The most common lissencephaly observed, consisting of frontotemporal pachygyria and posterior agyria, is Grade 3.

Terms such as 'agyria' (no gyri) or 'pachygyria' (broad gyri) are used to describe the appearance of the surface of the brain.

Two characteristics of lissencephaly include its absence of convolutions (agyria) and decreased presence of convolutions (pachygyria).

One of the best known and most common types of neuronal migration disorders is lissencephaly, a diffuse cortical malformation relating directly to agyria and pachygyria.

This includes a spectrum of simplified cortex ranging from agyria (a total absence of cortical convolutions) to pachygyria (broadened gyri) with unusually thick cortex.

Sadlave - guitar (also in Notanga, ex-Burying Place, Fanarai, ex-Anubi, Agyria, Trolis & The Giberlingers, ex-Ruination)

Classical lissencephaly can range from agyria to regional pachygyria and is usually present along with subcortical band heterotopia (known as 'double cortex' to describe the circumferential bands of heterotopic neurons located beneath the cortex).

Type 1 lissencephaly is due to an error in migration.

Over 90% of children affected with lissencephaly have seizures.

The malformation is in fact characterized by lissencephaly (smooth brain).

Some children with lissencephaly will be able to roll-over, sit, reach for objects, and smile socially.

The prognosis for children with lissencephaly varies depending on the malformation.

In addition, type 1 lissencephaly is closely associated with cerebellar hypoplasia.

The severity of type I lissencephaly therefore varies with the mutation type.

LIS1 is responsible for the autosomal form of lissencephaly.

Total lack of reelin causes a form of lissencephaly.

The established classification scheme for lissencephaly is based on the severity (grades 1-6) and the gradient.

Genetic counseling is usually offered if there is a risk of lissencephaly, coupled with genetic testing.

It is associated with brain (lissencephaly, hydrocephalus, cerebellar malformations) and eye abnormalities.

Treatment for those with lissencephaly is symptomatic and depends on the severity and locations of the brain malformations.

In infants with classical lissencephaly, the head circumference may be smaller than would otherwise be expected (microcephaly).

Truncated (shortened) mutations of LIS1 tend to cause severe lissencephaly.

The imaging findings of this child's brain most likely represent diffuse pachygyria, a mild form of lissencephaly.

In lissencephaly, few or no sulci are seen on the cortical surface, resulting in a broad, smooth appearance to the entire brain.

The spectrum of lissencephaly is only now becoming more defined as neuroimaging and genetics has provided more insights into migration disorders.

Mutations of the LIS1 gene are associated with about 80% of those affected with lissencephaly.

Aristaless related homeobox, also known as ARX is a protein associated with mental retardation and lissencephaly.

Some types of lissencephaly are described below (OMIM numbers are included where available):

Type I lissencephaly, or agyria-pachygyria , is a rare developmental disorder characterized by the absence of gyri and sulci in the brain.

DCX was the first known gene causing X-linked lissencephaly and subcortical band heterotopia.

MDS is often called Miller-Dieker lissencephaly syndrome.

One of his early papers was his description of two siblings with lissencephaly, now known by the eponym Miller-Dieker syndrome.

The most common lissencephaly observed, consisting of frontotemporal pachygyria and posterior agyria, is Grade 3.

Terms such as 'agyria' (no gyri) or 'pachygyria' (broad gyri) are used to describe the appearance of the surface of the brain.

Two characteristics of lissencephaly include its absence of convolutions (agyria) and decreased presence of convolutions (pachygyria).

One of the best known and most common types of neuronal migration disorders is lissencephaly, a diffuse cortical malformation relating directly to agyria and pachygyria.

This includes a spectrum of simplified cortex ranging from agyria (a total absence of cortical convolutions) to pachygyria (broadened gyri) with unusually thick cortex.

Sadlave - guitar (also in Notanga, ex-Burying Place, Fanarai, ex-Anubi, Agyria, Trolis & The Giberlingers, ex-Ruination)

Classical lissencephaly can range from agyria to regional pachygyria and is usually present along with subcortical band heterotopia (known as 'double cortex' to describe the circumferential bands of heterotopic neurons located beneath the cortex).