Lucy and the BEMS
Lucy is a 1 year old female, spayed Havanese. She was spayed and had an exploratory to rule out a portosystemic shunt. The next day after release she developed signs of nasal obstruction, wheezing and rattling with some clear nasal discharge. On examination, stridor was present, appearing to come from the nose/nasopharynx, on both inspiration and expiration. The history and signs suggested that she had acquired nasopharyngeal stenosis probably from post operative regurgitation of stomach contents into her nose. She was scheduled for combined MRI of the skull, rhinoscopy and nasopharyngoscopy. The MRI demonstrated some aqueous material in the caudal nares and an area of stenosis above the caudal hard and rostral soft palate. Retroflex nasopharyngoscopy provided good images of the stenosis after mucus was flushed with saline and aspirated from the site. A 2 mm biopsy forceps could not be passed retrograde from the nasopharynx through the stenotic area. The MRI images were used to measure an appropriate stent size to open the stenotic lesion. A 17mm x 8 mm Balloon Expandable Metallic Stent (BEMS) was ordered for Lucy and placement scheduled for a second procedure. After induction of anesthesia, Lucy was placed under the fluoroscope and the bronchoscope was retroflexed into the nasopharynx. A weasel wire could not be successfully placed antegrade from the nose through the stent with fluoroscopic guidance so the wire was passed retrograde via endoscopic guidance through the stent. The guidewire was used to pass 5 Fr then 6 Fr then 8 Fr vascular dilators thru the stent to allow passage of the BEMS. A 1 cm x 4 cm vascular balloon dilator was placed across the stenotic lesion and the balloon inflated under endoscopic guidance. A moderate amount of hemorrhage occurred when this was accomplished. After the bleeding was controlled, the BEMS was placed across the stenotic area then inflated to the recommended pressure. The balloon was then deflated and the stent appeared to be in proper position. Remaining mucus and blood was aspirated and a post operative radiograph was taken. Immediately post op, a small amount of stertor was present when the Lucy became excited. Lucy was reevaluated one week later and the stridor had resolved. Lucy could now sleep normally and returned to sniffing things outside as was her normal behavior. Berent et. al. reported on 6 dogs and cats in JAVMA Vol. 233, No. 9 in November 2008 with nasopharyngeal stenosis treated successfully with this method. The balloon expandable metallic stent is used because it simultaneously dilates the stenosis and places the stent. Self expanding stents will not work because the do not have the radial force to dilated an area of scar tissue. One of the lessons we all can learn from Lucy is that when animals regurgitate/vomit in the perioperative period, flush their noses copiously with sterile saline to remove and stomach contents from the nasal cavity.