FMRI Study Of Brodmann 17,18,19 In Visual Cortex For Anisometropia Amblyopia

Objective:To assess the activation changes in Brodmann 17 18 19 and to compare the cortex activations between before and after ametropia correction for anisometropic amblyopic eyes.Materials and Methods:Bold-fMRI technique on 1.5T SIMENS SONATA MRI was used. Blocks designation mode was used. The visual stimulus is a black-and-white checkerboard with frequencies of 1cycle /degree and 8 Hz. The baseline stimulus is a white cross-line at the center of the screen with black background. No other light or influence was allowed in the scanning room. The distance between the eyes and the screen was 0.6m.The experimental group included 10 anisometropic amblyopes. The control group was comprised of 8 volunteers. All amblyopic eyes were tested before and after ametropia correction and the fellow sound eyes were tested only after ametropia correction. For the control group both eyes were consequently tested after ametropia correction. Twenty axial imaging were collected parallel to the anterior–post commissure, which was identified with the aid of a sagittal localizer anatomical image. The functional image data was acquired with a echo-planar imaging(EPI) sequence. At the end of the experiment, anatomical reference images were collected using a three-dimensional, T1-weighted MPRAGE imaging sequence.All data obtained were analyzed online with"T-test"and offline with AFNI software. The threshold value was set to 0.001. During data processing, motion correction and three-dimensional smooth were used. Time-signal intensity curves and functional images could be obtained. After Talairach coordinating function images, the activation areas in Brodmann 17, 18 and 19 of every one were measured. The SPSS 12.0 software was used for statistic analysis.The cortical activations of amblyopic eyes before and after ametropia correction were...