Rapid imaging protocol in trauma: a whole-body dual-source CT scan

Trauma Computed Tomography in the Modern Era: Not Always Quick and Safe

BACKGROUND

Computed tomography (CT) has emerged as the diagnostic modality of choice in trauma patients. Recent studies suggest its use in hemodynamically unstable patients is safe and potentially lifesaving; however, the incidence of adverse events (AE) during the trauma CT scanning process remains unknown.

STUDY DESIGN

Over a 6-month period at a Level 1 trauma center, data on patients undergoing trauma CT (whole-body CT (WBCT) +/- additional CT studies) were prospectively collected. All patients requiring a trauma team activation (TTA) were included. Adverse events and specific time intervals were recorded from the time of TTA notification to the time of return to the resuscitation bay from the CT suite.

RESULTS

Of the 94 consecutive patients included in the study, 47.9% experienced 1 or more AE. Median duration away from the resuscitation bay for all patients was 24 minutes. Patients with AE spent a significantly longer time away from the resuscitation bay and had longer scan times. Vasopressor support and ongoing transfusion requirement at the time of CT scanning were associated with AE.

CONCLUSION

Adverse events of varying clinical significance occur frequently in patients undergoing emergent trauma CT. A standard trauma CT protocol could improve the efficiency and safety of the scanning process.

Deep learning reconstruction for contrast-enhanced CT of the upper abdomen: similar image quality with lower radiation dose in direct comparison with iterative reconstruction

OBJECTIVE

To evaluate the effect of a commercial deep learning algorithm on the image quality of chest CT, focusing on the upper abdomen.

METHODS

One hundred consecutive patients who simultaneously underwent contrast-enhanced chest and abdominal CT were collected. The radiation dose was optimized for each scan (mean CTDI_vol: chest CT, 3.19 ± 1.53 mGy; abdominal CT, 7.10 ± 1.88 mGy). Three image sets were collected: chest CT reconstructed with an adaptive statistical iterative reconstruction (ASiR-CHT; 50% blending), chest CT with a deep learning algorithm (DLIR-CHT), and abdominal CT with ASiR (ASiR-ABD; 40% blending). Afterwards, the images covering the upper abdomen were extracted, and image noise, the signal-to-noise ratio (SNR), and the contrast-to-noise ratio (CNR) were measured. For subjective evaluation, three radiologists independently assessed noise, spatial resolution, presence of artifacts, and overall image quality. Additionally, readers selected the most preferable reconstruction technique among three image sets for each case.

RESULTS

The average measured noise for DLIR-CHT, ASiR-CHT, and ASiR-ABD was 8.01 ± 2.81, 14.8 ± 2.56, and 12.3 ± 2.28, respectively (p < .001). Deep learning-based image reconstruction (DLIR) also showed the best SNR and CNR (p < .001). However, in the subjective analysis, ASiR-ABD showed less subjective noise than DLIR (2.94 ± 0.23 vs. 2.87 ± 0.26; p < .001), while DLIR showed better spatial resolution (2.60 ± 0.34 vs. 2.44 ± 0.31; p = .02). ASiR-ABD showed a better overall image quality (p = .001), but two of the three readers preferred DLIR more frequently.

CONCLUSION

With < 50% of the radiation dose, DLIR chest CT showed comparable image quality in the upper abdomen to that of dedicated abdominal CT and was preferred by most readers.

KEY POINTS

• With < 50% radiation dose, a deep learning algorithm applied to contrast-enhanced chest CT exhibited better image noise and signal-to-noise ratio than standard abdominal CT with the ASiR technique. • Pooled readers mostly preferred deep learning algorithm-reconstructed contrast-enhanced chest CT reconstructed using a standard ASiR-reconstructed abdominal CT. • Reconstruction algorithm-induced distortion artifacts were more frequently observed on deep learning algorithm-reconstructed images, but diagnostic difficulty was reported in only 0.3% of cases.

