Ophthalmology - Vitreous Haemorrhage, Anterior uveitis, Keratitis, Corneal Ulcer Flashcards
Vitreous Haemorrhage (VH) - what is it, and what does it cause?
Vitreous haemorrhage is bleeding into the vitreous humour
It is one of the most common causes of sudden painless loss of vision
It causes disruption to vision to a variable degree, ranging from floaters to complete visual loss
VH - what is the source of the bleeding?
The source of bleeding can be from disruption of any vessel in the retina as well as the extension through the retina from other areas
VH - what are the three most common causes?
Common causes (collectively account for 90% of cases):
- proliferative diabetic retinopathy (over 50%)
- posterior vitreous detachment
- ocular trauma: the most common cause in children and young adults
VH - what are the three clinical features?
Acute or subacute onset of:
- painless visual loss or haze (commonest)
-
red hue in the vision
- floaters or shadows/dark spots in the vision
VH - what two visual defects can you experience?
Reduced visual acuity
Visual field defect - if severe haemorrhage
VH - investigations?
- dilated fundoscopy: may show haemorrhage in the vitreous cavity
- slit-lamp examination: red blood cells in the anterior vitreous
- ultrasound: useful to rule out retinal tear/detachment and if haemorrhage obscures the retina
- fluorescein angiography: to identify neovascularization
- orbital CT: used if open globe injury
Anterior uveitis (AU) - what is it?
Anterior uveitis is one of the important differentials of a red eye
Anterior uveitis describes inflammation of the anterior portion of the uvea - iris and ciliary body
AU - what else can it be referred to as?
It is also referred to as iritis
AU - what are the associated conditions?
- ankylosing spondylitis
- reactive arthritis
- ulcerative colitis, Crohn’s disease
- Behcet’s disease
- sarcoidosis
AU - clinical features?
- acute onset
- ocular discomfort & pain (may increase with use)
- pupil may be small +/- irregular due to sphincter muscle contraction
- photophobia
- blurred vision
- red eye
- lacrimation
- ciliary flush: a ring of red spreading outwards
- hypopyon; describes pus and inflammatory cells in the anterior chamber, often resulting in a visible fluid level
- visual acuity initially normal → impaired
AU - management?
- Urgent review by ophthalmology
- Cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
-
Steroid eye drops
1.
Keratitis - what is it?
Keratitis describes inflammation of the cornea
Keratitis - what are the main causes?
-
bacterial
- typically Staphylococcus aureus
- Pseudomonas aeruginosa is seen in contact lens wearers
- fungal
-
amoebic
- acanthamoebic keratitis
- accounts for around 5% of cases
- increased incidence if eye exposure to soil or contaminated water
- pain is classically out of proportion to the findings
- parasitic: onchocercal keratitis (‘river blindness’)
- viral: herpes simplex keratitis
-
environmental
- exposure keratitis
- contact lens acute red eye (CLARE)
Keratitis - what are the clinical features?
- red eye: pain and erythema
- photophobia
- foreign body, gritty sensation
- hypopyon may be seen
Keratitis - what referral do you have to do for patients that wear contact lens?
- contact lens wearers
- assessing contact lens wearers who present with a painful red eye is difficult
- an accurate diagnosis can only usually be made with a slit-lamp, meaning same-day referral to an eye specialist is usually required to rule out microbial keratitis
