Vo Nhu Quynh, Hoang Ngoc Thanh, Nguyen Duy Duan, Nguyen Thi Hieu Dung, Le Trong Binh, Le Nghi Thanh Nhan, Nguyen Thanh Thao
Department of Radiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam.
Department of Internal Medicine, University of Medicine and Pharmacy, Hue University, Hue, Vietnam.
Quant Imaging Med Surg. 2022 Jun;12(6):3379-3390. doi: 10.21037/qims-21-910.
To explore the value of diffusion tensor imaging (DTI)-derived metrics in quantitative evaluation of carpal tunnel syndrome (CTS).
This prospective cross-sectional study included 39 wrists from 24 symptomatic CTS patients, who underwent clinical, electrophysiological, and magnetic resonance imaging (MRI) evaluations. In addition, 10 wrists of 6 healthy participants were included as controls. Clinical and nerve conduction study (NCS) findings were evaluated and graded according to the Boston Carpal Tunnel Questionnaire (BCTQ) and the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM), respectively. We performed MRI using a 1.5 Tesla scanner. Mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) of the median nerve at the distal radioulnar joint (DRUJ) (d), the inlet of the carpal tunnel (CT) at the pisiform level (i), the middle of the CT (m) and the outlet of the CT at the level of the hook of hamate (o), cross-sectional area at the inlet of the CT (iCSA), and the difference between MD and FA of the DRUJ and the outlet of CT (Delta MD and Delta FA) were measured.
The CTS patients had significantly lower FA [for example, oFA: mean difference 0.09, 95% confidence interval (CI): 0.05 to 0.12] and significantly higher MD than healthy participants (for example, iMD: mean difference 0.3, 95% CI: 0.03 to 0.57). There was a negative correlation between iCSA with iFA and between mFA and oFA (-0.5<R<-0.4). There was a positive correlation between distal motor latency time and Delta MD (R=0.57) and a negative correlation between distal motor latency time and Delta FA (R=-0.51). The FA demonstrated a somewhat strong negative correlation with the Boston scores for symptom and function.
The DTI-derived quantitative metrics add potential value to the evaluation of CTS. Alterations in the FA of the median nerve along the CT are the most significant features of CTS and reflect the degree of median nerve compression and clinical deficit. With a cutoff value of 0.45, FA at the carpal outlet has a sensitivity and specificity of 87.5% and 85.7% in the diagnosis of CTS, respectively.
探讨扩散张量成像（DTI）衍生指标在定量评估腕管综合征（CTS）中的价值。
这项前瞻性横断面研究纳入了24例有症状的CTS患者的39只手腕，这些患者接受了临床、电生理和磁共振成像（MRI）评估。此外，纳入了6名健康参与者的10只手腕作为对照。临床和神经传导研究（NCS）结果分别根据波士顿腕管问卷（BCTQ）和美国神经肌肉与电诊断医学协会（AANEM）进行评估和分级。我们使用1.5特斯拉扫描仪进行MRI检查。测量了尺桡远侧关节（DRUJ）（d）、豌豆骨水平腕管（CT）入口（i）、CT中部（m）和钩骨钩水平CT出口（o）处正中神经的平均扩散率（MD）、各向异性分数（FA）、轴向扩散率（AD）和径向扩散率（RD）、CT入口处的横截面积（iCSA）以及DRUJ和CT出口处MD与FA的差值（ΔMD和ΔFA）。
CTS患者的FA显著低于健康参与者（例如，oFA：平均差值0.09，95%置信区间（CI）：0.05至0.12），MD显著高于健康参与者（例如，iMD：平均差值0.3，95%CI：0.03至0.57）。iCSA与iFA之间以及mFA与oFA之间存在负相关（-0.5<R<-0.4）。远端运动潜伏期与ΔMD之间存在正相关（R=0.57），与ΔFA之间存在负相关（R=-0.51）。FA与波士顿症状和功能评分之间存在较强的负相关。
DTI衍生的定量指标为CTS的评估增添了潜在价值。沿腕管的正中神经FA改变是CTS的最显著特征，反映了正中神经受压程度和临床功能缺损程度。以0.45为临界值，腕管出口处的FA在CTS诊断中的敏感性和特异性分别为87.5%和85.7%。
