Diagnosis and Classification

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1 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at ABDOMINAL EMERGENCIES Diagnosis and Classification of Pancreatic and Duodenal Injuries in Emergency Radiology TEACHING POINTS See last page Ulrich Linsenmaier, MD, PhD Stefan Wirth, MD Maximilian Reiser, MD, PhD Markus Körner, MD Pancreatic and duodenal injuries after blunt abdominal trauma are rare; however, delays in diagnosis and treatment can significantly increase morbidity and mortality. Multidetector computed tomography (CT) has a major role in early diagnosis of pancreatic and duodenal injuries. Detecting the often subtle signs of injury with whole-body CT can be difficult because this technique usually does not include a dedicated protocol for scanning the pancreas. Specific injury patterns in the pancreas and duodenum often have variable expression at early posttraumatic multidetector CT: They may be hardly visible, or there may be considerable exudate, hematomas, organ ruptures, or active bleeding. An accurate multidetector CT technique allows optimized detection of subtle abnormalities. In duodenal injuries, differentiation between a contusion of the duodenal wall or mural hematoma and a duodenal perforation is vital. In pancreatic injuries, determination of involvement of the pancreatic duct is essential. The latter conditions require immediate surgical intervention. Use of organ injury scales and a surgical classification adapted for multidetector CT enables classification of organ injuries for trauma scoring, treatment planning, and outcome control. In addition, multidetector CT reliably demonstrates potential complications of duodenal and pancreatic injuries, such as posttraumatic pancreatitis, pseudocysts, fistulas, exudates, and abscesses. RSNA, 2008 radiographics.rsnajnls.org Abbreviations: AAST = American Association for the Surgery of Trauma, ERCP = endoscopic retrograde cholangiopancreatography, MRCP = MR cholangiopancreatography RadioGraphics 2008; 28: Published online /rg Content Codes: 1 From the Department of Clinical Radiology, Ludwig-Maximilians-University Munich, Nussbaumstrasse 20, D Munich, Germany. Presented as an education exhibit at the 2007 RSNA Annual Meeting. Received April 3, 2008; revision requested June 17 and received July 1; accepted July 9. All authors have no financial relationships to disclose. Address correspondence to U.L. ( ulrich.linsenmaier@med.uni-muenchen.de). RSNA, 2008

2 1592 October Special Issue 2008 RG Volume 28 Number 6 Teaching Point Teaching Point Introduction Blunt pancreatic and duodenal trauma is uncommon, amounting to less than 2% of all abdominal injuries. These injuries often occur during traffic accidents as a result of the direct impact on the upper abdomen of the steering wheel or the handlebars. The duodenum and pancreas can be injured simultaneously; isolated injuries are rare (<30%). Coexisting injuries are common (50% 98%), with an average of three to four for each patient. Identification of a blunt injury of the duodenum and pancreas may be difficult because imaging findings are often subtle. Delays in diagnosis, incorrect classification of the injury, or delays in treatment can increase the morbidity and mortality considerably (1 4). The morbidity and mortality associated with a trauma to the duodenum and pancreas are remarkably high. Mortality for pancreatic injuries ranges from 9% to 34%; for duodenal injuries it ranges from 6% to 29%. However, only 5% of the pancreatic injuries and 30% of the duodenal injuries are directly related to the fatal outcome. The variability in morbidity and mortality is caused by several factors: the presence of coexisting injuries, the mechanism of injury, the time to diagnosis, the presence or absence of major ductal injury, and duodenal perforation, which are considered to be predictors of outcome (5). The probability of complications after duodenal or pancreatic trauma ranges between 30% and 60% and in many cases is the result of missed findings or diagnostic delays or both. Delayed diagnoses and therapeutic interventions often result in a difficult clinical course with a dubious outcome. However, within the first 48 hours after pancreatic injury, most patients succumb to hemorrhage from splenic, hepatic, or vascular injuries (3,5,6). Organ injuries most commonly associated with pancreatic trauma are hepatic (46.8% of cases), gastric (42.3%), major vascular (41.3%), splenic (28.0%), renal (23.4%), and duodenal (19.3%). The high energy transfer and the proximity of the duodenum and pancreas to other vital structures result in few isolated injuries (3,5,6). Coexisting injuries and fatal hemorrhage are responsible for early deaths, while infections and multiorgan failure cause most late ones. Approximately one-third of the patients who survive the first 48 hours develop complications related to their pancreatic or duodenal injury. Common complications of duodenal and pancreatic injuries include pancreatitis, pseudocysts, fistulas, intraabdominal abscesses, pneumonia, and anastomotic breakdown, and these are related to the development of multiorgan failure and septicemia (7 9). About 37% of late deaths are primarily attributable to the injury itself and usually occur within 1 3 weeks of the injury or later (7 9). The time between the injury and the diagnosis and definitive treatment is an important factor in the development of complications and their resulting mortality. When a definitive diagnosis is delayed for more than 24 hours, up to 40% of patients are at risk of death, as opposed to 11% of those patients operated on within 24 