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ABSTRACT: The purpose of this paper is to determine the relative frequency of multi-detector CT (MDCT) findings of pancreatic injury in blunt trauma and to determine their diagnostic accuracy in predicting main pancreatic duct injury. Fifty-three patients (31 male, 22 female; mean 44.1 years) with blunt trauma and admission MDCT findings suspicious for pancreatic injury or who underwent MDCT and had a discharge diagnosis of pancreatic trauma were included in this study. Two radiologists reviewed all images and recorded findings suspicious for pancreatic injury, which were subsequently compared to surgical findings to generate diagnostic accuracy. MDCT imaging findings suggestive of pancreatic injury included low attenuation peripancreatic fluid (n = 51), hyperattenuating peripancreatic fluid (n = 13), pancreatic contusion (n = 7), active hemorrhage (n = 2), and pancreatic laceration (n = 16). Diagnostic accuracy of the various imaging findings varied for diagnosing main duct injury; there were highly sensitive, nonspecific imaging findings such as the presence of low attenuation peripancreatic fluid (sensitivity, 100 %; specificity 4.9 %) as well as insensitive, specific findings such as visualizing a pancreatic laceration involving >50 % of the parenchymal width (sensitivity, 50 %; specificity, 95.1 %). In the setting of blunt abdominal trauma, MDCT imaging findings can be grouped into two categories for determining integrity of the main pancreatic duct: indirect, highly sensitive but nonspecific findings and direct, specific but insensitive findings. Awareness of the clinical implications of the various MDCT imaging findings of pancreatic trauma is useful in interpreting their significance.
Emergency Radiology 04/2013;
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ABSTRACT: The morbidity, mortality, and economic costs resulting from trauma in general, and blunt abdominal trauma in particular, are substantial. The "panscan" (computed tomographic [CT] examination of the head, neck, chest, abdomen, and pelvis) has become an essential element in the early evaluation and decision-making algorithm for hemodynamically stable patients who sustained abdominal trauma. CT has virtually replaced diagnostic peritoneal lavage for the detection of important injuries. Over the past decade, substantial hardware and software developments in CT technology, especially the introduction and refinement of multidetector scanners, have expanded the versatility of CT for examination of the polytrauma patient in multiple facets: higher spatial resolution, faster image acquisition and reconstruction, and improved patient safety (optimization of radiation delivery methods). In this article, the authors review the elements of multidetector CT technique that are currently relevant for evaluating blunt abdominal trauma and describe the most important CT signs of trauma in the various organs. Because conservative nonsurgical therapy is preferred for all but the most severe injuries affecting the solid viscera, the authors emphasize the CT findings that are indications for direct therapeutic intervention. ©RSNA, 2012.
Radiology 12/2012; 265(3):678-93. · 5.73 Impact Factor
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ABSTRACT: The purpose of this study was to evaluate the non-Gaussian behavior of diffusion related signal decay of the ex vivo murine liver tissues from a dietary model of hepatic fibrosis. To this end, a biexponential formalism was used to model high b-value diffusion imaging (up to 3500 s/mm(2)), the findings of which were correlated with liver histopathology and compared to a simple monoexponential model. The presence of a major, fast diffusing component and a minor, slow diffusing component was demonstrated. With increasing hepatic fibrosis, the fractional contribution of the fast diffusing component decreased, as did the diffusion coefficient of the fast diffusing component. Strong correlation between the degrees of liver fibrosis and a two-predictor regression model incorporating parameters of the biexponential model was found. Using Akaike's Information Criterion analyses, the biexponential model resulted in an improved fit of the high b-value diffusion data when compared to the monoexponential model.
