Article

Treatment of vocal fold scarring: rheological and histological measures of homologous collagen matrix.

Department of Surgery, University of Wisconsin-Madison, 53792-7375, USA.
The Annals of otology, rhinology, and laryngology (impact factor: 1.05). 11/2002; 111(10):884-9. pp.884-9
Source: PubMed

ABSTRACT The current treatment options for dysphonia secondary to vocal fold scarring are limited. Few studies address changes in the lamina propria, which is critical to vocal fold biomechanical properties and voice production. Using rheological and histological measures of homologous collagen matrix (HCM)-injected vocal folds, we assessed HCM's potential for providing bulk and restoring biomechanical performance. Twenty rabbits underwent bilateral vocal fold scarring. After 10 weeks of scar maturation, the rabbits had unilateral injections of HCM or saline solution. Ten weeks after the injections, histological studies revealed well-defined collagen globules distributed throughout the lamina propria and underlying muscular tissue. Significantly more procollagen was observed in the HCM-treated group. No significant differences in elastic shear modulus or dynamic viscosity were found between the treatment groups. This study demonstrates that HCM is an inert, relatively stable injectate that may serve well for medialization but does not appear to improve the dynamic properties of the lamina propria.

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    Eric Goodyer, Heather Gunter, Asa Masaki, James B Kobler, Harris, Peyton Mosher
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    David Greco Varela, Marcos Grellet
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Keywords

bilateral vocal
 
biomechanical performance
 
critical
 
current treatment options
 
elastic shear modulus
 
HCM's potential
 
HCM)-injected vocal folds
 
HCM-treated group
 
homologous collagen matrix
 
injections
 
lamina propria
 
muscular tissue
 
procollagen
 
rheological
 
saline solution
 
stable injectate
 
studies address changes
 
vocal
 
voice production
 
well-defined collagen globules