A case of infantile epileptic encephalopathy (Ohtahara syndrome) with EEG suppression-bursts at 2 days and associated with diffuse cerebral migrational and maturation disorder, diagnosed at autopsy at 19 months, is reported from Montreal Children’s Hospital, McGill University, Montreal, Canada. Seizures of multiple types, usually generalized tonic clonic, began on the first day and persisted until the child died, despite various AEDs, ACTH, and a failed trial of the ketogenic diet. CT at 2 days showed a parietal skull fracture and extradural hemorrhage. MRIs at 1 and 5 months showed delayed myelination, a thin corpus callosum, and increased CSF spaces. EEGs after 5 months of age recorded generalized epileptiform slow spike-and-wave and multifocal abnormalities. CSF exam revealed absence of GABA. Diagnosis of cerebral migration disorder was made only at autopsy by microscopic exam, showing microdysgenesis of cerebral cortex, hippocampal cell loss and astrogliosis, immature neurons, and enlarged dentate and olivary nuclei. 
COMMENT. Congenital or acquired structural malformations of cortical development are usually associated with Ohtahara syndrome. Evidence of cortical migration defect may be overlooked on MRI and may be uncovered only at autopsy by microscopic examination.