Magnetic Resonance Imaging 08/2012; · 1.99 Impact Factor
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ABSTRACT: This study evaluated the effects of hepatic fibrosis on the multiexponential T(2) (MET(2) ) relaxation of ex vivo murine liver specimens using an 11.7 T MRI. This animal study was approved by the Institutional Animal Care and Use Committee. Eighteen male C57BL/6 mice were divided into control (n = 3) and experimental (n = 15) groups; the latter group was fed a 3,5-dicarbethoxy-1,4-dihydrocollidine-supplemented diet to induce hepatic fibrosis. Ex vivo liver specimens were imaged using an 11.7 T MRI scanner. A multi-echo spin-echo sequence was utilized for subsequent MET(2) analysis. Degrees of fibrosis were determined by a pathologist, as well as by digital image analysis. Scatterplot graphs comparing various features of the MET(2) signal decay with the degrees of fibrosis were generated, and correlation coefficients were calculated. Two distinct peaks of the MET(2) signal decay were identified in all liver specimens: a short T(2) component with a geometric mean T(2) (GMT(2) ) approximating 30 ms; and a long T(2) component with GMT(2) approximating 400 ms. Strong correlation was found between the degree of hepatic fibrosis and the amplitude of the short T(2) component, with a higher degrees of fibrosis associated with a lower amplitude. Moderate correlation was also found between hepatic fibrosis and the GMT(2) values of the long T(2) component, with higher degrees of fibrosis associated with lower GMT(2) values. The study of hepatic microenvironments using MET(2) analyses offers potential utility in the ongoing development of the noninvasive assessment of hepatic fibrosis using MRI. Copyright © 2012 John Wiley & Sons, Ltd.
NMR in Biomedicine 06/2012; · 3.21 Impact Factor
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Abdominal Imaging 04/2012; 35(3):287-287. · 1.73 Impact Factor
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ABSTRACT: Turbo spin echo (TSE) pulse sequences have been applied to estimate T(2) relaxation times in clinically feasible scan times. However, T(2) estimations using TSE pulse sequences has been shown to differ considerable from reference standard sequences due to several sources of error. The purpose of this work was to apply voxel-sensitivity formalism to correct for one such source of error introduced by differing phase encoding profile orders with dual-echo TSE pulse sequences. The American College of Radiology phantom and the brains of two healthy volunteers were imaged using dual-echo TSE as well as 32-echo spin-echo acquisitions and T(2) estimations from uncorrected and voxel-sensitivity formalism-corrected dual-echo TSE and 32-echo acquisitions were compared. In all regions of the brain and the majority of the analyses of the American College of Radiology phantom, voxel-sensitivity formalism correction resulted in considerable improvements in dual-echo TSE T(2) estimation compared with the 32-echo acquisition, with improvements in T(2) value accuracy ranging from 5.2% to 18.6%. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Magnetic Resonance in Medicine 02/2012; · 2.96 Impact Factor
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ABSTRACT: Delayed diagnosis of a bowel or mesenteric injury resulting in hollow viscus perforation leads to significant morbidity and mortality from hemorrhage, peritonitis, or abdominal sepsis. The timely diagnosis of bowel and mesenteric injuries requiring operative repair depends almost exclusively on their early detection by the radiologist on computed tomography examination, because the clinical signs and symptoms of these injuries are not specific and usually develop late. Therefore, the radiologist must be familiar with the often-subtle imaging findings of bowel and mesenteric injury that will allow for appropriate triage of a patient who has sustained blunt trauma to the abdomen or pelvis.
Radiologic Clinics of North America 01/2012; 50(1):123-36. · 2.59 Impact Factor
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ABSTRACT: This article discusses the critical protocol considerations in imaging patients with abdominal pain in the emergency department, specifically, the use of oral contrast, intravenous contrast, image postprocessing, and radiation dose. These considerations related to the use of computed tomography imaging of abdominal pain are reviewed in an evidence-based fashion.
Radiologic Clinics of North America 01/2012; 50(1):137-47. · 2.59 Impact Factor
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ABSTRACT: To evaluate the effects of hepatic fibrosis on ADC and T(2) values of ex vivo murine liver specimens imaged using 11.7 Tesla (T) MRI.
