Hemispheric polymicrogyria and neonatal seizures: a potentially life-threatening combination

Polymicrogyria (PMG) is a heterogeneous malformation of cortical development characterized by excessive gyration and abnormal cortical lamination. Typically, bilateral forms have more severe developmental delay and early-onset epilepsy, but the full spectrum of severity remains ill-defined. We report two cases of right hemispheric PMG and neonatal-onset, drug-resistant seizures culminating in early death. Case 1 began having seizures on Day 1 of life that intensified in severity and proved resistant to numerous antiepileptic drugs. He underwent right functional hemispherectomy but died three weeks post-operatively due to ongoing seizures. Case 2 presented with seizures on Day 3 of life and required respiratory support for prolonged ictal apnoeas. Seizures were resistant to antiepileptic drugs and eventually led to respiratory arrest, once aggressive resuscitative measures were withdrawn. In both cases, seizures seemingly originated independently in both hemispheres. These cases represent a severe phenotype of unilateral hemispheric PMG with bilateral seizures.