Head bobbing in a patient with a cyst of the third ventricle.

The case of a 7 year-old boy with 'bobble head doll syndrome' associated with a cyst in the third ventricle is reported. This movement disorder appears in early childhood and consists mostly in a rhythmic to-and-fro bobbing of the head and eventually of the trunk. As in three previously described cases, this case showed only slight decrease of the 'tic' after partial removal of the cyst by transcortical exploration of the third ventricle. In an inquiry and a survey of the literature, 17 cases with bobble head doll syndrome were collected. The average age of the described cases was 7 years at time of diagnosis. In 13 cases a slow-growing cyst or mass in the anterior part of the third ventricle of close to this region was found. There was no case observed with an acute lesion, in 3 cases it was thought an aqueduct stenosis should be the cause, and in 1 case the cause was unknown.