to the epiglottis. This causes partial obstruction of the lumen of the airway, which reduced the inspiratory volume, causes turbulent airflow, and increases the resistance of airflow in the distal airways. Horses with congenitally hypoplastic epiglottises or soft palates and those suffering from upper respiratory tract infections are predisposed for dorsal displacement of the soft palate. Horses that exercise with the head and those who pull on the bit are also have an increased risk of developing dorsal displacement of the soft palate. The clinical presentation of dorsal displacement of the soft palate includes expiratory stridor during exercise, exercise intolerance, poor performance and due to hypoxia when exercising intensely. Diagnosis is made through endoscopy revealing the dorsal displacement of the soft palate. Dynamic endoscopy may be required for diagnosis as the palate may only become displaced during intense exercise or when bit pressure is applied. Treatment includes tying the tongue during exercise to prevent caudal pressure on the soft palate, the use of “ ” or other apparatuses that resist caudal pressure on the soft palate, or the surgical remodelling of the soft palate.
Prognosis is guarded.
Guttural Pouch Diseases
The guttural pouch is an enlarged sac that extends off of the
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The function of the guttural pouch is unknown, but it may be involved in the thermoregulation of the brain and the regulation of between the inner ear and the respiratory tract. Many important structures are associated with the guttural pouch. Cranial nerves VII, IX, X, XI and XII pass either adjacent to or through the guttural pouch, the cervical sympathetic trunk and the cranial cervical ganglion are located in close proximity to the guttural pouch, and the internal and external arteries pass within the guttural pouch. Any condition affecting the guttural pouch will have an effect on the integrity or function of these structures as well as the upper respiratory tract and inner ear.
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