Deng Xueyun, Liu Lizhen, Zhen Zhiming, Chen Quan, Liu Lihua, Hui Xuhui
Department of Neurosurgery, The Affiliated Nanchong Central Hospital of North Sichuan Medical College, Nanchong, China.
Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, China.
Front Psychiatry. 2022 Aug 1;13:968859. doi: 10.3389/fpsyt.2022.968859. eCollection 2022.
Acoustic neuroma (AN) is a clinically common benign tumor. There are few neuropsychological investigations for AN, especially cognitive neuropsychology. Herein, the study probed into cognitive function changes in AN patients and expounded possible mechanisms through structural and functional magnetic resonance imaging (fMRI).
Neuropsychological tests were performed between 64 patients with AN and 67 healthy controls. Then, using resting-state fMRI, the possible mechanisms of cognitive decline in AN patients were further explored by calculating the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo). Furthermore, using high-resolution T1-weighted images, voxel-based morphometry (VBM) was adopted to investigate the changes in gray matter volume (GMV) and white matter volume (WMV) in AN patients.
AN patients had worse cognitive performance than those in the healthy controls. Relative to the healthy individuals, the mALFF value was increased in the right caudate nucleus of the patients with left-sided AN (LAN) and the right rectus region of the patients with right-sided AN (RAN). The mReHo values of the bilateral superior frontal gyrus and middle frontal gyrus were decreased in LAN patients. Compared with healthy subjects, the GMV values were elevated in the left fusiform gyrus, parahippocampal gyrus, calcarine gyrus, and cuneus in LAN patients as well as in the right fusiform gyrus and parahippocampal gyrus in RAN patients. Meanwhile, the WMV values showed elevations in the bilateral putamen, left rectal gyrus, and thalamus in LAN patients.
Cognitive dysfunction occurs in AN patients. Cognitive decline in AN patients activates functional activity in some brain regions, thereby compensating for cognition decline. Additionally, the ReHo values were reduced in the frontal lobe in LAN patients, and the connectivity was decreased, affecting the functional differentiation and integration of the brain, which may be associated with the decline in cognitive function. Lateralized brain reorganization induced by unilateral hearing loss was presented in AN patients. LAN caused a more significant interference effect on the brain while RAN patients showed more stable cerebral cortices. Altogether, responding to cognition decline in AN patients, structural reorganization occurs, and compensative increases in cognitive-related brain regions, which compensates for cognitive impairment.
听神经瘤（AN）是一种临床常见的良性肿瘤。针对听神经瘤的神经心理学研究较少，尤其是认知神经心理学方面。在此，本研究探讨了听神经瘤患者的认知功能变化，并通过结构和功能磁共振成像（fMRI）阐述了可能的机制。
对64例听神经瘤患者和67例健康对照者进行了神经心理学测试。然后，利用静息态fMRI，通过计算低频振幅（ALFF）和局部一致性（ReHo）进一步探索听神经瘤患者认知衰退的可能机制。此外，使用高分辨率T1加权图像，采用基于体素的形态学测量（VBM）来研究听神经瘤患者灰质体积（GMV）和白质体积（WMV）的变化。
听神经瘤患者的认知表现比健康对照者差。相对于健康个体，左侧听神经瘤（LAN）患者右侧尾状核和右侧听神经瘤（RAN）患者右侧直肌区域的平均ALFF值升高。LAN患者双侧额上回和额中回的平均ReHo值降低。与健康受试者相比，LAN患者左侧梭状回、海马旁回、距状回和楔叶以及RAN患者右侧梭状回和海马旁回的GMV值升高。同时，LAN患者双侧壳核、左侧直回和丘脑的WMV值升高。
听神经瘤患者存在认知功能障碍。听神经瘤患者的认知衰退激活了一些脑区的功能活动，从而补偿认知衰退。此外，LAN患者额叶的ReHo值降低，连接性下降，影响大脑的功能分化和整合，这可能与认知功能下降有关。听神经瘤患者出现了由单侧听力损失引起的大脑偏侧化重组。LAN对大脑的干扰作用更显著，而RAN患者的大脑皮层更稳定。总之，为应对听神经瘤患者的认知衰退，发生了结构重组，与认知相关的脑区出现代偿性增加，从而补偿认知障碍。
