Cephalic Disorders

Home » Cephalic Disorders » Megalencephaly, Microcephaly, Porencephaly

Megalencephaly

This condition is marked by an abnormally large, heavy, usually malfunctioning brain. The head may be enlarged at birth or become abnormally large in the early years. A rare variation on this condition, unilateral megalencephaly (also called hemimegalencephaly), involves enlargement of half of the brain. This results in a large, often asymmetrical head.

Causes
Megalencephaly may be caused by a disturbance in the process that controls the way nerve cells divide to form new cells (called nerve cell proliferation). Males are more likely to be afflicted than females.

Signs and Symptoms
Symptoms may include delayed development, convulsions, seizures, and brain cortex/spinal cord dysfunction. Unilateral megalencephaly usually results in mental retardation and severe seizures.

Treatment
Treatment is symptomatic.

Prognosis
Prognosis varies according to the severity of associated disorders. Prognosis for those afflicted with unilateral megalencephaly is poor.

Microcephaly

In microcephaly, the circumference of the head is markedly smaller than normal for the infant's age and sex. Microcephaly can be congenital or can develop during the first years of life.

Causes
The condition may be caused by factors related to abnormal brain growth or from chromosomal abnormalities.

Signs and Symptoms
At birth, the head of a microcephalic infant may be either normal or abnormally small. In many cases the head fails to grow as the face develops at a normal rate, resulting in the development of a small head with a large face, receding forehead, and scalp with loose, wrinkled, skin. The smallness of the skull becomes increasingly evident with age. The child's entire body may be underweight and dwarf-like. Motor functions often are poor, ranging from simple clumsiness to spastic quadriplegia (affecting all four limbs). Speech development often is subnormal. The child may suffer convulsions and be hyperactive or mentally retarded.

Treatment
Treatment for microcephaly is symptomatic and supportive.

Prognosis
Prognosis varies according to the severity of the child's associated abnormalities. Life expectancy usually is short.

Porencephaly

In porencephaly a cyst or cavity develops in a cerebral hemisphere. The disorder can occur before or after birth.

Causes
Porencephaly may have a number of different causes, including absence of brain development and lesions that destroy brain tissue.

Signs and Symptoms
Symptoms include delayed growth and development, slight or partial paralysis, decreased muscle tone (hypotonia), seizures or spasms, macrocephaly or microcephaly, epilepsy, hydrocephalus, shrinkage or shortening of muscles, and mental retardation. Speech development may range from poor to absent.

Diagnosis
Porencephalic cysts are sometimes detected in infancy. Severely affected infants usually display symptoms shortly after birth, and diagnosis usually is confirmed before age 1 by transillumination (passing light through) of the skull, CT scan, MRI scan, or ultrasonography.

Treatment
Treatment may include physical therapy, medication for seizures, and a shunt for hydrocephalus.

Prognosis
The location and extent of the brain damage determines the prognosis. Some patients develop normal intelligence and experience only minor neurological problems; others may be severely disabled. Many die before age 10.

© 1998-2008 Healthcommunities.com, Inc. All Rights Reserved.

Cephalic Disorders Resources

	Join Our Cephalic Disorders Forum Do you have a question, want to share medical advice, or just need to discuss your situation with someone else having a similar experience? The healthchannels forum is a resource for everyone to share and discuss their health and medical needs with others.	Advertising Disclaimer
	Living with...Share your story Do you have a personal health story that you would like to share with others? As a source of free patient education, our goal is to provide our users with trustworthy information and support from others. That's why we've started our "Living with..." sections.
	Our "Living With..." support pages are a place to share experiences about living with a certain condition, disease, disorder, or illness and for loved ones of those dealing with health-related issues. Many people, especially when newly diagnosed, find comfort in knowing that others are having a similar experience. Help others by sharing your story. View stories already submitted.
	Stay Updated Sign up for our newsletter and receive important updates on the medical conditions that are most important to you.
Advertising Disclaimer To quickly access health information from your website's browser, download Healthcommunities.com's healthchannels toolbar.