Slow tremor and macrocephaly: expanded version of the bobble-head doll syndrome.

The clinical features of three children in whom a slow tremor involving the head, trunk, or limbs was associated with macrocephaly are presented. The findings were similar but not identical to those previously reported in four children with the bobble-head doll syndrome. These seven children have many of the signs and symptoms found in patients with surgically or spontaneously arrested hydrocephalus, including motor incoordination, behavior and psychologic deviations, and endocrine dysfunction. The tremor which can be voluntarily inhibited and which disappears following shunt surgery, is unique. The theoretical basis for the tremor is briefly discussed.