Hemorrhage occurring within the skull.

A deficiency or slowing down of growth pre- and postnatally.

Paralysis (complete loss of muscle function) in the arm, leg, and in some cases the face on one side of the body.

Polymicrogyria is a congenital malformation of the cerebral cortex characterized by abnormal cortical layering (lamination) and an excessive number of small gyri (folds).

Brunelli et al. (1996) described schizencephaly as an extremely rare congenital disorder characterized by a full-thickness cleft within the cerebral hemispheres. The clefts are lined with gray matter and most commonly involve the parasylvian regions (Wolpert and Barnes, 1992). Large portions of the cerebral hemispheres may be absent and replaced by cerebrospinal fluid. Two types of schizencephaly have been described, depending on the size of the area involved and the separation of the cleft lips (Wolpert and Barnes, 1992). Type I schizencephaly consists of a fused cleft. This fused pial-ependymal seam forms a furrow in the developing brain, and is lined by polymicrogyric gray matter. In type II schizencephaly, there is a large defect, a holohemispheric cleft in the cerebral cortex filled with fluid and lined by polymicrogyric gray matter. The clinical manifestations depend on the severity of the lesion. Patients with type I are often almost normal; they may have seizures and spasticity. In type II abnormalities, there is usually mental retardation, seizures, hypotonia, spasticity, inability to walk or speak, and blindness. Schizencephaly may be part of the larger phenotypic spectrum of holoprosencephaly (HPE; see 236100).

Spastic paralysis affecting all four limbs.

A bilateral tonic-clonic seizure is a seizure defined by a tonic (bilateral increased tone, lasting seconds to minutes) and then a clonic (bilateral sustained rhythmic jerking) phase.

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

A focal-onset seizure is a type of seizure originating within networks limited to one hemisphere. They may be discretely localized or more widely distributed, and may originate in subcortical structures.

An increase in size of the ventricular system of the brain.

A form of heterotopia were the mislocalized gray matter is located deep within the white matter.

A cavity within the cerebral hemisphere, filled with cerebrospinal fluid, that communicates directly with the ventricular system.

A form of strabismus with one or both eyes turned inward ('crossed') to a relatively severe degree, usually defined as 10 diopters or more.