Op stuff you forget Flashcards
Name 4 signs of open angle glaucoma on fundoscopy
Optic disc cupping (cup/disc ratio >0.7)
Optic disc pallor (indicating atrophy)
Bayonetting of vessels
Cup notching
Describe pathophys of OAG
Normally aqueous humour produced by ciliary body flows around lens, though anterior chamber -> trabecular meshwork and canal of schlemm to reach general circulation.
In OAG, increase in resistance in trabecular meshwork, increasing pressure -> cupping of optic disc etc.
Name 2 Ix used in OAG
1st - non-contact tonometry, puff of air.
2nd - Goldmann applanation tonometry, gold std way to measure intraocular pressure.
Describe Mx for OAG (1st line, other options, definitive)
1st line - Latanoprost eye drops. The PG’s increase uveoscleral outflow.
Other options - BB (timolol), carbonic anhydrase inhibitors, sympathomimetics (e.g. brimonidine) all reduce production of aqueous humour.
Definitive - trabeculectomy surgery.
Name 5 causes/RF for AACG
Hypermetropia (long-sightedness)
Pupillary dilatation (e.g. going into dark room)
Age
Excited/stress
Medications that dilate pupil (adrenergics, anticholinergics, TCAs)
Name 5 symptoms of AACG
Acute, red, painful eye.
Sx worse with mydriasis (dilation of pupil)
Decreased visual acuity
Seeing halos around lights
Ocular headache
What 3 things will you see when examining the eye in AACG
Hazy cornea (due to oedema)
Decreased visual acuity
Semi-dilated, non-reacting pupil.
Which 2 Ix need to be done in AACG
Tonometry - to assess for elevated IOP
Gonioscopy - special lens for slit lamp
How do you manage AAGC
Same day emergency ophthalmologist review. Usually Tx w/ combo of eye drops:
- Direct parasympathomimetic (e.g. pilocarpine - contracts eye which opens trabecular meshwork)
- Beta blocker (e.g. timolol - ↓aqueous humour production)
- Alpha-2 agonist (apraclonidine - ↓aqueous humour production and ↑flow)
+ IV acetazolamide (↓aqueous humour production)
Once stable, laser peripheral iridotomy.
What is the most common cause of blindness in adults 35-65?
Diabetic retinopathy
Name 6 signs of diabetic retinopathy on fundoscopy
Retinal/blot haemorrhage
Cotton wool spots
Yellow/white deposits
Microaneurysms
Tortuous capillaries
Neovascularisation
What are the 3 types of diabetic retinopathy and which type of DM are they associated with?
Non-proliferative (background/pre-proliferative) - features of above.
Proliferative - more common in T1DM. Features are retinal neovascularisation.
Diabetic maculopathy - more common in T2DM.
How do you treat the 3 types of diabetic retinopathy?
Maculopathy - intravitreal VEGF if change in visual acuity
Non-proliferative - regular observations.
Proliferative - several options:
- Pan-retinal laser photocoagulation
- Intravitreal VGED inhibitors
- Surgery
6 Cx of diabetic retinopathy
- Retinal detachment
- Vitreous haemorrhage
- Rebeosis iridis
- Optic neuropathy
- Cataracts
- Glacuoma
Name 5 signs of the effects of HTN in the vessels of the retina
Retinal/blot haemorrhage
Cotton wool spots
Silver/copper wiring
Arteriovenous nipping
Hard exudates
Name 3 differentials for acute painLESS red eye
Conjunctivitis - most common by far
Episcleritis
Subconjunctival haemorrhage
Give 7 differentials for acute painFUL red eye
Glaucoma
Anterior uveitis
Scleritis
Corneal abrasions/ulceration
Keratitis
Foreign body
Traumatic/chemical injury
Name 3 symptoms of conjunctivitis
Painless red eye
Itchy/gritty sensation
Discharge from the eye
Can be unilateral/bilateral
How to distinguish bacterial from viral conjunctivitis?
