Background: Cyclic vomiting syndrome CVS is an episodic nausea and non- bilious vomiting disorder characterized by recurrent stereotypic symptoms with disease-free intervals. CVS in children is associated with a high prevalence of migraine, and is commonly considered a precursor to migraine . This study aimed to investigate the clinical manifestations of pediatric CVS and its prognosis, and to clarify its relationship with the risk of migraine development in children. Methods: The clinical features of children diagnosed with CVS before the age of 18 years at the designated hospital were retrospectively studied over the past 30 years 1976 - 2006 based on the Rome III or ICHD II criteria. Clinical evaluations, including age of onset, sex, family history, symptoms and duration during attacks, frequency, trigger events, electroencephalogram, treatment and subsequent development of migraine were assessed from chart records and telephone interviews. Results: Thirty-five children 17 males and 18 females were enrolled. Their age of onset ranged from 2 to 17 years mean, 6.8 +/- 3.1 years and frequency of attacks ranged from once to 36 times per year mean, 8.2 +/- 7.6 times. Duration of symptoms during each attack ranged from 1 to 45 days mean, 5.9 +/- 7.3 days. Of 20 children assessed for migraine development, seven subsequently developed typical migraine symptoms. There was younger onset age in the migraine-positive subgroup 5 +/- 1. 7 years than in the migraine-negative subgroup 8.9 +/- 3 years; p = 0.001. Co-morbid headache during CVS attack was also more evident in the migraine-positive subgroup 28.6% vs . 0%. Conclusion: Results of the study show that younger onset age and headache during CVS attacks may have increased risk of migraine development. Large-scale prospective studies are warranted to further clarify the relationship between CVS and migraine. ; 醫學系小兒科 ; 醫學系 ; 醫學院 ; 期刊論文