Trauma whole-body MDCT: an assessment of image quality in conventional dual-phase and modified biphasic injection

Grading Abdominal Trauma: Changes in and Implications of the Revised 2018 AAST-OIS for the Spleen, Liver, and Kidney

According to the Centers for Disease Control and Prevention, trauma is the leading cause of fatal injuries for Americans aged 1-44 years old and the fourth leading overall cause of death. Accurate and early diagnosis, including grading of solid organ injuries after blunt abdominal trauma (BAT), is crucial to guide management and improve outcomes. The American Association for the Surgery of Trauma (AAST) Organ Injury Scale (OIS) is the most widely accepted BAT scoring system at CT both within the United States and internationally, and its uses include stratification of injury severity, thereby guiding management, and facilitation of clinical research, billing, and coding. Furthermore, this system also plays a role in the credentialing process for trauma centers in the United States. The newly revised 2018 OIS provides criteria for grading solid organ damage into three groups: imaging, operation, and pathology. The final grade is based on the highest of the three criteria. If multiple lower-grade (I or II) injuries are present in a single organ, one grade is advanced to grade III. The most substantial change in the revised 2018 AAST-OIS is incorporation of multidetector CT findings of vascular injury, including pseudoaneurysm and arteriovenous fistula. The authors outline the main revised aspects of grading organ injury using the AAST-OIS for the spleen, liver, and kidney after BAT, particularly the role of multidetector CT and alternative imaging in organ injury detection, the importance of vascular injuries in grade change, and the impact of these changes on patient management and in prediction of operative treatment success and in-hospital mortality. ©RSNA, 2023 Supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available through the Online Learning Center.

The value of performing cerebrovascular CT angiography in major trauma patients: a 5-year retrospective review

AIM

To assess whether routine cerebrovascular imaging is required in all major trauma (MT) patients.

MATERIALS AND METHODS

All MT patients with cerebrovascular imaging between January 2015 and December 2020 were included in the study. Data were collated regarding the type of indication for computed tomography (CT) angiography imaging, time interval from the initial trauma, relevant trauma diagnoses on initial trauma imaging, and CT angiography. Findings, such as aneurysms, vascular malformations, luminal thrombus, venous sinus thrombosis, or vascular injury, were collated. Subsequent treatment with anti-coagulants/anti-platelets or surgical/radiological intervention was noted. Follow-up imaging was assessed for residual injury or complications.

RESULTS

Two hundred and fifty of the 6,251 MT patients underwent dedicated cerebrovascular imaging and were included in the study. Of these 41 (16.4%) had cervical artery or venous sinus injury. Further positive vascular findings were identified in 25/250 patients who presented with an incidental stroke or a vascular abnormality and were mislabelled as MT patients at presentation. One patient with a carotid injury subsequently died following a large infarction. Another patient with vertebral artery injury suffered a non-lethal stroke. No patients underwent surgery or intervention.

CONCLUSION

The present study showed that the overall incidence of detected blunt cerebrovascular injuries was very low (0.6%) and even lower for symptomatic vascular injury (0.03%). Routine cerebrovascular imaging is not recommended in all MT trauma patients, but instead, a continued case-by-case basis should be considered.

How to deliver an effective primary survey report for the trauma CT: A radiological and surgical perspective

Whole body contrast-enhanced multidetector CT (WB-CE MDCT) is integral to the assessment of the severely injured patient with stable haemodynamic parameters or in those who respond to resuscitation with blood products. WB-CE MDCT is able to identify the number and severity of injuries sustained by the patient and enable time critical intervention.

In this narrative review article we discuss how communication within the trauma team, including the radiologists and appropriate clinicians is crucial in optimizing the effectiveness of WB-CE MDCT. We review the time critical imaging findings and their clinical relevance, which should be included in a succinct CT primary survey report.

We also discuss the process through which the effectiveness of the trauma report may be maximised and how non technical factors including teamwork may be optimised to facilitate decision making in this high pressure environment.

Yield of whole-body computed tomography at a low-volume emergency department: A 5-year experience

Objectives:

To share our experience with immediate whole-body computed tomography (WBCT) imaging for trauma patients and to determine its association with surgical intervention and hospital admission.

Methods:

This retrospective observational study included 208 trauma patients who presented to the emergency department and underwent WBCT at the King Abdulaziz University Hospital, Jeddah, Saudi Arabia between January 2014 and November 2018. We excluded pregnant patients and those who went into traumatic cardiac arrest or died before imaging.