hours. Another study has confirmed these observations and notes that all of the deaths directly related to duodenal or pancreatic injuries occurred in cases in which diagnosis was delayed (10 12). Today, computed tomography (CT) provides the safest and most comprehensive means of diagnosis of duodenal and pancreatic injury in hemodynamically stable patients (13 18). In this article, we review anatomic considerations, mechanisms of injury, clinical features, and laboratory findings. We also describe scanning protocols and the current role of multidetector CT, present a grading system for injuries and complications, and discuss the roles of endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance (MR) cholangiopancreatography (MRCP) after trauma. Anatomic Considerations Duodenum The duodenum, the first part of the small intestine, extends from the pylorus to the duodenojejunal flexure, known as the ligament of Treitz. It is divided into four sections: the duodenal bulb, descending part, transverse part, and ascending part. The first part of the duodenum passes backward and upward toward the neck of the gallbladder, and most of it is intraperitoneal. The descending part forms an acute angle, descends 7 8 cm, and is located entirely retroperitoneally. The transverse third part of the duodenum runs cm to the left horizontally and is retroperitoneally located in front of the inferior vena cava, lumbar spine, and aorta. The ascending fourth part of the duodenum runs 2 3 cm retroperitoneally and upward to the left. The superior mesenteric vessels run downward over the anterior surface of the third portion of the duodenum (15,19). Pancreas The pancreas is situated in an upper dorsal retroperitoneal position in a relatively protected zone of the abdominal cavity. The pancreas is about cm long and cm thick; it weighs roughly g.

3 RG Volume 28 Number 6 Linsenmaier et al 1593 Teaching Point Posterior to the pancreas are the aorta, inferior vena cava, left kidney, renal veins, and right renal artery. The pancreatic head lies adjacent to the concave contour of the duodenum. The splenic vein and splenic artery run superior and posterior to the body and tail of the pancreas and can be exposed surgically relatively easily. The proximity of many vascular structures and the far dorsal location of the inferior vena cava and portal vein make injuries to the pancreatic head far more difficult to handle and can affect the morbidity and mortality. The superior mesenteric vein and artery lie just behind the neck of the pancreas and are enclosed posteriorly by the uncinate process. The main pancreatic duct of Wirsung usually traverses the entire length of the gland (15,19). Mechanisms of Injury In general, their retroperitoneal location usually protects the pancreas and duodenum from many instances of minor abdominal trauma. Pancreatic and duodenal injuries usually result only from severe anteroposterior compression trauma against the spinal column, mostly in connection with seat belt injuries, deceleration trauma, and handlebar compression trauma. Less common mechanisms of injury are sports injuries, falls, and blows to the upper abdomen. Most blunt pancreatic injuries (>65%) occur in the pancreatic body. Those to the pancreatic tail and head are less common. Blunt pancreatic trauma is more common among children because of more intense transmission of energy and less protection by a usually thinner layer of peripancreatic fat. Force exerted on the right upper quadrant can affect the pancreatic head or uncinate process and cause injuries in the descending and transverse portions of the duodenum. Coexisting injuries can affect the liver, bile duct, gallbladder, right kidney, and ascending colon. Force exerted on the left upper quadrant results mainly in injuries left of the superior mesenteric artery, to the pancreatic body or tail as well as to the transverse and ascending portions of the duodenum. Coexisting injuries can affect the spleen, stomach, and left kidney (1,3,20,21). Clinical Features Clinical symptoms comprise a triad of leukocytosis, raised serum amylase activity, which can be absent in the first few days, and upper abdominal pain. However, clinical signs are often vague and nonspecific, sometimes even nonexistent. Therefore, major pancreatic injuries can occur with initially minimal epigastric symptoms. Blunt pancreatic and duodenal trauma can occur in patients with multiple trauma, and many will have undergone intubation or received sedatives and therefore cannot provide reliable data for evaluation. To obtain a reliable history in an emergency situation is difficult and in many cases barely feasible. Injuries to the pancreas and duodenum are also likely to be masked by most typical coexisting injuries (1,3,15,22). Laboratory Findings The most common test is the analysis of serum amylase activity. This can be raised, although in up to 40% of cases it remains normal for 2 48 hours after an injury. Repeated testing is recommended, but results do not indicate the severity of the injury. Instead, continuously increased activity or increasing activity are more reliable and have been used for follow-up studies and to monitor the extent of an established pancreatic injury. In addition, the latter features can indicate the need for intervention or operation. Increased activity in general is not specific, as it may occur with salivary gland, facial, small bowel, or hepatic trauma or if the patient is intoxicated. Serum lipase activity is also not specific for pancreatic injury. It has been used in children with pancreatic trauma but is not considered cost-effective. Trypsinogen-activating