1 post tagged “what is megalencephaly”

Megalencephaly, also called macrencephaly, is a condition in which an infant or child has an abnormally large, heavy, and usually malfunctioning brain. By definition, the brain weight is greater than average for the age and gender of the child.  Head enlargement may be evident at birth or the head may become abnormally large in the early years of life. Megalencephaly is thought to be related to a disturbance in the regulation of cell production in the brain.  In normal development, neuron proliferation - the process in which nerve cells divide to form new generations of cells - is regulated so that the correct number of cells is produced in the proper place at the appropriate time.

Symptoms of megalencephaly include delayed development, seizures,   and corticospinal (brain cortex and spinal cord) dysfunction.  Megalencephaly affects males more often than females. Unilateral megalencephaly or hemimegalencephaly is a rare condition that is characterized by the enlargement of one side of the brain. Children with this disorder may have a large, asymmetrical head accompanied by seizures, partial paralysis, and mental retardation. Megalencephaly is different from macrocephaly (also called megacephaly or megalocephaly), which describes a big head, and which doesn’t necessarily indicate abnormality.  Large head size is passed down through the generations in some families. 

Unilateral megalencephaly or hemimegalencephaly is a rare condition characterized by the enlargement of one-half of the brain. Children with this disorder may have a large, sometimes asymmetrical head. Often they suffer from intractable seizures and mental retardation. The prognosis for those with hemimegalencephaly is poor.

Megalencephaly is thought to be related to a disturbance in the regulation of cell reproduction or proliferation. In normal development, neuron proliferation - the process in which nerve cells divide to form new generations of cells - is regulated so that the correct number of cells is formed in the proper place at the appropriate time. Symptoms of megalencephaly may include delayed development, convulsive disorders, corticospinal (brain cortex and spinal cord) dysfunction, and seizures. Megalencephaly affects males more often than females. Unilateral megalencephaly or hemimegalencephaly is a rare condition and is characterized by the enlargement of one-half of the brain.

Megalencephaly affects males more often than females. Unilateral megalencephaly or hemimegalencephaly is a rare condition and is characterized by the enlargement of one-half of the brain. Children with this disorder may have a large, sometimes asymmetrical head. Often they suffer from intractable seizures and mental retardation.

This disorder can present as a seperate disease or syndrome while other times it may be a component of another syndrome (e.g. neurofibramatosis I or von Recklinghausen Disease). This variation of megalencephaly can also be inherited as an autosomal dominant disorder. If you wish your child (I assume this is what the question is in relation to) to be evaluated for reassurance purposes, I would recommend you make an appointment at the CCF Department of Pediatric Neurology or a pediatric neurologists recommended by your family pediatrician.

There is no standard treatment for megalencephaly. Treatment will depend upon the disorder with which the megalencephaly is associated and will address individual symptoms and disabilities. The prognosis for individuals with megalencephaly largely depends on the underlying cause and the associated neurological disorders. The prognosis for those with hemimegalencephaly is poor.