Many children with Miller-Dieker syndrome (MDS) do not live past age 2, and only a few may reach age 10. According to GeneReviews, as of 2014, the oldest known individual with MDS died at age 17 years. In general, life expectancy is related to the severity of the lissencephaly. The most common cause of death is aspiration pneumonia, caused by poor control of the airways.
The developmental outlook is poor for all children with MDS, but varies slightly based on the degree of the brain malformation. The highest developmental level in affected children is the equivalent of about 3 to 5 months of age, even with good seizure control. Very rarely, a child may be able to sit without help. Children with poor seizure control may function only at or below the level of a newborn.
Last updated: 5/18/2016
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