peptide has not been fully evaluated so far, and no reliable data are available (15,23 25). Multidetector CT Protocols The use of multidetector CT reduces motion artifacts and enables high-resolution scans, in particular high-quality multiplanar reformatted images. The detector collimation of primary axial images is mm and the pitch is , depending on the available scanner technology. In standard CT studies, the axial images are reconstructed with a thickness of mm, but axial images are best reconstructed at mm, with a 10% 20% overlap. The thinnest possible slice thickness should be used for creation of multiplanar reformatted and maximum intensity projection images. Coronal and sagittal reformatted images are used routinely at mm thickness. Curved planes along the duodenal or pancreatic axes are optional to clarify findings. The absence of a pancreatic parenchymal phase (35 40-second delay) in whole-body CT is an obvious limitation of standard portal venous emergency abdominal CT. Combined scans with a whole-body protocol and CT angiography technique are used in most patients with multiple trauma. Although there are no reliable data so far, including the pancreatic parenchymal phase

4 1594 October Special Issue 2008 RG Volume 28 Number 6 Figure 1. Grade I duodenal injury. Axial CT image shows thickening of the duodenal wall (arrow) in the descending part without evidence of free air. There is stranding of the peripancreatic fat. Figure 2. Grade II duodenal injury. (a) Axial CT image shows an enlarged pancreatic head with mild edema (arrow) (grade I lesion). (b) CT image obtained at a lower level shows thickening of the duodenal wall in the descending part (black arrow). Adjacent to the duodenum is a small collection of extraluminal air (white arrow), which indicates a small grade II laceration of the wall. in follow-up CT or in cases of unclear CT findings can be beneficial. Because this scanning phase allows the highest contrast of the pancreatic parenchyma, and optimum enhancement is important in the detection of subtle injuries, it might increase the sensitivity of CT in detection of parenchymal injuries (17,26 29). A volume of ml (2 ml/kg of body weight) of contrast medium (iodine, mg/ml) is injected at 3 6 ml/sec with a delay of seconds in the portal venous (60 70-second) phase. Arterial scans (25 30-second delay) in a whole-body CT protocol or a dedicated pancreatic CT protocol (35 40-second delay) provide images during the pancreatic parenchymal phase. Delayed scanning (at 2 3 minutes) is peformed optionally and is helpful in cases of suspected active abdominal (including pancreatic) hemorrhage. The use of oral contrast media remains controversial, optionally given in one or two doses of ml (17,27 29). The standard CT technique includes the use of positive oral contrast media, if possible. If isolated injury of the duodenum is suspected, dedicated techniques can be applied, such as use of large quantities of negative oral contrast media or sodium bicarbonate or butylscopolamine given orally to distend the duodenal wall (30). These techniques improve the diagnostic quality but are generally not likely to be used for emergency diagnoses. CT Findings in Duodenal Injury CT is an essential means of diagnosing traumatic lesions of the duodenum. Experience has shown

5 RG Volume 28 Number 6 Linsenmaier et al 1595 Figure 3. Grade II duodenal injury. Axial CT image shows a grade II injury of the horizontal part of the duodenum with small collections of extraluminal air (arrows). A subcapsular hematoma is present at the lower pole of the right liver lobe (arrowhead). Figure 4. Grade III duodenal injury. (a) Axial CT image shows thickening of the duodenal wall in the descending part (black arrow). At the transition zone to the horizontal part, there is disruption of the wall (white arrow). Additional findings include a retroperitoneal hematoma and hypoperfusion of the right kidney due to right renal artery occlusion. (b) CT image obtained at a lower level shows the disruption (black arrow) with a large surrounding extraluminal hematoma (white arrow). that nonperforating duodenal conditions can be missed, as only free air or oral contrast medium extravasation are specific signs of duodenal perforation (31,32). Duodenal injuries are the result of penetrating or blunt trauma. It is essential to distinguish between duodenal contusion, hematoma of the duodenal wall, and perforation and disruption; the latter are indications for surgical treatment. If the duodenal injury is associated with a pancreatic injury, distinguishing individual findings at imaging can be particularly difficult. Perforation is most likely to be detected in the descending and horizontal segments. The differentiation of contusion and bowel wall hematomas from perforation is vital. Duodenal perforation is suspected if there is a retroperitoneal collection of contrast medium, extraluminal gas, or a lack of continuity of the duodenal wall. Duodenal contusion is suspected with edema or hematoma of the duodenal wall, intramural gas accumulations, and focal duodenal wall thickening (>4 mm) as findings of small bowel injury. Fluid or a hematoma in the retroperitoneum, stranding of retroperitoneal fatty tissue, or pancreatic transection can be present in both conditions (Figs 1 4) (15,17,18,27,28,30,33 35). A study of 27 children showed that retroperitoneal extraluminal free air or oral contrast material on CT images provided a reliable way to differentiate duodenal perforation from contusions of the duodenal wall (36). In another study, CT Teaching Point

