Surgery: Ophthal Flashcards
What are the features of diabetic retinopathy?
Background: venodilation, microaneurysms, hard exudates
Pre-Proliferative: soft exudates
Proliferative: new vessel formation
What are the features of hypertensive retinopathy?
I: arteriolar narrowing + silver wiring
II: AV nipping
III: flame shaped haemorrhages + cotton wool spots
IV: papilloedema = raised IOP
What should you listen for if the pt complains of amaurosis fugax?
Carotid Bruits
What causes pupil constriction?
Acetylcholine - PNS - Circular Muscles
List causes of miosis (4)
Constricted pupil: horners, cluster headaches, Argyll-Robertson, drugs
Horner’s Syndrome Triad
Ptosis
Miosis
Anhidrosis - pre ganglionic affects face, central affects face arms trunk, post ganglionic not affected
What are the causes of Horner’s syndrome?
Pre-Ganglionic Lesion: Trauma Top Rib Thyroidectomy pancoast Tumour
Central Lesion: Stroke Syringomyelia multiple Sclerosis tumour Swelling
Post-Ganglionic Lesion: Carotid Aneurysm Carotid Artery Dissection Cavernous Sinus Thrombosis Cluster Headache
Argyll-Robertson Pupil
Bilateral, accommodates but does not react, neurosyphilis
Damage to the pretectal region in the midbrain
The nickname prostitutes pupil helps remember the O/E and cause
What causes pupil dilation?
Adrenaline - SNS - Dilator Muscles
List causes of mydriasis (6)
Dilated pupil: third nerve palsy, raised ICP, Holmes-Adie, congenital, trauma, drugs
3rd Nerve Palsy Triad
Ptosis
Mydriasis
Divergent strabismus in a down and out position
What are the causes of a 3rd nerve palsy?
Idiopathic
Medical - ischaemia - Pupil Sparing: HTN, DM, MS
Surgical - pressure on PNS - Pupil Dilatation: painful PCOM aneurysm, cavernous sinus thrombosis, tumour, trauma, raised ICP
Think PHD: PCOM, HTN, DM
Holmes-Adie Pupil
Unilateral, Sluggish, Viral
Damage to post ganglionic parasympathetic fibres
Syndrome = pupil + absent ankle and knee reflexes
Which CN has the longest intracranial route?
Abducens
Ddx of Red Eye
Painful: orbital cellulitis, herpes, dryness, keratitis, ulcer, uveitis, scleritis, acute glaucoma
Painless: episcleritis, trichiasis, subconjunctival haemorrhage
Both: blepharitis, viral>allergic>bacterial conjunctivitis, foreign body
Which viruses can cause keratitis? (3)
Herpes simplex, VZV, adenovirus
What can happen when contact wearers go swimming?
Keratitis caused by acanthamoeba
What constitutes the uveal tract? (3)
Iris, ciliary body, choroids
How does corneal pathology and uveitis classically present? (3)
Usually recurring w photophobia, watering, pain
How does orbital cellulitis px? (3)
Unilateral, ophthalmoplegia, proptosis
What can mimic the cobblestone papillae in conjunctivitis?
The use of contacts
Painless + sudden loss of vision
Retinal artery occ: emboli, GCA + fundoscopy shows retinal pallor and cherry red spot
Retinal vein occ: thrombus, myeloma + fundoscopy shows haemorrhages, cotton wool spots, swollen optic disc
Which muscles other than the extraocular are paralysed following a 3rd nerve palsy?
Levator palpebrae superioris + pupillary constrictor
Why is the eye ‘down and out’ in 3rd nerve palsy?
Unopposed SO and LR action
Why is the eye ‘up and in’ in 4th nerve palsy?
Paralysis of SO
What is the anatomy of the retina?
Optic nerve, ganglion cells, bipolar cells, cone/rod, pigment epithelium
Outline the visual pathway
Optic nerve, chiasm, tract, lateral geniculate nucleus in thalamus, meyers loop, primary visual cortices in occipital lobes
What are the components of the physical examination?
