Porencephaly is characterized by a circumscribed intracerebral cavity of variable size that may be bordered by abnormal polymicrogyric grey matter. In extreme cases, this cavity may result in a communication between the pial surface and the ventricle; this is termed schizencephaly.
Prevalence is unknown.
The disease typically manifests in infants. The clinical manifestations of porencephaly depend on the location and the size of the lesion. Hemiplegic cerebral palsy is the commonest feature. Intellectual deficit and epilepsy are frequently reported. According to their topography, which usually corresponds to territories supplied by cerebral arteries, porencephaly (like schizencephaly and polymicrogyria) is thought to result from an ischemic injury, occurring mid-gestation.
A search for mutations leading to a hypercoagulable state is underway. Recently, mutations in the COL4A1 gene have been described in four of the already published families with porencephaly and in one new unrelated family.
Most cases are sporadic. However, some observations of familial recurrences have been reported, suggesting that genetic factors could be involved. Familial porencephaly is a very rare condition usually transmitted as an autosomal dominant trait with incomplete penetrance.
There is no specific treatment available for porencephaly. Symptomatic treatment includes physical therapy, anti-epileptic drugs if epilepsy is present, and shunting procedures for treatment of hydrocephaly.
Last update: April 2006
- Pr Patrick VAN BOGAERT
- Dr Nicole VAN REGEMORTER