6 1596 October Special Issue 2008 RG Volume 28 Number 6 Figure 5. Grade I pancreatic injury in a patient who experienced blunt abdominal trauma. Axial CT image shows a minor contusion of the pancreatic body (black arrow). There is no pancreatic duct injury and no active bleeding. Note the hematoma of the anterior abdominal wall at the site of the injury (white arrow). In 20% 40% of the cases studied, initial CT findings of patients with pancreatic injuries may be within normal limits in the first 12 hours after the injury; however, much of the published data is still based on the single-detector CT technique. CT diagnosis of pancreatic injuries shows variable sensitivity and specificity because many findings are subtle, absent, or at times slow to develop. The sensitivity and specificshowed that extraluminal contrast medium was not as beneficial as the presence of free air in detecting duodenal perforation; extraluminal air on CT images was present in three of five children with perforation, but none had extravasation of contrast material (31). Most of the contusions of the duodenal wall and hematomas can be treated conservatively, so treatment can vary, depending on whether it is a contusion or a perforation (Figs 1, 3, 4). Mixed attenuation is a sign of duodenal wall hematoma. However, fluid collections in the anterior pararenal space only and thickening of the duodenal wall have been seen in both perforations and duodenal wall contusions (32) (Figs 3, 4). At present, no specific data are available about the sensitivity and specificity of multidetector CT in the diagnosis of duodenal injuries. In a recent study, conventional duodenography showed a 54% sensitivity in the diagnosis of perforation after duodenal trauma if CT findings were not clear; therefore, it cannot be recommended as an adjunct to emergency abdominal CT (37). CT Findings in Pancreatic Injury Correct, early diagnosis of pancreatic injuries is essential for injured patients. Detection of the injury patterns by using CT depends on a reliable and robust technique, particularly timing of an emergency CT study after injury and correct timing of the contrast material bolus, as well as the experience of the radiologist involved (15). Figure 6. Grade II pancreatic injury in a patient who sustained blunt abdominal trauma. (a) Axial CT image shows a major contusion of the pancreatic tail (white arrow). The pancreatic tail is slightly displaced anteriorly because of a peripancreatic hematoma. Both adrenal glands are thickened (black arrows), a finding suggestive of contusions. (b) On an axial CT image, the peripancreatic fat tissue inferior to the pancreatic tail has higher attenuation than the mesenteric fat owing to a hematoma and stranding (white arrow). The left kidney contains a small subcapsular hematoma (grade I) (black arrow).

7 RG Volume 28 Number 6 Linsenmaier et al 1597 Figure 8. Grade III pancreatic injury in a patient who experienced blunt abdominal trauma. (a) Axial CT image shows a complete transection of the distal part of the pancreas (white arrow). Active bleeding is also present (black arrow). An injury to the pancreatic duct was associated with this lesion. The liver and spleen were also injured, resulting in massive intraperitoneal hemorrhage (white arrowheads). Contrast material extravasation as a sign of active bleeding of the spleen is also evident (black arrowhead). (b) Coronal image shows the pancreatic transection (arrows). Figure 7. Grade III pancreatic injury. (a) Axial CT image shows diffuse edema of the pancreatic parenchyma with some defined areas of contusion (black arrow). There is a transection across the pancreatic body (white arrow). A grade II splenic laceration is also present (arrowhead). (b) Axial T2-weighted MR image shows the contusions to the pancreatic body (arrow) and the distal transection (arrowhead). (c) Coronal T2-weighted MR image shows an injury to the pancreatic duct (arrow). ity of CT in detecting pancreatic trauma of all grades are reported to be around 80%, and grades of injury tend to be underestimated with CT (4,20,23,38 41). With the introduction of multidetector CT and the implementation of an adequate technique, higher values should be achievable. The sensitivity of detecting ductal in- jury with multidetector CT has been measured in a single study at 91% (17,28,40). CT findings may be subtle, and sometimes the pancreas may appear normal. The integrity of the pancreatic duct is the most important factor in the decision whether or not to operate. CT is limited in detection of pancreatic injuries when only little peripancreatic fat tissue is present and in detection of subtle pancreatic duct injuries (4,20,38,39,41,42). Specific signs of pancreatic injuries on CT scans are fractures or lacerations of the pancreas, edema or hematoma of the pancreatic parenchyma, active hemorrhage from the pancreas, and blood collections between the parenchyma and the splenic vein (43,44) (Figs 5 10). Teaching Point

