자기공명영상을 이용한 대뇌 피질의 시간에 따른 경계 변화 분석

Abstract

Quantitative measurement of brain size, shape, and temporal change is increasingly important in biomedical image analysis applications. Imaging studies of anatomic changes in regional gray matter volumes and cortical thickness have documented age effects in many brain regions, but the majority of such studies have been cross-sectional investigations of individuals studied at a single point in time. We examined the surface boundary shift measurement of all subjects for individual pattern of the surface boundary shift change. The participants for this study consisted of 13 healthy elderly adults (mean± SD : 66.8± 0.9years) and 19 AD patients (mean± SD : 70.1± 7.6years). And then local differences of surface boundary shift change in each group of AD and NL, respectively were investigated within whole vertex using one-sample t-test. For group differences between NL and AD of surface boundary shift change, we performed two sample t-test on whole vertex. There are 40,962 vertices in cortical surface model, and correction of the thresholds for multiple comparisons was needed to control the false-positive rate. The false discovery rate (FDR)-controlling procedure for multiple comparisons was reported to be effective for the analysis of neuroimaging data We performed FDR correction for multiple comparisons at P < 0.05. Our results showed that the algorithm was successful in detecting longitudinal change of gray and white cortical surfaces. These results suggest that although studies using surface based registration, the surface boundary shift measurement is applicable for analysis of longitudinal data sets, such as those typically acquired for clinical trials of patients or age effect. In future studies, our measurement will be used to analyze longitudinal changes of cortical atrophy in larger groups of MS patients and control subjects in order to determine the clinical significance of cortical thinning.