Results:

Of all included patients, 48.6% were adults and 72.1% had positive findings; of these, 36.7% of patients were admitted for observation and 27.3% underwent operative interventions.

Conclusion:

Whole-body computed tomography is a useful tool to detect significant traumatic injuries in patients presenting to the emergency department. Moreover, it may assist physicians in determining the disposition of these patients. A clear set of criteria should be established to determine which trauma patients require WBCT imaging during initial resuscitation.

Penetrating gluteal injuries in North West London: a retrospective cohort study and initial management guideline

Background

Penetrating gluteal injuries (PGIs) are an increasingly common presentation to major trauma centers (MTCs) in the UK and especially in London. PGIs can be associated with mortality and significant morbidity. There is a paucity of consistent guidance on how best to investigate and manage these patients.

Methods

A retrospective cohort study was performed by interrogating prospectively collected patient records for PGI presenting to a level 1 MTC in London between 2017 and 2019.

Results

There were 125 presentations with PGI, accounting for 6.86% of all penetrating injuries. Of these, 95.2% (119) were male, with a median age of 21 (IQR 18–29), and 20.80% (26) were under 18. Compared with the 3 years prior to this study, the number of PGI increased by 87%. The absolute risk (AR) of injury to a significant structure was 27.20%; the most frequently injured structure was a blood vessel (17.60%), followed by the rectum (4.80%) and the urethra (1.60%). The AR by anatomic quadrant of injury was highest in the lower inner quadrant (56%) and lowest in the upper outer quadrant (14%). CT scanning had an overall sensitivity of 50% and specificity of 92.38% in identifying rectal injury.

Discussion

The anatomic quadrant of injury can be helpful in stratifying risk of rectal and urethral injuries when assessing a patient in the emergency department. Given the low sensitivity in identifying rectal injury on initial CT, this data supports assesing any patients considered at high risk of rectal injury with an examination under general anesthetic with or without rigid sigmoidoscopy. The pathway has created a clear tool that optimizes investigation and treatment, minimizing the likelihood of missed injury or unnecessary use of resources. It therefore represents a potential pathway other centers receiving a similar trauma burden could consider adopting.

Level of evidence

2b.

Whole-body computed tomography is safe, effective and efficient in the severely injured hemodynamically unstable trauma patient

Trauma is a complex pathology that requires an experienced multidisciplinary team with an inherent quick decision-making capacity, given that a few minutes could represent a matter of life or death. These management decisions not only need to be quick but also accurate to be able to prioritize and to efficiently control the injuries that may be causing impending hemodynamic collapse. In essence, this is the cornerstone of the concept of damage control trauma care. With current technological advances, physicians have at their disposition multiple diagnostic imaging tools that can aid in this prompt decision-making algorithm. This manuscript aims to perform a literature review on this subject and to share the experience on the use of whole body computed tomography as a potentially safe, effective and efficient diagnostic tool in cases of severely injured trauma patients regardless of their hemodynamic status. Our general recommendation is that, when feasible, perform a whole body computed tomography without interrupting ongoing hemostatic resuscitation in cases of severely injured trauma patients with or without signs of hemodynamic instability. The use of this technology will aid in the decision-making of the best surgical approach for these patients without incurring any delay in definitive management and/or increasing significantly their radiation exposure.

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.

Implementation of a new Single-Pass Whole-Body Computed Tomography Protocol: Is it safe, effective and efficient in patients with severe trauma?

Purpose:

The objective of this study was to evaluate the implementation of a new single-pass whole-body computed tomography Protocol in the management of patients with severe trauma.

Methods:

This was a descriptive evaluation of polytrauma patients who underwent whole-body computed tomography. Patients were divided into three groups: 1. Blunt trauma hemodynamically stable 2. Blunt trauma hemodynamically unstable and 3. Penetrating trauma. Demographics, whole-body computed tomography parameters and outcome variables were evaluated.

Results:

Were included 263 patients. Median injury severity score was 22 (IQR: 16-22). Time between arrival to the emergency department and completing the whole-body computed tomography was under 30 minutes in most patients [Group 1: 28 minutes (IQR: 14-55), Group 2: 29 minutes (IQR: 16-57), and Group 3: 31 minutes (IQR: 13-50; p= 0.96)]. 172 patients (65.4%) underwent non-operative management. The calculated and the real survival rates did not vary among the groups either [Group 1: TRISS 86.4% vs. real survival rate 85% (p= 0.69); Group 2: TRISS 69% vs. real survival rate 74% (p= 0.25); Group 3: TRISS 93% vs. real survival rate 87% (p= 0.07)].

