Extraocular Muscles Quiz

Which of the following extraocular muscles is responsible for abducting, elevating, and extorting the eye?

• Superior rectus

• Inferior rectus

• Inferior oblique

• Superior oblique

The lateral rectus muscle is innervated by which cranial nerve?

• Cranial nerve III

• Cranial nerve IV

• Cranial nerve V

• Cranial nerve VI

A patient presents with an inability to elevate their upper eyelid. Which muscle is likely affected?

• Levator palpebrae superioris

• Superior oblique

• Superior rectus

• Inferior oblique

A lesion in cranial nerve IV would likely affect which of the following actions?

• Abducting the eye

• Medial rotation of the eye

• Lateral rotation of the eye

• Elevation of the upper eyelid

The mnemonic SO4 LR6 helps medical students remember the innervation of which two muscles?

• Superior rectus and lateral rectus

• Superior oblique and inferior oblique

• Superior oblique and lateral rectus

• Inferior rectus and superior rectus

The function of the ciliary muscle includes which of the following?

• Controlling the constriction of the pupil

• Elevating the upper eyelid

• Facilitating accommodation for near vision

• Medial rotation of the eye

Pupil constriction, or miosis, is controlled by which muscle and nervous system component?

• Dilator pupillae, sympathetic nervous system

• Sphincter pupillae, parasympathetic nervous system

• Sphincter pupillae, sympathetic nervous system

• Dilator pupillae, parasympathetic nervous system

A patient is unable to look down and medially. Which muscle is most likely affected?

• Inferior oblique

• Superior rectus

• Superior oblique

• Inferior rectus

Which of the following muscles is directly involved in pupil dilation (mydriasis)?

• Sphincter pupillae

• Dilator pupillae

• Inferior oblique

• Ciliary muscle

The superior orbital fissure transmits all of the following nerves except:

• Cranial nerve III

• Cranial nerve IV

• Cranial nerve VII

• Cranial nerve VI