Liampas Ioannis, Veltsista Dimitra, Germeni Alexandra, Batzikosta Paraskevi, Michou Emilia, Kefalopoulou Zinovia, Chroni Elisabeth
Department of Neurology, University Hospital of Patras, School of Medicine, University of Patras, Patras, Rio 26504, Greece; Department of Neurology, University Hospital of Larissa, School of Medicine, University of Thessaly, Larissa 41100, Greece.
Department of Neurology, University Hospital of Patras, School of Medicine, University of Patras, Patras, Rio 26504, Greece.
Neurophysiol Clin. 2025 Aug;55(4):103061. doi: 10.1016/j.neucli.2025.103061. Epub 2025 Mar 13.
This systematic review and meta-analysis aimed to determine the pattern of F-wave abnormalities and their potential utility in the early diagnosis of amyotrophic lateral sclerosis (ALS).
Medline and Embase were thoroughly searched. We primarily emphasized F-wave recordings from the abductor digiti minimi, following stimulation of the ulnar nerve at the wrist. Data from case-control studies involving individuals with ALS versus healthy controls (HC) or other well-defined patient groups were reviewed and -if appropriate- quantitatively synthesized.
Twenty-nine studies were included in this systematic review and 17 of them in the analytic part. The pattern of F-abnormalities in ALS compared to HC was as follows: decreased persistence (MD=20.25 %,15.67-24.84 %), mildly prolonged minimum latency (MD=1.59msec,1.11-2.06msec), increased maximum amplitude (MD=196μV,106-287μV) and elevated Index total Freps (MD=33.9 %,26.0-41.8 %). Affected limbs (with substantial weakness in clinical examination and/or muscle wasting and/or abnormal nerve conduction studies) exhibited more marked abnormalities in persistence, minimum latency, and Index total Freps, whereas abnormalities in these parameters were very mild in clinically unaffected limbs. More prominent increases in maximum amplitude accompanied pyramidal dysfunction. Of note, isolated upper motor neuron (UMN) disorders exhibited a comparable increase in Index total Freps without a decrease in persistence.
The pattern of F wave abnormalities may raise suspicion of involvement of the under-study lower motor neuron (LMN) pool in ALS. These findings may identify LMN dysfunction even at a preclinical stage and prompt extensive electromyographic investigations. UMN involvement may to some extent differentiate the profile of F wave abnormalities in ALS.
本系统评价和荟萃分析旨在确定F波异常模式及其在肌萎缩侧索硬化症（ALS）早期诊断中的潜在效用。
全面检索了Medline和Embase数据库。我们主要关注在腕部刺激尺神经后，从小指展肌记录的F波。对涉及ALS患者与健康对照（HC）或其他明确界定的患者组的病例对照研究数据进行了回顾，并在适当情况下进行了定量综合分析。
本系统评价纳入了29项研究，其中17项纳入了分析部分。与HC相比，ALS患者的F波异常模式如下：持续时间降低（MD = 20.25%，15.67 - 24.84%），最小潜伏期轻度延长（MD = 1.59毫秒，1.11 - 2.06毫秒），最大波幅增加（MD = 196微伏，106 - 287微伏）以及总F波重复率指数升高（MD = 33.9%，26.0 - 41.8%）。受累肢体（在临床检查中有明显无力和/或肌肉萎缩和/或神经传导研究异常）在持续时间、最小潜伏期和总F波重复率指数方面表现出更明显的异常，而在临床未受累肢体中，这些参数的异常非常轻微。最大波幅更显著的增加与锥体束功能障碍相关。值得注意的是，孤立的上运动神经元（UMN）疾病在总F波重复率指数上有类似的升高，但持续时间没有降低。
F波异常模式可能会引发对ALS中所研究的下运动神经元（LMN）池受累的怀疑。这些发现可能在临床前期阶段就能识别出LMN功能障碍，并促使进行广泛的肌电图检查。UMN受累在一定程度上可能会区分ALS中F波异常的特征。
