Ophthalmology Flashcards
What is glaucoma?
Refers to the optic nerve damage caused by a rise in intraocular pressure.
Raised intraocular pressure is caused by a blockage in aqueous humour trying to escape the eye.
What are the two types of glaucoma?
Open-angle glaucoma
Acute angle-closure glaucoma
What is the normal intraocular pressure?
10-21mmHg
What is the pathophysiology of open-angle glaucoma?
There is a gradual increase in resistance to flow through the trabecular meshwork.
How does open-angle glaucoma present?
Affects the peripheral vision first –> gradual onset of peripheral vision loss (tunnel vision)
- Fluctuating pain
- Headaches
- Blurred vision
- Halos around lights, particularly at night
How do you measure intraocular pressure?
Non- contact tonometry
Goldmann applanation tonometry
What is recommended by NICE guidelines for all patients needing treatment for open-angle glaucoma?
360º selective laser trabecularplasty
What is the first line medical treatment for open-angle glaucoma?
Prostaglandin analogue (e.g., latanoprost) which increase uveoscleral outflow.
What medications could precipitate acute angle-closure glaucoma?
Adrenergic medications (e.g., noradrenaline)
Anticholinergic medications (e.g., oxybutynin and solifenacin)
Tricyclic antidepressants (e.g., amitriptyline) which have anticholinergic effects
What is the presentation of acute angle-closure glaucoma?
- Severely painful red eye
- Blurred vision
- Halos around light
- Associated headache, nausea and vomiting
What signs would you see on examination with acute angle-closure glaucoma?
- Red eye
- Hazy cornea
- Decreased visual acuity
- Mid-dilated pupil
- Fixed size pupil
- Hard eyeball on gentle palpation
What is the initial management of acute angle-closure glaucoma?
- Lying the patient on their back without a pillow
- Pilocarpine eye drops (2% for blue and 4% for brown eyes)
- Acetazolamide 500mg orally
- Analgesia and an antiemetic if required
What is the definitive treatment for acute angle-closure glaucoma?
Laser iridotomy which involves making a hole in the iris using a laser, which allows the aqueous humour to flow directly from the posterior chamber to the anterior chamber.
What is the management of a patient with signs and symptoms of anterior uveitis?
Urgent ophthalmology review (same day)
What conditions are associated with anterior uveitis?
Ankylosing spondylitis
Reactive arthritis
UC/CD
Behcet’s disease
Sarcoidosis: Bilateral disease may be seen
What is the treatment for orbital cellulitis?
Requires admission to hospital for IV antibiotics due to risk of cavernous sinus thrombosis and intracranial spread
How do you differentiate orbital from preseptal cellulitis?
Reduced visual acuity, proptosis, opthelmoplegia/pain with eye movements are NOT consistent with preseptal cellulitis
What is scleritis?
It is full-thickness inflammation of the sclera. It generally has a non-infective cause and typically causes a red, painful eye.
What is the most commonly associated condition with scleritis?
Rheumatoid arthritis
Also: SLE, Sarcoidosis and granulomatosis with polyangiitis
What is the management for Scleritis?
Urgent assessment and management by ophthalmologist with:
- NSAIDS
- Steroids
- Immunosuppression
What are some common causes of vitreous haemorrhage?
Proliferative diabetic retinopathy (over 50%)
Posterior vitreous detachment
Ocular trauma: The most common cause in children and young adults
What is Glaucoma?
Refers to optic nerve damage caused by a rise in intraocular pressure.
What is the cause of raised intraocular pressure in Glaucoma?
Blockage in the aqueous humour trying to escape the eye
What is the pathophysiology of open-angle glaucoma?
Gradual increase in resistance to flow through the trabecular meshwork. The pressure slowly builds within the eye.
What is the pathophysiology of acute angle-closure glaucoma?
The iris bulges forward and seals off the trabecular meshwork from the anterior chamber, preventing aqueous humour from draining.
Risk factors for open-angle glaucoma?
- Increasing age
- Family history
- Black ethnic origin
- Myopia (nearsightedness)
What is the presentation of Glaucoma?
Affects the peripheral vision first, resulting in gradual onset of peripheral vision loss (tunnel vision).
It can also cause:
- Fluctuating pain
- Headaches
- Blurred vision
- Halos around lights, particularly at night
What is the goldstandard way to measure intraocular pressure?
Goldmann applanation tonometry
When is treatment started for Glaucoma?
When the intraocular pressure is 24mmHg or above
What is the interventional treatment recommended for Open-Angle Glaucoma?
360 degree selective laser trabeculoplasty.
May delay or prevent the need for eye drops.
What is the first line medical treatment for open-angle glaucoma?
Prostaglandin analogue eye drops (e.g. latanoprost).
They increase uveoscleral outflow
What is the most common type of age-related macular degeneration?
Dry (also called non-neovascular) accounts for 90% of cases and wet is the other 10%
What are Drusen and what do they indicate?
Drusen are yellowish deposits of proteins and lipids between the retinal pigment epithelium and Bruch’s membrane.
A few small Drusen can be normal in Older patients.
Frequent and larger drusen can be an early sign of macular degeneration.
What are some of the risk factors for AMD?
- Older age
- Smoking
- Family History
- Cardiovascular disease (e.g. hypertension)
- Obesity
- poor diet, low in vitamins and high in fat
Presentation of AMD?
Visual changes of AMD tend to be unilateral with:
- Gradual loss of central vision
- Reduced visual acuity
- Crooked or wavy appearance to straight lines (metamorphopsia)
Which presents more acutely Wet or Dry AMD?
Wet AMD presents more acutely than dry AMD.
Vision loss can develop within days and progress to complete vision loss within 2-3 years. It often progresses to bilateral disease
What examination findings would you expect in AMD?
- Reduced visual acuity
- Scotoma (enlarged area of vision loss)
- Amsler grid test can be used to assess for the distortion of straight lines seen in AMD
- Drusen may be seen during fundoscopy
What is the management for dry AMD?
- No specific treatment
- Management involves monitoring and reducing the risk of progression by avoiding smoking, controlling BP and giving vitamin supplementation