Trastornos de migración neuronal

Neuronal migration disorders (NMDs) are a group of birth defects caused by the abnormal migration of neurons (nerve cells) in the developing brain and nervous system. Types of NMDs include:

• Agenesis of the corpus callosum: The tissue connecting the left and right sides of the brain is partially or completely missing.
• Agenesis of the cranial nerves: The nerves that lead from the brain to various parts of the head, neck, and trunk are partially or completely missing. 
• Argyria/lissencephaly: Absent or abnormally broad gyri in the cerebral hemispheres. Also known as lissencephaly, or “smooth brain.”
• Microgyria: The occurrence of abnormally small folds of the brain.
• Neuronal heterotopias (including band heterotopia): Gray matter appears in abnormal places in the brain, including around ventricles, in areas of white matter, or the fluid-filled spaces of the brain.
• Polymicrogyria: An abnormal number of small brain folds.
• Porencephaly: An abnormal fluid-filled cyst.
• Schizencephaly: A cleft or slit in the brain.

Neuronal migration disorders are genetic defects that are typically passed on from parent to child, though they also occur sporadically. Neuronal precursor cells change direction from a typical migration mode as they move from the ventricles into the cortex. This results in malformations of the cerebral hemispheres.

These disorders result from genetic defects passed from parent to child. Prenatal exposure to environmental stress and inflammation, as well as use of alcohol and drugs.

Neuronal migration disorders (NMDs) can be diagnosed using a prenatal ultrasound. Further detection is possible by running a fetal magnetic resonance imaging (MRI) scan. The latter can help provide more details on how severe the malformations are.

Some disorders have characteristic facial or skull features that can be recognized by a neurologist. Several genetic abnormalities in children with neuronal migration disorders (NMDs) have been identified, but the role they play in the development of these disorders is not yet well understood.

Symptoms vary, but often include:

• Poor muscle tone and motor function
• Convulsiones
• Retraso en el desarrollo
• Impaired cognitive development
• Failure to grow and thrive
• Difficulties with feeding
• Swelling in the extremities
• A small head

Diagnosis of neuronal migration disorders can be determined through an MRI scan, with further information available through an EEG (which measures any present seizure activity) or muscle tone measurements using an EMG.

Treatment is symptomatic and may include antiseizure medication and special or supplemental education consisting of physical, occupational and speech therapies.

Daily life of those diagnosed with NMDs typically involves taking prescribed medication (usually an anti-seizure medicine). Additionally, working with a team of physical, occupational and speech therapists can help with symptoms.

Para comprender mejor su diagnóstico y contribuir a una investigación de vanguardia, considere la posibilidad de participar en un ensayo clínico para que médicos y científicos puedan aprender más sobre las causas, los síntomas, el tratamiento y la prevención de esta enfermedad. La investigación clínica utiliza voluntarios humanos para ayudar a los investigadores a aprender más sobre un trastorno y, tal vez, a encontrar mejores formas de detectar, tratar o prevenir enfermedades de manera segura.

Se necesitan voluntarios (tanto sanos o con alguna afección o enfermedad), de todas las edades, sexos, razas y etnias para garantizar que los resultados del ensayo sean relevantes para la mayor cantidad posible de personas, y que los tratamientos sean seguros y eficaces para todo aquel que los necesite.

Para obtener información sobre cómo participar en investigaciones clínicas, visite NIH Clinical Research Trials and You. Más sobre ensayos clínicos que actualmente buscan participantes en Clinicaltrials.gov.