Acuity Fields Inspect external eye Accommodation Motility Corneal reflex Pupils Ant segment Fundus IOP Fluorescein Lid Eversion
Hx
Onset Worsening Mono/binocular Contact lens wearer Recent eye surgery Antecedent activities Past visual acuity Unusual sx Other medical conditions - diabetes
Tried any tx
Did someone tell them to come in
Problems w skin, joints, bowels
What requires immediate action?
Acute glaucoma esp >35mmHg -> blockage central retinal artery -> irreversible loss of vision
Infection - ant chamber parathentesis and tap, collect ventrous sample, inject abx
Opthal SVR
Pain Vision Redness Discharge Itching Burning Swelling Photophobia FB sensation Am stickiness
What narrows down ddx for acute red eye?
Painful - abnormal lids, diffuse conjunctival infection, abnormal cornea
Painless - diffuse + localised
What are your ddx if a painful acute red eye w normal lids/cornea and no diffuse conjunctival infection?
Angle closure glaucoma, uveitis, scleritis
What causes discharge?
Blepharitis, stye, dryness, conjunctivitis, corneal trauma
What causes foreign body sensation?
Trichiasis, dryness, conjunctivitis, abrasion, contact lens intolerance, foreign body
What causes itching/burning?
Blepharitis, dryness, conjunctivitis, inflamed pinguecula, keratitis, inflamed pterygium, contact lens intolerance, allergy
What do you need to check w photophobia?
Corneal +/or ant chamber involvement
Ddx of sudden vision loss
Transient: amaurosis fugax
Persistent: vaso-occlusive disorder, optic nerve disorder, retinal detachment
Ocular emerg: medical vs surgical
Med: periorbital cellulitis, conjunctivitis, iritis, glaucoma, central retinal artery occlusion
Surg: orbital fracture, eyelid laceration, extraocular FB, chemical burn, corneal abrasion, hyphema, globe rupture, retinal detachment
Does subconjunctival haemorrhage cause loss of vision?
No: usually resolves by itself in ~2wks
Which conditions predispose to iritis? (2)
Rheumatic Disease + Syphillis
What are the pathognomonic sx of iritis?
Redness, blurred vision, photophobia
Tx for Iritis
Stay in darkened environment, warm compresses, analgesia, steroid drops tailored down over 4wks +/- cycloplegics, F/U
Episcleritis vs Scleritis
The sclera will go white w phenylephrine in episcleritis
What are the effects of phenylephrine in the eye?
Pupil Dilation + Vasoconstriction
How is acute glaucoma classified?
1°/2° open angle glaucoma, 1°/2° angle closure +/- glaucoma, acute angle closure crisis
Mx of acute angle closure crisis
Drops to red production of aqueous and constrict pupil, oral acetazolamide, oral glycerol, IV mannitol, ant chamber paracentesis
Mx of Retinal Detachment
Limit movement by bed rest and eye patches whilst referring to ophthal
What pattern of orbital injury is a/w trauma directly to the globe?
Buckling Effect
Mx of Penetrating FB
A-E, do NOT remove, assess acuity, consider CT head, urgent transfer via ambulance to eye hosp
What does the lens divide the eye into anatomically?
Ant Segment: further split into ant/post chamber relative to the iris
Post Segment: vitreous, retina, uvea, sclera
What is the limbus?
The junction b/w cornea and sclera
What devastating infection can you get following recent eye surgery?
Endophthalmitis
What is the most common bug in contact lens wearers?
Pseudomonas
What abx do you use in contact wearers instead of chloramphenicol?
Quinolones
What causes chronic >6wks conjunctivitis? (2)
Chlamydia + Molluscum
Which bacteria can penetrate an intact corneal surface?
