Effects of Arytenoid Abduction and Modified Castellated Laryngofissure on the Rima Glottidis in Canine Cadavers

Abstract

The percentages of change in cross-sectional area and dorsoventral height of the rima glottidis were measured after seven types of laryngoplasty in 30 postmortem canine specimens. The mean increases in area after each procedure were, in decreasing order, bilateral cricoarytenoid disarticulation with interarytenoid sesamoid band transection before placement of arytenoid abduction sutures 350% +/- 42%, bilateral placement of arytenoid abduction sutures 318% +/- 40%, bilateral cricothyroid disarticulation before placement of arytenoid abduction sutures 255% +/- 51%, modified castellated laryngofissure 244% +/- 30%, unilateral cricoarytenoid disarticulation with interarytenoid sesamoid band transection before placement of an arytenoid abduction suture 161% +/- 25%, unilateral placement of an arytenoid abduction suture 151% +/- 24% and unilateral cricothyroid disarticulation before placement of an arytenoid abduction suture 108% +/- 25%. Bilateral cricoarytenoid disarticulation with interarytenoid sesamoid band transection before placement of arytenoid abduction sutures resulted in a significantly greater increase in rima glottidis area than modified castellated laryngofissure and all unilateral arytenoid abduction techniques. Modified castellated laryngofissure resulted in a significantly greater increase than unilateral placement of an arytenoid abduction suture and cricothyroid disarticulation before placement of an arytenoid abduction suture. Bilateral disarticulation of the cricothyroid joint before placement of arytenoid abduction sutures resulted in significant collapse of the dorsoventral height of the rima glottidis.

The Effect of Two Modifications of Unilateral Arytenoid Lateralization on Rima Glottidis Area in Dogs

“…Compared with previous studies in young, healthy cadaver dogs, we obtained a greater increase in rima glottidis area with live anesthetized dogs affected with laryngeal paralysis. In previous cadaver studies, increases in rima glottidis area of 108% and 136% for TAL and 161%–192% for CAL have been reported 14,15 . In our study, CAL and CTAL resulted in mean increases of 241.5% and 236.4%, respectively.…”

“…Unilateral arytenoid lateralization is an effective procedure for the alleviation of laryngeal paralysis in dogs. The effects of modifying unilateral arytenoid lateralization on increasing rima glottidis area have been examined in 3 studies using excised larynges from recently euthanatized adult dogs 13–15 . Use of an excised larynx model without innervation, no vascular supply, and no surrounding tissue support, may contribute limitations when assessing increases in rima glottidis area after arytenoid lateralization.…”

“…The effects of not disarticulating the cricothyroid joint or transecting the interarytenoid sesamoid band were not evaluated in our study. In an in vitro study, disarticulation of the cricothyroid joint resulted in disruption of the lateral support of the larynx, leading to an inclination for the rima glottidis to collapse dorsoventrally 14 . This observation may be related to the fact that the excised larynges lacked external support to prevent collapse.…”

“…Cricothyroid and cricoarytenoid disarticulation plus transection of the interarytenoid sesamoid band are described for both CAL and TAL. The relative increase in rima glottidis area achieved with these techniques in both live anesthetized dogs clinically affected with bilateral laryngeal paralysis and in normal canine cadaver larynges have been reported 13–16 . CAL results in a significantly greater increase in rima glottidis area than TAL 16 .…”

A Comparison of the Effects of Unilateral Thyroarytenoid Lateralization Versus Cricoarytenoid Laryngoplasty on the Area of the Rima Glottidis and Clinical Outcome in Dogs with Laryngeal Paralysis

“…15 A number of techniques have been used to assess the clinical or anatomic outcome of surgical procedures for the treatment of laryngeal paralysis in dogs, including tidal breathing loops, blood gas analysis, and cadaver studies. 2,[19][20][21][22] The aim of this study was to define the clinical response to two commonly used surgical procedures that have been reported to result in significantly different increases in the area of the rima glottidis. 19 …”