The trochlear nerve, also known as cranial nerve 4 (CN IV), controls the superior oblique muscle in your eye. This muscle allows you to move your eyeball down and shift your gaze from side to side.

The superior oblique muscle allows the eye to be turned downward and inward. When the fourth cranial nerve is injured or diseased, it can cause paralysis of the superior oblique muscle.

Congenital SOP (superior oblique paresis) and congenital Brown syndrome may be the same condition. The superior oblique muscle is underdeveloped and the trochlear nerve is missing in both ...

Thus, if the inferior oblique muscles are overacting and/or the superior oblique muscles are underacting, one would expect a relative convergence in downgaze and divergence in upgaze, resulting in ...

Unilateral inferior oblique muscle myectomy and recession in the treatment of inferior oblique muscle overaction: a longitudinal study. Eye 2003; 17: 1013–1018. Article CAS Google Scholar ...

She underwent a standard recession of the right inferior oblique muscle for a presumed right superior oblique palsy. Following surgery, her family noted that the left eye was now drifting upward.