دانلود رایگان مقاله انگلیسی دوره سلول های سرطانی در مبتلایان به اوتیسم: داده های تصویربرداری مغز اوتیسم- الزویر 2018

ABSTRACT

BACKGROUND: The neuroanatomical bases of autism spectrum disorder remain largely unknown. Among the most widely discussed candidate endophenotypes, differences in cerebellar volume have been often reported as statistically significant. METHODS: We aimed at objectifying this possible alteration by performing a systematic meta-analysis of the literature and an analysis of the ABIDE (Autism Brain Imaging Data Exchange) cohort. Our meta-analysis sought to determine a combined effect size of autism spectrum disorder diagnosis on different measures of the cerebellar anatomy as well as the effect of possible factors of variability across studies. We then analyzed the cerebellar volume of 328 patients and 353 control subjects from the ABIDE project. RESULTS: The meta-analysis of the literature suggested a weak but significant association between autism spectrum disorder diagnosis and increased cerebellar volume (p = .049, uncorrected), but the analysis of ABIDE did not show any relationship. The studies meta-analyzed were generally underpowered; however, the number of statistically significant findings was larger than expected. CONCLUSIONS: Although we could not provide a conclusive explanation for this excess of significant findings, our analyses would suggest publication bias as a possible reason. Finally, age, sex, and IQ were important sources of cerebellar volume variability, although independent of autism diagnosis.

DISCUSSION

Neuroanatomical diversity appears to account for a substantial proportion of the risk for ASD (29). However, and even though several candidate neuroanatomical biomarkers have been proposed, it is not yet clear exactly which neuroanatomical traits more strongly influence diagnosis. In this report, we looked at one specific structure, the cerebellum, that has been widely discussed in the literature. We performed a metaanalysis of the literature and an analysis of data from the ABIDE project.

The meta-analysis of the literature did not show conclusive evidence for a difference between patients with ASD and control subjects either for the total cerebellar volume or for its subregions. Total cerebellar volume and cerebellar white matter volume appeared slightly larger in ASD, whereas the area of vermal lobules VI–VII was found to be slightly smaller in ASD, but the significance of these results did not survive correction for multiple comparisons. Compared with a previous meta-analysis on total cerebellar volume and vermal areas (25), the effect sizes we computed were all smaller in absolute value. Specifically, Stanfield et al. (25) reported a significant difference in the volume of vermal lobules VIII–X. In our analysis, despite the fact that a larger number of studies was taken into account, we did not replicate their finding