In conjugate gaze palsies, the two eyes cannot move in one direction (side to side, up, or down) at the same time.
Conjugate gaze palsies affect horizontal gaze (looking to the side) most often. Upward gaze is affected less often, and downward gaze is affected even less often. People may notice that they cannot look in certain directions.
There are no specific treatments.
Horizontal gaze palsy:
The most common cause is damage to the brain stem, often by a stroke. Often, the palsy is severe. That is, moving the eyes past the midline to the opposite side is very difficult.
Palsies can also be caused by damage to the front part of the cerebrum, usually by a stroke. The resulting palsy may not be as severe as that caused by damage to the brain stem, and symptoms often lessen with time.
Vertical gaze palsy:
Vertical gaze decreases gradually with age, but vertical gaze palsy is more severe than age-related changes. Usually, upward gaze is affected. The most common cause is damage to the top part of the brain stem (midbrain), usually by a stroke or tumor.
Parinaud syndrome is an upward vertical gaze palsy. It usually results from a tumor or stroke. People with this syndrome tend to look down. Their eyelids are pulled back, and the pupils are dilated.
Downward gaze palsy:
If downward gaze but not upward gaze is impaired, the cause is usually progressive supranuclear palsy (see Progressive Supranuclear Palsy).
Last full review/revision October 2014 by Michael Rubin, MDCM