European Society of Emergency Radiology: guideline on radiological polytrauma imaging and service (short version)

BACKGROUND

Although some national recommendations for the role of radiology in a polytrauma service exist, there are no European guidelines to date. Additionally, for many interdisciplinary guidelines, radiology tends to be under-represented. These factors motivated the European Society of Emergency Radiology (ESER) to develop radiologically-centred polytrauma guidelines.

RESULTS

Evidence-based decisions were made on 68 individual aspects of polytrauma imaging at two ESER consensus conferences. For severely injured patients, whole-body CT (WBCT) has been shown to significantly reduce mortality when compared to targeted, selective CT. However, this advantage must be balanced against the radiation risk of performing more WBCTs, especially in less severely injured patients. For this reason, we recommend a second lower dose WBCT protocol as an alternative in certain clinical scenarios. The ESER Guideline on Radiological Polytrauma Imaging and Service is published in two versions: a full version (download from the ESER homepage, https://www.eser-society.org ) and a short version also covering all recommendations (this article).

CONCLUSIONS

Once a patient has been accurately classified as polytrauma, each institution should be able to choose from at least two WBCT protocols. One protocol should be optimised regarding time and precision, and is already used by most institutions (variant A). The second protocol should be dose reduced and used for clinically stable and oriented patients who nonetheless require a CT because the history suggests possible serious injury (variant B). Reading, interpretation and communication of the report should be structured clinically following the ABCDE format, i.e. diagnose first what kills first.

Incidence and clinical impact of lower extremity vascular injuries in the setting of whole body computed tomography for trauma

PURPOSE

The aims of this study are to determine the incidence of lower extremity fractures and/or vascular injuries in the setting of whole body computed tomography (WBCT) for trauma and to determine lower extremity injury outcomes in this patient population.

METHODS

This is a retrospective observational study performed at a large urban Level 1 trauma center. Our institutional trauma registry was queried for patients who were evaluated with WBCT and lower extremity CT angiography (CTA) as a part of their initial imaging evaluation over a 43-month period. Patients with lower extremity fractures and/or vascular injuries were identified. Those patients with both lower extremity vascular injury and fracture were then analyzed to determine the physical relationship of the fracture to the vascular injury. Physical exam findings were extracted from the medical record. Interventions and long-term outcomes were determined from the medical record.

RESULTS

A total of 370 patients met the inclusion criteria, with 98% experiencing blunt trauma. Of these, 290 (78.4%) were positive for lower extremity injury, including 266 (71.9%) with isolated fractures, 2 (0.6%) with isolated vascular injury, and 22 (5.9%) with vascular injury associated with long bone fracture. Of the 22 patients with combined fracture and vascular injury, 8 received vascular intervention and 10 had long-term complications as a result of their injuries. Physical exam findings were insufficient to diagnose 57% of the vascular injuries.

CONCLUSIONS

The inclusion of lower extremity CTA as part of a WBCT imaging exam for trauma allows for the identification of vascular injuries that otherwise may have gone undetected or resulted in delayed diagnosis. Clinically occult lower extremity vascular injuries may be associated with poor outcomes.

Mass casualty incidents-are you ready? A major incident planning template for diagnostic radiology

Mass casualty incidents (MCIs) create a large number of casualties in a short period of time. Diagnostic radiology plays an important role in major incident responses but is often underrepresented during major incident planning (MIP) and simulation. Surveys suggest radiologists are unfamiliar with their role during an MCI. We aimed to identify key topics for radiology MIP, familiarize radiologists with their role during an MCI and identify areas for future research. The terms "radiology" and "mass casualty incident" were entered into the advanced search builder on PubMed. Abstracts from this primary search were reviewed and papers selected for inclusion. Additional studies of interest were identified upon review of reference sections of relevant articles and from the related article tab on PubMed. MCI and trauma guidelines were reviewed. Key factors that caused issues during prior MCIs were identified including staff alert mechanisms, patient identification strategies, patient tracking, scan ordering and result communication. Limitations of local imaging resources and capacity should be identified and inform plans for the utilization of diagnostic radiology in the MCI setting. Simulation can help identify areas for improvement and familiarize staff with their roles. Further development of reliable MCI alert technology and patient identification strategies are needed as well as prospective validation of trauma CT selection criteria to identify patients who will benefit most from CT. Radiology should take part in MIP to address key issues encountered during prior MCIs and in MCI simulation to optimize major incident response.