8 1598 October Special Issue 2008 RG Volume 28 Number 6 Figure 9. Grade IV pancreatic injury. Axial CT image shows a proximal pancreatic transection (black arrow) with a large peripancreatic hematoma. There is also active bleeding (white arrow). The left kidney demonstrates no enhancement because of an occlusion of the renal artery (grade IV). Pancreatic fractures or lacerations appear as hypoattenuating linear findings, ideally with separated structures, which can be missed on the initial CT images. Multiplanar reformation, thinslice axial image reconstruction, or pancreatic parenchymal phase CT can be beneficial to the quality of diagnosis (Figs 7 10). Pancreatic contusions appear as a diffuse or localized hypoattenuating area within the normally enhancing parenchyma. Complete disruption of the pancreas can result in extended hypoperfusion of the organ (Figs 5, 6). Pancreatic hematomas are mixed attenuation or slightly hyperattenuating lesions within the margins or in contact with the parenchymal structures. A recent study reported that localized blood collections can be found between the parenchyma and the splenic vein in up to 90% of cases of pancreatic injuries (4,20,38,39,41,42) (Figs 5 7). A pancreatic laceration of more than onehalf the diameter suggests ductal injury. Curved plane reformation along the pancreatic duct and nonenhanced CT after ERCP can demonstrate extravasation of contrast medium from the pancreatic duct. If the injury of the pancreatic duct is not clear, MR imaging is used in combination with MRCP and ERCP (Fig 7) (8,15,45). Grading of Pancreatic and Duodenal Injuries The grading of pancreatic and duodenal injuries is recommended to standardize CT diagnoses and to allow objective management, as this is also common practice for other abdominal organ Figure 10. Grade IV pancreatic injury. Axial CT images (a obtained at a higher level than b) show a laceration of the pancreatic neck (arrow) with a pancreatic duct injury. Later in the course, a pancreatic fistula developed (not shown) and was surgically confirmed. injuries such as liver or splenic injuries (46,47). Grading pancreatic and duodenal injuries enables an exact description of injuries, can influence management, and allows a comparison of outcomes and effective quality control of treatment. Major variables for pancreatic injury are anatomic site (proximal compared with distal); the type of injury, such as hematoma, laceration, or transection; and the state of the main pancreatic duct. The most accepted system today was published by the American Association for the Surgery of Trauma (AAST) and differentiates between grade I to V hematomas, contusions, lacerations with and without ductal involvement, and complete disruption of the organ as well as the site of the injuries (Table 1) (48). Major variables for duodenal injury are involvement of one or more portions of the organ, the type of injury (such as hematoma, laceration, or partial or complete disruption), and

9 RG Volume 28 Number 6 Linsenmaier et al 1599 Table 1 Scoring Pancreatic Injury Grade Injury Description I Hematoma Minor contusion without duct injury Laceration Superficial laceration without duct injury II Hematoma Major contusion without duct injury Laceration Major laceration without duct injury or tissue loss III Laceration Distal transection or parenchymal injury with duct injury IV Laceration Proximal transection or parenchymal injury involving the ampulla or bile duct V Disruption Massive disruption of the pancreatic head Source. References 3 and 48. Note. Major variables are site (proximal vs distal), type of injury (hematoma, laceration, or transection), and state of the main pancreatic duct. The AAST system differentiates between hematomas, contusions, lacerations with and without ductal involvement, and complete organ disruption and considers the site of the injuries. Table 2 Scoring Duodenal Injury Grade Injury Description I Hematoma, laceration Involvement of a single portion of the duodenum II Hematoma, laceration Involvement of more than one portion, disruption of <50% of the circumference III Laceration Disruption of 50% 75% of the circumference of D2; disruption of 50% 100% of the circumference of D1, D3, and D4 IV Laceration Disruption of >75% of the circumference of D2 or involvement of the ampulla or distal common bile duct V Laceration, vascular injury Massive disruption of the duodenopancreatic complex or devascularization of the duodenum Source. References 3 and 48. Note. Major variables are involvement of one or more parts of the organ, type of injury (hematoma, laceration, or disruption), and involvement of the ampulla and bile duct. The duodenum is divided into the duodenal bulb (D1), descending part (D2), transverse part (D3), and ascending part (D4). involvement of the ampulla and bile duct. No recent data on CT-based grading are available as yet. However, according to the surgery literature, the AAST grading system (grades I V) is in use. Even if this system is not fully adapted to be used as a CT grading scale the extent of transections, in particular, probably cannot be reliably evaluated with CT it allows the grading of duodenal CT findings (Table 2) (15,49). Complications of Pancreatic Trauma The morbidity ranges between 11% and 62%, covering all types of complications. Most common are pancreatic fistulas (23%), posttraumatic pancreatitis (10%), and the formation of pseudocysts (5%). Posttraumatic internal pancreatic fistulas form an abnormal connection between the pancreas and adjacent organs or spaces and structures owing to continuing leakage of pancreatic secretions from disrupted pancreatic ducts. The mean morbidity rate in patients with pancreatic trauma is 36%, and the mortality for injuries graded I and II is stipulated at around 7%. However, it increases dramatically with grade III and IV injuries to about 29% (15,38,50). Roles of ERCP and MRCP Arguments in favor of using ERCP and MRCP to detect duodenal or pancreatic trauma are not clear, even if they are performed after repeated CT and the ongoing suspicion of pancreatic or biliary duct injury (51 53). ERCP has also been used as a minimally invasive procedure for placement of pancreatic duct stents. It has also been used postoperatively after laparotomy with persistent leakage of pancreatic fluid and with posttraumatic strictures of the pancreatic duct (40,54).

