摘要
目的利用血氧水平依赖性功能磁共振成像(BOLD-fMRI)视网膜脑图技术(retinotopic mapping),研究屈光参差性弱视皮层功能损害的发生机制。资料与方法以1.5TMRI系统采集8例单眼屈光参差性弱视患者枕叶视觉皮层对于视网膜脑图刺激和6cpd空间频率黑白光点刺激的功能数据,比较弱视眼和健眼在初、高级视觉皮层功能区功能反应;对初、高级皮层间功能损害进行回归分析。结果弱视眼在V1、V2、V3、VP、V7区反应T值低于健眼(P<0.05),在V3a、V4、V8区弱视眼与健眼T值无统计学差异;V1区与V2、V3、VP、V7区之间反应减低相关分析无统计学意义(P>0.05)。结论弱视患者初、高级视觉皮层均存在功能损害,两者之间无明显因果关系;在高级视觉皮层,背、腹侧传导通路均有功能损害;fMRI视网膜脑图技术为深入研究弱视初、高级视觉皮层功能损害的发病机制提供了新的方法。
Objective To study the mechanism of visual cortical deficit in patients with anisometropic amblyopia with BOLD-fMRI retinotopic mapping. Materials and Methods Eight anisometropic amblyopes underwent fMRI with retinotopic mapping and dots stimuli （ 6cpd, 4Hz, 0.5 ）. 1.5T MRI system was used to obtain functional images of visual cortex. Responses of the amblyopic and fellow fixing eye were compared in primary and secondary visual cortex. The fMRI deficits were analyzed regressively. Results Amblyopic eyes showed significantly less activation （T value） in V1, V2, V3, VP and V7 visual area compared with fixing eyes （P 〈0.05）. There were no statistic differences in V3a, V4 and V8 area （P 〉 0.05 ） between the two eyes. No causal relations were found between the activation loss of striate and extra-striate cortex （P 〉 0.05）. Conclusion There are functional deficits in both primary and secondary visual cortex without causal relationship in amblyopes. The dorsal and ventral visual pathways are all affected in secondary visual cortex. FMRI retinotopic mapping provides a new way to investigate primary and secondary visual cortex deficit in amhlyopes.
出处
《临床放射学杂志》
CSCD
北大核心
2008年第6期721-725,共5页
Journal of Clinical Radiology
基金
国家自然科学基金资助项目(编号:30670600)
