1) Appreciate the rationale for Whole Body Imaging in assessing the polytrauma patient. 2) Compare advantages of whole body versus segmental MDCT protocol. 3) Demonstrate significance of arterial and portal venous phase imaging in the setting blunt abdominal trauma (BAT), and the role of whole body imaging in the setting of BAT. 4) Understand and review strategies for reducing radiation exposure. 5) Discuss strategies and techniques for optimization of whole body imaging protocols in the trauma setting. 6) Discuss Future Directions to allow bridging of anatomy and function.

Traumatic bowel and mesenteric injury (TBMI) is an uncommon entity that can be lethal if not detected and treated in a timely manner. The purpose of our study was to evaluate the diagnostic accuracy of 64MDCT for the detection of TBMI in patients at our level 1 trauma centre.

We used our hospital's trauma registry to identify patients with a diagnosis of TBMI from January 1, 2006 to June 30, 2013. Only patients who had a 64MDCT scan at presentation and subsequently underwent laparotomy/laparoscopy were included in the study cohort. Using the surgical findings as the gold standard, the accuracy of prospective radiology reports was analyzed.

Of the 4781 trauma patients who presented to our institution, 44(0.9%) had surgically proven TBMI. 22/44 were excluded as they did not have MDCT before surgery. The study cohort consisted of 14 males and 8 females with a median age of 41.5 years and a median Injury Severity Score of 27. 17/22 had blunt trauma and 5/22 had penetrating injury. A correct preoperative imaging diagnosis of TBMI was made in 14/22 of patients. The overall sensitivity of the radiology reports was 63.6% (95% CI: 41-82%), specificity was 79.6 % (95% CI: 67-89%), PPV was 53.9% (95% CI: 33 -73 %) and NPV was 85.5% ( 95% CI: 73-94 %). The accuracy was 90.5%. However, only 59 % (10/17) of patients with blunt injury had a correct preoperative diagnosis. Review of the findings demonstrated that majority of patients with missed blunt TBMI (5/7) demonstrated only indirect signs of injury.

The detection of TBMI in trauma patients on 64MDCT can be improved, especially in patients presenting with blunt injury. Missed cases in this population occurred because the possibility of TBMI was not considered despite the presence of indirect imaging signs.

The prospective diagnosis of TBMI remains challenging despite advances in CT technology and widespread use of 64MDCT.

To evaluate how the implementation of an institutional triaging algorithm impacted the utilization of MDCT imaging of the abdomen and pelvis at a level one trauma center.

This retrospective HIPAA compliant study was IRB approved. Informed consent was waived. All adult patients admitted for abdominal trauma from 1/1/06-12/31/13 were included in this study. The total number of abdomino-pelvic CT scans acquired, mean injury severity score (ISS) and percentage of trauma scans with positive findings per year were recorded. We then determined the impact that a triaging clinical algorithm, introduced in January 2009, had on these parameters. Patients were divided into two groups: before the implementation of this triaging algorithm (2006-2009) and after (2010-2013). The unpaired t-test and Fisher's exact test were used to compare the two groups for significant differences in the ISS and percentage of positive CT scans, respectively.

The number of annual trauma admissions and the percentage of these patients who received abdomino-pelvic CT scans were: 2006 (2122/71%), 2007 (2234/74%), 2008 (2231/71%), 2009 (2033/60%), 2010 (2167/44%), 2011 (1929/43%), 2012 (1923/36%), and 2013 (1729/39%). The mean ISS and percentage of positive scans for the same time period were: 2006 (9/18%), 2007 (9/19%), 2008 (8/19%), 2009 (9/17%), 2010 (10/20%), 2011 (10/24%), 2012 (11/22%) and 2013(9/20%). Patients admitted after the implementation of the clinical trauma algorithms had a significantly higher mean ISS and a significantly higher percentage of positive CT scans (p<0.0001; p<0.0002, respectively).

The implementation of a clinical algorithm at our level one trauma center resulted in decreased utilization of trauma CT scanning. Our analysis suggests that this clinical algorithm can be used successfully to select patients who require CT imaging in the trauma setting.

In the trauma setting, institutional algorithms can be implemented to prevent unnecessary imaging of patients in a nationwide effort to reduce radiation exposure and hospital costs.

To quantify the risks and benefits of changing CT protocol in the ED/trauma setting to include an arterial phase CT of the abdomen.

Several recent studies have demonstrated increased sensitivity for identifying contained splenic vascular injury (ie pseudoaneurysm and arteriovenous fistula formation) in trauma patients by the addition of arterial-phase CT abdominal imaging. However, the overall risk-benefit ratio is not known. Using published data, we quantified the number of previously undiagnosed cases of contained splenic vascular injury in trauma patients age 15 and older, as well as the number of patients for whom management would change and the number of new cancer cases induced by the increased radiation dose. During sensitivity analysis, supplemental data from a level 1 trauma center was used to help identify patient subgroups with a more favorable risk-benefit ratio.

