Digital radiography can locate enteroliths in a horse’s gut as well as or better than do conventional x-rays.
Enteroliths are stone-like concretions that form in layers in a horse’s large colon. When they are large or numerous, they can cause colic because they interfere with gut motility or create blockages.
Film-based radiography has been the traditional method of detecting enteroliths in horses, but recently researchers at the University of California–Davis devised a study to determine if digital radiology, which produces images more quickly, can be equally effective.
The researchers reviewed the records of 238 horses diagnosed with enteroliths using digital radiography who then underwent surgery or a postmortem examination that confirmed the presence of the stones. The data revealed that digital radiography had a sensitivity rate of 84 percent to detect a stone in the large colon, meaning that if a stone were present, digital radiography could locate it 84 percent of the time. This is significantly better than the sensitivity rate of film radiography, which previous studies have shown to be 77 percent.
The researchers also found that digital radiography had a specificity rate of 96 percent to detect a stone in the large colon, meaning that 96 percent of the time when a stone isn’t seen on the radiographic image, none is present. They conclude that digital radiography “has the potential to be an important part of the diagnostic workup of horses and ponies with colic and abdominal disease in [enterolith] endemic areas.”
Reference: “Use of digital abdominal radiography for the diagnosis of enterolithiasis in equids: 238 cases (2008-2011),” Journal of the American Veterinary Medical Association, July 2014
This article first appeared in EQUUS issue #446, November 2014.