Use of pyrolytic carbon coated beads (Durasphere) to treat glottic failure: an experimental study in dogs.
There is no ideal tissue or substance to be injected in the vocal folds. The objective of the present study was to assess the use of Durasphere in canine vocal fold injection.


METHODS
in six adult dogs we injected 0.3 mL of Durasphere in the middle third of the thyroarytenoid muscle and 0.3 mL of saline solution in the contralateral vocal fold. The animals were slaughtered after seven days (three dogs) and after 90 days (three dogs). We analyzed the inflammatory process in the vocal fold and in the lamina propria of the vocal folds.


RESULTS
in the vocal muscle which received Durasphere there was a significantly more intense inflammation when compared to the control muscle--there was a moderate lymphomodular infiltrate after seven days and mild after 90 days. We did not observe foreign bodies nor granulomas. On the lamina propria there was a mild inflammatory process in the two groups, without difference between them.


CONCLUSIONS
this is a substance of proven biocompatibility in humans, with preliminary and unprecedented results and its injection in canine vocal folds caused a moderate inflammatory process after seven days and mild after 90 days, without foreign bodies or granuloma formation.
Tsuji
Domingos Hiroshi
DH
Larynx Group, University of Sao Paulo Medical School.
Sakae
Flavio Akira
FA
Imamura
Rui
R
Ferraz
Luis Fernando
LF
Sennes
Luiz Ubirajara
LU
D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage*; D004285:Dogs; D005260:Female; D005936:Glucans / Q000008:administration & dosage*; D007827:Laryngitis / Q000139:chemically induced / Q000473:pathology; D008297:Male; D013997:Time Factors; D014827:Vocal Cords / Q000187:drug effects* / Q000473:pathology; D015040:Zirconium / Q000008:administration & dosage*
D001672:Biocompatible Materials; D005936:Glucans; C431745:durasphere; D015040:Zirconium