Objective: Present a case of subcortical band heterotopia (SBH), a rare neuronal migration disorder subtype. Also known as “double cortex syndrome,” SBH refers to a distinct band of heterotopic gray matter separated just below the cortex by a layer of white matter. Clinically, SBH is most often associated with seizures, developmental delay, and intellectual disability. Subcortical band heterotopia is caused by a genetic mutation and primarily affects females. The patient is a 14-year-old male referred for evaluation secondary to cognitive issues and behavioral disturbance. Daily absence seizures were present with an onset of age 10 years. The patient was receiving significant academic support in a school for students with developmental disability. His history showed pronounced emotional dysregulation and subsequent outbursts resulting in peer relational and disciplinary problems. He had most recently struck a younger female peer in the head. Method: The patient's neuropsychological assessment covered intellectual functioning, academic skills, language, attention, executive functioning, learning and memory, visuospatial processing and perceptual integration, adaptive functioning, and social functioning. Results: Neuroimaging indicated extensive nonlissencephalic cortical dysplasia involving the parietal and occipital lobes with band heterotopia and polymicrogyria. Testing revealed markedly slow processing speed. Neurocognitive deficits were also noted in visually-mediated attention, executive functioning, and visuospatial processing and perceptual integration. With the exception of relatively intact intellectual functions, the patient's profile is consistent with the clinical course of SBH. Conclusion: The current case highlights the clinical utility of neuropsychology in the diagnosis and treatment of neuronal migration disorders.
Subcortical Band Heterotopia: An Adolescent Male Case
Arch Clin Neuropsychol (2015) 30 (6): 539-540.
25 August 2015