Ophthalmology Flashcards
(112 cards)
Causes of papilloedema
- Space-occupying lesion: neoplastic, vascular
- Malignant hypertension
- Idiopathic intracranial hypertension
- Hydrocephalus
- Hypercapnia
- Hypoparathyroidism and hypocalcaemia
- Vitamin A toxicity
Eyelid problems
- Blepharitis: inflammation of eyelid margins typically leading to red eye
- Stye: infection of glands of eyelids
o Mx: hot compresses and analgesia - Chalazion (Meibomian cyst): retention cyst of Meibomian gland
- Entropion: in-turning of eyelids
- Ectropion: out-turning of eyelids
Differentials for painless acute red eye
o Conjunctivitis
o Episcleritis
o Subconjunctival haemorrhage
Differentials for painful acute red eye
o Acute angle closure Glaucoma
o Anterior uveitis
o Scleritis
o Corneal abrasions or ulceration
o Keratitis
o Foreign body
o Traumatic or chemical injury
o Endophythalmitis
o Dry eyes
Causes of acute visual loss
Optic nerve
- Anterior ischaemic optic neuropathy
- Optic neuritis
Retina
- Central retinal artery occlusion
- Central retinal vein occlusion
What is age related macular degeneration
Degeneration of central retina causing progressive deterioration in vision, often bilateral
Risk factors for macular degeneration
- Advancing age
- Smoking
- Family history (white or Chinese ethnic origin)
- CVD = Hypertension, Dyslipidaemia, Diabetes mellitus
- Obesity (poor diet low in vits and high in fat)
- Females
Classification of macular degeneration
- Dry (90%) = drusen (yellow round spots in Bruch’s membrane), slow progression
- Wet (10%) = choroidal neovascularisation, rapid progression
Presentation of macular degeneration
- Subacute onset of central visual field loss
- Reduction in visual acuity for near field objects
- Difficulties in dark adaptation with overall deterioration in vision at night
- Fluctuations in visual disturbance
- Photopsia (perception of flickering or flashing lights)
- Glare around objects
- Crooked or wavy appearance to straight lines (metamorphopsia)
- Visual hallucinations Charles-Bonnet syndrome
Examination of macular degeneration
- Amsler grid testing distortion of line perception
- Fundoscopy presence of drusen, fluid leakage or haemorrhage
- Atrophy of retinal pigment epithelium
- Degeneration of photoreceptors
- Scotoma (central patch of vision loss)
Investigations of macular degeneration
- Slit lamp microscopy + colour fundus photography
- Fluorescein angiography
- Ocular coherence tomography
Management of macular degeneration
- Refer to ophthalmology for assessment and management
- Zinc with vitamins A, C and E
- Stop smoking
- Blood pressure control
- Anti Vascular endothelial growth factors (ranibizumab, aflibercept, bevacizumab) for wet ARMD ± steroids
- Laser photocoagulation
What is primary open-angle glaucoma
- Optic nerve damage caused by raised intraocular pressure caused by blockage in aqueous humour
- Gradual increase in resistance to flow through trabecular meshwork
Risk factors for open-angle glaucoma
- Increasing age
- Family history
- Black ethnic origin
- Myopia (near-sightedness)
- Hypertension
- Diabetes mellitus
- Corticosteroids
Presentation of open-angle glaucoma
- May be asymptomatic
- Gradual onset of peripheral vision loss
- Fluctuating pain
- Headaches
- Blurred vision
- Halos around lights, particularly at night
Fundoscopy findings in open-angle glaucoma
Optic disc cupping
optic disc pallor
bayonetting of vessels
cup notching
disc haemorrhages
Investigations of open-angle glaucoma
- Non-contact tonometry (screening) measure pressure
- Goldmann applanation tonometry (GS)
- Slit lamp ‘cupping’
- Perimetry visual fields
- Gonioscopy peripheral anterior chamber configuration and depth
- Central corneal thickness
Management of open-angle glaucoma
- Started at intraocular pressure of 24 mmHg or above
- 1st line 360 degree selective laser trabeculoplasty
- 2nd line Prostaglandin analogue eye drops (latanoprost)
- 3rd line beta-blocker (timolol) eye drops, carbonic anhydrase inhibitor eye drops, sympathomietic eye drops
- Trabeculectomy considered in refractory cases
Side effects of prostaglandin analogue eye drops
eyelash growth, eyelid pigmentation, iris pigmentation (browning)
Prevention of open-angle glaucoma
Pts with positive family history should be screened annually from age 40
What is acute angle-closure glaucoma
- Optic neuropathy due to raised intraocular pressure
- Iris bulges forwards and seals off trabecular meshwork from anterior chamber preventing aqueous humour from draining
- Pressure builds in posterior chamber, pushing iris forwards and exacerbating angle closure
- MEDICAL EMERGENCY
Risk factors for angle-closure glaucoma
- Hypermetropia (long-sightedness)
- Pupillary dilatation
- Cataracts
- Lens growth associated with age
- Family history
- Female
- Chinese and East Asian ethnic origin
- Shallow anterior chamber
Triggers of angle-closure glaucoma
- Adrenergic medications (noradrenaline)
- Anticholinergic medications (oxybutynin and solifenacin)
- Tricyclic antidepressants (amitriptyline)
Presentation of angle-closure glaucoma
- Severely painful red eye
- Hazy cornea
- Decreased visual acuity blurred vision
- Symptoms worse with mydriasis (watching TV in dark room)
- Headache
- Haloes around lights
- Semi-dilated non-reacting oval pupil
- Corneal oedema results in dull or hazy cornea
- Hard eyeball on gentle palpation
- Systemic: N+V, abdo pain