The influence of arm positions on abdominal image quality of whole-body computed tomography in trauma: systematic review

PURPOSE

Whole-body computed tomography (WBCT) is the standard diagnostic method for evaluating polytrauma patients. When patients are unable to elevate their arms, the arms are placed along the body, which affects the image quality negatively. Aim of this systematic review is to evaluate the influence of below the shoulder arm positions on image quality of WBCT.

METHODS

Literature in PubMed and Scopus databases was systematically searched. Results of the papers were stratified into 4 categories: arms elevated, 1 arm up 1 arm down, arms ventrally supported, arms along the body. A qualitative analysis was performed on subjective image quality and a quantitative analysis on objective quality (image noise).

RESULTS

Eight studies were included with 1421 participants. Various studies reported significantly higher quality scores with arms elevated, compared to arms along the body. Significant differences in objective image quality were found between the arms elevated and the arms ventrally on support group. The arms ventrally supported group had a significantly higher image quality than the arms along the body group. A statistically significant difference was found in objective image quality between the 1 arm up 1 arm down and arms along the body group. No preferential below the shoulders position could be identified.

CONCLUSION

Positioning the arms alongside the body results in a poor image quality. Placing the arms on a pillow ventrally to the chest improves image quality. Interestingly, asymmetrical arm positioning has potential to improve the image quality for patients that are unable to elevate the arms.

Rare constellation of abdominal vascular injuries in blunt trauma: Left gastric artery pseudoaneurysms and dissection

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Traumatic visceral artery pseudoaneurysms and dissections are typically secondary to penetrating trauma involving splenic or hepatic vessels.

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Solitary left gastric pseudoaneurysm and dissection in blunt trauma are rare, and best recognized using multi-detector multiphase CTA.

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Pseudoaneurysms measuring less than 2.0 cm without symptoms of persistent abdominal pain or peritoneal signs can be managed conservatively.

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Conservative management involves close observation, treatment with antithrombotic agents, and optimization of medical comorbidities.

Introduction

Abdominal visceral artery pseudoaneurysms and dissections in blunt trauma are uncommon, however, solitary vascular injury of the left gastric artery and development of multifocal dissections are extremely rare with only 5 reported cases in the literature.

Presentation of case

A 79-year-old male presents two days after a motor boating incident in profound hemorrhagic shock. Subsequent CT imaging revealed moderate hemoperitoneum, two pseudoaneurysms of the left gastric artery measuring 6 mm and 9 mm, as well as attenuation of the artery in keeping with a focal dissection and intramural thrombus, and no active extravasation. After stabilization with blood product resuscitation, he was managed conservatively with administration of ASA and close monitoring.

Conclusion

Abdominal visceral artery vascular injuries in blunt trauma can be managed safely with close monitoring, antithrombotic agent, and medical co-morbidity optimization. Instability or worsening/ persistent symptoms should be considered for endovascular treatment or surgical ligation Further research and reporting of management approaches are required.

What Are the Expected Findings on Follow-up Computed Tomography Angiogram in Post-traumatic Patients With Blunt Cerebrovascular Injury?

PURPOSE

Blunt cerebrovascular injury (BCVI) is a rare but potentially devastating diagnosis. Our study establishes the temporal changes and findings on follow-up imaging.

METHODS

For this retrospective, institutional review board-approved study, the hospital trauma registry was queried for all severely injured polytrauma patients who underwent computed tomography angiogram (CTA) scans in the emergency department between January 1, 2010, and December 31, 2016, with injury severity score ≥16, yielding 3747 patients. A total of 128 patients had a follow-up CTA for BCVI. The grade, location, and outcomes of injuries on follow-up imaging were studied.

