Brain abnormalities in tuberous sclerosis complex.

Tuberous sclerosis complex is an autosomal dominant multisystem disorder. Spontaneous mutations occur in up to 60% of patients with gene loci located on chromosomes 9q34 (TSC1) and 16p13 (TSC2). Diagnosis is established with the identification of various neurocutaneous markers and multiple organ system hamartomas. The variable expression of severity, the potential for cognitive dysfunction, and epilepsy compound the clinical picture. The intracranial abnormalities include the identification of migration and hamartomatous brain lesions, such as tubers, subependymal nodules, and subependymal giant cell astrocytomas. A number of other neuroimaging and morphometric abnormalities coexist, which can be identified with current neuroimaging techniques. This review examines the spectrum of brain abnormalities encountered in tuberous sclerosis complex and presents them as not merely a collection of lesions but more cohesively in the context of a global neuronal migration disorder.