The functional MRI study of the visual cortical function's rebuilding in children ametropic amblyopia

Abstract

Objective To research the recovery of the visual cortical function mediating visual motion perception in ametropic amblyopia after regular amblyopia treatment using 3.0 Tesla functional MRI (fMRI).Methods In this prospective study,blocks-designed fMRI experiment was performed on nine children with first was diagnosed as ametropic amblyopia,and review fMRI after one week,two weeks and one month.During the study,the patients were asked to view stimuli through rotating the checkerboard,which contrast ratio approach to 100％ and frequency approach to 8 Hz,Functional MRI data were processed by using SPM8 which based on the Matlab 7.12.The matrix data of each treatment stage were acquired bv hypothesisdriven research,and before and after self-control study (matched t-test) was performed in each group to acquire average cerebral cortex activated functional images data.The different mapping between each group during visual motion stimulus was also acquired.Results The functional area that is bilateral occipital lobe (Mean t of the right BA18=1.236 1 ;Mean t of the left BA18=1.521 1; Mean t of the right BA19=1.6845; Mean t of the left BA19=1.591 7,P＜0.005) and the visual association area (V5) (The right BA37 was activated and Mean T=1.201 4;The right BA21 was activated and Mean t=1.145 0,P＜0.005) expanded in different levels after amblyopia treatment two weeks; After four weeks,the bilateral occipital lobe (Mean t of the right BA18=1.0024; Mean t of the left BA18=1.743 1; Mean t of the right BA19=1.2253; Mean t of the left BA19=1.181 3,P＜0.005) showed activation on the small area compare with two weeks ago.Conclusion In the early functional training of the older children's ametropic amblyopia,reconstruction the visual cortical function mediating visual motion perception was more difficulty and unstable. Key words: Children ; Amblyopia; Cerebral cortex ; Magnetic resonance imaging