Gonorrhoea
Tx for Blepharitis
Protect ocular surface w lubricant
Artifical tears
Warm compresses
PO doxycycline
What is a chalazion? And tx?
Blocked meibomian gland a/w blepharitis, rosacea, seborrhoeic dermatitis
Tx associations + if persistent incise/curettage
What is characteristic of scleritis?
Pain that wakes them up at night
What is the most common systemic disorder a/w scleritis?
RA
What is the worst thing you can give to a pt with a dendritic ulcer?
Steroids
What is the Hutchinson sign?
When they have herpes zoster vesicles on the tip of their nose, along nasociliary nerve distribution, makes intraocular involvement more likely
Why is a white eye worrying following a chemical injury?
Indicates limbal ischaemia and therefore poor prognosis as the limbal stem cells repopulate the corneal epithelium
Mx of Chemical Injury
Stop hx and immediately wash out until neutralised + forniceal sweep for particulate matter
What are the cardinal signs of orbital>preseptal cellulitis?
Chemosis, reduced ROM, diplopia, proptosis, RAPD
How does acute angle closure glaucoma px?
Painful red eye a/w blurred vision with halos and N+V
What’s the normal range of IOP?
10-21mmHg
What should you give to a pt w acute angle closure glaucoma whilst they’re being transferred to ophthal?
IV/PO 500mg Diamox + get the pt to lie down
What is the sign of retinal detachment?
Single arcuate flash in the corner of vision typically noticed in the dark
What do you want to know about acute painless loss of vision?
Unilateral vs bilateral if unilateral is it monocular vs hemianopia
Ddx: transient loss of vision
Amaurosis fugax, papilloedema, GCA, migraine
At what levator function will a frontalis suspension be required?
<4mm
What is the importance of the medial canthal tendon as a landmark?
Think about the lacrimal gland below and masses above
What is the earliest sign of optic neuritis?
Colour Desaturation
Why do you get a third nerve palsy following a SAH?
Aneurysm of the posterior communicating artery
Which CN lies most medially in the cavernous sinus?
Abducens
What is the mechanism of damage to the 3rd 4th 6th CNs in raised ICP?
They get compressed against the tentorium cerebelli
What structures pass through the optic canal? (3)
Optic nerve, ophthalmic artery, meninges
What are the layers of the cornea? (5)
A-E: anterior epithelium, bowman’s layer, connective stroma, descemet’s membrane, endothelium
Why do you get disciform keratitis?
Hypersensitivity to the viral antigen > infection
What causes nummular keratitis?
Adenovirus
What deficiency would result in Bitot’s spots?
Vit A
List causes of dry eyes
Aqueous def: obstruction, Sjogrens, sarcoidosis, lymphoma, SLE, AIDS, reflex sensory block, meds
Inc evaporation: abnormal lids, meibomian gland dysfunction (blepharitis), goblet cell def (chemical burns, trachoma, SJS, cicatricial pemphigoid, vit A def)
What condition is reflex sensory block seen in?
Diabetes
Myopia
Light is focussed in front of the retina, the refractive power is too great or AP diameter too long, corrected w concave lens
Hypermetropia
Light is focussed behind the retina, the refractive power is too weak or AP diameter too short, corrected w convex lens
Astigmatism
Optical power of eye uneven across different meridians, usually regular ie perpendicular to each other, tx w toric lens / CLs / refractive surg
Presbyopia
Loss of normal accommodation w failure to focus on near objects
What are the types of cataracts?
Nuclear sclerotic, cortical, posterior subcapsular
Which type of cataracts causes nearsightedness?
NS
Which type of cataracts is seen in steroid use?
Posterior Subcapsular
Marfans vs Homocystinuria
Both get subluxed lens but upwards in Marfans and downwards in homocystinuria
Cataract Surgery
Phacoemulsification > ECCE > ICCE
At which point do you start worrying if a child can’t see?
> 3mnths
What is Foster-Kennedy syndrome?
