[Pathologic changes of palatopharyngeal muscle in patients with obstructive sleep apnea hypopnea syndrome].

Objective: To study the pathologic changes of the palatopharyngeal muscles in patients with obstructive sleep apnea hypopnea syndrome (OSAHS), the role of the above muscles in OSAHS pathogenesis was discussed.
Methods: Thirty OSAHS patients receiving uvulopalatopharyngoplasty selected, and ten normal subjects without snoring as the control group. The successive longitudinal sections of palatopharyngeal muscle were stained for observing Troponin-I's content. All specimens were examined with transmission electronmicroscopy (TEM) and light microscopy.
Results: Twenty nine of 30 specimens obtained from OSAHS patients evaluated with TEM showed pathologic changes of different degrees. While 2 among 10 specimens in control group showed mild myofibril edema or hypertrophy, no pathologic changes shown in other specimens. Immunohistochemistrial results of all specimens sections stained for observing Troponin-I antibody have shown that negative grey degree value is 146.30 +/- 10.72 in study group and 107.50 +/- 4.81 in control group respectively. There is significant difference between these two groups (P < 0.05). The negative grey degree value of study groupl and study group2 are 143.12 and 148.80 respectively , no statistical difference (P > 0.05).
Conclusions: Palatopharyngeal myelofibrosis may affect pharyngeal dilator muscles function, this could be one mechanism of upper airway collapsibility.