Becker-Bense Sandra, Dieterich Marianne, Buchholz Hans-Georg, Bartenstein Peter, Schreckenberger Mathias, Brandt Thomas
Department of Neurology, Ludwig-Maximilians-University Munich, Marchioninistrasse 15, 81377, Munich, Germany,
Brain Struct Funct. 2014 Jul;219(4):1355-67. doi: 10.1007/s00429-013-0573-z. Epub 2013 May 18.
The human vestibular system is represented in the brain bilaterally, but it has functional asymmetries, i.e., a dominance of ipsilateral pathways and of the right hemisphere in right-handers. To determine if acute right- or left-sided unilateral vestibular neuritis (VN) is associated with differential patterns of brain metabolism in areas representing the vestibular network and the visual-vestibular interaction, patients with acute VN (right n = 9; left n = 13) underwent resting state (18)F-FDG PET once in the acute phase and once 3 months later after central vestibular compensation. The contrast acute vs. chronic phase showed signal differences in contralateral vestibular areas and the inverse contrast in visual cortex areas, both more pronounced in VN right. In VN left additional regions were found in the cerebellar hemispheres and vermis bilaterally, accentuated in severe cases. In general, signal changes appeared more pronounced in patients with more severe vestibular deficits. Acute phase PET data of patients compared to that of age-matched healthy controls disclosed similarities to these patterns, thus permitting the interpretation that the signal changes in vestibular temporo-parietal areas reflect signal increases, and in visual areas, signal decreases. These data imply that brain activity in the acute phase of right- and left-sided VN exhibits different compensatory patterns, i.e., the dominant ascending input is shifted from the ipsilateral to the contralateral pathways, presumably due to the missing ipsilateral vestibular input. The visual-vestibular interaction patterns were preserved, but were of different prominence in each hemisphere and more pronounced in patients with right-sided failure and more severe vestibular deficits.
人类前庭系统在大脑中双侧存在，但具有功能不对称性，即右利手者同侧通路和右半球占优势。为了确定急性右侧或左侧单侧前庭神经炎（VN）是否与前庭网络和视前庭相互作用相关脑区的脑代谢差异模式有关，急性VN患者（右侧9例；左侧13例）在急性期和中枢前庭代偿后3个月各进行一次静息态（18）F-FDG PET检查。急性期与慢性期的对比显示对侧前庭区域有信号差异，而视觉皮层区域则相反，右侧VN更为明显。左侧VN在双侧小脑半球和蚓部还发现了其他区域，严重病例更为突出。一般来说，前庭功能缺损越严重的患者信号变化越明显。与年龄匹配的健康对照相比，患者急性期PET数据与这些模式相似，因此可以解释为前庭颞顶叶区域的信号变化反映信号增强，而视觉区域的信号变化反映信号减弱。这些数据表明，右侧和左侧VN急性期的脑活动表现出不同的代偿模式，即主要的上行输入从同侧通路转移到对侧通路，可能是由于同侧前庭输入缺失。视前庭相互作用模式得以保留，但在每个半球的突出程度不同，右侧功能障碍和前庭功能缺损更严重的患者更为明显。
