A rare cerebral malformation characterized by an almost or complete lack of cortex specifically the cerebral hemispheres with the cranium and meninges completely intact. In most cases death occurs in utero or in the first weeks of life. Developmental delay drug-resistant seizures spastic diplegia severe growth failure deafness and blindness are typical.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version April 2026
Newly diagnosed with
Hydranencephaly?
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Advocacy Organizations
Global Hydranencephaly Foundation
We work to ensure the preservation of human rights for people with hydranencephaly, a rare neurological condition.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.