RESULTS

A vehicular collision was the most common mechanism of injury (75%). The majority of patients (61%) had a Glasgow Coma Scale of 10-15. Vertebral fractures were the most common associated injury (57%). The overall incidence of BCVI in our study population was 4.8%. On the initial CTA, 50% of injuries were grade 1, 25.4% were grade 2, 7% were grade 3, 17% were grade 4, and 0.6% were grade 5. For the different grades of injuries, improvement has been documented in 44% with complete healing in 34%, while 51% of injuries remained unchanged from the initial scan. Only 5% progressed to a higher-grade injury. Twelve patients developed strokes with an incidence of 9.4% in patients with a follow-up CTA.

CONCLUSIONS

This study can help increase the awareness of radiologists about the evolution patterns of different grades of BCVIs on follow-up CTA for severely injured posttraumatic patients.

Whole-body computed tomography in trauma patients: optimization of the patient scanning position significantly shortens examination time while maintaining diagnostic image quality

Background

The study was conducted to compare examination time and artifact vulnerability of whole-body computed tomographies (wbCTs) for trauma patients using conventional or optimized patient positioning.

Patients and methods

Examination time was measured in 100 patients scanned with conventional protocol (Group A: arms positioned alongside the body for head and neck imaging and over the head for trunk imaging) and 100 patients scanned with optimized protocol (Group B: arms flexed on a chest pillow without repositioning). Additionally, influence of two different scanning protocols on image quality in the most relevant body regions was assessed by two blinded readers.

Results

Total wbCT duration was about 35% or 3:46 min shorter in B than in A. Artifacts in aorta (27 vs 6%), liver (40 vs 8%) and spleen (27 vs 5%) occurred significantly more often in B than in A. No incident of non-diagnostic image quality was reported, and no significant differences for lungs and spine were found.

Conclusion

An optimized wbCT positioning protocol for trauma patients allows a significant reduction of examination time while still maintaining diagnostic image quality.

Diagnostic Imaging in Disasters: A Bibliometric Analysis

Objective

To investigate the role of diagnostic imaging in the clinical diagnosis, treatment, and follow-up management of patients in response to disasters.

Methods

A MEDLINE (OVID) search of original research articles identified 177 articles on this topic published since 2000. A bibliometric analysis was conducted on the top 100 articles ranked by average yearly citation.

Results

The most frequently studied disaster categories were disease outbreak (55 articles), armed conflict (23 articles), terrorist incident (10 articles), and earthquake (7 articles). The most studied disasters were the H1N1 influenza outbreak in 2009 (28 articles), Severe Acute Respiratory Syndrome outbreak in 2003 (24 articles), War in Afghanistan, 2001-2014 (8 articles), Iraq War, 2003-2011 (6 articles), and the Sichuan earthquake (China) in 2008 (6 articles). Among the first authors, 59 were primarily affiliated with Radiology. The United States of America produced the most articles (25 articles), followed by the People’s Republic of China (24 articles). Eighty-one studies were retrospective, with 19 studies being prospective. Computed tomography was the most investigated modality (52.8%), followed by conventional radiography (33.3%) and ultrasound (9.7%).

Conclusions

Our study identifies intellectual milestones in the utility of diagnostic imaging in response to various disasters, and could help guide future research in developing disaster management plans. (Disaster Med Public Health Preparedness. 2018;12:265–277)

Immediate total-body CT scanning versus conventional imaging and selective CT scanning in patients with severe trauma (REACT-2): a randomised controlled trial

BACKGROUND

Published work suggests a survival benefit for patients with trauma who undergo total-body CT scanning during the initial trauma assessment; however, level 1 evidence is absent. We aimed to assess the effect of total-body CT scanning compared with the standard work-up on in-hospital mortality in patients with trauma.

