Protocol for Pre-Sale Videoendoscopic Examination of the Upper Airway at Public Auction

Equipment must be capable of producing a digital video image of excellent quality.

Horse must be identified appropriately, and that identification must be in digital format with character generation on the screen. Given that microchips are a requirement of registration for foals, it is recommended that the video identification include the scanning of the microchip and subsequent visualization of the chip number, and video of the catalog page or stall card, followed by unbroken video of the face prior to introduction of the scope into the nares (right or left) and up to the larynx. The embedded digital annotations should include the date and time of the examination. This is a single stream video with no editing. Upper airway videos should be stored in a file separate from the radiographs in the repository in case of client request for one or the other.

Standard technique must include maximal abduction of arytenoids induced by swallowing (multiple times) and nasal occlusion. The duration of the video must be sufficient to identify all laryngeal and pharyngeal structures as well as observing their maximal function within the context of a resting exam.

Endoscopic technique

• Either nostril may be used for introduction of the endoscope; however, every attempt should be made to maintain the endoscope centrally in the nasopharynx to minimize parallax error when assessing the laryngeal cartilages. Orientation of the laryngeal image should be vertical at all times.
• The initial footage should permit clear, unobstructed visualization of the entire epiglottis, arytenoid cartilages, and vocal cords/ventricles. The endoscope should be advanced close enough to the larynx to allow thorough assessment of the mucosal surfaces in order to permit detection of ulceration or chondritis. Touching or prodding of the arytenoid cartilages with the endoscope is to be discouraged.
• Laryngeal function grading systems are founded on assessment of arytenoid cartilage movements. Video footage should permit visualization of the larynx not only at maximal abduction but also periods of full relaxation, in order that the full range and synchrony of arytenoid movements can be observed.
• In order to permit detection of both static and dynamic abnormalities, the minimum acceptable time of direct visualization of the larynx (i.e., exclusive of passage of the endoscope through the nasal passages) should be at least 45 seconds and preferably 60 seconds. This time should be used constructively by the acquiring veterinarian to stimulate the larynx when necessary; long videos that do not document the full range of movements should be discouraged. It is stressed that quality of video footage and technique used are of much greater importance than overall length of video.

The interval between the pre-sale videoendoscopic exam and the selling session will not exceed (10) days.

Revised by AAEP board of directors in 2024.