Cortical malformation disorders

What are cortical malformations?

A cortical malformation (also called a migration disorder) is an abnormal shape or anatomy of the brain that is visible on an MRI scan. Known malformations include: lissencephaly, pachygyria, double cortex, heterotopias, schizencephaly and polymicrogyria.

Depending on the severity and location, they can cause different types of complaints, such as developmental delay, intellectual disability, epilepsy and motor and balance problems. These can be very serious symptoms, but sometimes the symptoms are so subtle that the disorder is only discovered by chance.

What causes cortical malformations?

Before birth, the brain grows rapidly so that at birth a child already has almost all the brain cells needed. During the growth of the brain there are three overlapping phases. The first phase is the proliferation phase; here the progenitor cells divide rapidly so that billions of brain cells are formed. The second phase is the migration phase; the newly created brain cells can no longer divide, but set off for their definitive place in the brain. For this, the brain cells move cells to the surface of the brain, guided by other cells and by substances that other cells secrete. The third phase is the organization phase; the brain cells settle into place and make connections with their environment.

When there is a disturbance in this brain development, for example because an error (mutation) has arisen in one of the genes needed for brain development, an abnormal shape or anatomy of the brain may develop; a malformation. We are investigating this at the clinic. The cause does not have to be genetic. An event during pregnancy that disrupts the brain development process can also result in a migration disorder. Such an event could, for example, be an infection or a reduced blood flow. This is sometimes difficult to prove afterwards.

How common are cortical malformations?

Most cortical malformations are very rare. Polymicrogyria is the most common. It is not known exactly how often.

Examination and diagnosis

At the Neurogenetics / Migration Disorders outpatient clinic, children are seen by the clinical geneticist and pediatric neurologist. They undergo a genetic and neurological examination with, if necessary, an MRI scan and / or additional examination (EEG). The genetic research is carried out by means of a DNA test. We discuss the findings of the MRI scan of the brain and the expectations for the future. Then we discuss the options for performing additional diagnostics into the underlying cause.

The Neurogenetics/migration disorder consultation hour

The consultation takes place on Mondays. Children can be referred by a pediatrician, neurologist or general practitioner. During the consultation, your child will be seen by our pediatric neurologist and clinical geneticist. We map the medical history of the child and the family and the child is physically examined. If necessary, a plan is discussed for additional diagnostics. It may happen that blood or other material is taken from the child for examination on the day of the visit. Follow-up appointments are made on the basis of the agreed diagnosis and follow-up, usually once a year.

The structure of the brain cannot be changed. We work with parents on the best possible conditions for children to develop. Treatment of epilepsy or other symptoms and child rehabilitation can play a role in this. If a genetic cause is identified, the clinical geneticist will discuss whether it could affect family members or subsequent pregnancies.

Clinical Genetics and Coordinator: Dr. Grazia Mancini
Pediatric neurology: Dr. Marie-Claire de Wit, Dr. Evita Medici-van den Herik

Click here  to go to the contact form or mail yourself to:

In order to provide the best possible care to patients with a rare condition, it is essential that global knowledge about the condition is gathered. Nationwide, centers of expertise have been set up to stimulate care for rare disorders and to gather knowledge. For the formal recognition of an expertise center by the Ministry of Health, an important condition is that the expertise center gathers, analyzes and shares knowledge through publications. These can be publications in scientific journals, but also treatment guidelines for health care professionals or information brochures for patients or caregivers. We optimize care and research within ENCORE through standardized follow-up and close collaboration between doctors and researchers. That way, we can ultimately develop better treatments for rare conditions. You may therefore be asked to participate in research. Participation in research is always on a voluntary basis. The data obtained is stored and analyzed in an anonymous form. All research has been approved in advance by an ethics review committee.

To learn more about Cortical Malformation Research at ENCORE, clicking here

Patient organization

There is no Dutch patient association. For people with heterotopias based on a mutation in the FLNA gene, there is an organization set up by a Canadian mother, clicking here to go to the website. Many parents also find each other through private Facebook groups.

There is a facebook group for lissencephaly, clicking here here to go to the Facebook page.

There is an association abroad for Polymicrogyria, clicking here to go to the website.


Click here for more information on the pediatric neurology website
Click here for more information on the website of the brain foundation