METHODS

We undertook an international, multicentre, randomised controlled trial at four hospitals in the Netherlands and one in Switzerland. Patients aged 18 years or older with trauma with compromised vital parameters, clinical suspicion of life-threatening injuries, or severe injury were randomly assigned (1:1) by ALEA randomisation to immediate total-body CT scanning or to a standard work-up with conventional imaging supplemented with selective CT scanning. Neither doctors nor patients were masked to treatment allocation. The primary endpoint was in-hospital mortality, analysed in the intention-to-treat population and in subgroups of patients with polytrauma and those with traumatic brain injury. The χ(2) test was used to assess differences in mortality. This trial is registered with ClinicalTrials.gov, number NCT01523626.

FINDINGS

Between April 22, 2011, and Jan 1, 2014, 5475 patients were assessed for eligibility, 1403 of whom were randomly assigned: 702 to immediate total-body CT scanning and 701 to the standard work-up. 541 patients in the immediate total-body CT scanning group and 542 in the standard work-up group were included in the primary analysis. In-hospital mortality did not differ between groups (total-body CT 86 [16%] of 541 vs standard work-up 85 [16%] of 542; p=0.92). In-hospital mortality also did not differ between groups in subgroup analyses in patients with polytrauma (total-body CT 81 [22%] of 362 vs standard work-up 82 [25%] of 331; p=0.46) and traumatic brain injury (68 [38%] of 178 vs 66 [44%] of 151; p=0.31). Three serious adverse events were reported in patients in the total-body CT group (1%), one in the standard work-up group (<1%), and one in a patient who was excluded after random allocation. All five patients died.

INTERPRETATION

Diagnosing patients with an immediate total-body CT scan does not reduce in-hospital mortality compared with the standard radiological work-up. Because of the increased radiation dose, future research should focus on the selection of patients who will benefit from immediate total-body CT.

FUNDING

ZonMw, the Netherlands Organisation for Health Research and Development.

Indications for total-body computed tomography in blunt trauma patients: a systematic review

PURPOSE

Total-body CT scanning (TBCT) could improve the initial in-hospital evaluation of severe trauma patients. Indications for TBCT, however, differ between trauma centers, so more insight in how to select patients that could benefit from TBCT is required. The aim of this review was to give an overview of currently used indications for total-body CT in trauma patients and to describe mortality and Injury Severity Scores of patient groups selected for TBCT.

METHODS

A systematic review was performed by searching MEDLINE and Embase databases. Studies evaluating or describing criteria for selection of patients with potentially severe injuries for TBCT during initial trauma care were included. Also, studies comparing total-body CT during the initial assessment of injured patients with conventional imaging and selective CT in specific patient groups were included.

RESULTS

Thirty eligible studies were identified. Three studies evaluated indications for TBCT in trauma with divergent methods. Combinations of compromised vital parameters, severe trauma mechanisms and clinical suspicion on severe injuries are often used indications; however, clinical judgement is used as well. Studies describing TBCT indications selected patients in different ways and were difficult to compare regarding mortality and injury severity.

CONCLUSIONS

Indications for TBCT in trauma show a wide variety in structure and cut-off values for vital parameters and trauma mechanism dimensions. Consensus on indications for TBCT in trauma is lacking.

Improving Outcomes in the Patient with Polytrauma: A Review of the Role of Whole-Body Computed Tomography

Whole-body computed tomography (WBCT) is used for the workup of the patient with blunt polytrauma. WBCT is associated with improved patient survival and reduces the emergency department length of stay. However, randomized studies are needed to determine whether early WBCT improves survival, to clarify which patients benefit the most, and to model the costs of this technique compared with traditional workup. Advancements in modern multidetector computed tomography technology and an improved understanding of optimal protocols have enabled one to scan the entire body and achieve adequate image quality for a comprehensive trauma assessment in a short period.

The quality movement or making radiology fun again

Quality can be seen as the link between what we do as radiologists and patient health. The radiology quality movement represents an opportunity for radiologists to have more direct influence on patient health, including the quality domains of safety, effectiveness, patient centeredness, timeliness, efficiency, and equitability. Focusing on quality allows emergency radiologists to extend outside of the confines of the reading room, thereby enhancing a rewarding and clinically relevant practice.