Mean intensities and standard deviations were calculated for each volume in both participants and used for nonparametric testing (Wilcoxon rank-sum test) followed by a correction for multiple comparisons (Holm 1979), adjusting P-values for testing multiple hypotheses on effects pertaining to the 14 selected subcortical structures. Results For volumetry and assessment of quantitative correlates of vascularization, subcortical segmentation of gradient echo sequences and the respective TOF MR-angiography volumes was performed using the FreeSurfer image analysis suite (Fig. (Fig.1).1). Assessment of whole-brain TOF contrast indicated significantly
Inhibitors,research,lifescience,medical lower intensity values in subject #2 versus subject #1 for the Thalamus (left: Inhibitors,research,lifescience,medical −9.9%, P = 0.002, right: −10.0%, P = 0.003), right Caudate (−8.3%, P = 0.044), and
Pallidum (left: −17.3%, P = 0.011, right: −13.1%, P = 0.02). No significant differences in intensity were observed for the left Caudate (P = 0.07), Inhibitors,research,lifescience,medical Putamen (left: P = 1, right: P = 0.474), Hippocampus (left: P = 1, right: P = 1), Amygdala (left: P = 1, right: P = 1), and the Accumbens-area (left: P = 1, right: P = 1). Also mean intensity of all 14 structures was significantly lower in subject #2 than in subject #1 (−10%, Inhibitors,research,lifescience,medical means [SEM] subject #1: 82.9 [1.6]; subject #2: 75.0
[1.8]; P = 0.004). There was no significant difference between both subjects observable regarding total volume of the 14 subcortical gray-matter structures assessed (means [SEM] subject #1: 30.2 mL [6.1]; subject #2: 27.8 mL [5.9]; P = 0.078) (Table (Table11 and Fig. Fig.22). Table 1 Subcortical regions identified by the parcellation algorithm and estimated volumes Inhibitors,research,lifescience,medical for each participant, as well as differences in mean regional intensity and the respective T-test statistics Figure 1 (A and B) Reconstructed three-dimensional (3D) time-of-flight (TOF) images, demonstrating subcortical and cortical vessels originating from the main trunks of the cerebral arteries for both subjects assessed. (C) Indicates the subcortical brain areas … Figure 2 Mean values Carfilzomib (SEM) of total subcortical gray-matter intensity and total volume of the subcortical gray-matter structures assessed for subject #1 and #2. Discussion In this study, we quantified individual aging-related selleck chem decrease of subcortical gray-matter vascularization and selleck chemicals llc demonstrated most pronounced changes for brain regions in the Thalamus and Pallidum. By using 3D-TOF angiography at high field strength of 7T, high spatial resolution could be realized, allowing to take into account potential regional small vessel pathology.