Temporohyoid Osteoarthropathy / pharyngeal collapse - update
Temporohyoid Osteoarthropathy (say this three times fast)
Besides being a mouthful, it is a likely diagnosis for my mare, and I'm wondering if anyone has experience with this disorder. Here are a couple of links to articles for anyone who is curious about this.
Background: Horse has a history of refusal to take the bit and resisting any sort of poll flexion. Desperate training measures led to the discovery of a breathing abnormality (restricted airway) and exercise intolerance when ridden with poll flexion. This has grown worse over the past several months.
She shows no neurological symptoms, except for very occasionally aspirating her food (but she is a little piggy, so that my explain that). Various veterinary exams led to a remote dynamic endoscopy last week, followed by endoscopy of the guttural pouches.
The airway obstruction was found to be the result of pharyngeal collapse, for which there is no treatment. No big deal, because I can still ride her on a loose rein.
The guttural pouch endoscopy revealed abnormalities on the right side, with the stylohyoid bone enlarged and covered with emphysema (not to be confused with empyema) and masses of emphysema throughout the guttural pouch. Basically these are gas bubbles throughout the tissue that look sort of like bubbly tumors. Speculation is a stylohyoid fracture.
We also found low WBC count but no sign of infection anywhere (she did have a cold or flu back in October). We are treating with NSAIDs and antibiotics. Not sure what the next step is--probably another CBC and a follow-up endoscopy.
If the diagnosis is correct, the recommendation is for a CT scan followed by ceratohyoidectomy. While medicating we are waiting for the full endoscopy report from the CSU vets. They find my mare very "interesting" -- I do not like when vets find things to be interesting...