Long-Term In Vivo Evaluation of Chitosan Nerve Guide Properties with respect to Two Different Sterilization Methods

Figure 5

Histomorphometrical analysis of distal nerve ends compared to healthy nerve samples of age-correlated animals. In total cross sections, the cross-sectional area (a), the number of myelinated nerve fibers (b), and the nerve fiber density (c) have been evaluated at every time point (16, 36, 56, and 76 weeks; n=3). No significant differences were found between both groups while both significantly increased in nerve fiber density. Analysis of regeneration-related size parameters, i.e., g-ratio (d), axon diameter (e), fiber diameter (f), and myelin thickness (g), was performed at 56 and 76 weeks after surgery and revealed significant smaller fiber diameters and myelin thicknesses in both groups compared to healthy nerve specimen (n=3). Two-way ANOVA followed by Tukey’s multiple comparison was used for statistical analysis of the results (p<0.05, p<0.01, p<0.001 versus 16 weeks within the same group; <0.05, <0.01 versus 36 weeks within the same group; <0.05, <0.01, <0.001 versus healthy nerve at the same time). Results are displayed as median±range.

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