Trochlear Nerve Palsy

A 56-year-old male complained of binocular vertical double vision for 1 month. He felt sudden dizziness and unsteady gait after working hardly. He denied headache or weakness of the limbs. Brain MRI was performed at local hospital and interpreted as lacunar stroke. After treatment, the dizziness recovered; however, the double vision persists. He felt comfortable when tilted his head to the left shoulder. He went for neuro-ophthalmologic consultation before a strabismus surgery.