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CLINICAL IMAGING 1992:16:172-174
INFERIOR MESENTERIC ARTERY BRANCH AVULSION FROM BLUNT TRAUMA-CT FINDINGS CASE REPORT MARY OLSON, MD, HAROLD POSNIAK, MD, AND GILBERT0 GOMES, MD
Mesenteric arterial injuries are uncommon following blunt abdominal trauma. We describe the computed tomography (CT) findings of a patient with avulsion of a branch of the inferior mesenteric artery following a low-speed motor vehicle accident. KEY WORDS:
Computed tomography; Blunt abdominal trauma; Inferior mesenteric artery avulsion; Retroperitoneal hematoma
Computed tomography (CT) is a proven technique for evaluation of intraabdominal injuries following blunt trauma. Retroperitoneal hematomas are not uncommon and are usually caused by fractures of the pelvis or lumbar spine. Rarely, a retroperitoneal hematoma will be the result of a major vascular injury. We present a case of avulsion of a branch of the inferior mesenteric artery (IMA) resulting in a large retroperitoneal hematoma. To our knowledge, the CT findings of traumatic IMA injury have not been previously reported.
CASE REPORT A 68-year-old woman presented to the emergency room complaining of chest and abdominal pain following a low-speed motor vehicle accident in which
From the Department of Radiology, Loyola University Medical Center, Maywood, Illinois. Address reprint requests to: Dr. M. Olson, Department of Radiology, Loyola University Medical Center, 2160 S. First Avenue, Maywood, IL 60153. Received June 10, 1991; accepted December 12, 1991. 0 1992 by Elsevier Science Publishing Co., Inc. 655 Avenue of the Americas, New York, NY 10010 0899-70711921$5.00
she was a restrained passenger. She was hemodynamically stable. An abdominal CT scan showed a large retroperitoneal hematoma that extended from the left upper quadrant to the pelvis and was largest at the level of the aortic bifurcation. It was closely related to the posterior aspect of the pancreas and the descending colon, displacing the descending colon anteriorly indicating its retroperitoneal location. It was separated from the left kidney by the perinephric fat and was not related to the aorta. (Figure 1)There were no other injuries or evidence of a hemoperitoneum. The patient underwent exploratory surgery. A nonexpanding retroperitoneal hematoma due to hemorrhage from a branch of the IMA was found. The IMA was ligated and approximately 1500 cc of clot evacuated. No other significant intraabdominal injuries were found. The left colon remained viable during surgery and at a second-look laparotomy 36 hr later.
DISCUSSION Injury to major abdominal vessels is more common with penetrating than blunt trauma. Approximately 10% to 20% of patients undergoing laparotomy for penetrating wounds have an injury to a major vessel (1). In cases in which blunt trauma is the indication for laparotomy, abdominal vascular injuries are found in only 5% to 10% of patients (1). Blunt trauma is a frequent cause of mesenteric tears but seldom causes injury to the major mesenteric arteries (2). When abdominal vascular injury occurs from blunt trauma, one of two mechanisms is generally responsible. These are avulsion of a branch vessel or an intimal tear with secondary thrombosis (3). In several series of patients sustaining major abdominal vascular injury, trauma to the IMA has been
JULY-SEPTEMBER
1992
TRAUMATIC
IMA AVULSION-CT
FINDINGS
173
FIGURE 1. (A) The superior extent of the hematoma (asterisk] is closely related to the posterior aspect of the pancreas (P) and descending colon [arrow). (B) At the level of the lower pole of the left kidney the hematoma (asterisk) is inhomogeneous with an area of high attenuation (arrows) indicating its acute nature. The hematoma is separated from the kidney by the perinephric fat. (C) The hematoma (asterisk) is largest and most inhomogeneous at the level of the aortic bifurcation. The descending colon (arrow) is displaced by the hematoma.
