Ophthalmology

Question 1

What muscle and nerve are responsible for closing of the eyelids?

Answer 1

orbicularis oculi innervated by the facial (seventh) cranial nerve.

NB. in a Bells palsy, the orbicularis oculi muscle may be weak, and the eyes may not close, potentially resulting in corneal exposure.

Question 2

What muscle and nerve are responsible for opening of the eyelids?

Answer 2

levator palpebrae superioris (LPS) muscle and Muller’s muscle.
LPS supplied by oculomotor (third) cranial nerve.

The accessory retractor, Muller’s muscle supplied by the sympathetic system.

Question 3

What are the CSF findings in Guillain Barre syndrome?

Answer 3

Normal white cell count with raised protein (albumino-cytologic dissociation)

Question 4

What blood tests can be ordered to investigate myasthenia gravis?

Answer 4

Serum acetylcholine receptor antibody, muscle-specific tyrosine kinase antibodies (if above negative/equivocal)