Unilateral visual loss w pale atrophic disc and contralateral papilloedema
What is the common gene mutation in retinoblastoma?
RB1 on Chr13
How do you screen for retinoblastoma? (3)
Red reflex, Hirschberg test, structural abnormalities
What raises concerns about a child’s vision?
Clumsy, photophobic, squint, nystagmus, cloudy cornea
What are causes of a cloudy cornea in a child?
STUMPED
Sclerocornea Tears in Descemet’s Ulcer Metabolic Peter’s Anomaly Endothelial Dystrophy Dermoid
What are the signs of congenital glaucoma?
Corneal clouding, globe enlargement, megalocornea, scleral ring enlargement, tears in descemet’s, rapid cupping
Why must you never miss herpes simplex in a neonate?
Encephalitis
Congenital Glaucoma vs Endothelial Dystrophy
ED: reasonable vision, normal IOP, no inc in corneal diameter
What is the histological definition of the macula?
The region where the ganglion cell layer is more than one cell thick
Which drug causes bulls eye maculopathy?
Hydroxychloroquine: annual retinal screening after five yrs
Ddx for Uveitis
Infection, Sarcoidosis, Lymphoma
Plus IBD if anterior + MS if intermediate
Miller Fisher Syndrome
Variant of GBS: ophthalmoplegia, ataxia, areflexia
What does red desaturation and pain on eye movements suggest?
Optic Neuritis
Does the pupil dilate early/late in a surgical 3rd nerve lesion?
Early as the parasympathetic fibres lie on the outside
What else would you like to measure in a pt w a 3rd nerve palsy?
The BP (HTN) and BM (DM)
What are the causes of a 6th nerve palsy?
The same as 3rd: HTN, DM, MS plus raised ICP
What are the clinical signs of cataracts?
Dec red reflex + lens opacification
Ddx of Cataracts
OAG + Macular Degeneration
Which CN lesion results in a dilated and fixed pupil?
III
Which CN are involved in the corneal reflex?
Afferent V + Efferent VII
Px of Horner’s syndrome
Ptosis, miosis, ipsilateral anhidrosis
Px of third nerve palsy
Ptosis, globe deviation down and out, abnormally dilated pupil (not always present)
Px of sixth nerve palsy
Dec aBduction resulting in binocular horizontal diplopia
Px of Holmes Adie’s pupil
Larger pupil on the affected side which reacts slowly to bright light
NB: no ptosis & normal accommodation reflex
List two causes of Horner’s syndrome
Pancoast tumour & carotid artery dissection
List two causes of carotid artery dissection
Severe whiplash injuries & prolonged neck extension
Gold standard test to exclude carotid artery dissection
Angiography either MRA or CTA
The pupil size in Horner’s syndrome
Smaller
Ddx for poor fundal view
Cataracts, vitreous haemorrhage, corneal scar
RFs for age-related macular degeneration (AMD)
Age, smoking, FHx
Px of AMD
Central visual loss but peripheral and night vision not affected
What is amblyopia?
Poor vision in an eye due to something preventing a clear retinal image being formed in childhood
Most common causes of amblyopia
Uncorrected hypermetropia & constant squint
Myopia
Shortsighted
Hypermetropia
Longsighted
Most common cause of cataract
Senile i.e. age-related
The clinical triad of retinitis pigmentosa
Arteriolar attenuation, bone–spicule peripheral retinal pigmentation, waxy optic disc pallor
Eye changes in diabetes
Retinopathy & maculopathy
Diabetic retinopathy
Dot and blot haemorrhages -> cotton wool spots -> proliferative i.e. neovascularisation
Diabetic maculopathy
Dot and blot haemorrhages & sometimes exudates
What does the presence of exudates in the macular suggest?
Oedema
Other features of retinitis pigmentosa
FHx, night blindness, loss of peripheral vision
How would you formally assess tunnel vision?