This animal study was IACUC approved. Seventeen male, C57BL/6 mice were divided into control (n = 2) and experimental groups (n = 15), the latter fed a 3, 5-dicarbethoxy-1, 4-dihydrocollidine (DDC) supplemented diet, inducing hepatic fibrosis. Ex vivo liver specimens were imaged using an 11.7T MRI scanner. Spin-echo pulsed field gradient and multi-echo spin-echo acquisitions were used to generate parametric ADC and T(2) maps, respectively. Degrees of fibrosis were determined by the evaluation of a pathologist as well as digital image analysis. Scatterplot graphs comparing ADC and T(2) to degrees of fibrosis were generated and correlation coefficients were calculated.
Strong correlation was found between degrees of hepatic fibrosis and ADC with higher degrees of fibrosis associated with lower hepatic ADC values. Moderate correlation between hepatic fibrosis and T(2) values was seen with higher degrees of fibrosis associated with lower T(2) values.
Inverse relationships between degrees of fibrosis and both ADC and T(2) are seen, highlighting the utility of these parameters in the ongoing development of an MRI methodology to quantify hepatic fibrosis.
Journal of Magnetic Resonance Imaging 01/2012; 35(1):140-6. · 2.70 Impact Factor
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ABSTRACT: To evaluate the image quality and clinical utility of a polytrauma computed tomographic (CT) protocol that integrates lower extremity CT angiography into multiphasic whole-body trauma CT by utilizing 64-detector CT and a single contrast material bolus.
This retrospective study was institutional review board approved and HIPAA compliant. Informed consent was waived. All patients who underwent CT angiography of the lower extremities integrated with multiphasic torso CT for trauma between May 2005 and September 2009 were included. Two hundred eighty-four patients met the inclusion criteria. The mechanism of trauma was blunt injury in 228 (80.3%) of 284 patients and penetrating in 56 (19.7%) of 284 patients. CT angiography encompassed the joints proximal and distal to the injured region, with scan delay fixed at 25 seconds. Two radiologists retrospectively reviewed all the extremity CT angiograms, noting the presence of vascular injury, and measured the attenuation in the lower extremity arteries. Arterial attenuation, in Hounsfield units, was measured at multiple vascular divisions, and CT angiographic results were compared with clinical outcome, and if available, repeat lower extremity CT angiographic, conventional angiographic, or surgical findings. Sensitivity and specificity with 95% confidence intervals were calculated.
Sixty-three arterial injuries were identified in 44 (15.5%) of 284 patients as follows: occlusion (n = 37), narrowing (n = 9), active extravasation (n = 14), pseudoaneurysm (n= 2), and arteriovenous fistula (n = 1). Three patients underwent conventional angiography after CT angiography. Seven patients underwent surgical therapy with all CT angiographic findings confirmed. There were no injuries subsequently identified in the subgroup with a negative result at CT angiography. Of the 864 vascular divisions in which attenuation was measured, 69 (8%) of 864 had a mean attenuation less than 150 HU.
Integration of lower extremity CT angiography into multiphasic whole-body trauma imaging is feasible, helps detect clinically relevant vascular injuries, and results in diagnostic image quality in the majority of patients.
Radiology 09/2011; 261(3):787-95. · 5.73 Impact Factor
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ABSTRACT: To evaluate the apparent diffusion coefficient (ADC) values of liver in a murine model of non-alcoholic steatohepatitis using 11.7 Tesla (T) MRI.
This animal study was IACUC approved. Seventeen male C57BL/6 mice were divided into control (n = 3) and experimental groups (n = 14) fed a methionine-deficient choline-deficient (MCD) diet to induce steatohepatitis. Livers underwent ex vivo diffusion-weighted MR imaging and ADC maps were calculated. A pathologist determined subjective scores of steatosis, classified from 0 to 3. Digital image analysis was used to determine percentage areas of steatosis. Graphs comparing ADC to subjective and digital image analysis (DIA) determinations of steatosis were plotted.
