Many performance horses work with their heads and necks flexed ventrally, which, while desirable in some disciplines, can either cause or exacerbate an upper airway obstruction. Fortunately, researchers recently tested a surgical procedure designed to provide relief for horses suffering from such obstructions—caused by collapse of a region of the throat called the nasopharynx—with positive results.

“Any sort of obstruction of the upper airway, such as that can be induced by ventral neck flexion, can result in (poor performance) and abnormal respiratory noise,” explained Ann Kristin Barton, DVM, Dipl. ECEIM, of the Free University of Berlin University of Veterinary Medicine and Equine Clinic, in Germany.

Another consequence of upper airway obstruction is that air can get trapped inside the guttural pouches, which are air-filled structures located high within the skull separated by a thin membrane. And, Barton noted, if air becomes trapped in the guttural pouch, increased pressure within the structures develops, likely contributing to nasopharyngeal collapse.

Because there is no effective reported treatment for correcting dynamic nasopharyngeal collapse, Barton and colleagues recently tested a surgical technique designed to relieve collapse. Barton used a laser passed through the nasal passages to create a "window" in the membrane between the two guttural pouches and remove one of the pouches' opening flaps, which is primarily responsible for trapping air. The researchers tested the procedure on nine horses with a history of poor performance and respiratory noise