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CN IV Superior Oblique SO4 — FRCA Primary MCQ

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EasyAnatomyCN IV Superior Oblique SO4FRCA Primary

Regarding the anatomy of the eye the extraocular muscles are supplied by three cranial nerves. CN IV (trochlear) supplies:

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Correct answer: E — Superior oblique

CN IV supplies superior oblique only (SO4). CN VI supplies lateral rectus only (LR6). CN III supplies all remaining extraocular muscles: superior rectus / inferior rectus / medial rectus / inferior oblique / and levator palpebrae superioris. Mnemonic: LR6(SO4)3 = Lateral Rectus CN 6 / Superior Oblique CN 4 / all others CN 3.

Reference: RCoA 2021 Primary FRCA Curriculum