reported less frequently than trauma to the celiac axis or superior mesenteric artery (SMA) (2, 4, 5).In a series of studies of 66 patients by Graham et al., describing traumatic injuries to the visceral arteries, blunt trauma accounted for injury in four patients (2). All of these were to the SMA. Kashuk et al. reported a series of 161 major abdominal vascular injuries in 123 patients (4).Blunt trauma accounted for 12% of the injuries. None of these injuries involved the IMA. In Ekbom’s series of 81 patients, 10% of the injuries were caused by blunt trauma. No IMA injury occurred. As an isolated finding, retroperitoneal hematoma occurs in only 1% to 2% of nonpenetrating abdominal injuries (6). When acute it is easily identified on CT because of its high attenuation relative to adjacent structures. Our patient had a large retroperitoneal
hematoma (Figure 1).Several features suggested vascular injury to be the cause of the hematoma. There were no adjacent fractures and the retroperitoneal organs including the duodenum, pancreas, and left kidney were intact. The descending colon was adjacent to and displaced by the hematoma. Proximity of the descending colon to the hematoma made inferior mesenteric vascular injury most likely. Computed tomography has been a major technological advance in the evaluation of stable patients with blunt trauma. In many trauma centers, it has become the screening procedure of choice because of its accuracy and its ability to evaluate both the retroperitoneal and intraperitoneal structures. Mesenteric arterial injury from blunt trauma is an unusual cause of an isolated retroperitoneal hematoma on CT. Exclusion of fractures and trauma to retroper-
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OLSON ET AL.
CLINICAL IMAGING VOL. 16, NO. 3
itoneal organs should suggest the diagnosis of vascular injury. The location of the hematoma in relationship to the mesenteric vessels and organs they supply may allow a specific diagnosis in some cases.
3. Feliciano DV. Abdominal 1988;68(4):741-755.
vascular injuries. Surg Clin No Am
4. Kashuk JL, Moore EE, Millikan JS, Moore JB. Major abdominal vascular trauma-a unified approach. J Trauma 1982; 22:672-678.
REFERENCES 1. Feliciano
DV. Approach to major abdominal Vast Surg 1988;7(5):730-736.
vascular injury. J
2. Graham JM, Mattox KL, Beall AC, DeBakey ME. Injuries to the visceral arteries. Surgery 1978;84(6):835-839.
5. Ekbom GA, Towne JB, Majewski JT, Woods JH. Intra-abdominal vascular trauma-a need for prompt operation. J Trauma 1981; 21:1040-1044. 6. Orloff MJ, Charters AC. Injuries of the small bowel and mesen-
tery and retroperitoneal 52(3):729-733.
hematoma.
Surg Clin No Am 1972;
CLINICAL IMAGING 1992:16:172-174
INFERIOR MESENTERIC ARTERY BRANCH AVULSION FROM BLUNT TRAUMA-CT FINDINGS CASE REPORT MARY OLSON, MD, HAROLD POSNIAK, MD, AND GILBERT0 GOMES, MD
Mesenteric arterial injuries are uncommon following blunt abdominal trauma. We describe the computed tomography (CT) findings of a patient with avulsion of a branch of the inferior mesenteric artery following a low-speed motor vehicle accident. KEY WORDS:
Computed tomography; Blunt abdominal trauma; Inferior mesenteric artery avulsion; Retroperitoneal hematoma
Computed tomography (CT) is a proven technique for evaluation of intraabdominal injuries following blunt trauma. Retroperitoneal hematomas are not uncommon and are usually caused by fractures of the pelvis or lumbar spine. Rarely, a retroperitoneal hematoma will be the result of a major vascular injury. We present a case of avulsion of a branch of the inferior mesenteric artery (IMA) resulting in a large retroperitoneal hematoma. To our knowledge, the CT findings of traumatic IMA injury have not been previously reported.
CASE REPORT A 68-year-old woman presented to the emergency room complaining of chest and abdominal pain following a low-speed motor vehicle accident in which
From the Department of Radiology, Loyola University Medical Center, Maywood, Illinois. Address reprint requests to: Dr. M. Olson, Department of Radiology, Loyola University Medical Center, 2160 S. First Avenue, Maywood, IL 60153. Received June 10, 1991; accepted December 12, 1991. 0 1992 by Elsevier Science Publishing Co., Inc. 655 Avenue of the Americas, New York, NY 10010 0899-70711921$5.00
she was a restrained passenger. She was hemodynamically stable. An abdominal CT scan showed a large retroperitoneal hematoma that extended from the left upper quadrant to the pelvis and was largest at the level of the aortic bifurcation. It was closely related to the posterior aspect of the pancreas and the descending colon, displacing the descending colon anteriorly indicating its retroperitoneal location. It was separated from the left kidney by the perinephric fat and was not related to the aorta. (Figure 1)There were no other injuries or evidence of a hemoperitoneum. The patient underwent exploratory surgery. A nonexpanding retroperitoneal hematoma due to hemorrhage from a branch of the IMA was found. The IMA was ligated and approximately 1500 cc of clot evacuated. No other significant intraabdominal injuries were found. The left colon remained viable during surgery and at a second-look laparotomy 36 hr later.
