A hypertropia is seen in the right eye in primary gaze and becomes more pronounced when looking to the left and tilting the head to the right. Which EOM is most likely involved?

• A. Left Superior Oblique
• B. Right Inferior Oblique
• C. Left Inferior Rectus
• D. Right Superior Oblique

Answer: (D)

Focusing on how each eye and muscle move helps here: the superior oblique is the primary depressor of the eye when it is adducted (turned toward the nose) and it also intorts that eye. If the right superior oblique is weak, the right eye sits higher (hypertropic) even in neutral position. When looking to the left, the right eye must adduct and be depressed; with a weak right superior oblique, that depression fails and the vertical misalignment worsens. Tilting the head to the right further demands proper depressor/torsion on the right eye, so the hypertropia becomes more pronounced. This combination—right hypertropia that worsens with adduction (left gaze) and with head tilt to the right—is classic for a right superior oblique palsy.