Intestinal stenosis from mesenteric injury after blunt abdominal trauma

Eur. Radiol. 9, 1429±1431 (1999) Ó Springer-Verlag 1999

European Radiology

Case report Intestinal stenosis from mesenteric injury after blunt abdominal trauma A. I. De Backer1, A. M. A. De Schepper1, W. Vaneerdeweg2, P. Pelckmans3 1

Department of Radiology, University of Antwerp, Universitair Ziekenhuis Antwerpen, Wilrijkstraat 10, B-2650 Edegem, Belgium Department of Abdominal Surgery, University of Antwerp, Universitair Ziekenhuis Antwerpen, Wilrijkstraat 10, B-2650 Edegem, Belgium 3 Department of Gastroenterology, University of Antwerp, Universitair Ziekenhuis Antwerpen, Wilrijkstraat 10, B-2650 Edegem, Belgium 2

Received: 10 July 1998; Revision received: 14 October 1998; Accepted: 18 November 1998

Abstract. We report a case in which blunt abdominal trauma resulted in injury to the mesentery with subsequent ischemic stricture of the adjacent small bowel. We present CT images at the time of trauma and 5 weeks later when clinical signs of intestinal obstruction occurred. We include images of enteroclysis and angiography of this uncommon sequela of blunt abdominal trauma. At surgery, a stenotic small bowel loop was found adjacent to a healed defect in the mesentery. Histological examination of the resected segment showed mucosal and submucosal ischemia with mucosal ulceration, mural inflammation, and fibrosis. Posttraumatic intestinal stenosis subsequent to a mesenteric tear should be included in the differential diagnosis in a patient with a history of blunt abdominal trauma and signs of intestinal obstruction. Key words: Blunt abdominal trauma ± Mesenteric injury ± Intestinal obstruction

Introduction Intestinal stenosis is an uncommon sequela of blunt abdominal trauma [1, 2]. We present a case of posttraumatic mesenteric injury with subsequent small bowel stenosis imaged on CT scan, enteroclysis, and angiography. Case report A 46-year-old construction worker was admitted after a fall from a height of 6 m. Awake and cooperative, he complained of lower abdominal pain and pain in his right thigh, ankle, and foot. Radiographic examination revealed several pelvic fractures, a fracture in the right femoral diaphysis, and a fracture with dislocation of Correspondence to: A. I. De Backer

the right ankle and foot, which required immediate reduction to improve circulation to the foot. The patient had tender bruising as well as mild rebound tenderness over the right lower abdomen. Bowel sounds were present. He was hemodynamically stable. Ultrasonography showed minimal fluid in the peritoneal cavity consistent with hemoperitoneum. The liver, spleen, and kidneys were normal. A CT scan of the abdomen and pelvis performed subsequently confirmed the ultrasonographic findings and showed an area of mesenteric haziness and hematoma in the right lower quadrant (Fig. 1). There was no pneumoperitoneum, bowel wall hematoma, or extravasation of intravenously administered contrast material. Surgical intervention was planned, but since the patient improved rapidly and demonstrated normal intestinal function, a conservative approach was thought to be appropriate. The patient made a complete recovery. Five weeks later, the patient complained of abdominal pain, distension, and episodes of diarrhea. A plain radiograph of the abdomen showed several dilated small bowel loops. A CT scan of the abdomen confirmed this finding and showed a narrowed ileal loop in the right lower abdomen (Fig. 2). The patient was treated with nasogastric suction, with improvement in his clinical status. Enteroclysis performed 3 days later showed a prestenotic dilatation of several small bowel loops and a narrowed, ulcerated, and rigid ileal loop in the right lower abdomen (Fig. 3). Angiography showed occlusion of several branches of the superior mesenteric artery with collateral circulation and an abnormal blush of the bowel wall (Fig. 4). The patient underwent laparotomy and resection of the stenotic small bowel loop and made an uneventful recovery. Macroscopically, the stenotic small bowel was thickened with brown discoloration of the serosa (Fig. 5). Adjacent, a healing mesenteric tear with a diameter of 6 cm parallel to the stenotic segment was found. Cut section of the bowel showed alteration, ulceration, and brown discoloration of the mucosa and membranes covering its surface (Fig. 6). Histological findings were consistent

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A.I. De Backer et al.: Intestinal stenosis from mesenteric injury

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Fig. 1. Contrast-enhanced CT performed on the day of trauma shows mesenteric hematoma in the right lower quadrant (arrows). Adjacent, hematoma of rectus muscle sheath is visible. There is also subluxation of right sacroiliac joint Fig. 2. A CTscan after peroral and intravenous contrast administration performed 5 weeks later shows partial small bowel obstruction with wall thickening of the stenotic small bowel segment (arrows) Fig. 3. On enteroclysis there is a concentric narrowed small bowel lumen with mucosal thickening and ulceration and proximal distention (arrows)

Fig. 4. Angiography shows hypervascular blush in the stenotic small bowel wall and occlusion of adjacent branches of superior mesenteric artery with collateral circulation (arrow) Fig. 5. Peroperative photograph of small bowel. Healed defect in mesentery with thickened, fibrotic small bowel adjacent to mesenteric scar (arrows) Fig. 6. Macrophotograph of resected small bowel specimen shows signs of inflammation with mucosal ulceration (arrows)

