Spasmus nutans (Q89406)

It is a rare and benign eye movement disorder which starts in the first year of life. It consists of high frequency, small amplitude, intermittent, horizontal pendular eye movements. It is often accompanied by head nodding, especially when the child is fixating at objects. It almost always spontaneously disappears by the 3rd year of life. Rarely optic chiasma tumors may be the cause.