A FAMILIAL SYNDROME OF UNILATERAL POLYMICROGYRIA AFFECTS THE RIGHT HEMISPHERE
Abstract number :
3.267
Submission category :
Year :
2005
Submission ID :
5271
Source :
www.aesnet.org
Presentation date :
12/3/2005 12:00:00 AM
Published date :
Dec 2, 2005, 06:00 AM
Authors :
1Bernard S. Chang, 1Kira A. Apse, 2Roberto Caraballo, 3J. Helen Cross, 4Richard Jacobson, 5Richard J. Leventer, 6Kette D. Valente, 7A. James Barkovich, and 1
Polymicrogyria (PMG) is a common malformation of cortical development that can arise from both genetic and environmental causes. A number of familial bilateral symmetric PMG syndromes have been described, but unilateral PMG is often assumed to be nongenetic in origin. We sought to identify familial cases of unilateral PMG. Patients with unilateral PMG were recruited at multiple different medical centers worldwide. Clinical and family histories, neurological examination results, and findings from diagnostic studies were reviewed. The diagnosis of PMG was made by brain MRI in all cases, with pathological confirmation in some. We identified five families in which unilateral PMG was present in more than one member. All had right-sided PMG. Four families had two affected siblings born to nonconsanguineous, unaffected parents. In one family, a mother and son both had unilateral right-sided PMG. Most cases were clinically characterized by the core features of contralateral hemiparesis, mental retardation / developmental delay, and focal seizures. On MRI, the cortical malformation was strikingly stereotyped between members of each family. Although all individuals shared right-sided perisylvian involvement, there was slight variability in anatomical distribution and severity among families. Our findings indicate that unilateral PMG exists in a familial syndrome of probable germline genetic origin. The right-sided preponderance both in our cases and in sporadic cases in the literature suggests a potential differential hemispheric susceptibility to this cortical malformation, which may reflect distinct aspects of human left and right perisylvian cortex development. (Supported by National Institute of Neurological Disorders and Stroke (K23 NS49159 to B.S.C. and R37 NS35129 to C.A.W.) and the Clinical Investigator Training Program (Beth Israel Deaconess Medical Center and Harvard-MIT Division of Health Sciences and Technology, in collaboration with Pfizer Inc.) to B.S.C. C.A.W. is an Investigator of the Howard Hughes Medical Institute.)