Eye pathology Flashcards
Open angle glaucoma
- Resistance as aq humour flows through the trabecular meshwork to get to the canal of schlem, increasing intraocular pressure
*more common in black people
Sx - cupping of optic disc, fluctuating pain, headaches, blurred vision, halos around lights
*Peripheral vision loss
Ix - Check intraocular pressure, fundoscopy, vision field assessment
Mx - Prostaglandin analogue eye drops to increase outflow of aq humour
- Betablocker E.g. timolol to reduce aq humour production
- Normal pressure 10-21mmHg
Acute closed angle glaucoma
- Iris bulges forward, sealing off trabecular meshwork and the canal of schlem, increase intraocular pressure in the anterior chamber which further pushes the iris forward
- women x4 likely, not common in black people, east Asian origin more likely
Sx - cupping of the optic disk, severely red painful eye, blurred vision, halos around lights,
* Pripheral vision loss
* Worse when lights turned off
Ix - red eye, teary, hazy cornea, fixed dilation of affected pupil
**Gonioscopy
Mx - pilocarpine eye drops, acezolamide
Diabetic retinopathy
*Blood vessels in the retina are damaged due to prolonged exposure to high blood sugar levels
* Damage to blood vessel walls and endothelium
Sx - blot haemorrhages (leakage), hard exudates (leakage), micro aneurysm (damage to walls), cotton wool spots (nerve damage), neurovascularisation (growth factors causing new vessels)
Mx - laser photocoagulation, anti VEGF (ranibizumab)
*proliferative if neurovascularisation present
Central retinal artery stenosis
*When something blocks the flow of blood to the retina
- branch of the ophthalmic artery which is a branch of the internal carotid
Cx - embolism from internal carotid, atherosclerosis, giant cell arteritis
* White females >50 at higher risk
Sx - sudden painless loss of vision
Ix - pupil in affected eye constricts more than the healthy eye when light hits, pale retina,
- cherry red spot**
Mx - High does prednisolone
Immediate - ocular massage, remove humour from anterior chamber, dilate artery
Anteroir uveitis
- Inflammation of the anterior portion of the uvea - iris and Hillary body
- 50% associated with a systemic condition
- Associated with HLA B27
Sx - acute onset, gradual reduced vision, pain, small and irregular pupil, photophobia, blurred vision, red eye
**Pus in anterior chamber
Mx - Urgent review to ophthalmology
- Atropine drops to dilate pupils and relive pain
- steroid drops
Normal fundoscopy
- cup ratio - <0.6 - glaucoma increases
- colour - bright orange
- clear margins - blurring shows swollen optic nerve
*quadrants - Superior and inferior nasal and temporal
Optic neuritis
- Painful loss of vision in 1 eye (gradual)
Cx - inflammation of optic nerve, causing papillodema
Mx - timolol to reduce pressure
- acteazolamide
- thrombolytics if clot
Central retinal venous occlusion
- Less sudden painless loss of vision
Cx - blockage
Sx/Ix - redness, tortuous vessels, cotton wool spots, papillodema, blurry vision
*Pizza/cake appearance
Mx - Anti VEGF
Retinal detachment
- Flashing lights worse open eye movements in temporal area
- curtain moving in from periphery to centre
- painless loss of vision
Cx - poor diabetes, high BP, trauma
Mx - surgery - pneumatic retinopexy
- vitrectomy
Macular degeneration
- Age related reduction in visual acuity
Ix - presence of drusen, and yellow pigmentation
* Central vision loss
Dry - drusen
Wet - neurovascularisation
Mx - Vitamin supplements
- Anti VEGF
Blephoritis
- Inflammation of the eyelid
Sx - itching, redness, dry,…
Scleritis vs epilscleritis
- Pain in scleritis
- No pain in episcleritis
Sx - Both red watering eye
- Congenital watery eye
- Nasolacrimal clot obstruction
- Resolves in a year
Vitreous haemorrhage
- Diabetic sudden loss of vision
Sx - dark floaters, reduced vision for weeks
- sudden loss of vision
- haemorrhage obscuring the fungus
