In the lead up to this year's Breeders' and Melbourne Cups, PET and CT units have been at the crux of dashed dreams, with several horses scratched from these contests due to unsatisfactory PET and CT scans. But how do veterinarians decide what's satisfactory and what isn't? It's in the last few years these technologies have emerged at the cutting edge of efforts to determine the root cause of subtle lameness in racehorses. This period has proven a fast learning curve for diagnosticians--just ask Ryan Carpenter, a SoCal-based vet who...