Pancreatic Injuries in Blunt Abdominal Trauma

Rob Gordon BUSM 2010Beth Israel Deaconess Medical Center

Dr. Gillian Lieberman

Presentation overviewAn index patient presentationOverview of pancreatic injury in blunt abdominal traumaThe role of multi‐row detector CT imagingCompanion patients with imaging findings suggestive of pancreatic injuryCompanion patients demonstrating imaging pitfallsOutcome for our index patientAcknowledgements and References

Our index patient:A 49 year old male who was an unrestrained driver in a motor vehicle collision He had loss of consciousness, difficulty breathing and diffuse abdominal pain in the fieldCool, pale and diaphoretic on arrival to ER. BP in the field in the 90’s with HR in the 70’sSignificant lab values: Amylase 142, Lipase 62, creatinine 1.2, Hemoglobin 10 and Hematocrit 28.

CT image findings for our patient:

Axial contrast enhanced CT images with free fluid surrounding the liver (blue star) and peripancreatic fluid.

All images courtesy of BMC PACS

Axial contrast enhanced CT images demonstrating hypoattenuating fluid between the splenic vein and posterior border of the pancreas (blue arrow).

A more concerning finding in our index  patient is a possible pancreatic laceration

Axial contrast enhanced CT image that shows an hypoattenuating linear lesion (blue arrow) through the pancreas. This lesion extends through >50% of the parenchyma.

Image courtesy of BMC PACS

Some background on pancreatic  injuries in blunt abdominal trauma:

Pancreatic injuries caused by blunt trauma is exceedingly rare (incidence 0.2‐12%)Clinical and laboratory findings are nonspecificEarly diagnosis is critical in reducing morbidity and mortalityMain pancreatic duct disruption is the greatest predictor for complications.

http://www.nativeremedies.com/images/design/ailmentPhotoPancreas.jpg

Mechanism of Pancreatic Injury 

• Blunt pancreatic injury 

occurs with compression of 

pancreas between the 

vertebral column and 

anterior abdominal wall.• Adults –

motor vehicle 

accidents

• Adolescents – bicycle 

handlebar injuries

• Infants – child abuse

Pancreatic injury is more common in children and young adults because of decreased protective intra‐abdominal fat

http://www.radiologyassistant.nl/images/thmb_43ce5595362a9abdom-trauma-child-abuse.jpg

Companion patient #1: Mortality in pancreatic trauma

Mortality rates in blunt pancreatic injury range from 10% to 30%

Most deaths occur within the first 48 hours due to acute hemorrhage of traumatized vasculature including:

splenic veinportal veininferior vena cava

Axial contrast enhanced CT image demonstrating transection of pancreatic head and body with active extravasation of contrast fluid (arrow heads).

Gupta et al. Radiology 2004)

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Gupta et al. Radiographics 2004.

Left: Companion patient 2: Axial contrast enhanced CT image with a loculated fluid collection (*) representing a pseudocyst.

Right: Companion patient 3: Axial contrast enhanced CT image in a patient 6 days after trauma showing expanding fluid collections within the pancreas. Gupta et al. Radiographics 2004.

Diagnosing Pancreatic injury: The Role of Multi‐detector CT.

• Computed tomography is the imaging modality of choice  in patients with blunt abdominal trauma

• CT provides an excellent initial evaluation for the  detection and characterization of solid visceral organ 

injury• The sensitivity for pancreatic injury is between 67%‐85% 

(mainly based on single detector CT)• Pancreatic injuries tend to be subtle, particularly within 

the first 12 hours after the traumatic event• MDCT provides improved evaluation of pancreatic duct 

integrity, which is of the utmost importance in triaging  patients with pancreatic injury

CT imaging findings suggestive of  pancreatic injury: 

Peripancreatic fluid collectionsHyperattenuation / Active extravasationContusion / Pancreatic enlargementPancreatic hematomaLaceration / Fracture

Companion Patient #4 and #5: Superficial  Lacerations without ductal involvement

Rekhi et al. Emergency Radiology 2009.

Above: Companion patient 4: Axial contrast enhanced image showing a linear hypoattenuating line through <50% of the pancreas. Note depth of laceration <50% corresponds with decreased chance of main pancreatic duct involvement.

Below: Companion patient 5: Axial contrast enhanced CT image with superficial laceration through the tail of the pancreas. Laparotomy confirmed the pancreatic duct remained intact.Gupta et al. Radiographics 2004

3 images from Gupta et al. Radiographics. 2004

Companion patient 6: Axial contrast enhanced CT image showing fracture of the pancreatic tail. Ductal involvement should be confirmed with MRCP or surgery.

