Person is not able look down. Which extra ocular muscle is affected:
Ans. (a) Superior obliqueRef: A.K. Khurana 6th ed. / 337-39* The function of superior oblique is quite contrary to its name. Its action is depression of eyeball, which helps to see down.* Its yoke muscle is inferior rectus, which also has the similar function as superior oblique.* There are 9 Gaze:# Primary : Straight# Secondary: Up, down, left, right# Tertiary: Up left, Up, right, Down left, Down right* ACTIONS OF EOMMuscleFunction PrimarySecondaryTertiaryLateral rectusAbduction--Medial RectusAdduction--Inferior RectusDepressionExtortionAdductionSuperior rectusElevationIntortionAdductionInferior ObliqueExtortionElevationAbductionSuperior obliqueIntortionDepressionAbduction* Mnemonics: SinRad (all superior muscles causes Intortion; all rectus muscles causes Adduction EXCEPT Lateral rectus)
Superior oblique
Inferior oblique
Superior rectus
Lateral rectus
Ocular Motility