bone scan ?'s again

["guest@endurance.net" <guest@endurance.net>]

Tiffany tiffshorse@mindspring.com
>>So Tiffany; Do they scan the whole horse?  We scan the whole person at City of Hope. Then the film looks like tiny little skeletons.  Why do the radiology department people ask about iodine allergies?I don't know why the vet even mentioned the bone scan.   We did Xrays of the fetlock,pastern and hoof almost a month ago.  The horse is not healing, and is getting progressively worse. :.  Anyway we already did X-rays and they are negative.    I probablly won't do the bone scan anyway if it's just diagnostic and doesn't affect the course of therapy , because I suspect I cannot afford it. No money flying around here! <<

I am posting this to the group, as I hope we can get something out of it should anyone else need to get one for their horse. They would not do the whole area, just the affected part. Even in humans, we do affected part only in injury cases. Cancer is always whole body. The rationale for the scan is probably this...A bone scan is MUCH more sensitive than an x-ray. So, in light of the ongoing problems and negative films, the vet may still suspect something going on. Infection vs. fracture. So, the bone scan is going to show any reactive process where either the blood supply is increased or the bone is more active. On a bone scan should the blood flow, the tissue phase and the actual scan be hot, it most likely represents either a fracture or osteomyelitis. If the first two phases are hot and the scan (3rd phase) is normal you are looking at cellulitis. A scan, combined with films will let you know if something like an infection or hairline fracture had occured. Gosh, I hope that was understandable. They can be an invaluable tool, especially in the face of the mystery injury. An xray isn't even going to be in the same ballpark for sensitivity. Good luck! 
Tiffany