Diagnosis is made through endoscopy revealing the prolapse of one or both vocal folds.
Treatment is surgical or laser laryngoplasty, a procedure that is commonly called “tie-back” surgery.
Prognosis is good for horses treated through laryngoplasty.
Epiglottic Entrapment
Epiglottic entrapment occurs when the epiglottis becomes entrapped, or stuck, in the folds of the . This fold or flap of mucous membrane is located between the epiglottis and the arytenoidus cartilage. If the mucous membrane of the upper respiratory tract is inflamed, there are palatine defects, or the epiglottis is congenitally the epiglottis can be forced under the aryepiglottic fold by the forceful ventilation during exercise and become entrapped there. The entrapped epiglottis partially blocks the lumen of the airway causing turbulent airflow. Turbulence causes irritation, inflammation and ulceration of the aryepiglottic fold and the epiglottis. If epiglottic entrapment becomes chronic the tissues become fibrotic and deformed and may form between the epiglottis and the aryepiglottic fold making the entrapment permanent.
Deformity of the epiglottis or soft palate may predispose the horse to epiglottic entrapment.
The clinical presentation of epiglottic entrapment includes exercise intolerance, coughing and respiratory stridor that is more pronounce during exercise. Diagnosis is made through endoscopy revealing the abnormal placement of the epiglottis within the aryepiglottic fold. endoscopy may be required to visualize the epiglottic entrapment as some individuals only exhibit entrapment during exercise.
Treatment includes the surgical resection of the aryepiglottic fold to free the epiglottis.
Prognosis is guarded as fibrosis and adhesions may distort the airway making turbulent airflow permanent.
Dorsal Displacement of the Soft Palate
Dorsal displacement of the soft palate is commonly referred to as “
”
or “choked down”.
Inflammation of the upper respiratory tract or retropharyngeal lymphadenopathy causes pressure on the axon of cranial nerve X, the nerve. Pressure reduces the neuromuscular control of the soft palate allowing the caudal margin of the soft palate to become displaced dorsal
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