Fig. 3. (First row ) Subglottic views of canine vocal folds. Note the inner vestibular (barking) folds. (Second row ) (Left ) Canine vocal folds seen from within the trachea. (Right ) A few seconds later, advancement of the endotracheal tube through the same canine vocal folds under direct miniendoscope visualization. (Third row ) (Left ) Tracheal rings in the canine trachea (caudad view). (Right ) The lighted end of the miniendoscope protrudes through the canine vocal folds (laryngoscopic view).