Danish Pain Research Center, Aarhus University Hospital, Aarhus, Denmark.
J Neuropathol Exp Neurol. 2013 Mar;72(3):186-93. doi: 10.1097/NEN.0b013e318284e849.
Assessment of intraepidermal nerve fiber density (IENFD) has become a useful tool for the investigation of patients with suspected small-fiber neuropathy (SFN). Here, we estimate epidermal nerve fiber lengths in 12 patients with SFN and 36 healthy controls using global spatial sampling and compare the lengths with IENFD and axonal swelling ratios. Skin biopsies were analyzed on 50-μm-thick free-floating sections immunostained for the neuronal cytoplasmic marker PGP 9.5. Mean IENFD in SFN patients was 2.22 ± 1.63 mm versus 7.51 ± 2.17 mm in controls; mean length density was 112 ± 82.6 mm in SFN patients versus 565 ± 240 mm in controls (p < 0.001 for both). The correlation between the nerve fiber length and the IENFD was r = 0.16 for healthy subjects and r = 0.39 for patients, suggesting that these variables provide different quantitative information. There were significant differences in axonal swelling ratios between healthy subjects and patients, that is, per IENFD and per nerve fiber length. Together, these results suggest that, although length estimation requires more time and additional equipment, it is as effective as IENFD in differentiating SFN patients from healthy subjects. Estimating nerve fiber length may increase mechanistic understanding beyond IENFD estimation and improve efficiency in diagnosing SFN.
表皮内神经纤维密度（IENFD）的评估已成为研究疑似小纤维神经病（SFN）患者的有用工具。在这里，我们使用全局空间采样来估计 12 名 SFN 患者和 36 名健康对照者的表皮神经纤维长度，并将这些长度与 IENFD 和轴突肿胀比进行比较。皮肤活检在 50μm 厚的游离漂浮切片上进行，免疫组化染色用于神经元细胞质标志物 PGP 9.5。SFN 患者的平均 IENFD 为 2.22±1.63mm，对照组为 7.51±2.17mm；SFN 患者的平均长度密度为 112±82.6mm，对照组为 565±240mm（均 p<0.001）。健康受试者的神经纤维长度与 IENFD 之间的相关性为 r=0.16，患者的相关性为 r=0.39，这表明这些变量提供了不同的定量信息。健康受试者和患者之间的轴突肿胀比存在显著差异，即每 IENFD 和每神经纤维长度。总之，这些结果表明，尽管长度估计需要更多的时间和额外的设备，但它与 IENFD 一样有效地将 SFN 患者与健康受试者区分开来。估计神经纤维长度可能会增加对 IENFD 估计之外的机制理解，并提高 SFN 的诊断效率。