The number needed to scan to identify one new case of contained vascular injury was 182, to change management in one patient was 255, and to induce one new cancer was 3,584. Increased dose length product (DLP) resulted in higher cancer induction risk, but this risk was relatively small and did not result in more cancer cases caused than new vascular injury cases detected over a range of normal DLP values. Analysis using the age distribution of trauma patients at our institution and an age-dependent cancer induction rate did not significantly change results. Pending results include additional analysis utilizing data from a level 1 trauma center, including stratification by gender, mechanism of injury (blunt versus penetrating) and severity of injury (level 1 trauma, level 2 trauma, or overall population).

The addition of an arterial phase CT abdomen to a trauma protocol for the assessment of contained splenic vascular injury has a favorable risk-benefit ratio across a range of typical DLP values.

The addition of an arterial phase CT abdomen to a trauma protocol for the assessment of contained splenic vascular injury has a favorable risk-benefit ratio across a range of typical DLP values.

1) Demonstrate the spectrum of traumatic aortic injury: typical, atypical and minimal injury. 2) Discuss the role of imaging and tratment of traumatic aortic injury.

To determine if the CT Severity Index predicts the need for subsequent splenectomy in patients who undergo splenic artery embolization as the primary therapy of severe blunt splenic injuries.

This retrospective study was HIPAA compliant and IRB approved with waiver of informed consent. Twenty-five adult patients with blunt splenic trauma evaluated with abdominal CT between 1/1/2006 and 1/31/2013 who subsequently underwent and survived splenic artery embolization were included. The study population included 19 male and 6 female patients. Two radiologists retrospectively and independently reviewed the CT images and classified splenic injuries using the CT Severity Index: intraperitoneal active extravasation (grade 4b), intrasplenic vascular injury (grade 4a) and no vascular injury (grades 2 or 3). Another investigator reviewed the electronic medical records and documented whether or not each patient required splenectomy for definitive therapy. Two-tailed Fisher's exact test was used to evaluate the association between the admission CT severity index and the success rate of splenic embolization as primary therapy (defined by stable patient discharge without the need for surgical splenectomy).

CT severity Indices: grade 4b (n=13), grade 4a (n=9), grade 3 (n=2) and grade 2 (n=1). Of the 25 patients, 21 recovered with no additional intervention and were determined to have a successful outcome: Ten with grade 4b, eight with grade 4a and three with grades 2 or 3. Four patients required splenectomy and the embolization procedure was deemed a failure: three with grade 4b and one with grade 4a. Thus, 10/13 (77%) patients with grade 4b and 11/12 (92%) patients with grade 2 to 4a injuries had successful embolization procedures as primary therapy. This difference was not statistically significant (p >.05).

The majority of patients with blunt splenic injury can be treated with arterial embolization and will not require a splenectomy. This includes patients with intraperitoneal active extravasation (CT severity index grade 4b).

Embolization can be used to successfully treat all types of vascular injuries in the spleen caused by blunt trauma, including free extravasation of contrast-enhanced blood into the peritoneal cavity.

1) To discuss the role of MDCT in patients with blunt and penetrating diaphragmatic injuries. 2) Review the MDCT findings of diaphragmatic injuries. 3) Describe potential pitfalls.

Diaphragmatic Injuries remain a challenging diagnosis with potential catastrophic delayed complications. A high degree of suspicion in every case of severe blunt thoracoabdominal trauma or penetrating thoracoabdominal injury is essential. This presentation will provide a practical tutorial for radiologists hoping to improve their interpretive accuracy for both blunt and penetrating DIs. The CT signs of diaphragmatic injuries will be explained. A number of instructive cases will be presented, including frequent diagnostic pitfalls.

Diaphragmatic injuries have a marked impact on the management and prognosis of trauma patients. Motion artifacts may obscure diaphragm injuries during CT of trauma patients with low Glascow Coma Scale (GCS) scores or those who are intubated and ventilated. CT acquisition times are dramatically reduced by using dual source ultra-high pitch (DS-UHP) as compared with conventional single source (SS) protocols. The purpose of this study was to evaluate diaphragmatic motion on simultaneously acquired DS-UHP and SS CT scans in trauma patients.