Subjective assessments of steatosis ranged up to values of 3 and DIA determined areas of steatosis to range up to approximately 16%. ADC values approximated 800 × 10(-6) mm(2) /s (range, 749-811 × 10(-6) mm(2) /s, mean 786 × 10(-6) mm(2) /s) in controls and 500 × 10(-6) mm(2) /s (range, 478-733 × 10(-6) mm(2) /s, mean 625 × 10(-6) mm(2) /s) in experimental mice. Moderate correlation between ADC and subjective scores of steatosis (R = -0.56) was observed. Strong correlation between ADC values and percentage areas of steatosis was between ADC values and percentage areas of steatosis was observed greater (R = -0.81) and very strong correlation was observed with the exclusion of a single outlying data point (R = -0.91).
Based on the comparison of ADC values and steatosis determinations by DIA, increasing degrees of steatosis are seen to result in decreased hepatic ADC values.
Journal of Magnetic Resonance Imaging 04/2011; 33(4):882-8. · 2.70 Impact Factor
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ABSTRACT: The purpose of this study is to evaluate how body habitus affects reader confidence in diagnosing acute appendicitis and appendiceal visualization using 64 MDCT technology with and without oral contrast. We conducted a HIPAA compliant, IRB approved study of adult patients presenting to the Emergency Department with nontraumatic abdominal pain. Subjects were randomized to two groups: 64 MDCT scans performed with oral and intravenous contrast or scans performed solely with intravenous contrast. Three radiologists established their confidence about the presence of appendicitis as well as recording whether the appendix was visualized. Reader confidence in diagnosing acute appendicitis was compared between the two groups for the three readers. The impact of patient BMI and estimated intra-abdominal fat on reader confidence in diagnosing appendicitis was determined. Finally, a comparison of the effect of BMI and intra-abdominal fat on appendiceal visualization between the two groups was carried out. Three hundred three patients were enrolled in this study. There was a statistically significant difference in confidence based on BMI for reader 2, group 1 in diagnosing appendicitis. No further statistically significant differences in reader confidence for diagnosing appendicitis based on BMI or intra-abdominal fat were identified. There was no influence of BMI or intra-abdominal fat on appendiceal visualization. Increasing BMI was seen to improve reader confidence for one of three readers in patients that received both oral and intravenous contrast. No further effects of BMI or intra-abdominal fat on confidence in diagnosing or excluding appendicitis were seen. Neither BMI nor intra-abdominal fat were seen to influence appendiceal visualization.
Emergency Radiology 05/2010; 17(6):445-53.
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ABSTRACT: Rapid assessment and diagnosis of traumatic arterial injuries are critical in the evaluation of acutely injured patients. CT angiograms (CTAs) have become common imaging methods in busy trauma centers. CTA has largely replaced digital subtraction angiography because of its speed, noninvasive nature, accuracy, and widespread availability. This article reviews the current use of multidetector CTA in trauma with attention to technique and protocol considerations, illustrates findings of many commonly encountered injuries, and discusses the clinical implications of vascular trauma throughout the body.
Radiologic Clinics of North America 03/2010; 48(2):423-38, ix-x. · 2.59 Impact Factor
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ABSTRACT: Ileal pouch-anal anastomosis (IPAA) surgery preserves fecal continence for improved quality of life in patients who require proctocolectomy for treatment of severe bowel diseases such as inflammatory disease and familial adenomatous polyposis. In IPAA surgery, an ileal reservoir, or pouch, is created and anastomosed to the anal canal. Awareness of the surgical technique and the postoperative anatomy of the IPAA is important to identify complications at computed tomography (CT), magnetic resonance (MR) imaging, and fluoroscopy. Complications include anastomotic leak, abscess, pouchitis, venous thrombus, pouch fistula, and stricture. Leaks from the blind end of the pouch and the pouch-anal anastomosis often result in pelvic abscesses, which may require ultrasonography- or CT-guided drainage; judicious catheter management can help improve clinical outcomes and avoid excessive imaging. Pouchitis may be identified by the presence of a thickened enhancing pouch wall and associated inflammatory changes and lymphadenopathy. The venous system must be scrutinized for thrombi secondary to surgical manipulation and sepsis. Fistulas are likely because of the presence of chronic inflammation or infection and may be seen at MR imaging, CT, or fluoroscopy. Strictures appear as areas of focal luminal narrowing with proximal dilatation, which can lead to obstruction. To avoid repeated exposure to radiation, MR imaging may be performed in patients who must undergo frequent imaging.