Bacterial - purulent discharge, worse in morning (eyes may be stuck together)
Viral - clear discharge with other Sx of URTI (coryza etc.).
How to treat infective conjunctivitis?
How to treat in <1m olds?
Resolves without treatment
If bacterial suspected, topical chloramphenicol (fusidic acid if pregnant)
<1m - urgent ophthalmology r/v
How to tell if you have allergic conjunctivitis? How is it treated?
Bilateral symptoms, itch is prominent
1st line - antihistamines (oral/topical) like certirizine/loratadine)
2nd line - topical mast-cell stabilisers (nedocromil)
What sight changes are seen with:
- Cataracts
- Glaucoma
- Macular degeneration
Cataracts - generalised reduction in visual acuity and starbursts around lights.
Glaucoma - peripheral loss of vision with halos around lights.
Macular degeneration - central loss of vision with crooked/wavy appearance to straight lines.
How are cataracts diagnosed?
Reduced visual acuity cannot be corrected by refractive correction.
Eye exam normal but slit lamp shows visible cataracts.
What is the main Cx of cataract surgery?
Endophthalmitis - infection of the inner contents of the eye. Treated w/ intravitreal abx.
Describe the pathophysiology of wet and dry AMD
Dry (90%) - degeneration of retinal pigment epithelium retinal and photoreceptors leading to formation of drusen (yellow deposits of proteins). Some drusen normal.
Wet (10%) as dry AMD but there are new vessels from choroid layer into the retina. These can leak fluid/blood = more rapid loss of vision. To do with VEGF.
Describe how wet and dry AMD present
Reduction in central visual acuity
Fluctuations in visual disturbance, varies day to day
May suffer photopsia/wavy appearance of straight lines.
Dry AMD - gradual, over years.
Wet AMD - subacute visual loss (over 2-3 days) then worsens over years.
How are wet and dry AMD diagnosed?
Dry - slit lamp biomicroscopic fundus exam showing medium sized drusen.
Wet - 1st line optical coherence tomography usually diagnostic.
Fluoresceine angiography is 2nd line to diagnose.
Describe management of dry and wet AMD
Dry - no specific treatment, lifestyle to stop progression (smoking cessation best to stop progression). Some evidence of vitamin supplementation.
Wet - anti-VGEF medication (ranibizumab and bevacizumab) injected into vitreous chamber.
Describe 2 key differences between the presentation of scleritis and episcleritis.
Scleritis is painful
Episcleritis is painless
Episcleritis is EPIC, it doesnt hurt!
Episcleritis has mobile injected vessels, scleritis has deeper vessels which do not move.
Describe aetiology, Px, Ix and Mx of epislceritis
2/3rds idiopathic, associated with AID (e.g. RA, vasculitis, IBD).
Acute, unilateral Sx of segmental redness, foreign body sensation, no pain. Injected vessels are mobile.
Ix - phenylephrine drops
Mx - usually self limiting in 1-4 weeks, simple analgesia, cold compress.
Which Ix distinguishes episcleritis from scleritis?
Phenylephrine drops onto conjunctiva
- shrink in episcleritis
- no change in scleritis
Describe aetiology, what is seen on histology, Px, Ix and Mx of scleritis.
More commonly an AID associated.
Histologically there are granulomas (multinucleated epithelioid giant cells)
50% bilateral, acute red, painful eye (on movement), photophobia and eye watering. Redness doesnt move.
Ix - exam and phenylephrine eye drops.
Mx - same day assessment by an ophthalmologist, who may consider NSAIDs, steroids, immunosuppression (treat underlying condition).
Posterior vitreous detachment, describe RF, Px, Ix, Mx
Age and highly myopic (near-sighted people)
Asymptomatic, or painless with spots of vision loss but NO LOSS OF VISION. Classically, sudden appearance of floaters.
Ix - Weiss ring on ophthalmoscopy is diagnostic.