Companion patient 7: Axial contrast enhanced CT image demonstrating transection through the pancreatic neck.

Companion patient 8: Axial contrast enhanced CT image with laceration through more than 50% of the parenchyma. Ductal disruption was confirmed at surgery.

Companion patient # 9:  Peripancreatic fluid Collections

Axial contrast‐enhanced CT image with significant peripancreatic and intra‐abdominal fluid collections. Peripancreatic fluid is a very sensitive but non‐specific imaging finding in pancreatic trauma. Fluid is commonly found between the splenic vein and inferior border of the pancrea. 

Image courtesy of BMC PACS

2 Axial contrast‐enhanced CT  images with hematoma 

surrounding the pancreas.  Pancreatic hematoma present 

as areas of heterogenous attenuation within or 

surrounding the parenchyma.  Actively bleeding hematoma 

will not show washout on  delayed phase imaging 

2 images from Rekhi et al. Emergency Radiology 2009.

Rekhi et al. Emergency Radiology 2009.

Image courtesy of BMC PACS

Above: Companion patient 11: Axial portal venous phase image showing multiple areas of active contrast extravasation.

Below: Companion patient 12: Delayed phase image showing sustained hyperattenuation indicative of active hemorrhage.

Companion patient 13: Axial contrast enhanced CT image with focal area of relative hypoattenuation within the neck of the normally enhancing parenchyma indicative of pancreatic contusion.Rekhi et al. Emergency Radiology 2009

Companion patient 14: Axial contrast enhanced CT image with area of hypoattenuation within the body of the pancreas.

Rekhi et al. Emergency Radiology 2009

Companion patient 15: Axial contrast enhanced CT image with area of hypoattenuation within the head of the pancreas. Associated with relative engorgement of the surrounding parenchyma.

Image courtesy of BMC PACS

Inherent characteristics of pancreatic  injuries that can cause defects to be missed:

There are a number of characteristics of pancreatic injuries that lead to both false positive and false negative results on CT imaging.Injuries can often be subtle and require both the keen eye of the radiologist and the clinical suspicion of the surgical team.

Reasons for false negatives:Obscured fracture planesSurrounding hemorrhageClose apposition of pancreatic fragmentsAssociated injuries – satisfaction of search

***many of these changes will present on follow up exams***

Reasons for false positives: Peripancreatic fluid after aggressive fluid resuscitationPeripancreatic fluid from an alternative sourceAtrophic or fatty pancreasPancreatic clefts

Companion Patient #16: Diagnostic  difficulties in Pancreatic trauma:

Given the high impact mechanisms, pancreatic injury rarely occurs in isolation. Pancreatic injuries may be obscured by associated injuries. 

Associated injuries to the liver, spleen, duodenum and kidneys, occur in 90% of events

Serum enzymes are neither sensitive not specific

Initial serum amylase/lipase levels normal in 40%

Axial contrast enhanced CT image with splenic and right adrenal hematoma in a patient with full transection of the tail of the pancreas. Rekhi et al. Emergency Radiology 2009.

Companion patient # 17:  Sources of Fluid in the  Pararenal Space without Pancreatic injury: 

Aggressive fluid resuscitationHypovolemic shock complex Blood dissecting from an intraperitoneal viscus injuryFluid traveling via the splenorenal ligament after injury to the splenic hilumFluid traveling thorough direct extension with injury to the bare area of the liverBlood or bowel contents from duodenal injury and bloodUrine dissecting from a renal injury following disruption of the posterior renal fascia 

Rekhi et al. Emergency Radiology 2009.

Axial contrast enhanced CT image with significant peripancreatic fluid after aggressive fluid resuscitation. The patient was treated conservatively without pancreatic complications.

Companion patient #18: Asymmetric fatty  Atrophy of the Pancreas – Not to be confused 

with pancreatic contusion!Coronal (above) and axial 

(below) contrast enhanced  CT images of a patient 

with areas of  hypoattenuation caused by 

separation of the  parenchyma by intermixed 

fat. This normal variant  seen in obese and elderly 

patients may be  misinterpreted as 

pancreatic contusions or  fractures. 

2 Images courtesy of BMC PACS.

Companion patient #19: Pancreatic Clefts – Not to be confused for pancreatic lacerations!

Coronal (above) and axial (below) 

contrast enhanced CT images of a 

patient with multiple linear 

hypoattenuating lesions with the 

pancreas created by fat that 

surrounds arterial and venous 

vessels that penetrate the pancreas. 

This is a normal variant that may be 

misdiagnosed as fractures

Images courtesy of BMC PACS

Our patient was taken to the OR for emergent laparotomy. Findings included:

• Retroperitoneal hematoma and edema near and around the head of the pancreas. •No evidence of any active bleeding, but there was some clear fluid coming from the area. •Fracture through the tail of the pancreas

•These findings were in agreement with our imaging findings discussed at the beginning of this presentation.

