Ophthalmology (again lol) Flashcards
afferent pupillary defect
Features
• No direct response but intact consensual response
• Cannot initiate consensual response in contralateral
eye.
• Dilatation on moving light from normal to abnormal eye
Causes
• Total CN II lesion
RAPD
Relative Afferent Pupillary Defect • = Marcus-Gunn Pupil Features • Minor constriction to direct light • Dilatation on moving light from normal to abnormal eye. • RAPD = Marcus Gunn Pupil Causes • Optic neuritis • Optic atrophy • Retinal disease
efferent eye defect
Efferent Defect
Feature
• Dilated pupil does not react to light
• Initiates consensual response in contralateral pupil
• Ophthalmoplegia + ptosis
Cause
• 3rd nerve palsy
§ The pupil is often spared in a vascular lesion
(e.g. DM) as pupillary fibres run in the periphery
ddx fixed dilated pupil
Differential of a fixed dilated pupil • Mydriatics: e.g. tropicamide • Iris trauma • Acute glaucoma • CN3 compression: tumour, coning
Holmes Adie pupil
Holmes-Adie Pupil
Features
• Young woman ¯c sudden blurring of near vision
• Initially unilateral and then bilateral pupil dilatation
§ Dilated pupil has no response to light and
sluggish response to accommodation.
§ A “tonic” pupil
Ix
• Iris shows spontaneous wormy movements on slit-lamp
examination
§ Iris streaming
Cause
• Damage to postganglionic parasympathetic fibres
• Idiopathic: may have viral origin
Holmes-Adie Syndrome
• Tonic pupil + absent knee/ankle jerks + ↓ BP
Horner’s syndrome and cauess
Features: PEAS • Ptosis: partial (superior tarsal muscle) • Enophthalmos • Anhydrosis • Small pupil Causes • Central § MS § Wallenberg’s Lateral Medullary Syndrome • Pre-ganglionic (neck) § Pancoast’s tumour: T1 nerve root lesion § Trauma: CVA insertion or CEA • Post-ganglionic § Cavernous sinus thrombosis § Usually 2O to spreading facial infection via the ophthalmic veins § CN 3, 4, 5, 6 palsies
Argyll Robertson pupil
Argyll Robertson Pupil Features • Small, irregular pupils • Accommodate but doesn’t react to light • Atrophied and depigmented iris Cause • DM • Quaternary syphilis
optic neuropathy signs
Features • ↓ acuity • ↓colour vision (esp. red) • Central scotoma • Pale optic disc • RAPD
optic neuropathy ddx
commonest MS glaucoma congenital Alcohol and Other Toxins • Ethambutol • Lead • B12 deficiency Compression • Neoplasia: optic glioma, pituitary adenoma • Glaucoma • Paget’s Vascular: DM, GCA or thromboembolic Inflammatory: optic neuritis – MS, Devic’s, DM Sarcoid / other granulomatous Infection: herpes zoster, TB, syphilis Oedema: papilloedema Neoplastic infiltration: lymphoma, leukaemia
taking a red eye hx
Vision • Blurred • Distorted • Diplopia • Field defect / Scotoma • Floaters, Flashes Sensation • Irritation • Pain • Itching • Photophobia • FB Appearance • Red: ?distribution • Lump • Puffy lids Discharge • Watering • Sticky • Stringy
Qs to ask o/e for red eye and serious disease signs
Key Examination Questions • Inspect from anterior to posterior • Is acuity affected? • Is the globe painful? • Pupil size and reactivity? • Cornea: intact, cloudy? Use fluorescein Signs of Serious Disease • Photophobia • Poor vision • Corneal fluorescein staining • Abnormal pupil
acute glaucoma vs anterior uveitis vs conjunctivitis
acute glaucoma: most painful, no photophobia, reduced acuity, cornea hazy/cloudy, large pupil, raised IOP
anterior uveitis: medium painful, most photophobia, reduced acuity, normal cornea, small pupil, normal IOP
conjunct: may not have pain, photophobic mildly, rest normal
acute glaucoma
acute glaucoma: most painful, no photophobia, reduced acuity, cornea hazy/cloudy, large pupil, raised IOP
anterior uveitis
