The thing to remember with CT is that an x-ray is going to capture that specific moment so if the dog is inhaling, exhaling, or somewhere in between that is what is captured. A scope looks inside the trachea and can see the locations and severity of the collapse. The scope can also identify any other potential problems such a bacteria, damage, etc.  Baby Girl's x-ray was the first step to identify the CT, then we had a consultation here in town with UT Veterinarian Dr. Kranwinkel, then we went to UT for our visit  where BG was scoped and received the stent........Jana