What is Neuronal Migration Disorders?

These types of disorder (NMDs) are a group of birth defects caused by the abnormal migration of neurons in the developing brain and nervous system. In the developing brain, neurons must migrate from the areas where they are born to the areas where they will settle into their proper neural circuits.

Causes of Neuronal Migration Disorders:

Neuronal Migration Disorders may be caused by genetic or biochemical abnormalities. Several genetic abnormalities have been identified, including a deletion of a gene on chromosome which causes lissencephaly and a mutation of a gene on chromosome, which causes lissencephaly in males and band heterotopia in females.

Symptoms of Neuronal Migration Disorders:

The symptoms of this disorder may include hypotonia (reduced muscle tone), seizures, developmental delay, mental retardation, growth failure, feeding difficulties, microcephaly, and motor dysfunction. Most children with an NMD appear normal, but some disorders have characteristic facial or skull features that can be recognized by a neurologist.

Diagnosis of Neuronal Migration Disorders:

The most usually diagnosis made by neuroimaging. CT-Scan or MRI of the brain will show the characteristic abnormality. MRI has better resolution and may detect polymicrogyria or small heterotopias more easily than CT-Scan. Genetic testing is available for patients with lissencephaly to identify whether the genes are defective.

Treatment of Neuronal Migration Disorders:

As yet, no known treatment for the various neuronal migration disorders at this time. But several symptomatic treatment may include anti-seizure medication and special or supplemental education consisting of physical, occupational, and speech therapies.