Bobble-head doll syndrome in an infant with an arachnoid cyst: a case report

Bobble-head doll syndrome is a rare and unique movement disorder most commonly affecting children younger than 5 years of age. It is characterized by continuous or episodic movement at the frequency of 2-3 Hz. The exact mechanism of bobble-head doll syndrome has not been elucidated. Endoscopic ventriculocisternostomy is the optimal treatment option. In a literature review, there were less than 75 cases of bobble-head doll syndrome with suprasellar arachnoid cyst.

We report a case of a 1.5-year-old Asian-Syrian girl who presented with a history of excessive head nodding for 3 months that increased with walking, emotions, and stress; decreased during periods of concentration; and was absent during sleep. On physical examination, she was alert and normal, with no medical history. Laboratory assessment and ophthalmological examination were normal. Cranial magnetic resonance imaging demonstrated a well-defined thin-walled suprasellar arachnoid cyst measuring 3 × 5 × 7 cm that obstructed the foramina of Monro, with resulting hydrocephalus ventriculomegaly. The patient underwent endoscopic cystoventriculostomy and cystocisternostomy for the suprasellar arachnoid cyst. During the 6 months of follow-up, the head bobbing disappeared completely, and her growth was normal.

Despite the rareness of bobble-head doll syndrome, it is considered an important condition that must be investigated early to detect the cause and treated promptly to avoid potential complications.