Brief Answer: Clinical features depends on extent of abnormality Detailed Answer: Hi, Thank you for your query on Healthcare Magic. Migrational neuronal abnormalities are a group of disorders in which there will be defective migration of neuronal cells to the various parts of brain during embryonic stage. Abnormal migration of neuronal cells leads to symptoms and signs depending on the extent of brain involvement, timing of neuronal insult during brain development, and a host of environmental and genetic factors. Clinically the child will present with failure to thrive, marked developmental delay, small head, seizures, mental retardation, motor paralysis, and optic atrophy. Severity of symptoms depends on extent of brain involvement, underlying genetic abnormality, and timing of insult. As your grandson has migrational abnormalities of the right hemisphere, the child will have involvement of the left side of his body predominantly. Hope I have answered your query, if you have any clarification please let me know. Regards.

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