In this study, we developed a rat model for
Teflon granuloma and used this model to evaluate the removal of the
granuloma at
laser wavelengths at which
Teflon has a maximal absorption. Twenty-four
Teflon granulomas were created in 12 rats, and the gross and histologic effects from
laser incision at four different wavelengths (8.25, 8.5, 8.75, and 10.6 microm) were evaluated acutely and at 7 and 14 days postoperatively.
Polytetrafluoroethylene, or
Teflon, is a relatively inert substance that has been used over the past 4 decades for endoscopic injection into the thyroarytenoid muscle of the larynx for the purposes of laryngeal rehabilitation in cases of unilateral vocal fold
paralysis or incomplete glottic closure. In certain cases in which formation of granulomatous reaction to the
Teflon occurs, patients may have significant
dysphonia or airway compromise. Once
Teflon has infiltrated the surrounding tissue planes, it is exceedingly difficult to remove endoscopically. Endoscopic removal of this
granuloma is usually attempted with the
carbon dioxide (
CO2) laser and has had limited success. Examination of the infrared absorption spectrum of
polytetrafluoroethylene reveals strong absorption in the mid-infrared region in the 8- to 9-microm range, with minimal absorption at 10.6 microm. Therefore, this absorption spectrum predicts a more efficient vaporization of
Teflon at wavelengths near 8.5 microm. Using the free-electron
laser to generate 8.25-, 8.5-, and 8.75-microm
laser light, we found
Teflon granuloma ablation was far superior to
CO2 laser ablation at 10.6 microm. The 8.25-, 8.5-, and 8.75-microm wavelengths selectively ablated
Teflon granuloma with minimal to no collateral thermal injury to tissue. The differences in thermal effects observed while actually using the
lasers were confirmed histologically.