Retinal occlusion Flashcards
central retinal artery and vein occlusion, retinal detachment, diabetic retinopathy, retinitis pigmentosa (17 cards)
What is the most common cause of central retinal artery occlusion?
Atherosclerosis is the most common cause, but it can also be caused by giant cell arteritis, which reduces blood flow to the ophthalmic or central retinal artery
How does central retinal artery occlusion typically present?
- sudden, painless unilateral visual loss
- relative afferent pupillary defect
- fundoscopy: ‘cherry red’ spot on a pale retina
What is the significance of the “cherry red spot” seen on fundoscopy in central retinal artery occlusion?
The cherry red spot is seen at the fovea, which is thinner and reveals the red-colored choroid beneath, contrasting with the pale retina due to lack of perfusion.
What are the key differential diagnoses for sudden painless vision loss?
- Retinal detachment
- central retinal artery occlusion
- central retinal vein occlusion
- vitreous hemorrhage (e.g., diabetic retinopathy)
- amaurosis fugax
How should central retinal artery occlusion be managed?
- vision-threatening emergency, requiring immediate referral for stroke
- any underlying conditions should be identified and treated (e.g. IV steroids for GCA)
What causes retinal vein occlusion?
Retinal vein occlusion occurs when a blood clot (thrombus) forms in the central retinal vein (CRVO) or one of its branches (BRVO), blocking the drainage of blood from the retina
What are the risk factors for retinal vein occlusion?
- age >65 years
- Hypertension,
- cardiovascular disease
- diabetes
- hyperlipidaemia
- glaucoma
- smoking,
What symptoms are typically seen in retinal vein occlusion?
sudden, painless blurred vision or vision loss
* BRVO: vision loss corresponds to the affected area
* if the macula is involved, central vision is lost.
What characteristic findings are seen on fundoscopy in retinal vein occlusion?
- Dilated tortuous retinal veins
- retinal haemorrhages
- retinal oedema
How is retinal vein occlusion managed?
- Immediate referral to an ophthalmologist
- management of RFs
Indications for treatment in patients with CRVO include: - macular oedema - intravitreal anti-vascular endothelial growth factor (VEGF) agents
- retinal neovascularization - laser photocoagulation
What is retinal detachment and why is it significant?
- Retinal detachment occurs when the neurosensory tissue of the retina separates from the underlying pigment epithelium
- It’s a reversible cause of visual loss if treated before the macula is affected
- Left untreated, it leads to permanent vision loss.
What are the key risk factors for retinal detachment?
- Diabetic retinopathy
- myopia
- increasing age
- posterior vitreous detachment
- previous cataract surgery
- eye trauma (e.g., boxing),
What symptoms should raise suspicion of retinal detachment?
- New onset floaters or flashes
- sudden painless visual field loss described as a curtain or shadow progressing towards the center
- If the macula is involved, central vision loss can worsen, and peripheral vision may be reduced.
What sign can be detected on the swinging light test in retinal detachment?
A relative afferent pupillary defect, particularly if the optic nerve is involved
What findings are typically observed on fundoscopy in retinal detachment?
- red reflex is lost
- retinal folds may appear as pale, opaque, or wrinkled forms
- Small breaks may appear normal.
How should suspected retinal detachment be investigated
urgent referral <24 hours) for slit-lamp examination and indirect ophthalmoscopy to assess for pigment cells and vitreous haemorrhage.
How should patients with suspected retinal detachment be managed?
- retinal tears: Laser therapy or Cryotherapy
- detachment: vitrectomy, scleral buckle or pneumatic retinopexy