Mx - all need referral to exclude retinal tear/detachment within 24hrs. Otherwise, no Tx.
What are the 2 Cx of PVD
Retinal tears and retinal detachment.
A patient with PVD describes the appearance of a dark curtain descending down vision implies what?
There is also retinal detachment.
Describe what happens in retinal detachment, RF, Px, Ix, Mx
The retina separates from the underlying choroid.
RF - myopia, diabetic retinopathy are main ones. Also posterior PVD.
Px - sudden painless peripheral vision loss like a curtain/shadow. New onset flashes/floaters.
Ix - Fundoscopy - loss of red reflex. Requires urgent referral to an ophthalmologist for Slit lamp, may do US, MRI and CT.
Mx - if just a tear, Mx aims to create adhesions, via laser therapy/cryotherapy.
If detachment, try with virectomy, then above.
Cx - permanent visual loss.
How does vitreous haemorrhage Px?
Like retinal detachment (painless visual loss), but there is a red hue in vision.
Rf - proliferative diabetic retinopathy, PVD, ocular trauma.
Describe the causes of acute and chronic anterior uveitis
Acute - associated with HLA-B27 conditions (AS, IBD, ReA).
Chronic - sarcoidosis, syphilis, Lyme disease, TB, Herpes.
How does anterior uveitis present? Ix, Mx.
Unilateral Sx in a flare of associated disease such as ReA. Sx include
- dull, aching painful red eye.
- Ciliary flush
- miosis (constricted pupil)
- Photophobia (intense)
- Abnormally shaped pupil due to adhesions
- A hypopyon
Needs same day assessment by ophthalmologist. Slit lamp diagnosis.
Mx options are:
- Steroids - oral, topical, IV.
- Cycloplegic-mydriatic medications (cyclopentolate or atropine eye drops)
Cyclopentolate and atropine eye drops can be described as cyclopelgic and mydriatic - what does this mean?
Cycloplegic means paralysing the ciliary muscles.
Mydriatic means dilating the pupils.
There are used in anterior uveitis as they stop spasm causing pain.
What is mydriasis and name 4 common causes
Dilated pupil
1. 3rd nerve palsy
2. Raised ICP
3. Holmes-Adie syndrome
4. Anticholinergics
What is miosis and name 4 causes
Horner syndrome
Cluster headaches
Argyll-Robertson pupil
Opiates, nicotine, pilocarpine.
What are the 3 signs of a 3rd nerve palsy
Ptosis (drooping upper eyelid)
Dilated, non-reactive pupil (mydriasis) (unless medical palsy)
Down and out position of the eye
CN3 supplies most extraocular muscles, LPS and parasympathetic eyes.
Describe medical and surgical causes of a 3rd nerve palsy and what is the difference?
Medical - 3rd nerve palsy with pupil sparing (parasympathetic fibres spared) can be idiopathic, neuritis, DM, HTN.
Surgical third due to physical compression causes mydriasis. Causes are tumour, trauma, cavernous sinus thrombosis, raised ICP.
This is because the parasympathetic fibres run on the outside of the nerve.
What is the triad of Horner syndrome?
Ptosis
Miosis
Anhidrosis
May also have enopthalmos
What is Holmes Adie pupil?
What is Holmes Adie syndrome?
Unilateral dilated pupil (mydriasis) that is sluggish to react to light w/ slow dilation after constriction. Overtime, pupil gets smaller.
Caused by damage to post-ganglionic PSNS fibres w/ unkown cause.
The syndrome is where there is the pupil with absent ankle and knee reflexes.
What is the Argyll-Robertson pupil
A finding w/ neurosyphilis. Constricted pupil that accommodates when focussing on a near object but does not react to light.
Sometimes called “prostitutes pupil” as accommodates but does not react.
What is hypermetropia and myopia risk factors for separately?
Hypermetropia (long sighted) - AACG
Myopia - retinal detachment
