underneath a computerized tomography (ct scan) scan, these both appear similar in that the cerebral cortex appears thickened. however, mri with a t1 weighted inversion recovery will illustrate the gray-white junction that is characterized by patients with pmg. an mri is also usually preferred over the ct scan because it has sub-millimeter resolution. the resolution displays the multiple folds within the cortical area, which is continuous with the neuropathology of an infected patient. neuropathological techniques gross examination exposes a pattern of many small gyri clumped together, which causes an irregularity in the brain surface. the cerebral cortex, which in normal patients is six cell layers thick, is also thinned. as mentioned prior, the mri of an affected patient shows what appears to be a thickening of the cerebral cortex because of the tiny folds that aggregate causing a more dense appearance. however, gross analysis shows that an affected patient can have as few as one to all six of these layers missing. treatment the pmg malformation cannot be reversed, but the symptoms can be treated. the removal of affected areas through hemispherectomy has been used in some cases to reduce the amount a seizure activity. few patients are candidates for surgery. the global developmental delay that affects 94% can also be mitigated in some patients with occupational, physical, and speech therapies. the important aspect to realize is pmg affects each patient differently and treatment options and mitigation techniques will vary. many services are available to help, most children's hospitals can direct caregivers guidance where to get the information they need to seek assistance. epidemiology the incidences of pmg and its different forms are unknown. however, the frequency of cortical dysplasia in general has been estimated to be 1 in 2,500 newborns. pmg is one of the best-known and most common malformations of cortical development, accounting for 20% of all cases. in the largest series of pmg cases, the bilateral perisylvian pattern was the most common topological pattern (52% of cases) followed by the unilateral perisylvian pattern (9% of cases). history limited information was known about cerebral disorders until the development of modern technologies. brain imaging and genetic sequencing greatly increased the information known about polymicrogyria within the past decade. understanding about development, classification and localization of the disorder have greatly improved. for instance, localization of specific cortex regions affected by the disease was determined. this allowed for clinical symptoms of patients to be linked with localized cortex areas affected. a gene that was identified to be a contributor to bilateral frontoparietal polymicrogyria was gpr56.