Department of Neurosurgery and Neurotechnology, Eberhard Karls University Hospital, Hoppe-Seyler-Straße 3, 72076, Tuebingen, Germany.
Department of Diagnostic and Interventional Neuroradiology, Eberhardt Karls University Hospital, Tuebingen, Germany.
Sci Rep. 2021 Apr 16;11(1):8411. doi: 10.1038/s41598-021-87915-3.
Tinnitus is attributed to partial sensory deafferentation resulting in a central maladaptive neuroplasticity. Unfortunately, the agent of deafferentation is usually unknown or irreversible. In patients with unilateral vestibular schwannoma (VS), however, the auditory nerve is affected by a benign tumor. Hence, removal of the tumor can cease the tinnitus. In turn, sustaining complaints after surgery indicate cortical neuroplasticity. The present study is a cross sectional study which aims to track cortical structural changes by surface-based morphometry in 46 VS patients with sustained (i.e. centralized) or ceased (i.e. peripheral) tinnitus after surgery. A volumetric analysis of cortical and subcortical gray matter (GM) anatomy was performed on preoperative high-resolution MRI and related to the presence of hearing impairment, pre- and/or postoperative tinnitus. Patients with sustained (i.e. chronic) tinnitus showed an increased GM volume of the bilateral caudate nucleus, the contralateral superior colliculus, the middle frontal and middle temporal gyrus, the fusiform gyrus as well as the ipsilateral pars orbitalis when compared to those patients in whom tinnitus ceased postoperatively. Chronic tinnitus in VS patients is associated with characteristic structural changes in frontal, temporal and subcortical areas. Notably, a significant GM change of the caudate nucleus was detected providing further support for the striatal gaiting model of tinnitus.
耳鸣归因于部分感觉传入缺失，导致中枢适应不良的神经可塑性。不幸的是，传入缺失的原因通常是未知的或不可逆转的。然而，在单侧前庭神经鞘瘤（VS）患者中，听神经受到良性肿瘤的影响。因此，切除肿瘤可以停止耳鸣。相反，手术后仍有抱怨表明存在皮质神经可塑性。本研究为一项横断面研究，旨在通过表面形态计量学追踪 46 例 VS 患者手术后持续（即集中）或停止（即外周）耳鸣的皮质结构变化。对术前高分辨率 MRI 进行皮质和皮质下灰质（GM）解剖的容积分析，并与听力损伤、术前和/或术后耳鸣的存在相关。与术后耳鸣停止的患者相比，持续（即慢性）耳鸣的患者双侧尾状核、对侧上丘、中额回和中颞回、梭状回以及同侧眶部的 GM 体积增加。VS 患者的慢性耳鸣与额、颞和皮质下区域的特征性结构变化有关。值得注意的是，检测到尾状核 GM 显著变化，为耳鸣的纹状体步态模型提供了进一步支持。
