Intracranial abnormalities detected by three-dimensional magnetic resonance imaging in Prader-Willi syndrome

Miller JL, Couch JA, Schmalfuss I, He G, Liu Y, Driscoll DJ.

Am J Med Genet A. 2006 Nov 13 

Prader-Willi Syndrome and its associated neurologic pathology have been grossly understudied.  In this study, the researchers used three dimensional magnetic resonance imaging to compare 20 individuals with PWS ranging in age from 3 months to 39 years, 21 normal weight siblings and 16 individuals with early onset morbid obesity.  The findings revealed abnormalities which included Ventriculomegaly in all 20 individuals with PWS.  Ventriculomegaly is described as an enlargement of the lateral ventricles between 10mm and 15 mm in width.  The brain has 4 fluid filled spaces that communicate with each other called ventricles.  Fluid produced with the brain circulates through the ventricles of the brain and around the spinal cord.  The lateral ventricles may become enlarged if the outflow of fluid from the lateral ventricles is blocked at the interventricular foramen.   

Polymicrogyria (PMG) was observed in the sylvian fissure in 13 patients along with partial insular closure.  The surface of the brain contains folds called gyri.  The condition referred to as Polymicrogyria (PMG) is merely descriptive from a radiologist’s viewpoint and is not considered a disease.  Some individuals, but not all, with PMG have some degree of global developmental delays, seizures, feeding difficulties, respiratory problems, motor dysfunction and mental retardation.   

None of the members of the control group (ie normal weight) demonstrated any brain alterations.  Many of the members of the PWS group demonstrated changes within the brain structure.  This suggests that those with paternal deletions in the chromosome 15q11-q13 region may have aberrant brain development. 

Abstract - click here

edited: 02/09/2012