The Morphology Observation of Posterior Cricoarytenoid Muscle Myofiber in Patients with Idiopathic Vocal Fold Paralysis / 听力学及言语疾病杂志

ABSTRACT

Objective To investigate the morphology change of posterior cricoarytenoid muscle myofiber in patients with idiopathic vocal fold paralysis and to provide experimental evidence for the clinical treatment of idio‐pathic vocal cord paralysis .Methods Thirty -nine cases of vocal fold paralysis patients were recruited into and di‐vided into 2 groupsidiopathic vocal cord paralysis group(n=16) ,and traumatic vocal cord paralysis group(n=23) . Both groups were further divided into 3 subgroups0 .5~1 year(5 cases and 7 cases) ,>1~2 years(5 cases and 10 cases) ,>2 years(6 cases and 6 cases) .Part of posterior cricoarytenoid muscle(PCAM ) were acquired from all of vo‐cal cord paralysis patients .Normal human posterior cricoarytenoid muscles were treated as the control group (n=5) . They were all stained with Masson three-color staining ,the fiber crosssectional area of muscle tissue and collagen connective tissue were quantitatively analyzed with the image pro plus analysis system .Differences of two observa‐tion indexes were compared with each other among groups and subgroups .Results The number of myofibers was decreased ,but the numbers of the collagen fibers was increased with the onset time course extension ,the ratio of cross sectional area of myofibers to those of collagen fibers was progressively decreasd with increased time course of denervation and more decrease within 1 year .There was obvious difference between the control group and 0 .5~1 year ,>1~2 years ,>2 years subgroup of idiopathic vocal cord paralysis (P1~2 years subgroup and >2 years subgroup ,the trend of shrinking still existed .Com‐pared two observation indexes of traumatic vocal cord paralysis with the same period subgroup indexes of idiopathic vocal fold paralysis ,there was no significant difference about these two observation indexes (P>0 .05) .In some special cases with 10 years duration in idiopathic vocal cord paralysis group ,the posterior cricoarytenoid muscle at‐rophy fibrosis was not serious .However ,in some case which the course lasted for only 1 .5 years ,the muscle atrophy was very obvious .There were great individual differences among idiopathic vocal cord paralysis patients .Conclusion If there is no recovery after half year treatment ,for PCA muscle function recovery ,the recurrent laryngeal nerve injury repair surgery could be considered to carry out within 1 year .In some cases with long disease duration (>2 years) ,they may still have the muscle morphological basis for nerve repair .