Macrocephaly-capillary malformation (M-CM) is characterized by prenatal overgrowth, variable somatic and cerebral asymmetry, primary megalencephaly, characteristic facial features, an abnormal neurocognitive profile and cutaneous vascular malformations. It was previously known under the name macrocephaly-cutis marmorata telangiectatica congenital (M-CMTC). However a recent review of the previously reported cases has suggested that the vascular anomalies are not true CMTC but rather capillary malformations. The diagnosis is primary clinical and different criteria have been proposed for this purpose. However, M-CM is frequently associated with structural brain abnormalities that should be properly investigated and monitored because of their possible progressive development. We report the neuroradiological and morphological features observed in a girl with M-CM and we compared them with proposed diagnostic criteria found in the literature. (C) 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.