Byington Caroline G, Goodman Adam M, Allendorfer Jane B, Correia Stephen, LaFrance W Curt, Szaflarski Jerzy P
Department of Neurology, UAB Epilepsy Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Department of Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Epilepsia. 2024 Apr;65(4):1060-1071. doi: 10.1111/epi.17896. Epub 2024 Jan 31.
The uncinate fasciculus (UF) has been implicated previously in contributing to the pathophysiology of functional (nonepileptic) seizures (FS). FS are frequently preceded by adverse life events (ALEs) and present with comorbid psychiatric symptoms, yet neurobiological correlates of these factors remain unclear. To address this gap, using advanced diffusion magnetic resonance imaging (dMRI), UF tracts in a large cohort of patients with FS and pre-existing traumatic brain injury (TBI + FS) were compared to those in patients with TBI without FS (TBI-only). We hypothesized that dMRI measures in UF structural connectivity would reveal UF differences when controlling for TBI status. Partial correlation tests assessed the potential relationships with psychiatric symptom severity measures.
Participants with TBI-only (N = 46) and TBI + FS (N = 55) completed a series of symptom questionnaires and MRI scanning. Deterministic tractography via diffusion spectrum imaging (DSI) was implemented in DSI studio (https://dsi-studio.labsolver.org) with q-space diffeomorphic reconstruction (QSDR), streamline production, and manual segmentation to assess bilateral UF integrity. Fractional anisotropy (FA), radial diffusivity (RD), streamline counts, and their respective asymmetry indices (AIs) served as estimates of white matter integrity.
Compared to TBI-only, TBI + FS participants demonstrated decreased left hemisphere FA and RD asymmetry index (AI) for UF tracts (both p < .05, false discovery rate [FDR] corrected). Additionally, TBI + FS reported higher symptom severity in depression, anxiety, and PTSD measures (all p < .01). Correlation tests comparing UF white matter integrity differences to psychiatric symptom severity failed to reach criteria for significance (all p > .05, FDR corrected).
In a large, well-characterized sample, participants with FS had decreased white matter health after controlling for the history of TBI. Planned follow-up analysis found no evidence to suggest that UF connectivity measures are a feature of group differences in mood or anxiety comorbidities for FS. These findings suggest that frontolimbic structural connectivity may play a role in FS symptomology, after accounting for prior ALEs and comorbid psychopathology severity.
钩束（UF）先前被认为与功能性（非癫痫性）发作（FS）的病理生理学有关。FS之前常伴有不良生活事件（ALE），并伴有共病精神症状，但这些因素的神经生物学相关性仍不清楚。为了填补这一空白，我们使用先进的扩散磁共振成像（dMRI），将一大群患有FS且有创伤性脑损伤病史的患者（TBI+FS）的UF束与没有FS的创伤性脑损伤患者（仅TBI）的UF束进行比较。我们假设，在控制TBI状态时，dMRI对UF结构连接性的测量将揭示UF的差异。偏相关检验评估了与精神症状严重程度测量值之间的潜在关系。
仅患有TBI的参与者（N=46）和TBI+FS的参与者（N=55）完成了一系列症状问卷和MRI扫描。在DSI studio（https://dsi-studio.labsolver.org）中通过扩散谱成像（DSI）实施确定性纤维束成像，采用q空间微分同胚重建（QSDR）、流线生成和手动分割来评估双侧UF的完整性。分数各向异性（FA）、径向扩散率（RD）、流线计数及其各自的不对称指数（AI）作为白质完整性的估计值。
与仅患有TBI的患者相比，TBI+FS的参与者表现出左侧半球UF束的FA和RD不对称指数（AI）降低（均p<.05，经错误发现率[FDR]校正）。此外，TBI+FS在抑郁、焦虑和创伤后应激障碍测量中的症状严重程度更高（均p<.01）。将UF白质完整性差异与精神症状严重程度进行比较的相关检验未达到显著标准（均p>.05，经FDR校正）。
在一个大型、特征明确的样本中，患有FS的参与者在控制TBI病史后白质健康状况下降。计划中的随访分析没有发现证据表明UF连接性测量是FS患者情绪或焦虑共病组间差异的一个特征。这些发现表明，在考虑了先前的ALE和共病精神病理学严重程度后，额边缘结构连接性可能在FS症状学中起作用。
