Dynamic Respiratory Endoscopy

Dynamic respiratory endoscopy (DRE) or dynamic overground endoscopy (DOE) is an exciting technology that has made substantial improvements in our ability to accurately diagnose, and subsequently treat, upper respiratory disorders in horses exercising under their normal environmental conditions.


DRE/DOE is indicated in horses with upper airway disorders, abnormal noise production during exercise, exercise intolerance, and poor performance.

Dynamic obstructions of the upper respiratory tract often times only occur during high-speed and intense exercise. As a result, these transient events are likely under diagnosed or misdiagnosed by resting endoscopic examination alone. Until recently, exercising endoscopic examination of the upper respiratory tract in horses was only available via high speed treadmill examination. However, with the advent of DRE/DOE, endoscopic examination of horses in their normal exercising conditions and in their natural environment is now possible.  DRE/DOE thus eliminates the need for treadmill examination, is safer, less expensive, and more convenient for both you and your horse.


How is a DRE/DOE examination performed? Once you call and schedule an appointment for your horse, we will travel with the DRE/DOE equipment to your horse’s normal training facility to conduct the examination. The dynamic endoscope is similar to a normal resting endoscope and is inserted into one of your horse’s nostrils. After ensuring correct positioning of the endoscope in the airway, the endoscope is secured to the horse via a special purpose noseband that fits over the horse’s bridle.

The transmitting-recording devices are mounted within custom designed saddle pads for driving and riding disciplines. The video-endoscopic images are recorded continuously onto an SD card in the recording device while the horse performs its normal exercise routine under the conditions in which the abnormality in performance was noted. Real time visualization of the horse’s upper airway is also possible through a portable, wireless monitor. Once the horse finishes exercising and the examination is complete, the video-endoscopic recording is reviewed with a specialized software program which allows the videos to be played in slow motion and still images obtained. Images from the workout can then be emailed or recorded onto a CD/DVD for all interested parties to view.



Left Laryngeal Hemiplegia

Dorsal Displacement of the Soft Palate

Axial Deviation of the Aryepiglottic Folds