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Introduction: Functional neuroimaging studies have been conducted to investigate cognitive and behavioral dysfunctions in locked-in syndrome (LIS). This study, we used a multimodal neuroimaging approach to investigate functional and structural connectivity in a LIS patient. Case Report: A 39-year-old patient who was in a total locked-in state was admitted in our department. The Coma Recovery Scale-Revised score, event-related potential, and ultra–high-field 7 T magnetic resonance imaging (MRI) were used to investigate this patient. White matter connectometry and seed-based resting-state functional connectivity analysis were used to compare the patient with an age-matched, sex-matched healthy control. Diffusion MRI findings indicated that fibers in the brainstem significantly decreased, especially in the cross region of pons, whereas the fibers above the brainstem in the deep brain increased particularly in the posterior cingulate cortex (PCC), the left parietal lobe, and parts of the corpus callosum. Meanwhile, using the PCC as the seed region, the functional connectivity between PCC and left parietal and occipital lobes, right occipital and temporal lobes increased, respectively, especially in the area of left inferior parietal gyrus and the postcentral gyrus, which were in accordance with the most increased fiber density areas observed in diffusion MRI. Conclusions: These results provide tentative evidences to reveal the important role of PCC and corpus callosum in the LIS patient. These findings may be informative to the study of patients with LIS. [ABSTRACT FROM AUTHOR]

Purpose: To intraindividually compare the delineation of intracranial arterial vasculature in nonenhanced versus contrast-enhanced magnetization prepared rapid gradient echo (MPRAGE) imaging at 7 Tesla (T). Materials and Methods: Sixteen subjects were examined on a 7 T whole-body magnetic resonance system (Magnetom 7T) equipped with a 32-channel transmit/receive head coil. MPRAGE imaging was performed pre- and postcontrast after the application of 0.1 mmol/kg bodyweight gadobutrol. For qualitative analysis, the delineation of the intracranial arteries, overall image quality, and image impairment were assessed in the nonenhanced and contrast-enhanced datasets using a 5-point scale (5 = excellent to 1 = nondiagnostic). Additionally, contrast ratios (CR) of the middle cerebral artery in correlation to surrounding gray matter in nonenhanced and postcontrast images were obtained. For statistical analysis a Wilcoxon signed-rank test was applied. Results: Nonenhanced MPRAGE imaging offered an excellent delineation of the central vessel segments of the anterior circulation (mean anterior circulation 4.6) and a moderate- to high-quality assessment of the vessels of the posterior circulation (mean posterior circulation 3.9). Vessel delineation was improved in all assessed segments in the contrast-enhanced datasets, except for the cavernous segment of the internal carotid artery. Quantitative analysis revealed a mild, nonsignificant increase in CR mean values of the M1 segment (CRnonenhanced 0.67; CRcontrast-enhanced 0.69). Conclusion: Our results demonstrate the high diagnostic value of nonenhanced 7 T MPRAGE imaging for the assessment of the intracranial arterial vasculature, with improved assessment of the peripheral segments because of the application of a contrast agent. [ABSTRACT FROM AUTHOR]