anterior uveitis: medium painful, most photophobia, reduced acuity, normal cornea, small pupil, normal IOP
conjuncitviits
conjunct: may not have pain, photophobic mildly, rest normal
acute closed angle glaucoma risk factors and presentation
Acute Closed Angle Glaucoma • Blocked drainage of aqueous from anterior chamber via the canal of Schlemm. • Pupil dilatation (e.g. @ night) worsens the blockage. • Intraocular pressure rises from 15-20 → >60mmHg Risk Factors • Hypermetropia • Shallow ant. chamber • Female • FH • ↑age • Drugs § Anti-cholinergics § Sympathomimetics § TCAs § Anti-histamines Symptoms • Prodrome: rainbow haloes around lights at night-time. • Severe pain ¯c n/v • ↓ acuity and blurred vision
inv and management acute closed angle glaucoma
Examination
• Cloudy cornea c¯ circumcorneal injection
• Fixed, dilated, irregular pupil
• ↑ IOP makes eye feel hard
Ix
• Tonometry: ↑↑ IOP (usually >40mmHg)
Acute Mx: Refer to Ophthalmologist
• Pilocarpine 2-4% drops stat: miosis opens blockage
• Topical β-B (e.g. timolol): ↓ aqueous formation
• Acetazolamide 500mg IV stat: ↓ aqueous formation
• Analgesia and antiemetics
Subsequent Mx
• Bilat YAG peripheral iridotomy once IOP ↓ medically
path, symp, o/e anterior uveitis
Pathophysiology • Uvea is pigmented part of eye and included: iris, ciliary body and choroid. • Iris + ciliary body = anterior uvea • Iris inflammation involves ciliary body too. Symptoms • Acute pain and photophobia • Blurred vision (aqueous precipitates) Examination • Small pupil initially, irregular later • Circumcorneal injection • Hypopyon: pus in anterior chamber • White (keratic) precipitates on back of cornea • Talbots test: ↑pain on convergence
anterior uveitis assoc + treat
Associations (most have no systemic associations)
• Seronegative arthritis: AS, psoriatic, Reiter’s
• Still’s / JIA
• IBD
• Sarcoidosis
• Behcet’s
• Infections: TB, leprosy, syphilis, HSV, CMV, toxo
Mx
• Refer to ophthalmologist
• Prednisolone drops
• Cyclopentolate drops: dilates pupil and prevents
adhesions between iris and lens (synechiae)
episcleritis
Episcleritis • Inflammation below conjunctiva in the episclera Presentation • Localised reddening: can be moved over sclera • Painless / mild discomfort • Acuity preserved Causes • Usually idiopathic • May complicate RA or SLE Rx: Topical or systemic NSAIDs
scleritis
Scleritis • Vasculitis of the sclera Presentation • Severe pain: worse on eye movement • Generalised scleral inflammation § Vessels won’t move over sclera • Conjunctival oedema (chemosis) Causes • Wegener’s • RA • SLE • Vasculitis Mx • Refer to specialist • most need or corticosteroids or immunosuppressants Complications: • Scleromalacia (thinning) → globe perforation
conjunctivitis
Conjunctivitis
Presentation
• Often bilateral ¯c purulent discharge
§ Bacterial: sticky (staph, strep, Haemophilus)
§ Viral: watery
• Discomfort
• Conjunctival injection
§ Vessels may be moved over the sclera
• Acuity, pupil responses and cornea are unaffected.
Causes
• Viral: adenovirus
• Bacterial: staphs, chlamydia, gonococcus
• Allergic
Rx
• Bacterial: chloramphenicol 0.5% ointment
• Allergic: anti-histamine drops: e.g. emedastine
corneal abrasion
Corneal Abrasion • Epithelial breech w/o keratitis • Cause: trauma Symptoms • Pain • Photophobia • Blurred vision Ix • Slit lamp: fluorescein stains defect green Rx • Chloramphenicol ointment for infection prophylaxis
corneal ulcer + keratitis
Corneal Ulcer + Keratitis (corneal inflam)
Causes: bacteria, herpes, fungi, protozoa, RA
• Dendritic ulcer = Herpes simplex
• Acanthamoeba: protazoal infection affecting contact
lens wearers swimming in pools.
