Abdominal radiography for diagnosis of enterolithiasis in horses: 141 cases (1990-1992)
Yarbrough, T.B.; Langer, D.L.; Snyder, J.R.; Gardner, I.A.; O'Brien, T.R.
Journal of the American Veterinary Medical Association 205(4): 592-595
1994
ISSN/ISBN: 0003-1488 PMID: 7961097 Document Number: 424816
The clinical signs, diagnosis, site and number of enteroliths were obtained from the medical records of the 141 horses. Radiographs were evaluated individually by 3 reviewers for the presence of enteroliths, preferred diagnostic view, evidence of large colon tympany, and film quality. Enterolithiasis was confirmed in 66.7% (94). Enteroliths were identified in the right dorsal colon of 59 horses, in the transverse colon of 28, in the small colon of 24, and in the ventral colon of 1 (enteroliths were detected in multiple sites in 12 horses). For the 3 reviewers, mean sensitivity was 76.9% and specificity was 94.4%. Mean positive-predictive value was 96.4%, and negative-predictive value was 67.5%. Cases involving only large colon enteroliths were correctly diagnosed 83.2% of the time, compared with 41.6% of the time for cases involving small colon enteroliths. Enteroliths were evident in 54.8% of the horses with radiographic signs of large colon distention. 15 horses had enteroliths in the small colon, 4 in the transverse colon, and 4 in the dorsal colon. Radiographic quality was scored as adequate (0), underexposed (-1), overexposed (1), or incomplete. Mean score was -0.5, and there were 21 (14.9%) incomplete studies. For the 75 cases correctly diagnosed via abdominal radiography, there were 14 (18.7%) incomplete studies and a mean score of -0.43. Of the 19 false-negative evaluations, there were 3 (15.8%) incomplete studies and a mean score of -0.69. The most common error leading to the missed diagnoses seemed to be inadequate penetration of the abdomen.