optho Flashcards
(210 cards)
Features of horners syndrome
Miosis
Ptosis
Enopthalmos - sunken in
Anihidrosis
Causes of optic neuritis
MS
Diabetes
Syphilis
Management of optic neuritis
High dose steroids
(Recovery 4-6 weeks)
Features of optic neuritis
Unilateral decrease in visual acuity - over hours or days
Poor discrimination of colours
Pain worse on eye movement
Relative afferent pupillary defect
Central scotoma
Investigation of optic neuritis
MRI of brain with orbits with contrast
Is diagnostic
A 50-year-old woman presents to the emergency department with severe left eye pain over the last 4 hours. She has no changes in her vision, nausea, or vomiting and has a past medical history of rheumatoid arthritis and takes methotrexate. She does not wear any contact lenses.
Her pulse is 92 bpm, her blood pressure is 123/75 mmHg, and she is afebrile. The left eye is deep red and injected throughout. When palpating the eye, the injected vessels do not move and her eye is tender. The right eye is normal and visual fields and acuity are intact.
What is the most likely diagnosis?
Scleritis
Main features = extremely painful, deep red injected eye, patient has systemic connective tissue disease, reduced visual acuity, blurred vision
Management of scleritis
same day assessment by an ophthalmologist
Oral NSAIDS = 1st
Oral glucocorticoids - more severe
Immunosuppressive drugs for resistant cases
What is orbital cellulitis
result of an infection affecting the fat and muscles posterior to the orbital septum - not involving the globe
Usually caused by URTI spreading from sinuses
Is a medical emergency - risk of cavernous sinus thrombosis and intracranial spread
Risk factors of orbital cellulitis
Childhood 7-12 years
Previous sinus infection
No Hib vaccine
Recent eyelid infection
Ear or facial infection
Presentation of orbital cellulitis
Redness and swelling around the eye
Severe ocular pain
Visual disturbance
Proptosis
Opthalmoplegia
Eyelid oedema and ptosis
Drowsiness +/- nausea and vomiting in meningeal involvement
IVX orbital cellulitis
FBC
Clinical examination
CT with contrast
Blood cultures and microbial swab
MXM orbital cellulitis
Hospital admission for IV abx
Leading mechanisms for ocular trauma
Blunt trauma
Penetrating injury
What type of fracture associated with blunt force
Blow out fracture ie fist to the face/squash ball
Structures involved in blow out fracture
herniation of the fat
Tethering of inferior recuts
Infraorbital nerve
Inferior nerve get trapped in inferior wall of orbit
What is hyphaema
Blood in anterior chamber
What medical condition could show a dislocated lense
Marfans
SEIDELS
fluoroscein drops into the eye - would show any aqueous damage
Sympathetic opthalmia
Exposure to intraocular antigens > due to penetrating injury to one eye > but can get auto-immune reaction in both eyes
Inflammation in both eyes > may lead to penetrating blindness
How to remove small foreign body on cornea
slit lamp
Local anaesthetic
Edge of needle > scrape of scoop
Cover with chloramphenicol ointment after
Investigation for intro-ocular foreign body
imaging - x-ray or CT
Chemical injury management
Quick history
Check toxbase if possible
Check pH
Irrigate +++ (2L saline)
Then assess under slit lamp
Ametropia
refractive error present - light focused in front of or behind retina
There are 3 refractive states:
Myopia - before the retina
Emmetropia
Hyperopia - after retina
Emmetropia
Normal vision