Ophthalmology Flashcards
What are some bacterial causes of conjunctivitis in neonates?
Staph Aureus, Neisseria Gonorrhoea, Chlamydia trachomatosis
What are some bacterial causes of conjunctivitis in other ages?
Staph Aureus, Strep pneumoniae, haemophilus influenzae
What are some viral causes of conjunctivitis?
Adenovirus, herpes simplex, herpes zoster
Which types of organism would cause a purulent discharge?
Bacterial
Which types of organism would cause a watery discharge?
Viral
Which type of organism would cause enlarged preauricular lymph nodes?
Viral
How is conjunctivitis investigated/diagnosed?
Do an eye swab
How is bacterial conjunctivitis treated?
Topical chloramphenicol
How is bacterial conjunctivitis treated during pregnancy?
Topical fusidic acid
What does chloramphenicol during pregnancy cause?
Grey baby syndrome
How is allergic conjunctivitis treated?
Antihistamine drops/tablets
2nd line - sodium cromoglycate drops
Who should you suspect chlamydia conjunctivitis in?
Young adults where the disease has been unresponsive to treatment
How does chlamydial conjunctivitis present?
Follicular appearance with subtarsal scarring
How is chlamydial conjunctivitis treated?
Topical oxytetracycline
What is Herpes Zoster Ophthalmicus?
Reactivation of varicella zoster in CNV2
What is Hutchinson’s sign?
Vesicle on tip of nose suggesting nasociliary involvment
How is herpes zoster ophthalmicus treated?
Oral antivirals and steroids
What is keratitis?
Inflammation of the cornea
What are the broad causes?
Infective (bacterial, viral, fungal), autoimmune, vitamin A deficiency
How does keratitis present?
Circumcorneal red eye, photophobia, profuse lacrimation, reduced acuity, stabbing pain
What organism tends to cause a dendritic ulcer?
Herpes simplex virus
How is keratitis investigated?
Corneal scrape
What happens if you use steroids on a dendritic ulcer?
Corneal melt
How is bacterial keratitis treated?
Topical ofloxacin +/- gentamicin and cefotuxamine
How is viral keratitis treated?
Topical aciclovir
How is autoimmune keratitis treated?
Topical steroids
What is orbital cellulitis?
Infection that develops BEHIND the orbital septum
What organisms commonly cause orbital cellulitis?
Strep pneumoniae, staph aureus
How does orbital cellulitis present?
Unilateral red swollen eye lid, difficulty opening the eye, proptosis, reduced vision, reduced eye movements, painful eye movements, ophthalmoplegia
How is orbital cellulitis investigated?
CT sinus and orbit (to rule out abscess)
How is orbital cellulitis managed?
URGENT ADMISSION
IV ceftriaxone, metronidazole and flucloxicillin +/- drainage
What is peri-orbital cellulitis?
Same as orbital cellulitis but NO proptosis, reduction in vision or eye movements
How is peri-orbital cellulitis investigated?
CT sinus and orbit (to rule out abscess)
How is peri-orbital cellulitis managed?
Co-amoxiclav
What is endophthalmitis?
Sight threatening infection of inside the eye
When does endophthalmitis occur?
Usually post eye surgery or penetrating injury
What are some causative organisms of endophthalmitis?
Propionbacterium, staph epidermidis
How is endophthalmitis investigated?
Vitreal/aqueous humour culture
How is endophthalmitis treated?
Intravitreal anikacin and vancomycin
What is chorioretinitis?
Inflammation of choroid and retina (posterior uveitis)
What are some causes of chorioretinitis?
CMV, Toxoplasma, Toxocara
How does chorioretinitis present?
Gradual vision loss, pain, red eyes, floaters, photophobia
‘Pizza Fundus’
CMV
‘Punched out chorioretinal scars’
Toxoplasma
‘Granulomatous damage to retina’
Toxocara
How does a CNIII palsy present?
Eye is down and out
Pupil is dilated
Ptosis
What are some causes of a CNIII palsy?
Diabetes, vasculitis, cavernous sinus thrombosis, amyloidosis, Webers syndrome
What may be the cause in a painful CNIII palsy?
Aneurysm
What muscle does a CNIV palsy affect?
Superior oblique
What are some features of a CNIV palsy?
Intorsion, depression of eye in adduction, abduction weak, vertical diplopia
When may people with CNIV palsy notice diplopia?
On reading/walking up and down stairs (vertical)
What are some causes of a CNIV palsy?
Trauma, diabetes, tumour, idiopathic
What muscle is affected in a CNVI palsy?
Lateral Rectus
What are some features of a CNVI palsy?
Medially deviated eye, unable to abduct, horizontal diplopia
What are some causes of a CNVI palsy?
Microvascular, raised ICP, tumour, congenital
What is internuclear ophthalmoplegia?
Injury/dysfunction of medial longitudinal fasciculatis
What causes internuclear ophthalmoplegia?
MS, stroke
How does internuclear ophthalmoplegia present?
Affected eye cannot adduct
Unaffected eye abducts with nystagmus
Where is the affected structure - unilateral vision loss
Optic nerve (causes - MS, ION)
Where is the affected structure - bitemporal hemianopia
Optic chiasm (causes - pituitary tumour)
Where is the affected structure - homonymous hemianopia
Optic tract (tumour, MS, stroke)