Presentation
• Pain, photophobia
• Conjunctival hyperaemia
• ↓ acuity
• White corneal opacity
Risk factors: contact lens wearers
Ix: green ¯c fluorescein on slit lamp
Rx: refer immediately to specialist who will
• Take smears and cultures
• Abx drops, oral/topical aciclovir
• Cycloplegics/mydriatics ease photophobia
• Steroids may worsen symptoms: professionals only
Complications
• Scarring and visual loss
ophthalmic shingles
Ophthalmic Shingles • Zoster of CNV1 • 20% of all Shingles (only commoner in thoracic dermatomes) Presentation • Pain in CNV1 dermatome precedes blistering rash • 40% → keratitis, iritis • Hutchinson’s sign § Nose-tip zoster due to involvement of nasociliary branch. § ↑ chance of globe involvement as nasociliarry nerve also supplies globe • Ophthalmic involvement § Keratitis + corneal ulceration (fluorescein stains) § ± iritis
sudden vision loss Qs
Key Questions
• Headache associated: GCA
• Eye movements hurt: optic neuritis
• Lights / flashes preceding visual loss: detached retina
• Like curtain descending: TIA, GCA
• Poorly controlled DM: vitreous bleed from new vessels
optic neuritis
Optic Neuritis Symptoms • Unilateral loss of acuity over hrs – days • ↓ colour discrimination (dyschromatopsia) • Eye movements may hurt Signs • ↓ acuity • ↓ colour vision • Enlarged blind-spot • Optic disc may be: normal, swollen, blurred • Afferent defect Causes • Multiple sclerosis (45-80% over 15yrs) • DM • Drugs: ethambutol, chloramphenicol • Vitamin deficiency • Infection: zoster, Lyme disease Rx • High-dose methyl-pred IV for 72h • Then oral pred for 11/7
vitreous haemmorhage
Vitreous Haemorrhage Source • New vessels: DM • Retinal tears / detachment / trauma Presentation • Small bleeds → small black dots / ring floaters • Large bleed can obscure vision → no red reflex, retina can’t be visualised Ix • May use B scan US to identify cause Mx • VH undergoes spontaneous absorption • Vitrectomy may be performed in dense VH
central retinal artery occlusion
Central Retinal Artery Occlusion
Presentation
• Dramatic unilateral visual loss in seconds
• Afferent pupil defect (may precede retinal changes)
• Pale retina ¯c cherry-red macula
Causes
• GCA
• Thromboembolism: clot, infective, tumour
Rx
• If seen w/i 6h aim is to ↑ retinal blood flow by ↓ IOP
§ Ocular massage
§ Surgical removal of aqueous
§ Anti-hypertensives (local and systemic)
I think peripheral would be less dramatic with blurring
central retinal vein occlusion
Retinal Vein Occlusion Central • Commoner than arterial occlusion • Causes: arteriosclerosis, ↑BP, DM, polycythaemia • Pres: sudden unilat visual loss ¯c RAPD • Fundus: Stormy Sunset Appearance § Tortuous dilated vessels § Haemorrhages § Cotton wool spots • Complications § Glaucoma § Neovascularisation • Prognosis: possible improvement for 6mo-1yr
check pics
branch retinal vein occlusiono
Branch
• Presentation: unilateral visual loss
• Fundus: segmental fundal changes
• Comps: retinal ischaemia → VEGF release and
neovascularisation (Rx: laser photocoagulation)
check pics
retinal detachement presentation o/e traetment
Retinal Detachment
• Holes/tears in retina allow fluid to separate sensory
retina from retinal pigmented epithelium
• May be 2O to cataract surgery, trauma, DM
Presentation: 4 F’s
• Floaters: numerous, acute onset, “spiders-web”
• Flashes
• Field loss
• Fall in acuity
• Painless
Fundus: grey, opalescent retina, ballooning forwards
Rx
• Urgent surgery
• Vitrectomy + gas tamponade ¯c laser coagulation to
secure the retina
causes transient visual loss
Causes of transient visual loss • Vascular: TIA, migraine • MS • Subacute glaucoma • Papilloedema
causes gradual vision loss
Causes Common • Diabetic retinopathy • ARMD • Cataracts • Open-angle Glaucoma Rarer • Genetic retinal disease: retinitis pigmentosa • Hypertension • Optic atrophy`
age related macular degeneration
Age-Related Macular Degeneration (ARMD) • Commonest cause of blindness >60yrs • 30% of >75yrs will have dry AMD Risk Factors • Smoking • ↑ age • Genetic factors Presentation • Elderly pts. • Central visual loss
dry age related mac degen
Dry ARMD: Geographic Atrophy
• Drusen: fluffy white spots around macula
• Degeneration of macula
• Slow visual decline over 1-2yrs
