Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.
Department of Otorhinolaryngology, Jena University Hospital, Jena, Germany; Department of Neurology, Hannover Medical School, Hannover, Germany.
Neuroscience. 2017 Sep 30;360:190-196. doi: 10.1016/j.neuroscience.2017.07.070. Epub 2017 Aug 7.
Impaired olfaction is associated with a volume decrease in the olfactory bulb as well as in the gray matter of cortical olfactory areas. On the other hand, restitution of an impaired olfaction results in a regain of volume in these regions. Studies investigating similar changes in the cerebral white matter are virtually not existent. The aim of this prospective study therefore was to investigate cerebral white matter using magnetic resonance diffusion tensor imaging (DTI). 31 patients (54±13years) with olfactory impairment (chronic rhinosinusitis) and planned functional endoscopic sinus surgery (FESS) were included. Magnetic resonance imaging (MRI) data sets were acquired pre-operatively and 3months after surgery. Pre- and postoperative olfactory testing was performed to assess the olfactory threshold, discrimination, and identification (TDI) score. A significant postoperative TDI improvement by 9.06±8.81 points was observed. Two groups were subsequently formed - one with relevant postoperative olfactory gain (ΔTDI≥10 points, 12 patients) and one without gain (ΔTDI<10 points, 19 patients). DTI parameter showed a significant correlation with the TDI score in the left anterior cingulate cortex and the right amygdala. In the group with relevant olfactory improvement higher values of fractional anisotropy and apparent diffusion coefficient were found in the right parahippocampal area and in the white matter below the left inferior temporal sulcus. Tract-specific diffusion property analysis revealed significant group differences in the cingulate cortex in spatial relationship to the perisplenial cortex. Overall, this prospective study indicates structural changes in white matter after postoperative restoration of olfaction.
嗅觉障碍与嗅球以及皮质嗅觉区域的灰质体积减少有关。另一方面，嗅觉障碍的恢复会导致这些区域的体积恢复。研究大脑白质相似变化的实际上并不存在。因此，这项前瞻性研究的目的是使用磁共振扩散张量成像（DTI）研究大脑白质。 31 名嗅觉障碍（慢性鼻鼻窦炎）和计划行功能性内窥镜鼻窦手术（FESS）的患者（54±13 岁）被纳入研究。在术前和术后 3 个月采集磁共振成像（MRI）数据集。进行术前和术后嗅觉测试，以评估嗅觉阈值、辨别力和识别（TDI）评分。观察到术后 TDI 显著改善 9.06±8.81 分。随后将患者分为两组 - 一组术后嗅觉明显改善（ΔTDI≥10 分，12 例），一组无改善（ΔTDI<10 分，19 例）。DTI 参数与左侧前扣带回皮质和右侧杏仁核的 TDI 评分呈显著相关性。在嗅觉明显改善的组中，右侧海马旁回和左颞下回下方的白质的各向异性分数和表观扩散系数值较高。束特异性扩散特性分析显示，扣带回皮质与围绕脾的皮质之间的空间关系存在显著的组间差异。总体而言，这项前瞻性研究表明嗅觉恢复后的结构变化与嗅觉有关。