Radiographics 01/2010; 30(1):221-33. · 2.85 Impact Factor
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Stephan W Anderson,
Jorge A Soto,
Brian C Lucey,
Al Ozonoff,
Jacqueline D Jordan,
Jirair Ratevosian,
Andrew S Ulrich,
Niels K Rathlev,
Patricia M Mitchell,
Casey Rebholz,
James A Feldman,
James T Rhea
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ABSTRACT: The objective of our study was to compare the diagnostic accuracy of IV contrast-enhanced 64-MDCT with and without the use of oral contrast material in diagnosing appendicitis in patients with abdominal pain.
We conducted a randomized trial of a convenience sample of adult patients presenting to an urban academic emergency department with acute nontraumatic abdominal pain and clinical suspicion of appendicitis, diverticulitis, or small-bowel obstruction. Patients were enrolled between 8 am and 11 pm when research assistants were present. Consenting subjects were randomized into one of two groups: Group 1 subjects underwent 64-MDCT performed with oral and IV contrast media and group 2 subjects underwent 64-MDCT performed solely with IV contrast material. Three expert radiologists independently reviewed the CT examinations, evaluating for the presence of appendicitis. Each radiologist interpreted 202 examinations, ensuring that each examination was interpreted by two radiologists. Individual reader performance and a combined interpretation performance of the two readers assigned to each case were calculated. In cases of disagreement, the third reader was asked to deliver a tiebreaker interpretation to be used to calculate the combined reader performance. Final outcome was based on operative, clinical, and follow-up data. We compared radiologic diagnoses with clinical outcomes to calculate the diagnostic accuracy of CT in both groups.
Of the 303 patients enrolled, 151 patients (50%) were randomized to group 1 and the remaining 152 (50%) were randomized to group 2. The combined reader performance for the diagnosis of appendicitis in group 1 was a sensitivity of 100% (95% CI, 76.8-100%) and specificity of 97.1% (95% CI, 92.7-99.2%). The performance in group 2 was a sensitivity of 100% (73.5-100%) and specificity of 97.1% (92.9-99.2%).
Patients presenting with nontraumatic abdominal pain imaged using 64-MDCT with isotropic reformations had similar characteristics for the diagnosis of appendicitis when IV contrast material alone was used and when oral and IV contrast media were used.
American Journal of Roentgenology 11/2009; 193(5):1282-8. · 2.78 Impact Factor
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ABSTRACT: Anorectal injuries represent a relatively uncommon but clinically critical diagnosis in trauma. Anorectal injuries may be the result of penetrating injuries to the pelvis and perineal area as well as severe blunt traumatic injuries, often with pelvic fractures. The purpose of this review is to discuss injuries to the anorectal region sustained in trauma, specifically, in the application of multidetector computed tomography technology to these imaging diagnoses. An understanding of the pertinent anatomy is critical in characterization of these injuries using computed tomography (CT). Additionally, the subsequent clinical management decisions and how they are impacted by severity and location of injury in anorectal trauma is useful to the radiologist. This should serve to highlight the specific areas and injury distinctions that deserve our particular attention given possible changes in the ensuing management approaches. CT protocol issues including the use of oral, rectal, and intravenous contrast, as necessary, are relevant in maximizing the diagnostic accuracies of CT in anorectal trauma. This review serves to discuss and illustrate these pertinent issues, approaching penetrating and blunt trauma separately, with the emphasis on multidetector computed tomography in diagnosis.
