Hyoepiglottic ligament collagen and elastin fiber composition and changes associated with aging.

OBJECTIVE

The epiglottis may contribute to upper airway obstruction in approximately 10% of patients with obstructive sleep apnea. Clinical experience indicates that older patients may be more likely to have epiglottis-related obstruction. This study was designed to examine tissue characteristics of the hyoepiglottic ligament as a possible factor in epiglottis-related obstruction based on previous research suggesting that older adults have fewer collagen, elastin, and muscle fibers in the hyoepiglottic ligament.

METHODS

This is a cross-sectional study of 25 human cadaver hyoepiglottic ligaments. Specimens were stained using Masson's trichrome and Picrosirius red for collagen fibers and with Verhoeff-Van Gieson for elastin fibers. Percentage of collagen and elastin fiber staining for each specimen was calculated and averaged over three regions of each ligament section. Regression analysis was used to determine the association between age, smoking history, and collagen and elastin composition of the hyoepiglottic ligament.

RESULTS

The average age of the specimens was 68.4 ± 15.1 years (range 30-90 years). Increasing age was associated with a lower percentage of collagen and elastin fibers. When accounting for tobacco use, each 1-year increase in age was associated with a 0.53% decrease in Masson's trichrome staining (P = 0.004), a 0.35% decrease in Picrosirius red staining (P = 0.023), and a 0.33% decrease in Verhoeff-Van Gieson staining (P = 0.008).

CONCLUSION

Increasing age is associated with decreases in the collagen and elastin content of the hyoepiglottic ligament.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:1245-1248, 2018.