Double vision Flashcards
What muscles does the occulomotor nerve supply (CN III)?
- Superior, inferior and medial rectus
- Inferior oblique
- Levator palpebrae superioris
What muscles does the trochelar nerve supply (CN IV)?
Superior Oblique
What muscles does the abducens nerve supply (CN VI)?
Lateral Rectus
What is binocular diplopia?
- The images produced by the two eyes do not match, so the images are misaligned relative to one another
- Diplopia disappears when one eye is covered
What is monocular diplopia?
- Affects one eye and continues when unaffected eye is covered
- Can be caused by abnormalities with the lens, cornea and retina, causing a splitting of the image
What causes SOP?
- Congenital palsy
- Head injuries
- Microvascular palsies
- Inflammation or direct pressure on the nerve
What are the characteristics of SOP?
- Tilt/turn head to one side
- Double vision when looking downwards
- Nasal upshoot
What causes LRP?
- Microvascular palsy
- Direct pressure on CN VI
- Head injuries
- Inflammation
What are the characteristics of LRP?
- Horizontal double vision
- Affected eye cannot abduct
What causes IIIRD nerve palsy?
- Microvascular palsy
- Direct pressure on IIIrd nerve
- Head injuries
- Ophthalmoplegic migraine
What is a red flag signs of IIIRD nerve palsy?
- Pain
- Anisocoria
Caused by direct pressure on nerve
Most common is an aneurysm on the posterior communicating artery in brain
What are the characteristics of IIIRD nerve palsy?
- Ptosis
- Eye deviated downwards and outwards
What is the management of microvascular palsies?
Most will resolve in 3-6 months
What are the characteristics of myasthenia gravis?
- Extraocular muscle weakness: diplopia
- Proximal muscle weakness: face, neck, limb girdle
- Ptosis
- Dysphagia
What is myasthenia gravis associated with?
- Thymomas
- AI disorders: pernicious anaemia, AI thyroid disorders, rheumatoid, SLE
- Thymic hyperplasia
