NEET PG DENTAL EXAM

Detailed explanation-1: -In each eye, the superior oblique muscle functions as the trochlea. The trochlear nerve innervates this muscle to lift the eyes so you can look down. The nerve also enables you to move your eyes toward your nose or away from it.

Detailed explanation-2: -Thus, a trochlear nerve palsy causes an ipsilateral higher eye (i.e., hypertropia) and excyclotorsion (the affected eye deviates upward and rotates outward). Patients may report vertical and/or torsional diplopia that is usually worse on downgaze and gaze away from the affected side.

Detailed explanation-3: -Fourth cranial nerve palsy may affect one or both eyes. Because the superior oblique muscle is paretic, the eyes do not adduct normally. Patients see double images, one above and slightly to the side of the other; thus, going down stairs, which requires looking down and inward, is difficult.