Description and evaluation of a novel transoral endoscopic arytenopexy in canine cadavers

OBJECTIVE

To describe the transoral endoscopic arytenopexy (TEA) and evaluate its effects on the rima glottis area (RGA) and laryngeal epiglottic-glottic seal (LEGS). We hypothesize the TEA will be a feasible surgical technique and the TEA will provide a significant increase in RGA with minimal change to the LEGS.

STUDY DESIGN

Canine cadaveric model.

ANIMALS

Fifteen medium- to large-breed canine cadavers.

METHODS

Endoscopic photos of the larynx were taken with the epiglottis open for baseline RGA measurement and closed for baseline measurement of exposed RGA and LEGS. A custom endoscopic gag port (EGP) facilitated the TEA, performed by suturing the lateral aspect of the left arytenoid soft tissues to adjacent pharyngeal wall across the piriform recess. Endoscopic photos were repeated to measure changes in RGA and LEGS. A computerized planimetric analysis program was used to calculate baseline RGA and LEGS. The RGA was reported in % change from baseline. The LEGS was reported as intact or altered. A nonparametric Wilcoxon signed-rank test was used to compare baseline to post-TEA RGA.

RESULTS

The mean baseline RGA was 0.52 ± 0.28 cm³ and mean post-TEA RGA was 0.78 ± 0.37 cm³ (p-value < .0001). The LEGS remained intact post-TEA in all cadavers.

CONCLUSIONS

The TEA was technically feasible and resulted in an increase in RGA while maintaining the LEGS.

CLINICAL SIGNIFICANCE

The TEA may provide a minimally invasive addition to the established techniques for reducing airway resistance while minimizing the impact on the LEGS.

Comparison of immediate and short-term outcomes of cricoarytenoid and thyroarytenoid lateralization in dogs with idiopathic laryngeal paralysis

OBJECTIVE

To compare the immediate and short-term outcomes of thyroarytenoid lateralization (TAL) and cricoarytenoid lateralization (CAL) for the treatment of canine laryngeal paralysis in dogs.

STUDY DESIGN

A prospective, clinical trial.

ANIMALS

Fourteen client-owned dogs referred to our hospital because of bilateral laryngeal paralysis.

METHODS

Dogs with confirmed laryngeal paralysis were randomly assigned to the CAL or TAL group. Video images of the rima glottidis obtained preoperatively, immediately postoperatively (t0), and 15 days postoperatively (t1) were digitized. The rima glottidis area was measured using image-analysis software. An increase in the rima glottidis area was expressed as a percentage of the preoperative area.

RESULTS

The rima glottidis area increased by a mean of 152% at t0 and 127% at t1 for the TAL group and 205% at t0 and 199% at t1 for the CAL group compared with preoperative values. The increase in the rima glottidis area differed (P < .05) between the 2 groups at all postoperative time points. A reduction of the area occurred at t1 in both groups. There was no difference between t0 and t1 (P > .05) in the CAL group but there was a large difference (P < .05) in the TAL group.

CONCLUSION

Cricoarytenoid lateralization and TAL were both effective for surgical abduction of the arytenoid cartilage. Although a reduction (P < .05) in the rima glottidis area occurred in the TAL group at t1, we observed no associated clinical signs.

CLINICAL SIGNIFICANCE

Cricoarytenoid lateralization and TAL result in good short-term outcomes in dogs with laryngeal paralysis.

Laryngeal Disease in Dogs and Cats: An Update

Laryngeal diseases are manifested by obstructive breathing patterns reflecting functional or mechanical upper airway obstruction. Laryngeal paralysis is the most common disease of the larynx. Diagnosis requires close attention to anesthetic plane and coordination of respiratory effort with laryngeal motion. Surgical arytenoid lateralization improves clinical signs and quality of life in dogs; however, aspiration pneumonia is a recognized complication, and generalized neuropathy can progress. Laryngeal collapse can result from any cause of chronic upper airway obstruction but is most often associated with brachycephalic obstructive airway syndrome. Although uncommon, laryngeal neoplasia has a guarded to grave prognosis regardless of treatment.