Eye pathology

Question 1

Open angle glaucoma

Answer 1

• 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, peripheral vision loss till tunnel vision, fluctuating pain, headaches, blurred vision, halos around lights

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

Question 2

Acute closed angle glaucoma

Answer 2

• 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, headaches, nausea and vomiting, worse in dark

Ix - red eye, teary, hazy cornea, fixed dilation of affected pupil

Mx - pilocarpine eye drops, acezolamide

Question 3

Diabetic retinopathy

Answer 3

*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

Question 4

Central retinal artery stenosis

Answer 4

*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

Question 5

Anteroir uveitis

Answer 5

• 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, pain, small and irregular pupil, photophobia, blurred vision, red eye

Mx - Urgent review to ophthalmology
- Atropine drops to dilate pupils and relive pain
- steroid drops

Question 6

Normal fundoscopy

Answer 6

• cup ratio - <0.6 - glaucoma increases
• colour - bright orange
• clear margins - blurring shows swollen optic nerve
  *quadrants - Superior and inferior nasal and temporal

Question 7

Optic neuritis

Answer 7

• Painful loss of vision in 1 eye (gradual)

Cx - inflammation of optic nerve, causing papillodema

Mx - timolol to reduce pressure
- acteazolamide
- thrombolytics if clot

Question 8

Central retinal venous occlusion

Answer 8

• Less sudden painless loss of vision

Cx - blockage

Sx/Ix - redness, tortuous vessels, cotton wool spots, papillodema, blurry vision

Mx - Anti VEGF

Question 9

Retinal detachment

Answer 9

• Flashing lights worse open eye movements in temporal area
• curtain coming down

Cx - poor diabetes, high BP, trauma

Mx - surgery - pneumatic retinopexy
- vitrectomy

Question 10

Macular degeneration

Answer 10

• Age related reduction in visual acuity

Ix - presence of drusen, and yellow pigmentation

Mx - Vitamin supplements