Which statement best describes the muscles of the eye?
Orbicularis oculi shuts the eyes when contracted. It is a muscle of facial expression and is, therefore, innervated by the facial nerve. The four rectii muscles arise from the tendinous ring around the optic foramen, and medial pa of the superior orbital fissure. Superior oblique arises superior and medial to the ring and inferior oblique arises from the floor of the orbit. All the extra-ocular muscles are innervated by the oculomotor nerve except the superior oblique(SO4 -trachlear nerve) and the lateral rectus.(LR6 -abducens nerve) Sphincter pupillae is innervated by parasympathetic fibres from the oculomotor(3rd) nerve. These fibres are carried by the sho ciliary nerves.(SP-P) Dilator pupillae is innervated by sympathetic fibres carried the long ciliary nerves.(branch of 5th nerve)(DP-S)
The superior and inferior obliques arise from the tendinous ring.
The superior oblique is innervated by the oculomotor nerve.
Sphincter pupillae is innervated by sympathetic nerves.
Closure of the eye is controlled by the facial nerve.
Eye, Nose and Ear