Pachygyria Thick pachygyria 2019-09-03T12:56:36Z Pachygyria with cortical thickness above 10 mm Pachygyria with cortical thickness > 10 mm Pachygyria with a very thick cerebral cortex measuring 10-20 mm. Note that cortical thickness cannot be measured reliably on scans done between 3 and 24 months of age.