Aspectos morfométricos do nervo hipoglosso humano em adultos e idosos

• Main Author: Tiago, Romualdo Suzano Louzeiro [UNIFESP]
• Publication Date: 2005
• Other Authors: Faria, Flavio Paulo de [UNIFESP], Pontes, Paulo Augusto de Lima [UNIFESP], Brasil, Osíris de Oliveira Camponês do [UNIFESP]
• Format: Article
• Language: por
• Source: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300001hdwd
• Download full: http://dx.doi.org/10.1590/S0034-72992005000500002; http://repositorio.unifesp.br/handle/11600/2734
• topic: hypoglossal nerve; aging; dysphagia; nervo hipoglosso; envelhecimento; disfagia

AIM: Perform a morphometric analysis of the myelinic fibers of the right hypoglossal nerve, in two age groups; to verify quantitative changes as a result of the aging process. STUDY DESIGN: anatomic. MATERIAL AND METHOD: A 1cm fragment of the right hypoglossal nerve was collected from 12 male corpses without any medical history of diseases such as: diabetes, alcoholism, and malignant neoplasia. The sample was divided in two groups: group with six corpses under sixty years old (adult), and another group with six corpses sixty years old or above (elderly). The material was fixed at 2.5% glutaldehyde and 2% paraformaldehyde solution; post-fixed at 2% osmium tetroxide; dehydrated with increasing ethanol concentrations, and included in epoxy resin. Semi-thin sections of 0.3µm were obtaining, colored in 1% toluidine blue, and evaluated with light microscope combined with image analyzing system. The following morphometric data were quantified: intraperineural transversal section area, number, and diameter of the myelinic fibers. RESULTS: The intraperineural area of the hypoglossal nerve was similar in both age groups (p=0.8691). The average area in the adult group was 1.697mm² and in the elderly group it was 1.649mm². The total number of myelinic fibers of the hypoglossal nerve was similar in both age groups (p=0.9018). The adult group presented an average of 10,286 ± 2,308 myelinic fibers, and the elderly group presented an average of 10,141 ± 1,590 myelinic fibers. A bimodal distribution of the myelinic fibers was observed, with a significant peak on the 9µm fibers, and another smaller peak on the 2µm fibers. CONCLUSION: The intraperineural area and the total number of myelinic fibers of the right hypoglossal nerve are similar in both age groups.