MRI findings in macrocephaly-cutis marmorata telangiectatica congenita.

We describe a child with macrocephaly-cutis marmorata telangiectatica congenita (M-CMTC), cherry red macules, megalencephaly with hemifacial and segmental overgrowth, macrosomia, and cutis marmorata telangiectasia congenita of the trunk, and visceral and subcutaneous cavernous hemangiomas. The megalencephaly is accompanied by MRI findings of CNS dysgenesis with protrusion of the cerebellar tonsils through the foramen magnum (Chiari I), lumbar syrinx, and hydrops of the optic nerves. The report of this additional patient further confirms the newly described macrocephaly-cutis marmorata telangiectatica congenita as a distinct clinical phenotype.