Radiographic findings and clinical factors in dogs with surgically confirmed or presumed colonic torsion

Abstract

Colonic torsion is a life-threatening condition in dogs and radiographic findings for this condition have not been well described. The purpose of this retrospective case series was to describe radiographic findings and clinical signs in a group of dogs with colonic torsion. Inclusion criteria were dogs presenting during the period of 2006 and 2016, and that had abdominal radiography and a surgically confirmed or presumed diagnosis of colonic torsion. For each dog, clinical data were recorded from medical records and imaging findings were recorded from retrieved plain radiographs and positive contrast radiographs in which barium enema was performed. Fourteen dogs met inclusion criteria. Of these, nine dogs had colonic torsion confirmed at surgery, with five dogs having surgical confirmation of colonic congestion or mesenteric torsion. Radiographic findings included segmental distention of the colon (14/14), focal narrowing of the colon (11/14), displacement of cecum (11/14), displacement of descending colon (14/14), and mild to no small intestinal distention (14/14). In cases where barium enema was performed, focal narrowing of the colon and longitudinal striations that course in a helical pattern were identified, termed the "torsion sign." Vomiting was the most common clinical sign observed (12/14), followed by abdominal pain in a small majority of cases (8/14). Severe abdominal pain and hypovolemic shock were uncommon in the patients reported (3/14). Colonic torsion should be considered as a differential diagnosis for dogs with radiographic segmental colonic distention with displacement of the descending colon and cecum. Barium enema is recommended for more definitive diagnosis.

CT findings in five dogs with surgically confirmed colonic torsion

“…Only five dogs satisfied our inclusion criteria, despite the inclusion of eight veterinary hospitals. This supports previous evidence suggesting that colonic torsion is a rare condition in dogs . It is also possible that in many cases of colonic torsion, CT is not required as radiographs can be used to achieve a diagnosis .…”

“…Distension of the colon was defined as a serosa to serosa thickness greater than the total length of L7 . Focal narrowing of the colon was defined as the presence of a sudden reduction in diameter of the colon . Displacement of the cecum and ascending colon, the transverse colon and the descending colon, was defined as the presence of these structures in an abnormal location .…”

“…The radiographic signs of colonic torsion in dogs have recently been described . The most common radiographic signs include segmental distension and focal narrowing of the colon and displacement of the descending colon and cecum.…”

“…The most common radiographic signs include segmental distension and focal narrowing of the colon and displacement of the descending colon and cecum. A “torsion sign,” described as helical striations within the colonic wall, may also be present following the administration of a barium enema . A CT “whirl sign” has been considered a specific feature of organ torsion or volvulus as it reflects the spiral path of the twisted tissue and associated blood vessels .…”

“…1 Both conditions can occur simultaneously and these terms have been used interchangeably in the veterinary literature. 2,3 Clinical signs are nonspecific and include acute or per-acute onset of vomiting, lethargy, abdominal discomfort, and hypovolemic shock. 5 Other clinical signs such as diarrhea, tenesmus, and anorexia have also been reported.…”