Abnormal patterns of cortical gyrification in velo-cardio-facial syndrome (deletion 22q11.2): An MRI study

Schaer, Marie; Eric Schmitt, J.; Glaser, Bronwyn; Lazeyras, François; Delavelle, Jacqueline; Eliez, Stephan

doi:10.1016/j.pscychresns.2005.10.002

« Previous Next »Psychiatry Research: Neuroimaging
Volume 146, Issue 1 , Pages 1-11, 30 January 2006

Abnormal patterns of cortical gyrification in velo-cardio-facial syndrome (deletion 22q11.2): An MRI study

Marie Schaer
- Service Médico-Pédagogique, Department of Psychiatry, University of Geneva School of Medicine, Geneva, Switzerland
J. Eric Schmitt
- Department of Psychiatry and Human Genetics, VCU Medical Center, Virginia Commonwealth University, Richmond, VA, USA
Bronwyn Glaser
- Service Médico-Pédagogique, Department of Psychiatry, University of Geneva School of Medicine, Geneva, Switzerland
François Lazeyras
- Department of Radiology, University of Geneva Hospitals, Geneva, Switzerland
Jacqueline Delavelle
- Department of Radiology, University of Geneva Hospitals, Geneva, Switzerland
Stephan Eliez
- Service Médico-Pédagogique, Department of Psychiatry, University of Geneva School of Medicine, Geneva, Switzerland
- Department of Genetic Medicine and Development, University of Geneva School of Medicine, Geneva, Switzerland
- Corresponding author. Service Médico-Pédagogique, University of Geneva School of Medicine, Boulevard Saint Georges 16-18, Case postale 50, CH-1211 Geneva 8, Switzerland. Tel.: +41 22 327 43 00; fax: +41 22 327 43 20.

Received 8 February 2005; received in revised form 29 September 2005; accepted 1 October 2005.

Abstract

Velo-cardio-facial syndrome (VCFS), also known as 22q11.2 deletion syndrome, is a common genetic condition associated with increased risk for developing schizophrenia. Given that cortical malformations play an integral role in the pattern of neuroanatomical alterations associated with VCFS, the aim of the present study was to quantify and localize gyral abnormalities. Magnetic resonance images were obtained on a 1.5 T scanner. The gyrification index (GI), a measure of the degree of cortical complexity, was differentially calculated for each lobe using a semi-automated protocol. The GI was calculated for 37 patients affected by VCFS as well as for 36 comparison individuals group-matched for age, handedness, and gender. The subjects affected by VCFS showed a significant decrease in the GI in the frontal and parietal lobes compared with the control group. The pattern of decreased gyrification in the frontal and parietal lobes further defines the structural changes associated with the syndrome and suggests underlying abnormalities in neural connectivity. Aberrant connectivity may be partially responsible for the cognitive and behavioral impairments in the syndrome, as well as the high incidence of schizophrenia among affected individuals.

Keywords: 22q11 deletion syndrome, VCFS, Gyrification index, Schizophrenia, Cortical complexity