Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Print friendly version


Other Names for this Disease
  • Macrencephaly
  • Unilateral Megalencephaly
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Your Question

My grandson was recently diagnosed with hemimegalencephaly.  He's currently on-track developmentally.  Are there degrees of severity with this condition?  Where can we find the best information or an expert we could talk to?

Our Answer

We have identified the following information that we hope you find helpful. If you still have questions, please contact us.

Are there degrees of severity with hemimegalencephaly?  

Yes, hemimegalencephaly and the symptoms associated with it can range from mild to severe.[1]  Individuals with hemimegalencephaly and normal intellectual development have been described in the medical literature.[2]  Some researchers have suggested that mildly affected individuals are less likely to be identified as having this condition.[1]
Last updated: 11/28/2012

How can I find a genetics professional in my area?

Genetics clinics are a source of information for individuals and families regarding genetic conditions, treatment, inheritance, and genetic risks to other family members. More information about genetic consultations is available from Genetics Home Reference. To find a genetics clinic, we recommend that you contact your primary healthcare provider for a referral.

The following online resources can help you find a genetics professional in your community:

Last updated: 11/28/2012

  • Flores-Sarnat L. Hemimegalencephaly: part 1. Genetic, clinical, and imaging aspects. Journal of child neurology. 2002; 17:373-384. Accessed 11/27/2012.
  • Fusco L, Ferracuti S, Fariello G, Manfredi M, Vigevano F. Hemimegalencephaly and normal intellectual development. Journal of neurology, neurosurgery, and psychiatry. 1992; 55:720-722. Accessed 11/27/2012.