Mech-Sense, Department of Radiology, Aalborg University Hospital, Aalborg, Denmark.
Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.
Exp Clin Endocrinol Diabetes. 2022 May;130(5):327-334. doi: 10.1055/a-1347-2579. Epub 2021 Feb 1.
Thalamus is essential in processing of sensory information. This study explored the associations between thalamic volume and intra-thalamic metabolites and associations to clinical and experimental characteristics of sensory function in adults with diabetic polyneuropathy.
48 adults with type 1 diabetes and confirmed distal symmetric peripheral neuropathy (DPSN) and 28 healthy controls participated in a cross-sectional study and underwent a brain magnetic resonance imaging scan. Estimates for thalamic volume were extracted using voxel-based morphometry and intra-thalamic N-acetylaspartate/creatine (NAA/cre) levels were assessed by magnetic resonance spectroscopy. Associations between thalamic volume and clinical measures, quantitative sensory testing and neuropathic phenotype were explored.
In diabetes, reduced gray matter volume was identified including bilateral thalamus (all p≤0.001) in comparison to healthy participants. Thalamic volume estimates were positively associated to intra-thalamic NAA/cre (r=0.4; p=0.006), however not to diabetes duration (p=0.5), severity of DSPN (p=0.7), or presence of pain (p=0.3). Individuals with the lowest thalamic volume had greatest loss of protective sensation (light touch using von Frey-like filaments, p=0.037) and highest pain tolerance to electric stimulation (tetanic stimulation, p=0.008) compared to individuals with the highest thalamic volume.
In this cohort with type 1 diabetes and severe DSPN, thalamic atrophy was present and associated with reduced NAA/cre, indicating thalamic structural loss and dysfunction. Thalamic atrophy was associated to reduced sensory function involving large fiber neuropathy and sensation to tetanic stimulation that may reflect synaptic transmission. This may ultimately contribute to the current understanding of the pathophysiology behind the perception changes evident in DSPN.
丘脑在处理感觉信息方面至关重要。本研究探讨了成人 1 型糖尿病伴远端对称性多发性神经病变（DSPN）患者丘脑体积与丘脑内代谢物之间的相关性，以及这些相关性与感觉功能的临床和实验特征的关系。
48 例 1 型糖尿病伴确诊的远端对称性周围神经病变（DSPN）患者和 28 例健康对照者参与了一项横断面研究，并接受了脑部磁共振成像扫描。采用基于体素的形态测量法提取丘脑体积的估计值，并通过磁共振波谱法评估丘脑内 N-乙酰天冬氨酸/肌酸（NAA/cre）水平。探讨了丘脑体积与临床指标、定量感觉测试和神经病变表型之间的关系。
与健康参与者相比，糖尿病患者的灰质体积减少，包括双侧丘脑（所有 p 值均≤0.001）。丘脑体积估计值与丘脑内 NAA/cre 呈正相关（r=0.4；p=0.006），但与糖尿病病程（p=0.5）、DSPN 严重程度（p=0.7）或疼痛存在（p=0.3）无关。与丘脑体积最高的个体相比，丘脑体积最低的个体保护性感觉（使用类似冯·弗雷纤维的轻触觉，p=0.037）丧失最大，对电刺激的耐痛性（强直刺激，p=0.008）最高。
在这组 1 型糖尿病伴严重 DSPN 的患者中，存在丘脑萎缩，并与 NAA/cre 减少相关，提示丘脑结构丧失和功能障碍。丘脑萎缩与大纤维神经病和强直刺激感觉相关的感觉功能下降有关，这可能反映了突触传递。这可能最终有助于我们理解 DSPN 中明显的知觉变化背后的病理生理学。