Confrontational visual field techniques
Nyctalopia
Night Blindness
Night Blindness
Nyctalopia
Shortsighted
Myopia
Longsighted
Hypermetropia
Causes of pre senile cataract
Steroids, uveitis, diabetes mellitus, high myopia, significant trauma
What is cataracts a/w
Down’s syndrome & retinitis pigmentosa
Which value is important wrt cup to disc ratio
If 0.6 or less probably normal & over 0.6 probably glaucoma
Causes of swollen optic disc
Optic neuritis, anterior ischaemic optic neuropathy inc GCA, papilloedema, severely raised BP
What underlying condition presents w optic neuritis?
Young pt w multiple sclerosis
How to px fundoscopy findings
Think of colour, contour, cupping for disc and then work round the retinal periphery
Most common cause of retinal detachment
Posterior vitreous detachment (PVD) if the vitreous traction is enough to cause a tear
Layers of the eye
Sclera, choroid, retina, vitreous body
Three types of retinal detachment
Rhegmatogenous (tear allowing fluid through), tractional (scar tissue), exudative
Causes of exudative retinal detachment
Inflammation, cancer, Coats disease
Tx of minor retinal detachment
Photocoagulation, cryopexy, retinopexy
Tx of major retinal detachmenty
Scleral buckling & vitrectomy
+/- cryopexy or retinopexy
What is PVD
The vitreous collapses in on itself causing flashes (stops when the vitreous finally separates from the retina) & floaters (which remain for life)
How does retinal detachment px
A shadow in one eye that gradually progresses from edge of vision across the whole field
How does vitreous haemorrhage px
Sudden painless onset of floaters often obscuring vision completely within 10-20mins that usually clears over wks-mnths
How does acute angle closure glaucoma typically px?
Painful red eye w fixed mid-dilated pupil
What is the most common cause of blindness in the UK?
Age Related Macular Degeneration
ARMD: Dry vs Wet
Dry: 90% - characterised by drusen-yellow round spots in Bruch’s membrane
Wet: 10% - characterised by choroidal neovascularisation + worst prognosis
Tx of wet ARMD
Zinc w vits ACE, anti-VEGF agents, laser photocoagulation
What does a dendritic corneal ulcer on slit lamp examination w fluorescein stain?
Herpes Simplex Keratitis
Ix of ARMD
- Slit lamp microscopy: to identify any pigmentary, exudative or haemorrhagic changes
- Fluorescein angiography: if neovascular suspected to guide anti-VEGF therapy
- Ocular coherence tomography: to visualise the retina in 3D
What is the risk of developing MS if >3 white matter lesions on MRI following optic neuritis?
5yrs
List five causes of tunnel vision
Glaucoma Papilloedema Retinitis Pigmentosa Chorioretinitis Tabes Dorsalis
Infective Conjunctivitis: Bacterial vs Viral
Bacterial: purulent discharge + eyes ‘stuck together’ in the am
Viral: serous discharge, recent URTI, preauricular lymph nodes
What drops can be offered for infective conjunctivitis?
Chloramphenicol
What alternative tx can be given to preg women w infective conjunctivitis?
Topical Fusidic Acid
What factors predispose to acute angle closure glaucoma? (3)
Hypermetropia, mydriasis, lens growth a/w age
NB: myopia is a/w primary open angle glaucoma
Mx for AACG
Initial: eye drops (pilocarpine, timolol, apraclonidine) + IV acetazolamide
Definitive: laser peripheral iridotomy
What are the features of episcleritis?
Red eye +/- watering, mild photophobia, mild pain
What drops can be used to differentiate b/w episcleritis vs scleritis?
If the eye redness improves w phenylephrine a dx of episcleritis can be made
Mx of Episcleritis
Consrv +/- artificial tears
What determines the site of lesion in Horner’s syndrome?
Anhydrosis
Face - preganglionic: pancoasts + cervical rib
Plus Arm+Trunk - central: stroke + syringomyelia
Absent - postganglionic: carotid artery dissection
