Introduction

Laryngeal collapse is a recognised component of the brachycephalic obstructive airway syndrome (BOAS) and is identified by visual inspection during light anaesthesia.

Objectives

To validate the use of echolaryngography in the identification of laryngeal collapse in the unsedated animal.

Methods

Thirty-three (33) brachycephalic dogs presented at the QVSH for the investigation of BOAS with echolaryngography and visual inspection of the larynx as a component of the workup.

Echolaryngography was performed with the larger dogs sitting either on the floor or on a table. The smaller breeds were examined on the lap of the ultrasonographer to minimise stress and panting. A 15 MHz linear probe was placed over the larynx. Care was taken not to apply excessive pressure on the larynx. The vocal folds, rima glottidis and cuneiform processes were identified.

According to the visual inspection, the animals were divided into the stages of collapse described in the literature: 0 = no collapse, 1 = everted sacculi, 2 = medial displacement of cuneiform processes, 3 = collapse of corniculate processes. On echolaryngography 2 groups were identified N = no collapse and C = collapse.

Results

The breeds examined were 14 pugs, 14 French bulldogs, 5 English bulldogs. During echolaryngography the vocal cords, cuneiform processes, and rima glottides were identified in the unsedated animal as described in the literature. Laryngeal sacculi could not be identified on echolaryngography thus group N consists of both stages 0 and 1.

Table 1. Results of echolaryngography and visual inspection

Conclusions

A good correlation of 97% between echolaryngography and visual inspections was found.