2 images courtesy of BMC PACS

2 axial contrast enhanced images at the level of the pancreas

ReferencesCirillo RL Jr, Leonidas GK (2002) Detecting blunt pancreatic injuries. J Gastrointest Surg 6:587–589. Rekhi, S., Anderson, S., Rhea, J., Soto, J. (2009). Imaging of blunt pancreatic trauma. Emergency Radiology..Gupta A, Stuhlfaut JW, Fleming KW, Lucey BS, Soto JA (2004) Blunt trauma of the pancreas and biliary tract: a multimodality imaging approach to diagnosis. Radiographics24:1381–1395. Jurkovich GJ (2000) The duodenum and pancreas. In: Mattox KL, Feliciano DV, Moore EE (eds) Trauma, 4th edn. McGraw‐Hill, New York, NY, pp 735–762Wong 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; 21:246‐250. Fischer JH, Carpenter KD, O’Keefe GE. CT diagnosis of an isolated blunt pancreatic injury. AJR Am J Roentgenol 1996; 167:1152. Ilahi O, Bochicchio GV, Scalea TM (2002) Efficacy of computed tomography in the diagnosis of pancreatic injuries in adult blunt trauma patients: a single‐institutional study. Am Surg 68:704–708 Akhrass R, Yaffe MB, Brandt CP et al (1997) Pancreatic trauma: a ten‐year multi‐institutional experience. Am Surg 63:598–604 Madida TE, Mokoena TR (1995) Favorable prognosis after surgical drainage of gunshot, stab or blunt trauma of the pancreas. Br J Surg 82:1236–1239.Lin BC, Chen RJ, Fang JF et al (2004) Management of blunt major pancreatic injury. J Trauma 56:774–778Wolf A, Bernhardt J, Patrzyk M et al (2005) The value of endoscopic diagnosis and the treatment of pancreas injuries following blunt abdominal trauma. Surg Endosc 19:665–669 Tyburski JG, Dente CJ, Wilson RF et al (2001) Infectious complications following duodenal and/or pancreatic trauma. Am Surg 67:227–231 Bradley EL 3rd, Young PR Jr, Chang MC, et al. Diagnosis and initial management of blunt pancreatic trauma: guidelines from a multi‐institutional review. Ann Surg 1998; 227:861– 869. Dawson AR, Webster CH, Howe HC, Theron EJ, Meiring L. Rupture of the head of the pancreas by blunt trauma: a case report. S Afr Med J 1985; 67:560‐562. Jones RC. Management of pancreatic trauma. Am J Surg 1985;150:698–704. Davis JJ, Cohn I, Nance FC. Diagnosis and treatment of blunt abdominal trauma. Ann Surg 1976; 183:672–678. Lucas CE. Diagnosis and treatment of pancreatic and duodenal injury. Surg Clin North Am 1977; 57:49–65. Cogbill TH, Moore EE, Kashuk JL. Changing trends in the management of pancreatic trauma. Arch Surg 1982; 117: 722–728. Smego DR, Richardson JD, Flint LM. Determinants of outcome in pancreatic trauma. J Trauma 1985; 25:771–776. Wisner DH, Wold RL, Frey CF. Diagnosis and treatment of pancreatic injuries. Arch Surg 1990; 125:1109–1113. Wilson RH, Moorehead RJ. Current management of trauma to the pancreas. Br J Surg 1991; 78: 1196 –1202. 

ReferencesJurkovich GJ, Carrico CJ. Pancreatic trauma. Surg Clin North Am 1990; 70:575–593. Northrup WF III, Simmons RL. Pancreatic trauma. A review. Surgery 1972; 71:27–43. Bach RD, Frey CF. Diagnosis and treatment of pancreatic trauma. Am J Surg 1971; 121:20–29. Donovan AJ, Turrill F, Berne CJ. Injuries of the pancreas from blunt trauma. Surg Clin North Am 1972; 52:649–665. Ryan S, Sandler A, Trenhaile S et al (1994) Pancreatic enzyme elevations after blunt trauma. Surgery 116:622–627 Lane MJ, Mindelnuz RE, Jeffrey RB (1996) Diagnosis of pancreatic injury after blunt abdominal trauma. Semin Ultrasound CT MR 17:177–182 Jeffrey RB Jr, Federle MP, Crass RA. Computed tomography of pancreatic trauma. Radiology 1983; 147:491–494.

AcknowledgementsDr. Stephan Anderson, BMCDr. Gillian Lieberman, BIDMC