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CC BY-NC-ND 4.0 · Journal of Morphological Sciences 2018; 35(01): 25-27
DOI: 10.1055/s-0038-1660484
Original Article
Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil

Degree of Myelination (g-ratio) of the Human Hypoglossal Nerve

D. Campos
1   Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil
2   Departamento de Biologia e Farmácia, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, RS, Brazil
,
J.N. Páfaro
1   Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil
,
G.R. Goulart
2   Departamento de Biologia e Farmácia, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, RS, Brazil
,
C.H. Silveira
2   Departamento de Biologia e Farmácia, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, RS, Brazil
,
P.A.M. Cella
1   Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil
,
T. Malysz
3   Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
4   Programa de Pós-graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
,
G.P. Jotz
3   Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
5   Programa de Pós-graduação em Ciências da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil
› Author Affiliations
Further Information

Publication History

13 March 2017

28 February 2018

Publication Date:
14 June 2018 (online)

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Abstract

Introduction The degree of myelination (g-ratio) can be useful to the evaluation of the fiber morphology during peripheral nerve regeneration and in studies in the area of microsurgery. Therefore, the aim of this analyze was to investigate the g-ratio of the human hypoglossal nerve.

Materials and Methods The hypoglossal nerve was bilaterally analyzed in human specimens obtained from necropsies (6 subjects). The nerves were analyzed using histology, and the morphometric parameters (axon diameter and myelinated fiber diameter) were measured using Image Pro-Plus Software 6.0.

Results Quantitative comparison of the g-ratio demonstrated no statistically significant difference between the left and right human hypoglossal nerves. In addition, the values of the g-ratio of both hypoglossal nerves were considerably higher than the normal values for the peripheral nerve fibers. This demonstrates a low degree of myelination of the hypoglossal nerve, bilaterally.

Conclusion Knowledge of the variations of the human hypoglossal nerve, are clinically important especially in the area of microsurgery (techniques used for reinnervation).

Keywords

hypoglossal nerve - g-ratio - axon diameter - myelinated fiber diameter - human
 

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