Cranial Nerves III IV VI

1. The Edinger–Westphal nucleus is functionally classified as:

Somatic efferent General visceral efferent Special visceral afferent General somatic afferent

2. Which extraocular muscle is NOT supplied by cranial nerve III?

Inferior oblique Superior rectus Lateral rectus Medial rectus

3. Trochlear nerve nucleus lies at the level of:

Superior colliculus Inferior colliculus Facial colliculus Pontomedullary junction

4. Which cranial nerve runs closest to the internal carotid artery in the cavernous sinus?

CN III CN IV CN V1 CN VI

5. Complete decussation of fibers occurs in:

Oculomotor nerve Trochlear nerve Abducens nerve Optic nerve

6. Which muscle causes intorsion of the eyeball?

Inferior oblique Superior rectus Superior oblique Lateral rectus

7. Abducens nerve nucleus is located:

Ventral pons Dorsal pons beneath facial colliculus Midbrain tegmentum Medulla oblongata

8. Which nerve enters the orbit outside the common tendinous ring?

CN III superior division CN III inferior division CN IV CN VI

9. Parasympathetic fibers to the eye synapse in:

Otic ganglion Pterygopalatine ganglion Ciliary ganglion Submandibular ganglion

10. Which muscle depresses the eye most effectively in adduction?

Inferior rectus Superior oblique Inferior oblique Medial rectus

11. A patient has ptosis, dilated pupil, and eye deviated down and out. The lesion is in:

Trochlear nerve Abducens nerve Oculomotor nerve Optic nerve

12. A patient complains of diplopia while walking downstairs. Which muscle is paralyzed?

Inferior rectus Superior oblique Lateral rectus Inferior oblique

13. Medial deviation of the eye at rest suggests damage to:

CN III CN IV CN VI CN II

14. Raised intracranial pressure most commonly affects which cranial nerve?

CN III CN IV CN VI CN VII

15. A lesion in the dorsal midbrain affecting a nerve that exits posteriorly will cause:

Loss of abduction Loss of adduction Loss of intorsion Loss of accommodation

16. A cavernous sinus thrombosis first affects lateral gaze. Which nerve is involved?

CN III CN IV CN V1 CN VI

17. Loss of pupillary light reflex with preserved eye movements suggests damage to:

Somatic fibers of CN III Parasympathetic fibers of CN III CN IV CN VI

18. Facial colliculus involvement will directly impair:

CN III nucleus CN IV nucleus CN VI nucleus CN V nucleus

19. A lesion of the inferior division of CN III will spare:

Medial rectus Inferior oblique Levator palpebrae superioris Inferior rectus

20. Which movement will be MOST affected in isolated superior oblique palsy?

Elevation in abduction Depression in adduction Abduction in primary gaze Adduction in elevation

Cranial Nerves III, IV & VI – Hard MCQs