ENLARGED SYLVIAN FISSURES IN INFANTS WITH INTERSTITIAL DELETION OF CHROMOSOME 22Q11

Two infants with chromosome 22q11 deletion syndrome were noted to have symmetrically enlarged Sylvian fissures on cranial MRI. We compared t he size of the Sylvian fissures in neuroimaging studies from 17 other subjects with del 22q11 to age-matched disease controls. The mean ante rior interopercular distance was used as an index of Sylvian fissure e nlargement. Symmetric enlargement of the Sylvian fissures was present in 10 of 17 subjects with del 22q11. The age-incidence pattern, as wel l as follow-up scans in 2 patients, suggests delayed growth of the ope rcular region in these patients. Subjects with del 22q11 consistently had disproportionate enlargement of the left Sylvian fissure compared to the right. This observation suggests that a gene (or genes) in the deleted region affects the development of the left and right perisylvi an cortex in different ways. Abnormal development of the operculum may explain some of the neurodevelopmental features that are common among individuals with 22q11 deletion syndrome. (C) 1997 Wiley-Liss, Inc.