Polymicrogyria – genetics, clinical and neuroimaging characteristics


  • D. Deneva UHATNP „St. Naum”
  • I. Aleksandrova UHATNP "St.Naum"; Medical university – Sofia
  • A. Asenova UHATNP "St.Naum"; Medical university – Sofia
  • N. Topalov UHATNP "St.Naum"; Medical university – Sofia
  • M. Koleva UHATNP „St. Naum”
  • E. Rodopska UHATNP „St. Naum”
  • E. Slavkova UHATNP „St. Naum”
  • V. Tomov UHATNP „St. Naum”
  • V. Bojinova UHATNP „St. Naum”


polymicrogyria, cortical malformations, magnetic resonance, еpilepsy


Malformations of cortical development are macroscopic and/or microscopic abnormalities of the cerebral cortex that arise as a result of a disruption of the normal stages of corticogenesis.
Polymicrogyria (PMG) is characterized by excessive number of abnormally small cerebral gyri, separated by shallow sulci, giving the cortical surface and cortical–white matter junction an irregular appearance. Increasing evidences suggest that PMG occurs as a consequence of impaired late neuronal migration. Polymicrogyria is one of the most common malformations of cortical development, associated with a variety of clinical manifestations, including epilepsy, cognitive and motor deficits, and speech disorders. The etiology of PMG is heterogeneous and includes both genetic and non-genetic causes. To date, more than 50 genes have been linked to PMG. MRI is the neuroimaging of choice to evaluate the details of PMG and associated structural abnormalities.
It is important to use optimal imaging techniques, including thin sections and age-specific protocols. Genetic counseling is beneficial for the affected children and their families. The efforts are focused on increasing the success rate of PMG diagnosis, thereby improving patients’ care and treatment.


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How to Cite

Deneva, D., Aleksandrova, I., Asenova, A., Topalov, N., Koleva, M., Rodopska, E., Slavkova, E., Tomov, V., & Bojinova, V. (2022). Polymicrogyria – genetics, clinical and neuroimaging characteristics. Bulgarian Neurology, 23(1), 18–23. Retrieved from http://www.nevrologiabg.com/journal/index.php/neurology/article/view/100