Endoscope-guided balloon sinuplasty of the equine nasomaxillary opening.

OBJECTIVE To describe and evaluate an endoscope-guided balloon sinuplasty technique for dilation of the equine nasomaxillary opening (NMO). STUDY DESIGN Experimental study. ANIMALS Equine cadaver heads (n=5); Quarter Horses (n=4). METHODS A custom rigid balloon introducer was passed into position within the NMO at the caudal recess of the middle meatus. Under endoscopic guidance, a balloon catheter was passed via the introducer into the NMO and inflated to 6 atmospheres, for 30 seconds 3 times, to dilate the NMO. Drainage rates after sinuplasty were evaluated for the caudal maxillary sinus in 5 cadaver heads and balloon sinuplasty was performed in 4 live horses. All skulls were examined to assess the efficacy of NMO dilation. RESULTS Positioning of the balloon catheter was readily achieved in all heads. Dilation was observed endoscopically and confirmed on necropsy in all heads. Drainage rates from the caudal maxillary sinus increased significantly (approximately 1.5 x) in all 5 cadaver heads after sinuplasty (P=.001). CONCLUSIONS Dilation of the NMO improved sinus drainage in all 5 cadaver heads. Endoscopic evaluation of the ostium revealed marked dilation of the NMO in live horses and indicates potential clinical use in standing horses. CLINICAL RELEVANCE Balloon sinuplasty of the NMO opening is an easily performed, clinically applicable technique for use in standing horses. Clinical studies will be necessary to evaluate the efficacy of this technique in diseased sinuses.