red hue, gush of floaters, flashes
Vitreous haemorrhage
How would a retinal tear appear on a slit lamp?
Tobacco dust
How do we manage a vitreous haemorrhage?
If no retinal tear/detachment then often resolves in a couple of weeks but needs f/u with safety netting and no heavy lifting advice.
If proliferative vasculopathies –> laser therapy
If posterior vitreous detachment and a long-lasting vitreous haemorrhage/retinal detachment –> surgical
How do we manage posterior vitreous detachment?
Wait and watch
A child comes in with a foreign body in the eye. What kind of imaging must we not use?
MRI due to possibility of metal
What is Seidel’s test?
Fluorescein + cobalt blue light
Check for corneal abrasions, lacerations, trauma, ulcers, etc.
What kind of eye condition is associated with Down’s Syndrome?
Cataracts
