Neuroimaging and clinical characterization of Sotos syndrome: Sotos syndrome is a well-known overgrowth syndrome characterized by excessive growth during childhood, macrocephaly, distinctive facial appearance and learning disability. This disorder is caused by mutations or deletions in NSD1 gene. The aim of this study is to examine the relationship between the neuroimaging and clinical features of children with Sotos syndrome. Six Turkish children with Sotos syndrome were followed up about 3-7 years. The diagnosis was confirmed with molecular genetic analysis. We identified the pathogenic NSD1 mutation including three novel in all patients. All the patients had a characteristic facial gestalt of Sotos syndrome consisting of triangular face with prominent forehead, frontoparietal sparseness of hair and small nose. However, the degree of psychomotor and intellectual development was variable. Severe learning defect and speech delay were remarkable in two patients. The neuroimaging analysis showed abnormalities in four of six patients including bilateral large ventricles, thinning of the corpus callosum and persistent cavum septum pellucidum et vergae. Typical craniofacial appearance is the primary finding for the diagnosis of the disease even in the infantile period. However, the degree of psychomotor and intellectual development is very variable and does not correlate with the neuroimaging findings.