[Histopathological change of cricoarytenoid joint after laryngeal recurrent nerve paralysis in dogs].

OBJECTIVE

To investigate the histopathological changes in cricoarytenoid joints in 32 animal models. The characteristic histopathological changes of arytenoid cartilages after recurrent nerve paralysis were evaluated.

METHODS

Sixteen dogs (32 vocal folds, 8 as normal control) were divided into different animal models of recurrent nerve paralysis as transection, half-section, ligation, or crush. The histopathological finds of arytenoid cartilages were analysed.

RESULTS

Arytenoid cartilages showed fibrin (12/24), disruption of the fibrous membrane (9/24), fibrillation (7/24) and degenerative changes in their joint surface structure (3/24) at various levels of intensity. The fibrin and disruption of the fibrous membrane were found 1 month after injury, and all changes appeared in 6 months. The fibrillation and arytenoid cartilages degenerative changes revealed in transaction group and ligation group, and became stronger in time of 6 months. The correlation among the fibrillation ratio and the normal control was positive (t were 6.23 and 3.65, P < 0.01). The correlation among the number of cellular of arytenoid cartilages and the normal control was positive (t = 2.78, P < 0.05). The fibrillation (7) and arytenoid cartilages degenerative changes (3) revealed in vocal fold fixation to influence the recovery of laryngeal function.

CONCLUSIONS

The histopathological change of cricoarytenoid joint after recurrent nerve paralysis was related to the severity of neural injury. Influence the recovery of laryngeal function more often from 6 months.