Ophthalmic Pathology Flashcards
Which structures protect the eye?
Bones of orbit
Soft tissues
Tears
Which structures are commonly associated with sudden visual disturbance?
Occular media (transparent: cornea, aqueous humour, lens, vitreous humour)
Retina
Optic nerve
Important historical features in an ophthalmic history?
Onset - rate/severity
Vision affected? - blurred, glare, diplopia (double vision), distorted?
Pain/painless?
Unilateral/bilateral?
Associated features - e.g. headache, nausea?
Name the type of injuries to the orbit?
Orbit fractures
- rim fracture
- blowout fracture - one or more bones surrounding the eye
Name the type of soft tissue injuries in the eye?
Lids - lacerations, malpositions
Orbital fat
How do tears protect the eye?
Lubrication, lavage-blinking
Antimicrobial factors - lactoferrin, lysozyme, Beta-lysis, IgA, IgG, complement, leucocytes
How does conjunctiva protect the eye?
Antimicrobial preotection since it is a lymphoid tissue
What type of pathology can occur with the conjunctiva?
Conjunctivitis - inflammation/infection
- bacterial
- viral
- allergic
- in neonated, exclude possibility of relation to maternal STI
What are the typical presentations of a blow-out fracture?
Intra-orbital pressure increase due to trauma (e.g. punch to the eye)
Floor +/- part of medial wall fracture
Muscle and nerves may become entrapped
What is hyphaema?
Blood in the anterior compartment of the eye (i.e. in front of the iris)
May show as a reddish tinge or may settle as fluid level
How is a blowout fracture treated?
Maxilofacial repair
How is hyphaema managed?
Examine all the structures of the eye
Treat by resting eye, steroid drops +/- mydriatic drops
How to treat perforating trauma?
Surgical repair
Antibiotics
Steroids
+/- mydriatic drops
Typical presentation of sudden vision loss due to the cornea?
Loss of clarity
Acute pressure rise
Corneal infection
Typical presentation of sudden vision loss due to the anterior chamber?
Loss of clarity
Trauma => Hyphaema
Acute infection/inflammation => Pus
Typical presentation of sudden vision loss due to the lens?
Loss of clarity
Acute cataract (rare, diabetes can cause)
Dislocation - trauma, marfans
Typical presentation of sudden vision loss due to the vitreous body?
Loss of clarity
Blood:
normal vessels => vitreous detachment, retinal tear
abnormal vessels => proliferative diabetic retinopathy, neovascular AMD
Pus: acute infection, inflammation, source elsewhere (i.e. uveitis)
Possible reasons of sudden vision loss due to the retina?
Detachment
Macular causes - AMD etc.
Vascular occlusions
- arterial (sclerotic, embolic, arteritic)
- venous (thrombosis)
Possible reasons of sudden vision loss due to the optic nerve?
Optic neuritis (papillitis, retrobulbar neuritis) Ischaemic optic neuropathy
Possible reasons of sudden vision loss due higher pathways?
Stroke
Possible reasons for a dim/absent red reflex
Cataract, opacity behind lens?
What is often a sign with vitreous/retinal detachment?
See lashing lights (also with migraine though - bilateral then though)
What is the most commest cause of blindness and partial sightedness in the western world?
Age-related macular degeneration
Most preventable cause of blindness in the world?
Cataracts - opacification of the lens
