Zina Z. Rozhkova PhD, DSc, Presenter: Nothing to Disclose

Oleksii Omelchenko, Abstract Co-Author: Nothing to Disclose

We propose amplitude of low-frequency fluctuations ALFF, and values of the fractional ALFF (fALFF), and also the ratios of the main cerebral metabolites for the characteristics of functional and metabolic abnormalities of autism.

26 children are examined by fMRI and 1HMRS using 1.5T Signa EXCITE HD (GE). All subjects are divided into two groups. The 1st group (NG) consists of 8 healthy children (3-16yo). The 2nd group (PG) includes 18 (3-14yo) autistic chidren. For all subjects T2*W-GE-EPI(TR/TE=3000/71ms) were obtained. Single, and group ICA analysis using MELODIC were carried out. The frequency fluctuations of the BOLD signal in the range 0.0024-0.167 were measured. ALFF and fALFF were calculated using REST software, and analyzed in two different frequency bands (slow-5:0.01-0.027Hz, slow-4:0.027-0.073Hz). To detect the differences of ALFF and fALFF in two groups for all voxels in the gray matter (GM) the GLM was applied. 1H spectra are recorded with STEAM:TR/TE=1500/144ms in both hemispheres in the white and gray matter (WM, GM).  

In PG decreasing ALFF of both frequency bands and fALFF of slow-5 band, including left inferior/middle/superior temporal gyrus, left inferior parietal gyrus, left supramarginal gyrus, left angular gyrus, left fusiform gyrus, left middle occipital gyrus are found. In PG in slow-4 band fALFF decreased in right inferior/middle/superior temporal gyrus, right supramarginal gyrus, right angular gyrus, right fusiform gyrus, and right lateral cerebellum. In contrast, ALFF of slow-5 band increased in bilateral brainstem, cerebellar vermis, media cerebellum, and left parahippocampal gyrus. Frequency-specific ALFF/fALFF abnormalities in PG are associated with deficit of social cognition. In PG decrease of NAA/Cr, increase of Cho/Cr, and mIns/Cr in anterior cingulate and left striatum in comparison with NG are obtain. In WM in the NG in the age 3-6y the Glu/Cr increase rapidly from (0.23+-0.02), reach maximum in 6y (0.34+-0.02), and thereafter decreased moderately to adults level (0.30+-0.02) for the age 8y. In GM in the NG in the age 3-6y the Glu/Cr (0.28+-0.02) increase rapidly before values (0.36+-0.03), characteristic for adult level.

fMRI and MRS gives us a possibility for monitoring of the brain functional development in the norm and under pathology.

We combined these methods to understanding of the mechanisms of autism formation.

Rozhkova, Z, Omelchenko, O, Alterations of the Regional Low-frequency Fluctuation and Peculiarities of the Brain Metabolism in Autistic Children: fMRI and In-vivo 1H MRS Study.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045435.html