Seventy-five consecutive trauma patients who presented to a level one trauma centre over a 6 month period scanned with a standardized trauma protocol including both DS-UHP chest (pitch = 1.7-3.2) and SS abdominal CT scans (pitch =0.6) were reviewed retrospectively. Subjective analysis of diaphragmatic motion was performed in consensus by two readers using a 4 point likert scale in 7 regions of the diaphragm on coronal 3mm and axial 1mm-3mm slices. An overall confidence score to exclude a diaphragmatic tear based on all coronal and axial images available was also determined (1 to 10, 10 being completely confident and 1 being impossible to exclude). Wilcoxon Rank Sum tests were used for statistical analysis and p < 0.05 was considered significant.

The mean overall confidence score for the DS-UHP was 9.85, which was significantly better than the mean score of 7.66 for SS images (p < 0.0001). The scores for diaphragmatic motion on coronal and axial images were significantly better for DS-UHP images in all areas when compared individually (p < 0.0001). Additionally, utilizing the overall coronal image scores, the subjective diaphragmatic motion was significantly less in the DS-UHP images than the SS images (p < 0.0001).

Ultra high-pitch is advantageous as it allows for better evaluation of diaphragmatic structures by minimizing motion artifacts on images of freely breathing trauma patients.

An ultra high-pitch dual source mode is valuable in trauma patients who are unable to breath-hold as it allows minimization of motion artifacts of the diaphragm as compared with conventional single source reconstructions.

Traumatic diaphragmatic rupture (DR) is an uncommon injury that can be lethal if not detected and treated in a timely manner. The purpose of our study was to evaluate the diagnostic accuracy of 64MDCT for the detection of DR in patients at our level 1 trauma centre.

We used our hospital's trauma registry to identify patients with a diagnosis of DR from January 1, 2008 to December 31, 2012. Only patients who had a 64MDCT scan at presentation and subsequently underwent laparotomy/laparoscopy were included in the study cohort. Using the surgical findings as the gold standard, the accuracy of prospective radiology reports was analyzed.

Of the 3225 trauma patients presented to our institution, 38(1.2%) had a DR. Fourteen of the 38 were excluded as they did not have MDCT pre-surgery. The cohort consisted of 20 males and 4 females with a median age of 34.5 years and a median Injury Severity Score of 26. Fifteen had a blunt trauma while 9 had a penetrating injury (PI). The overall sensitivity of the radiology reports was 66.7% (95% CI: 44.7- 84.3%), specificity was 100% (95% CI: 94-100%), PPV was 100% (95% CI: 79.2-100%) and NPV was 88.4 (95% CI: 78.4-94.8%) . The accuracy was 91%. However, only 3/9 with PI (33%) had a correct preoperative diagnosis. Most of the missed cases (4/6) had only indirect signs of injury.

The detection of DR in trauma patients on 64MDCT can be improved, especially in patients presenting with PI. Most missed cases occurred because the possibility of DR was not raised despite the presence of indirect evidence.

The prospective diagnosis of DR remains challenging despite advances in CT technology and widespread use of 64MDCT.

1) Describe the optimal CTA imaging protocol for the evaluation of suspected peripheral vascular injuries. 2) Identify the various imaging manifestations of peripheral vascular injuries. 3) Recognize CTA limitations and pitfalls in the diagnosis of peripheral vascular injuries. 4) Recognize when further evaluation with catheter angiography or surgical exploration are required.

http://media.rsna.org/media/abstract/2014/14002056/VSER51-11 sec.pdf

This study examined how the constellation of radiological findings seen in hypovolemic shock complex on a Multi-Detector Computed Tomography (MDCT) scan correlate with survival of polytrauma patients.

A retrospective study design was undertaken examining patients involved in severe blunt trauma with an Injury Severity Score (ISS) >= 16 who were admitted to the emergency department (ED) at a Level I Trauma Center between July 2011 and June 2013. Patients underwent a standardized multi-phasic whole body MDCT protocol obtained from a single CT scanner located within the ED. Radiological findings of hypovolemic shock were identified from the scan including vascular and non-vascular findings. Radiological variables were correlated with clinical and 30-day mortality data.

50 patients were identified, of which 17 died and 33 survived their injuries. The mortality cohort had lower Glasgow Coma Score (GCS) (6.0 vs. 11.9, p<0.0001) and higher ISS (43.6 vs. 31.7, p=0.002), and lower TRISS, a measure of predicted survival (23.1% vs. 70.0%, p=0.05). The mortality group had lower mean Hb (116.2 vs. 127.2 g/L, p=0.03) and higher rates of transfusion (90% vs. 47%, p=0.05). The mortality cohort demonstrated greater enhancement of the left ventricular chamber in arterial phase (330.2 vs. 261.7 HU, p=0.01). The diameter of the abdominal aorta and IVC were smaller (14.8 vs. 16.4mm, p=0.04; 12.5 vs. 15.3mm, p=0.04). The renal medulla and spleen showed lower enhancement (133.4 vs. 175.5 HU, p=0.0006, 102.7 vs. 123.4 HU, p=0.01). No statistical differences were shown with respects to myocardial, adrenal, liver, gallbladder wall, or pancreatic enhancement. No difference was seen in pulmonary vein diameter. No differences were seen with respects to the presence of shock bowel, free fluid, or halo sign around the IVC.

