The megalencephaly-polymicrogyria-polydactyly-hydrocephalus (MPPH) syndrome is characterized by:
- Brain overgrowth o megalencephaly – often congenital
- Structural brain abnormalities such as polymicrogyria
- Hydrocephalus – may require neurosurgical intervention
- Extra digits (either fingers or toes)
Bilateral perisylvian polymicrogyria is characterized by:
- Epilepsy
- Oromotor weakness including dysphagia, difficulties handling oral secretions and expressive speech delay