A.I. De Backer et al.: Intestinal stenosis from mesenteric injury

with mucosal and mural ischemia and fibrosis of the submucosa and muscularis. Discussion Small and large bowel mesenteric injuries from blunt abdominal trauma are rare and often difficult to diagnose. Although the exact incidence of these injuries is unknown, relative incidences of 10 and 13.5 % have been reported in patients undergoing laparotomy [3, 4]. Associated intra- and extra-abdominal injuries are common [5]. Mesenteric injury may elicit life-threatening hemorrhage from disruption of mesenteric vessels and fatal peritonitis from bowel perforation. On the other hand, mesenteric injury may not cause clinical manifestations for days or even months [5, 6]. Breen et al. classified mesenteric injuries as ªmajorº and ªminor.º ªMajorº mesenteric injuries are defined as massive mesenteric tears or transsections associated with vascular compromise of adjacent bowel. ªMinorº mesenteric injuries are defined as small hematomas, contusions, or lacerations without compromise of the bowel circulation [7]. Small lacerations not resulting in significant hemorrhage or devitalization of the bowel still present a risk for internal herniation if left unrepaired. Posttraumatic ischemic bowel stenosis may result from even small tears and contusions [2, 5, 8]. These lesions may cause partial thickness ischemia of the bowel wall, with mucosal ulceration and submucosal inflammation and fibrosis, or may cause full-thickness ischemia with fibrosis of all layers [1, 2]. In either case, this scarring leads to stricture formation and obstruction that typically presents approximately 1 month following injury. Posttraumatic ischemic stenosis is exceedingly rare, and although certainly not all minor undiagnosed mesenteric injuries lead to stricture formation, all represent a risk [5]. Using CT major mesenteric injuries can be identified, and associated injuries to bowel and other abdominal viscera can be demonstrated [6]. The CT findings consistent with mesenteric injury include streaky soft tissue infiltration within the mesenteric fat, fluid collections between the mesenteric folds, and focal intramesenteric hematomas [5, 6]. The ªsentinel clotº sign between bowel loops is highly indicative of mesenteric and gastrointestinal injury [9]. The presence of a moderate to large volume of intraperitoneal fluid without visible solid organ injury can be an important sign of mesenteric or bowel injury [5]. Extravasation of contrastenhanced blood within the peritoneal cavity without signs of solid visceral injury is mostly a consequence of mesenteric and vascular injury [10]. The CT findings of associated bowel injury consist of bowel wall thickening ( > 3 mm), bowel wall discontinuity with extraluminal gas within the mesentery or peritoneal space, and extravasation of orally administered contrast material [7]. Posttraumatic intestinal stenosis is characterized by a delayed onset of obstructive symptoms. Radiographic findings consist of concentric narrowed intestinal lumen of variable length associated with mucosal ulceration [5, 11]. The CT diagnosis of small bowel obstruction is

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based on the change in caliber of small bowel loops proximal to the site of obstruction compared with collapse of bowel segments distal to the obstruction. Whereas CT is a reliable method in detecting the level and cause of obstruction, enteroclysis tests the distensibility and fixation of the small bowel and therefore allows evaluation of the severity of partial mechanical small bowel obstruction better than on CT scan [5, 12]; otherwise information is restricted to the mucosal and submucosal part of the bowel wall. A major drawback of enteroclysis is its reliance on barium, and if CT is requested, this cannot be performed for several days; consequently, CTshould be performed first whenever possible. Angiography shows mesenteric vessel occlusion and ischemic bowel wall enhancement, and thus provides additional information concerning mesenteric injury and subsequent ischemic bowel stenosis. Some patients with a history of blunt abdominal trauma are treated conservatively if CT shows mesenteric hematoma without a substantial amount of intraperitoneal fluid and if signs of peritoneal irritation or hypovolemic shock are absent [13]. If these patients develop signs and symptoms of intestinal obstruction several weeks later, posttraumatic intestinal stenosis should be considered. References 1. Bryner UM, Longerbeem JK, Reeves CD (1980) Posttraumatic ischemic stenosis of the small bowel. Arch Surg 115: 1039±1041 2. Marks CG, Nolan DJ, Piris J et al. (1979) Small bowel strictures after blunt abdominal trauma. Br J Surg 66: 663±664 3. McAnena OJ, Moore EE, Marx JA (1990) Initial evaluation of the patient with blunt abdominal trauma. Surg Clin North Am 70: 495±512 4. Cox EF (1984) Blunt abdominal trauma. Ann Surg 199: 467±474 5. Nolan BW, Gabram SG, Schwartz RJ, Jacobs LM (1995) Mesenteric injury from blunt abdominal trauma. Am Surg 61: 501±506 6. Nghiem HV, Jeffrey RB, Mindelzun RE (1993) CT of blunt trauma to the bowel and mesentery. Am J Roentgenol 160: 53±58 7. Breen DJ, Janzen DL, Zwirewich CV, Nagy AG (1997) Blunt bowel and mesenteric injury: diagnostic performance of CT signs. J Comput Assist Tomogr 21: 706±712 8. Isaacs P, Rendall M, Hoskins EOL et al. (1987) Ischemic jejunal stenosis and blind loop syndrome after blunt abdominal trauma. J Clin Gastroenterol 9: 96±98 9. Orwig D, Federle MP (1989) Localized cloted blood as evidence of visceral trauma on CT: the sentinel clot sign. Am J Roentgenol 153: 747±749 10. Sher R, Frydman G, Russel J, O'Donnell (1996) Computed tomography detection of active mesenteric hemorrhage following blunt abdominal trauma. J Trauma Injury Infect Crit Care 40: 469±471 11. Hirota C, Iida M, Aoyagi K, Matsumoto T, Yao T, Fujishima M (1995) Posttraumatic intestinal stenosis: clinical and radiographic features in four patients. Radiology 194: 813±815 12. Maglinte DD, Gage SN, Harmon BH et al. (1993) Obstruction of the small intestine: accuracy and the role of CT in diagnosis. Radiology 188: 61±64 13. Donohue JH, Federle MP, Griffiths BG, Trunkey DD (1987) Computed tomography in the diagnosis of blunt intestinal and mesenteric injuries. J Trauma 27: 11±17