Seminars in Ultrasound CT and MRI 01/2009; 29(6):472-82. · 1.24 Impact Factor
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ABSTRACT: To determine the feasibility and report clinical outcomes of upper extremity computed tomographic (CT) angiography with 64-section multidetector CT technology in the evaluation of patients sustaining penetrating trauma.
This HIPAA-compliant retrospective study was approved by the institutional review board and consent was waived. All adult trauma patients who sustained penetrating trauma to the upper extremity and who underwent CT angiography based on the recommendation of the attending trauma surgeon after the initial clinical examination were included. All studies were acquired with 64-section CT technology between April 2005 and September 2007 at our level I trauma center. Two radiologists in consensus retrospectively reviewed all the CT angiograms for evidence of arterial injury. Attenuation was measured with regions of interest placed within the arterial lumen of multiple segments of the upper extremity arteries. Hospital course and disposition were determined by reviewing the patients' medical records, with a mean follow-up of 33 days.
This study included 59 patients (54 men, five women; mean age, 27 years). Nineteen (32%) patients had the following arterial injuries at CT angiography: arterial occlusion (n = 7), arterial extravasation (n = 6), isolated pseudoaneurysm formation (n = 2), isolated focal stenosis (n = 2), occlusion and pseudoaneurysm formation (n = 1), and focal stenosis and pseudoaneurysm formation (n = 1). Of these 19 patients, seven underwent surgical treatment. Evaluation of the technical quality of the upper extremity angiograms demonstrated mean attenuation values of 244 HU. In 48 (81%) of 59 patients, mean attenuation values were higher than 200 HU, with four (7%) patients having mean attenuation values lower than 150 HU.
Upper extremity CT angiograms obtained with 64-section CT demonstrated adequate technical quality in the majority of patients and performed well clinically in patients with penetrating trauma.
Radiology 01/2009; 249(3):1064-73. · 5.73 Impact Factor
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ABSTRACT: The purpose of our study was to determine the clinical significance of the isolated finding of free intraperitoneal fluid on 64-MDCT in male patients who have undergone blunt trauma.
A retrospective study was performed of 669 consecutive male patients, ranging in age from 15 to 85 years, who underwent CT evaluation of the abdomen and pelvis at our level 1 trauma center over a 17-month period. Two radiologists evaluated the images for the presence of free intraperitoneal fluid and for an underlying cause. For patients with free intraperitoneal fluid, the mean attenuation and the size of the largest pocket of fluid on both portal venous and delayed phase images were measured for both those with and those without injury. For the patients who had free intraperitoneal fluid as an isolated finding, the electronic chart was reviewed to determine the clinical outcome, specifically whether these patients were observed, had short-interval follow-up imaging, or underwent exploratory laparotomy.
Forty-eight of the 669 patients (7.2%) had free intraperitoneal fluid. Twenty-nine (4.3%) of these patients had an identifiable solid organ, bowel, bladder, or pelvic injury to explain the free fluid. In the remaining 19 (2.8%) patients, free fluid was an isolated finding. The size of the largest collection of fluid was smaller for patients without identifiable injury on portal venous phase (1,236 vs 348 mm(2)) and delayed phase (1,325 vs 298 mm(2)) images (p = 0.0015 and p < 0.0001, respectively). Fluid in patients without identifiable injury was also shown to be less dense. A statistically significant difference between the mean attenuation coefficients of the fluid in the patients with and without injury was also found on both the portal venous phase (45.1 vs 13.1 HU, p < 0.0001) and delayed phase (45.6 vs 20.8 HU, p < 0.0001) images. All 19 patients without identifiable injury were admitted for observation and discharged without surgical intervention.
With 64 MDCT, the isolated finding of free intraperitoneal fluid in male patients who have undergone blunt trauma is seen in approximately 3% of patients. The size and mean attenuation coefficient measurements may add useful information regarding the clinical management of these patients, suggesting that small amounts of low-attenuation free fluid, in the absence of identifiable injury, may have no significant clinical implications.