Small caliber of the great vessels and decrease perfusion of the spleen and renal medulla were seen in the mortality group. Contrast enhancement of the left ventricular chamber was greater in the mortality cohort which may be a novel indictor of low cardiac output or increase in systemic vascular resistance in the context of hypovolemic shock.

Quantitative analysis of left ventricular chamber enhancement, diameter of the great vessels, and spleen and renal medulla enhancement on multi-phasic whole body MDCT scans may identify polytrauma patients at risk of death.

The Systemic Inflammatory Response Syndrome (SIRS) can lead to organ failure and death in multiply injured patients (MIPs). SIRS results primarily from an immune response to endogenous molecules thought to be liberated from damaged tissue. However, it is not known how the magnitude of tissue injury affects systemic inflammation and organ dysfunction. It is plausible that certain tissues are more prone to release of inflammatory mediators leading to SIRS, and that the magnitude of soft tissue injury may correspond with the degree of systemic inflammation and subsequent organ dysfunction. The purpose of this study was to determine how the total volume of soft tissue damage, as quantified on admission whole body CT scan, correlated with the magnitude of inflammation and organ dysfunction in MIPs.

Clinical data from 51 MIPs (ISS ≥ 18, age 18-65), admitted to the ICU for a minimum of 6 days, were used to calculate daily SIRS scores (0 to 4) and daily Sequential Organ Functional Assessment scores (SOFA; 0 - 24). The Soft Tissue Damage Volume Score (STDVS) was calculated by combining the volumetric measurements of all soft tissue injuries (extravascular blood products) in each patient as measured on admission whole body CT scans. Regression analyses evaluated correlations between STDVS and both SIRS and SOFA scores.

The results demonstrate two distinct patient populations; those at High Risk and those at Low Risk for subsequent inflammation and organ dysfunction. The average SIRS score vs STDVS slope was 10.5x higher in high risk patients (Fig 1, p<0.01) and average SOFA scores vs STDVS slope was 6.14X higher in high risk patients (, p<0.01). There is a linear relationship between the STDVS and the SIRS and SOFA scores for these two patient populations.

The magnitude of systemic inflammation and organ dysfunction is a function of STDVS. These results demonstrate a dichotomous response of how MIPs tolerate soft tissue damage, suggesting that some patients are at higher risk of systemic inflammation than others.

STDVS as calculated on admission CT may serve as a potential clinical tool for predicting systemic inflammation and organ dysfunction during the recovery process. Further investigations are required to elucidate the underlying pathophysiologic pathways for how soft tissue damage causes inflammation and organ dysfunction in MIPs.

Physicians often order both a three-view study of the hand and four-view study of the ipsilateral wrist following hand and/or wrist injury. Because hand radiographs include visualization of the carpus, we set out to determine whether a modified study using fewer wrist radiographs performs comparably to the traditional hand and wrist series in the evaluation of acute hand and wrist abnormalities.

This retrospective study was approved by the institutional review board, and the need to obtain informed consent was waived. Two hundred forty patients (50% male; age range 18-92y) with unilateral three-view hand (posteroanterior, oblique, and lateral) and four-view wrist (posteroanterior, oblique, lateral, and ulnar deviation) radiographs obtained concurrently in the emergency setting were included in this study. Four experienced emergency radiologists, blinded to the original report and clinical records, interpreted the original seven images. The patients' radiographs were then recombined to include only the three hand images and a single ulnar deviated wrist view. These were interpreted by the same radiologists following an eight week delay and in random sequence to reduce memory bias. Two radiologists independently evaluated each patient's studies. Data analysis was performed using kappa statistics to measure agreement between the seven- and four-view image interpretations.

A total of 479 reports were generated in each of the seven- and four-view image sets, with 142 (29.6%) of the seven-view and 125 (26.1%) of the four-view reports conveying certain or suspected acute osseous findings. Statistical analysis yielded an average inter-method kappa coefficient of 0.818 for the four radiologists, which represents strong agreement between the seven- and four-view interpretations.

The modified four-view hand and wrist radiographic series produces diagnostic results comparable to the traditional hand and wrist series in the acute clinical setting.

A modified four-view hand and wrist radiographic study is effective for assessing acute hand and wrist injury while reducing cost, time, and radiation dose.