Brain imaging
In LIS1/PAFAH1B1-related lissencephaly, the cerebral convolutions are absent or abnormally broad and the cerebral cortex is abnormally thick.
In LIS1/PAFAH1B1-related subcortical band heterotopia (SBH), there are bilateral bands of grey matter interposed in the white matter.
Clinical features
Children with the most common types of LIS1/PAFAH1B1-related lissencephaly typically appear normal as newborns. Most affected children come to medical attention during the first year of life due to neurological deficits in the first weeks or months. The major medical problems are ongoing feeding problems and epilepsy of many different types that is often intractable.
Patients with severe LIS have early developmental delay, early hypotonia, later spastic quadriplegia, severe epilepsy and eventual profound intellectual disability.
Patients with LIS1/PAFAH1B1-related SBH have normal facial appearance, epilepsy, and intellectual disability.
Miller–Dieker syndrome (MDS) is characterised by severe lissencephaly, typical facial appearance and other birth defects (e.g., heart malformations).