Band heterotopia: Correlation of outcome with magnetic resonance imaging parameters

Abstract

The "band heterotopia" or "double cortex" is a brain anomaly that is presumed to result from a premature arrest of neuronal migration. Patients with this anomaly are reported to have a variable clinical course that has been, heretofore, unpredictable. The clinical records and magnetic resonance (MR) imaging studies of 27 patients with band heterotopia were retrospectively reviewed in an attempt to determine whether imaging findings are useful in predicting clinical outcome of affected patients. Statistical analyses revealed the following correlations: (1) severity of T2 prolongation in the brain with motor delay (p = 0.03); (2) degree of ventricular enlargement with the age of seizure onset (p = 0.04), and with development and intelligence (p = 0.04); (3) severity of pachygyria with the age of seizure onset (p = 0.01), seizure type (p = 0.03), and an abnormal neurologic examination (p = 0.002); (4) parietal involvement with delayed speech development (p = 0.05); (5) occipital involvement with age of seizure onset (p = 0.006); (6) age of seizure onset with development and intelligence (p = 0.03) and with an abnormal neurologic examination (p = 0.04); and (7) severity of the pachygyria and thickness of band with development of symptomatic generalized epilepsy (p = 0.002 and p = 0.02, respectively) and Lennox-Gastaut syndrome (p = 0.002 and p = 0.01, respectively).

Mutation analysis of the DCX gene and genotype/phenotype correlation in subcortical band heterotopia

“…Clinical severity has been observed to vary with band thickness. 24 Patients with thin partial frontal bands have the mildest phenotypes and may be asymptomatic. We therefore compared band location and thickness in different types of DCX mutations.…”

Ictal EEG Patterns in Band Heterotopia

“…In patients with BH, the severity of the associated epileptic syndrome and cognitive impairment often correlate with the degree of abnormal gyration in the outer cortical mantle (5,6,(8)(9)(10). In turn, the severity of gyral abnormality reflects, at least in part, the fraction of neuroblasts arrested during migration and composing the inner band of heterotopic grey matter (1,5,10).…”

“…BH can result in Lennox-Gastaut syndrome (3,5,10), and most often produces the clinical picture of a symptomatic generalized epilepsy. Although interictal EEG has been well characterized in many individuals with BH, ictal EEG findings are lacking.…”

Novel Mutation chrX:110644366 C>A of the DCX Gene in 4-year-old Girl with Sporadic Double Cortex Syndrome

“…[10][11][12] Infantile spasms and Lennox-Gastaut syndrome also have been reported. [14] About 60% of the patients have focal lobar or multifocal epileptic abnormalities, [10,11,14] but EEG findings are usually characterized by generalized slow spike-and-wave or polyspike and wave, and multifocal spiking. [11][12][13] In individuals with SBH, cognitive abilities range from normal to learning disabilities and/or severe intellectual disability.…”

“…The cerebral cortex in SBH may appear normal and/or thickened with or without simplified gyration. [14][15][16] DCX-related SBH is predominantly located in the frontoparietal lobe and is grade 6 (complete band heterotopia). Grade 5, a more severe malformation that overlaps with classic lissencephaly and band heterotopia, is characterized by SBH in the occipital regions and pachygyria in the frontal regions.…”