10 1600 October Special Issue 2008 RG Volume 28 Number 6 MRCP and ERCP should be considered only for patients in stable condition, but as an option nonenhanced CT can be performed after ERCP (45,55 61). Conclusions CT of pancreatic and duodenal injuries is challenging and requires close attention to the choice of technique and the subtle signs of injury. Repeated CT should be considered for patients in stable condition when there is a strong suspicion of pancreatic injury despite normal findings at admission CT. Acknowledgments: We thank Sven Mutze, MD, Pierre A. Poletti, MD, Michael Rieger, MD, and Clemens Rock, MD, for their contribution to the manuscript. References 1. Akhrass R, Yaffe MB, Brandt CP, Reigle M, Fallon WF Jr, Malangoni MA. Pancreatic trauma: a tenyear multi-institutional experience. Am Surg 1997; 63: Harris JH, Harris WH. The radiology of emergency medicine. 4th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2000; Jurkovich GJ. Duodenum and pancreas. In: Mattox KL, Feliciano DV, Moore EE, eds. Trauma. 4th ed. New York, NY: McGraw-Hill, 2000; Wilson RH, Moorehead RJ. Current management of trauma to the pancreas. Br J Surg 1991;78: Asensio JA, Demetriades D, Hanpeter DE, Gambaro E, Chahwan S. Management of pancreatic injuries. Curr Probl Surg 1999;36: Sorensen VJ, Obeid FN, Horst HM, Bivins BA. Penetrating pancreatic injuries, Am Surg 1986;52: Jones RC. Management of pancreatic trauma. Am J Surg 1985;150: Patton JH Jr, Lyden SP, Croce MA, et al. Pancreatic trauma: a simplified management guideline. J Trauma 1997;43: ; discussion Sims EH, Mandal AK, Schlater T, Fleming AW, Lou MA. Factors affecting outcome in pancreatic trauma. J Trauma 1984;24: Heitsch RC, Knutson CO, Fulton RL, Jones CE. Delineation of critical factors in the treatment of pancreatic trauma. Surgery 1976;80: Lucas CE, Ledgerwood AM. Factors influencing outcome after blunt duodenal injury. J Trauma 1975;15: Smego DR, Richardson JD, Flint LM. Determinants of outcome in pancreatic trauma. J Trauma 1985;25: Vaughn DD, Jabra AA, Fishman EK. Pancreatic disease in children and young adults: evaluation with CT. RadioGraphics 1998;18: Gupta A, Stuhlfaut JW, Fleming KW, Lucey BC, Soto JA. Blunt trauma of the pancreas and biliary tract: a multimodality imaging approach to diagnosis. RadioGraphics 2004;24: Venkatesh SK, Wan JM. CT of blunt pancreatic trauma: a pictorial essay. Eur J Radiol 2007 Aug 18 [Epub ahead of print]. 16. Brestas PS, Karakyklas D, Gardelis J, Tsouroulas M, Drossos C. Sequential CT evaluation of isolated non-penetrating pancreatic trauma. JOP 2006;7: Shanmuganathan K. Multi-detector row CT imaging of blunt abdominal trauma. Semin Ultrasound CT MR 2004;25: Mirvis SE, Shanmuganathan K. Imaging in trauma and critical care. 2nd ed. Philadelphia, Pa: Saunders/Elsevier Science, Quinlan R. Anatomy, embryology, and physiology of the pancreas. In: Shackelford RT, Zuidema GD, eds. Surgery of the alimentary tract. Philadelphia, Pa: Saunders, 1983; Jeffrey RB Jr, Federle MP, Crass RA. Computed tomography of pancreatic trauma. Radiology 1983; 147: Jeffrey RB Jr, Federle MP, Laing FC, Wing VW. Computed tomography of blunt trauma to the gallbladder. J Comput Assist Tomogr 1986;10: Ilahi O, Bochicchio GV, Scalea TM. Efficacy of computed tomography in the diagnosis of pancreatic injury in adult blunt trauma patients: a single-institutional study. Am Surg 2002;68: ; discussion Bradley EL 3rd, Young PR Jr, Chang MC, et al. Diagnosis and initial management of blunt pancreatic trauma: guidelines from a multiinstitutional review. Ann Surg 1998;227: Greenlee T, Murphy K, Ram MD. Amylase isoenzymes in the evaluation of trauma patients. Am Surg 1984;50: White PH, Benfield JR. Amylase in the management of pancreatic trauma. Arch Surg 1972;105: Linsenmaier U, Krotz M, Hauser H, et al. Wholebody computed tomography in polytrauma: techniques and management. Eur Radiol 2002;12: McNulty NJ, Francis IR, Platt JF, Cohan RH, Korobkin M, Gebremariam A. Multi detector row helical CT of the pancreas: effect of contrast-enhanced multiphasic imaging on enhancement of the pancreas, peripancreatic vasculature, and pancreatic adenocarcinoma. Radiology 2001;220: Mullinix AJ, Foley WD. Multidetector computed tomography and blunt thoracoabdominal trauma. J Comput Assist Tomogr 2004;28(suppl 1):S20 S Wyatt SH, Fishman EK. Spiral CT of the pancreas. Semin Ultrasound CT MR 1994;15:

11 RG Volume 28 Number 6 Linsenmaier et al Jayaraman MV, Mayo-Smith WW, Movson JS, Dupuy DE, Wallach MT. CT of the duodenum: an overlooked segment gets its due. RadioGraphics 2001;21(spec issue):s147 S Desai KM, Dorward IG, Minkes RK, Dillon PA. Blunt duodenal injuries in children. J Trauma 2003;54: ; discussion Zissin R, Osadchy A, Gayer G, Shapiro-Feinberg M. Pictorial review: CT of duodenal pathology. Br J Radiol 2002;75: Dowe MF, Shanmuganathan K, Mirvis SE, Steiner RC, Cooper C. CT findings of mesenteric injury after blunt trauma: implications for surgical intervention. AJR Am J Roentgenol 1997;168: Killeen KL, Shanmuganathan K, Poletti PA, Cooper C, Mirvis SE. Helical computed tomography of bowel and mesenteric injuries. J Trauma 2001;51: Maniatis V, Chryssikopoulos H, Roussakis A, et al. Perforation of the alimentary tract: evaluation with computed tomography. Abdom Imaging 2000;25: Shilyansky J, Pearl RH, Kreller M, Sena LM, Babyn PS. Diagnosis and management of duodenal injuries in children. J Pediatr Surg 1997;32: Timaran CH, Daley BJ, Enderson BL. Role of duodenography in the diagnosis of blunt duodenal injuries. J Trauma 2001;51: Cirillo RL Jr, Koniaris LG. Detecting blunt pancreatic injuries. J Gastrointest Surg 2002;6: Leppaniemi A, Haapiainen R, Kiviluoto T, Lempinen M. Pancreatic trauma: acute and late manifestations. Br J Surg 1988;75: Teh SH, Sheppard BC, Mullins RJ, Schreiber MA, Mayberry JC. Diagnosis and management of blunt pancreatic ductal injury in the era of high-resolution computed axial tomography. Am J Surg 2007; 193: ; discussion West OC, Jarolinek AM. Abdomen: traumatic emergencies. In: Harris JH, Harris WH, eds. The radiology of emergency medicine. 4th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2000; Leppaniemi AK, Haapiainen RK. Risk factors of delayed diagnosis of pancreatic trauma. Eur J Surg 1999;165: Sivit CJ, Eichelberger MR. CT diagnosis of pancreatic injury in children: significance of fluid separating the splenic vein and the pancreas. AJR Am J Roentgenol 1995;165: Lane MJ, Mindelzun RE, Sandhu JS, McCormick VD, Jeffrey RB. CT diagnosis of blunt pancreatic trauma: importance of detecting fluid between the pancreas and the splenic vein. AJR Am J Roentgenol 1994;163: Wong YC, Wang LJ, Chen RJ, Chen CJ. Magnetic resonance imaging of extrahepatic bile duct disruption. Eur Radiol 2002;12: Mirvis SE, Whitley NO, Gens DR. Blunt splenic trauma in adults: CT-based classification and correlation with prognosis and treatment. Radiology 1989;171: Mirvis SE, Whitley NO, Vainwright JR, Gens DR. Blunt hepatic trauma in adults: CT-based classification and correlation with prognosis and treatment. Radiology 1989;171: Moore EE, Cogbill TH, Malangoni MA, et al. Organ injury scaling. II. Pancreas, duodenum, small bowel, colon, and rectum. J Trauma 1990;30: Wong YC, Wang LJ, Lin BC, Chen CJ, Lim KE, Chen RJ. CT grading of blunt pancreatic injuries: prediction of ductal disruption and surgical correlation. J Comput Assist Tomogr 1997;21: Bigattini D, Boverie JH, Dondelinger RF. CT of blunt trauma of the pancreas in adults. Eur Radiol 1999;9: Fulcher AS, Turner MA. Magnetic resonance pancreatography (MRP). Crit Rev Diagn Imaging 1999;40: Fulcher AS, Turner MA, Capps GW, Zfass AM, Baker KM. Half-Fourier RARE MR cholangiopancreatography: experience in 300 