The Diagnosis of Band Heterotopia

Abstract

Patient 1: A 6-year-old girl was admitted with a 1 year history of atonic seizures (head drops). Her motor and mental development had been normal until age 5 years, but her family had noted behavioral changes about 2 months after the onset of seizures. Her past medical history was remarkable for febrile seizures. Physical and neurological examinations were unremarkable. Electroencephalography (EEG) demonstrated multifocal spike and wave paroxysms generalizing during sleep and bilateral widespread pseudo-periodic slowwave paroxysms with high amplitude (Fig 1). Atonic-myoclonic seizures were recorded. Brain magnetic resonance imaging (MRI) revealed no abnormalities but was performed under suboptimal conditions. Subacute sclerosing panencephalitis was first considered, but no cells or antimeasles antibodies were detected in cerebrospinal fluid. Further testing for metabolic disorders was unremarkable. Her repeat MRI revealed diffuse band heterotopia (Fig 2). Patient 2: A 7-year-old girl was admitted with atonicmyoclonic seizures manifested by dropping of the head, falling, jerking, and dropping objects. Motor and mental development had been normal until the seizure onset at the age of 4 years, but subsequently her family noted behavioral changes. Her EEG findings included spike and wave paroxsyms propagating from both occipital regions, bilateral pseudo-periodic slowwave and sharp wave discharges, and atonic seizures. Subtle MRI changes suggested band heterotopia, and bilateral band heterotopia was confirmed on her second MRI.