In one sense I wish they hadn't done the additional scope and still wonder if the condition of the guttural pouch had something to do with the nasty cold/flu/cough she had in October (lingering inflammation?).
On the other hand, the medicine did make her feel better and within a few days of starting them she perked up and started running around the pasture more.
It is tempting to leave her on the Previcox awhile longer and wait longer to rescope, but when I mentioned waiting a few months the doctor disapproved. My reasoning, perhaps faulty, is that if she is going to get better she will still be better in three months. If she gets worse she probably won't die. And I will have more time to staunch my bleeding wallet. Hmmph!
Since my last post I have had a couple of people ask me about this, so I thought I would post a quick status update.
In May I took Shelby back to CSU for a follow-up exam. They scoped the guttural pouch again and it has not changed -- still has the emphysema, no better and no worse.
The internist was really bothered that the air bubbles were obscuring the temporohyoid bone, so she talked radiology into climbing under her to get a good view of both sides. The temporohyoid joints appeared to be normal and of equal size.
Still no explanation for the bubbles or for the pharyngeal collapse. The only other course would be a CT scan, which is very expensive, requires general anesthesia and does not seem warranted.
A chiropractor went over her and found some stiffness around the poll and TMJ. He was interested to know how her heat cycles were and suggested palpating her ovaries. While she was a raging bitch that day, it was not hormonal. That is just what she does when she goes to the vet hospital with her herd-mate and then gets separated from him. At home she is very steady and I can barely even tell when she's in heat, so I elected to preserve her innocence and not "go there" just yet.
Since my only other rideable horse has been lame, I have made Shelby my new "dressage" horse and started over with her training. She has come a long way since spring and is now able to go round and on the bit in the walk and trot without resistance (canter is a work in progress).
I discovered that if I keep her neck relaxed and stretching then the breathing is easier for her. When she braces or pulls against me, the breathing becomes louder and more labored. She gets very anxious, so keeping her relaxed is not easy, but getting so much better.