Bing Yu MD, Presenter: Nothing to Disclose

Guoguang Fan PhD, Abstract Co-Author: Nothing to Disclose

Na Liu MD, Abstract Co-Author: Nothing to Disclose

Qiyong Guo MD, Abstract Co-Author: Nothing to Disclose

To investigate the effect of slight sedation with chloral hydrate (30mg/kg) used for fMRI on the BOLD response of children's visual cortex.  

Twelve healthy children (7 girls and 5 boys; age range from 5.7 to 6.5 years, with a median age of 6.0 years) were recruited . Written informed consent was provided by all the participants’ parents or legal guardians, and all procedures were performed under the approval of the institutional review board for clinical studies.The subjects were tested during awake state and under sedation following oral administration of 10% chloral hydrate (30mg/kg) . BOLD-fMRI scan was performed using a 3T MR scanner with visual flash at 2 Hz and their eyes were closed either in awake or sedative state during fMRI examination. Data analysis was performed by Statistical Parametric Mapping software (SPM2). The number of activated voxels in brodmann area (BA)17,18 and 19 were counted respectively. Meanwhile, quantitative analysis was performed using the regions of interest (ROI) method settled on the activated voxels in BA 17,18 and 19 , SPM toolbox MarsBar was used to engage statistical analyses of ROI data, percent signal change was measured . The the number of activated voxels and percent signal change of the children in awake and sedative state were analyzed by paired t test. A P value of less than 0.05 was considered to indicate statistical significance.

The active voxels in sedative state were less than in awake state, the active voxels in BA 17 were seen in all subjects either in awake or sedative state; BA 18 in 10 awake and 1 sedative subjects ;BA 19 in 9 awake and 2 sedative subjects. The BOLD percent signal change were negative in 5 of 12 subjects and positive in other 7 both in sedative and awake state . There were no statistical significance differences in number of active voxels or percent signal change in BA 17 between awake and sedative state(P>0.05).  

Slight sedation with chloral hydrate used for fMRI in children significantly reduce the reaction extent in associated visual cortex (BA 18 and 19) ,but have no significance effect on the BOLD response in primary visual cortex (BA 17) of children.  

Slight sedation with chloral hydrate used for fMRI have no significance effect on the BOLD response in primary visual cortex of children.  

Yu, B, Fan, G, Liu, N, Guo, Q, Effect of Slight Sedation on Visual Processing in Children: A Self-control fMRI Study.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6009872.html