DISCUSSION Injury to major abdominal vessels is more common with penetrating than blunt trauma. Approximately 10% to 20% of patients undergoing laparotomy for penetrating wounds have an injury to a major vessel (1). In cases in which blunt trauma is the indication for laparotomy, abdominal vascular injuries are found in only 5% to 10% of patients (1). Blunt trauma is a frequent cause of mesenteric tears but seldom causes injury to the major mesenteric arteries (2). When abdominal vascular injury occurs from blunt trauma, one of two mechanisms is generally responsible. These are avulsion of a branch vessel or an intimal tear with secondary thrombosis (3). In several series of patients sustaining major abdominal vascular injury, trauma to the IMA has been
JULY-SEPTEMBER
1992
TRAUMATIC
IMA AVULSION-CT
FINDINGS
173
FIGURE 1. (A) The superior extent of the hematoma (asterisk] is closely related to the posterior aspect of the pancreas (P) and descending colon [arrow). (B) At the level of the lower pole of the left kidney the hematoma (asterisk) is inhomogeneous with an area of high attenuation (arrows) indicating its acute nature. The hematoma is separated from the kidney by the perinephric fat. (C) The hematoma (asterisk) is largest and most inhomogeneous at the level of the aortic bifurcation. The descending colon (arrow) is displaced by the hematoma.
reported less frequently than trauma to the celiac axis or superior mesenteric artery (SMA) (2, 4, 5).In a series of studies of 66 patients by Graham et al., describing traumatic injuries to the visceral arteries, blunt trauma accounted for injury in four patients (2). All of these were to the SMA. Kashuk et al. reported a series of 161 major abdominal vascular injuries in 123 patients (4).Blunt trauma accounted for 12% of the injuries. None of these injuries involved the IMA. In Ekbom’s series of 81 patients, 10% of the injuries were caused by blunt trauma. No IMA injury occurred. As an isolated finding, retroperitoneal hematoma occurs in only 1% to 2% of nonpenetrating abdominal injuries (6). When acute it is easily identified on CT because of its high attenuation relative to adjacent structures. Our patient had a large retroperitoneal
hematoma (Figure 1).Several features suggested vascular injury to be the cause of the hematoma. There were no adjacent fractures and the retroperitoneal organs including the duodenum, pancreas, and left kidney were intact. The descending colon was adjacent to and displaced by the hematoma. Proximity of the descending colon to the hematoma made inferior mesenteric vascular injury most likely. Computed tomography has been a major technological advance in the evaluation of stable patients with blunt trauma. In many trauma centers, it has become the screening procedure of choice because of its accuracy and its ability to evaluate both the retroperitoneal and intraperitoneal structures. Mesenteric arterial injury from blunt trauma is an unusual cause of an isolated retroperitoneal hematoma on CT. Exclusion of fractures and trauma to retroper-
174
OLSON ET AL.
CLINICAL IMAGING VOL. 16, NO. 3
itoneal organs should suggest the diagnosis of vascular injury. The location of the hematoma in relationship to the mesenteric vessels and organs they supply may allow a specific diagnosis in some cases.
3. Feliciano DV. Abdominal 1988;68(4):741-755.
vascular injuries. Surg Clin No Am
4. Kashuk JL, Moore EE, Millikan JS, Moore JB. Major abdominal vascular trauma-a unified approach. J Trauma 1982; 22:672-678.
REFERENCES 1. Feliciano
DV. Approach to major abdominal Vast Surg 1988;7(5):730-736.
vascular injury. J
2. Graham JM, Mattox KL, Beall AC, DeBakey ME. Injuries to the visceral arteries. Surgery 1978;84(6):835-839.
5. Ekbom GA, Towne JB, Majewski JT, Woods JH. Intra-abdominal vascular trauma-a need for prompt operation. J Trauma 1981; 21:1040-1044. 6. Orloff MJ, Charters AC. Injuries of the small bowel and mesen-
tery and retroperitoneal 52(3):729-733.
hematoma.
Surg Clin No Am 1972;