American Journal of Roentgenology 12/2008; 191(6):1821-6. · 2.78 Impact Factor
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ABSTRACT: To retrospectively evaluate the sensitivity and specificity of 64-detector computed tomography (CT) in the portal venous phase by using transverse images and both multiplanar and minimum intensity reformations for the detection of biliary duct narrowing and choledocholithiasis, with magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) as the reference standard.
Approval from institutional review board was obtained for this HIPAA-compliant retrospective study; informed consent was waived. The study included all patients (42 men, 52 women; mean age, 61 years) who underwent abdominal 64-detector CT within 2 months of MRCP and/or ERCP. All patients underwent portal venous phase intravenous contrast material-enhanced abdominal CT. Sixty-one patients underwent MRCP and 54 patients underwent ERCP (21 patients underwent both). Two radiologists, blinded to the reference standard, independently evaluated the CT images, including multiplanar and minimum intensity reformations, for biliary duct narrowing and choledocholithiasis. Standard of reference examinations were used to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).
Twenty-three (24%) of 94 patients had a biliary duct narrowing at reference examinations. For detecting biliary duct narrowing, observer 1 had a sensitivity of 78.2%, specificity of 100%, PPV of 100%, and NPV of 93.4% and observer 2 had a sensitivity of 69.6%, specificity of 100%, PPV of 100%, and NPV of 91.0%. In 18 (19%) of 94 patients, choledocholithiasis was detected at reference examinations. For detecting choledocholithiasis, observer 1 had a sensitivity of 77.8%, specificity of 96.1%, PPV of 82.4%, and NPV of 94.8% and observer 2 had a sensitivity of 72.2%, specificity of 96.1%, PPV of 81.2%, and NPV of 93.6%.
Portal venous phase multidetector CT images are highly specific and moderately sensitive for the detection of biliary duct narrowing and choledocholithiasis.
Radiology 06/2008; 247(2):418-27. · 5.73 Impact Factor
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ABSTRACT: To retrospectively evaluate the integration of pelvic computed tomographic (CT) angiography into the thoracoabdominal CT examination of blunt trauma by using 64-detector row CT to differentiate active arterial from active venous hemorrhage.
This study was institutional review board approved and HIPAA compliant; the requirement for informed patient consent was waived. Fifty-three patients (30 male, 23 female; mean age, 42 years) with multiple blunt trauma underwent pelvic CT angiography with 64-detector row CT at admission. Arterial phase and portal venous phase pelvic CT angiograms were evaluated for evidence of vascular injury. In patients with active extravasation, the size of the hemorrhaging area was measured on arterial, portal venous, and delayed phase images. The Fisher exact test was used to correlate presence of vascular injury with subsequent clinical management. The Wilcoxon rank sum test was used to test the association between size of active hemorrhage during the vascular enhancement phases and subsequent clinical outcome. Finally, the Fisher exact test was used to correlate presence of vascular injury with severity of osseous injury.
At pelvic CT angiography, 21 of the 53 patients had evidence of vascular injury: 10 isolated active arterial extravasations, three isolated arterial occlusions, three cases of both arterial extravasation and occlusion, two cases of arterial and venous extravasations, and three isolated venous extravasations. Eleven of the 21 patients also underwent conventional angiography, with subsequent embolization performed in seven of these 11 patients. The remaining 10 patients were successfully treated conservatively. When the foci of active arterial extravasation were compared on arterial, portal venous, and delayed phase images, the mean areas of hemorrhage across all three phases were larger in patients who required conventional angiography than in those successfully treated with conservative management.
With use of 64-detector row scanning, pelvic CT angiography was successfully integrated into the authors' CT protocols and enabled differentiation between active arterial and active venous hemorrhage, which may influence clinical management.
Radiology 03/2008; 246(2):410-9. · 5.73 Impact Factor