subjects. Radiology 1998;207: Fulcher AS, Turner MA, Yelon JA, et al. Magnetic resonance cholangiopancreatography (MRCP) in the assessment of pancreatic duct trauma and its sequelae: preliminary findings. J Trauma 2000;48: Pannu HK, Fishman EK. Complications of endoscopic retrograde cholangiopancreatography: spectrum of abnormalities demonstrated with CT. RadioGraphics 2001;21: Bujanda L, Calvo MM, Cabriada JL, Orive V, Capelastegui A. MRCP in the diagnosis of iatrogenic bile duct injury. NMR Biomed 2003;16: Khalid TR, Casillas VJ, Montalvo BM, Centeno R, Levi JU. Using MR cholangiopancreatography to evaluate iatrogenic bile duct injury. AJR Am J Roentgenol 2001;177: Rescorla FJ, Plumley DA, Sherman S, Scherer LR 3rd, West KW, Grosfeld JL. The efficacy of early ERCP in pediatric pancreatic trauma. J Pediatr Surg 1995;30: Soto JA, Alvarez O, Munera F, Yepes NL, Sepulveda ME, Perez JM. Traumatic disruption of the pancreatic duct: diagnosis with MR pancreatography. AJR Am J Roentgenol 2001;176: Vitellas KM, El-Dieb A, Vaswani K, et al. Detection of bile duct leaks using MR cholangiography with mangafodipir trisodium (Teslascan). J Comput Assist Tomogr 2001;25: Wolf A, Bernhardt J, Patrzyk M, Heidecke CD. The value of endoscopic diagnosis and the treatment of pancreas injuries following blunt abdominal trauma. Surg Endosc 2005;19: Wong YC, Wang LJ, Chen CJ. MRI of an isolated traumatic perforation of the gallbladder. J Comput Assist Tomogr 2000;24:

12 RG Volume 28 Volume 6 October 2008 Lisenmaier et al Diagnosis and Classification of Pancreatic and Duodenal Injuries in Emergency Radiology Ulrich Linsenmaier, MD, PhD, et al RadioGraphics 2008; 28: Published online /rg Content Codes: Page 1592 The probability of complications after duodenal or pancreatic trauma ranges between 30% and 60% and in many cases is the result of missed findings or diagnostic delays or both. Delayed diagnoses and therapeutic interventions often result in a difficult clinical course with a dubious outcome. Page 1592 Coexisting injuries and fatal hemorrhage are responsible for early deaths, while infections and multiorgan failure cause most late ones. Approximately one-third of the patients who survive the first 48 hours develop complications related to their pancreatic or duodenal injury. Common complications of duodenal and pancreatic injuries include pancreatitis, pseudocysts, fistulas, intraabdominal abscesses, pneumonia, and anastomotic breakdown, and these are related to the development of multiorgan failure and septicemia (7 9). Page 1593 Clinical symptoms comprise a triad of leukocytosis, raised serum amylase activity, which can be absent in the first few days, and upper abdominal pain. Page 1595 Duodenal perforation is suspected if there is a retroperitoneal collection of contrast medium, extraluminal gas, or a lack of continuity of the duodenal wall. Duodenal contusion is suspected with edema or hematoma of the duodenal wall, intramural gas accumulations, and focal duodenal wall thickening (>4 mm) as findings of small bowel injury. Fluid or a hematoma in the retroperitoneum, stranding of retroperitoneal fatty tissue, or pancreatic transection can be present in both conditions (Figs 1 4) (15,17,18,27,28,30,33 35). Page 1597 CT findings may be subtle, and sometimes the pancreas may appear normal. The integrity of the pancreatic duct is the most important factor in the decision whether or not to operate. CT is limited in detection of pancreatic injuries when only little peripancreatic fat tissue is present and in detection of subtle pancreatic duct injuries (4,20,38,39,41,42). Specific signs of pancreatic injuries on CT scans are fractures or lacerations of the pancreas, edema or hematoma of the pancreatic parenchyma, active hemorrhage from the pancreas, and blood collections between the parenchyma and the splenic vein (43,44) (Figs 5 10).