Said G, Marion M H, Selva J, Jamet C
Neurology. 1986 Oct;36(10):1292-9. doi: 10.1212/wnl.36.10.1292.
Eight patients with Friedreich's ataxia showed profound reduction in the density of large myelinated fibers in sural nerve biopsies. The density of small myelinated fibers was normal, but the axonal size and myelin thickness were reduced. Demyelination, presumably secondary to axonal dysfunction, was observed in 3% of the isolated fibers. There was axonal degeneration, including dying-back axons isolated in three specimens, in 2.6% of the isolated fibers. The low incidence of degenerating fibers did not account for loss of myelinated fibers in children. There is probably a defect in maturation of fibers, followed by a dying-back process.
8例弗里德赖希共济失调患者的腓肠神经活检显示，有髓大纤维密度显著降低。有髓小纤维密度正常，但轴突大小和髓鞘厚度减小。在3%的单个纤维中观察到脱髓鞘，推测这是继发于轴突功能障碍。在2.6%的单个纤维中存在轴突变性，包括在三个标本中分离出的逆行性轴突。变性纤维的低发生率并不能解释儿童有髓纤维的丢失。可能存在纤维成熟缺陷，随后是逆行性病变过程。
