History
A 1-year-old Thoroughbred was evaluated for signs of abdominal pain of a few hours' duration. Analgesics and sedatives had been administered by the referring veterinarian, but there was no improvement in the horse's clinical signs. The horse had been kept in a pasture with Bermuda grass hay, and a high-protein (16%) pelleted feed had been added to the diet 7 days prior to evaluation. On physical examination, the horse was alert and responsive; however, severe signs of pain and distress (sweating, kicking, and wanting to lie down) were detected. On physical examination, the horse had moderate tachycardia (56 beats/min; reference range, 28 to 44 beats/min), had congested mucous membranes with a slightly prolonged capillary refill time (2 to 3 seconds; reference range, < 2 seconds), was estimated to be 6% to 7% dehydrated, and had decreased intestinal borborygmus in all 4 abdominal quadrants. No gastric reflux was obtained after nasogastric intubation. Tight intestinal bands were palpated during rectal examination. Ultrasonography of the abdomen was performed (Figure 1).
Determine whether additional imaging studies are required, or make your diagnosis from Figure 1—then turn the page
Transverse ultrasonographic image of the right ventral portion of the abdomen of a 1-year-old horse with signs of acute abdominal pain of a few hours' duration. Lateral is to the right side of the image. The image was obtained with a 3.5-mHz convex array transducer at a displayed depth of 20 cm.
Citation: Journal of the American Veterinary Medical Association 228, 6; 10.2460/javma.228.6.847
Same ultrasonographic image as in Figure 1. Notice multiple concentric circles representing the large colon wall (a), fecal material and fluid within the lumen of the colon (b), and the cecum (c) and cecal bands (arrowheads). The anechoic center of the image corresponds to free abdominal fluid.
Citation: Journal of the American Veterinary Medical Association 228, 6; 10.2460/javma.228.6.847
Diagnostic Imaging Findings and Interpretation
A thick hypoechoic ring (cecal edematous muscular layer) delineated by 2 hyperechoic rings (cecal serosa and mucosa layers) inside a similar structure corresponding to the colonic serosa, edematous (thick hypoechoic) muscularis, and mucosa layers is evident. These ultrasonographic findings are compatible with a cecocolic intussusception (Figure 2). The cecal and colonic walls are separated by liquid fecal material in the right ventral colon. These ultrasonographic findings were visualized in almost the entire ventral portion of the abdomen on the right side from the level of the lumbar vertebrae to the level of the eighth and ninth ribs. The cranial extent of the lesion helped to distinguish a cecocolic from a cecocecal intussusception, where the latter would have a similar ultrasonographic appearance but would have been detected in a smaller area within the abdominal cavity.
Comments
Cecocolic intussusception results from invagination of the cecum (intussusceptum) through the cecocolic orifice into the right ventral colon (intussuscipiens)1 and is characterized by a single episode of acute abdominal pain or a chronic and intermittent colic, which results in wasting disease.2 Cecal intussusceptions (cecocolic or colocolic) develop frequently in horses < 3 years old.3 The preoperative diagnosis of cecocolic intussusception is difficult to determine; it can be suspected on the basis of finding a mass or edematous intestine in the right caudodorsal aspect of the abdomen during rectal palpation.4 Ultrasonographic evaluation of the abdominal cavity in horses with colic can be valuable in the preoperative diagnosis of intussusceptions. This condition can be identified as multiple concentric rings (bull's-eye) separated by fluid corresponding to the transverse view of the different layers of the intussusception.5 In the horse of this report, cecocolic intussusception was preoperatively diagnosed on the basis of the ultrasonographic findings evident in the right caudal portion to the right cranial portion of the abdomen in which the right ventral colon usually exists.
Surgical intervention is required for correction of cecocolic intussusceptions. Different techniques have been described, including manual reduction,6 reduction with partial typhlectomy,7 cecal amputation through a right ventral colotomy in nonreducible cases,1 total typhlectomy,3 or bypass by ileocolostomy.4 In the horse of this report, the intussusception was manually reduced, and a partial typhlectomy of the apex of the cecum was performed because the apex did not appear viable. The horse recovered without complications and remained in the hospital for 7 days. Results of other studies indicate that 7 of 8 horses1 and 14 of 17 horses4 survived long term after undergoing surgical correction of cecocolic intussusceptions through manual reduction alone or reduction through a colotomy, with or without partial typhlectomy or ileocolostomy.1,4
- 1↑
Hubert JD, Hardy J, Holcombe SJ, et al. Cecal amputation within the right ventral colon for surgical treatment of nonreducible cecocolic intussusception in 8 horses. Vet Surg 2000; 29: 317–325.
- 2↑
Allison CJ. Invagination of the caecum into the colon in a Welsh Pony. Equine Vet J 1977; 9: 84–86.
- 3↑
Robertson JT. Cecocolic and colocolic intussusception. In: White NA, Moore JN, eds. Current practice in equine surgery. Philadelphia: JB Lippincott Co, 1990;334–336.
- 4↑
Martin BB, Freeman DE, Ross MW, et al. Cecocolic and cecocecal intussusception in horses: 30 cases (1976–1996). J Am Vet Med Assoc 1999; 214: 80–84.
- 5↑
Bernard WV, Reef VB, Reimer JM, et al. Ultrasonographic diagnosis of small-intestinal intussusception in three foals. J Am Vet Med Assoc 1989; 194: 395–397.
- 6↑
Gaughan EM, Hackett PR. Cecocolic intussusception in horses: 11 cases (1979–1989). J Am Vet Med Assoc 1990; 197: 1373–1375.
- 7↑
Foerner JJ. Diseases of the large intestine: differential diagnosis and surgical management. Vet Clin North Am Large Anim Pract 1982; 4: 129–146.
