Hydranencephaly is a rare condition in which the brain's cerebral hemispheres are absent and replaced by sacs filled with cerebrospinal fluid. An infant with hydranencephaly may appear normal at birth. The infant's head size and spontaneous reflexes such as sucking, swallowing, crying, and moving the arms and legs may all seem normal. However, after a few weeks the infant usually becomes irritable and has increased muscle tone. After a few months of life, seizures and hydrocephalus (excessive accumulation of cerebrospinal fluid in the brain) may develop. Other symptoms may include visual impairment, lack of growth, deafness, blindness, spastic quadriparesis (paralysis), and intellectual deficits. Hydranencephaly is considered to be an extreme form of porencephaly (a rare disorder characterized by a cyst or cavity in the cerebral hemispheres) and may be caused by vascular infections or traumatic disorders after the 12th week of pregnancy. Diagnosis may be delayed for several months because early behavior appears to be relatively normal. Some infants may have additional abnormalities at birth including seizures, myoclonus (spasm or twitching of a muscle or group of muscles), and respiratory problems.
March of Dimes Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 askus@marchofdimes.com http://www.marchofdimes.com Tel: 914-428-7100 888-MODIMES (663-4637) Fax: 914-428-8203 |
National Organization for Rare Disorders (NORD) P.O. Box 1968 (55 Kenosia Avenue) Danbury, CT 06813-1968 orphan@rarediseases.org http://www.rarediseases.org Tel: 203-744-0100 Voice Mail 800-999-NORD (6673) Fax: 203-798-2291 |
National Dissemination Center for Children with Disabilities U.S. Dept. of Education, Office of Special Education Programs P.O. Box 1492 Washington, DC 20013-1492 nichcy@aed.org http://www.nichcy.org Tel: 800-695-0285 Fax: 202-884-8441 |
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Last updated February 13, 2007