Laryngeal Paralysis
We seem to have had a run on laryngeal disease over the last month so I thought i would post a quick tutorial. Horses can get a variety of Laryngeal diseases, including arytenoid paralysis, ulcers, neoplasia, epiglottic displacement, epiglottic entrapment and sub-epiglottic cysts. Image 1- This is a normal view through a fiber optic endoscope. What you see is epiglottis in the foreground that looks like a pointed tongue. behind this are the arytenoids that work like curtains covering the opening to the trachea. Image 2- In this horse you can see the left arytenoid is hanging down into the airway. This is an example of Laryngeal paralysis. Frequently this is caused by damage to the left recurrent laryngeal nerve. It can also be related to damage to the arytenoid itself such as infection of the cartilage. This is what typically is known as roaring, when the horse makes a respiratory noise (usually on inspiration) while working. Image 3- This is a picture of an arytenoid ulcer. It is act...