Conclusion:

This new single-pass whole-body computed tomography protocol was safe, effective and efficient to decide whether the patient with severe trauma requires a surgical intervention independently of the mechanism of injury or the hemodynamic stability of the patient. Its use could also potentially reduce the rate of unnecessary surgical interventions of patients with severe trauma including those with penetrating trauma.

Uso de la tomografía corporal total en pacientes con trauma grave

Introducción. La tomografía corporal (TC) total en la evaluación de pacientes con trauma grave, puede ser una herramienta eficaz y segura para decidir entre un tratamiento quirúrgico y uno no quirúrgico, pero aún no son claras las implicaciones diagnósticas y los riesgos asociados con esta técnica. Métodos. Se incluyeron pacientes mayores de 15 años con trauma grave que fueron sometidos a TC total. Se evaluaron la seguridad, la efectividad y la eficiencia por medio de los parámetros de incidencia de nefropatía inducida por los medios de contraste, dosis total de radiación por paciente, proporción de casos en los que la TC total cambió el manejo, y el retraso en el diagnóstico. Resultados. Se incluyeron 263 pacientes, 83 % sufrieron trauma cerrado y 17 % sufrieron trauma penetrante. La gravedad de la lesión fue mayor en estos últimos y, sin embargo, el trauma cerrado con inestabilidad hemodinámica se presentó con mayores grados de choque. El 65 % de los pacientes recibió tratamiento selectivo no operatorio. Entre los subgrupos, no hubo diferencias significativas en el tiempo entre el ingreso a la sala de urgencias y la toma de la TC total (p=0,96) y, en la mayoría de los casos, el tiempo entre la práctica de la TC total y el diagnóstico de presencia o ausencia de heridas fue menor de 25 minutos. La mediana de radiación total estuvo por debajo de 20 mSv en todos los grupos. No hubo diferencias significativas en la mortalidad (p=0,17). Conclusión. La TC total es una herramienta segura y eficiente para decidir entre un tratamiento quirúrgico y uno no quirúrgico en los casos de trauma grave, independientemente del mecanismo de la lesión o la estabilidad hemodinámica al ingreso.

Dual-Energy CT: A Paradigm Shift in Acute Traumatic Abdomen

Abdominal trauma, one of the leading causes of death under the age of 45, can be broadly classified into blunt and penetrating trauma, based on the mechanism of injury. Blunt abdominal trauma usually results from motor vehicle collisions, fall from heights, assaults, and sports and is more common than penetrating abdominal trauma, which is usually seen in firearm injuries and stab wounds. In both blunt and penetrating abdominal trauma, an optimized imaging approach is mandatory to exclude life-threatening injuries. Easy availability of the portable ultrasound in the emergency department and trauma bay makes it one of the most commonly used screening imaging modalities in the abdominal trauma, especially to exclude hemoperitoneum. Evaluation of the visceral and vascular injuries in a hemodynamically stable patient, however, warrants intravenous contrast-enhanced multidetector computed tomography scan. Dual-energy computed tomography with its postprocessing applications such as iodine selective imaging and virtual monoenergetic imaging can reliably depict the conspicuity of traumatic solid and hollow visceral and vascular injuries.

Whole-Body Computed Tomography Using Low-Dose Biphasic Injection Protocol With Adaptive Statistical Iterative Reconstruction V: Assessment of Dose Reduction and Image Quality in Trauma Patients

AIM

This study aimed to evaluate potential dose savings on a revised protocol for whole-body computed tomography and image quality after implementing Adaptive Statistical Iterative Reconstruction V (ASiR-V) algorism for trauma patients and compare it with routine protocol.

MATERIALS AND METHODS

One hundred trauma patients were classified into 2 groups using 2 different scanning protocols. Group A (n = 50; age, 32.48 ± 8.09 years) underwent routine 3-phase protocol. Group B (n = 50; age, 35.94 ± 13.57 years) underwent biphasic injection protocol including unenhanced scan for the brain and cervical spines, followed by a 1-step acquisition of the thorax, abdomen, and pelvis. The ASiR-V level was kept at 50% for all examinations, and then studies were reconstructed at 0% ASiR-V level. Radiation dose, total acquisition time, and image count were compared between groups (A and B). Two radiologists independently graded image quality and artifacts between both groups and 2 ASiR-V levels (0 and 50%).

RESULTS

The mean (±SD) dose-length product value for postcontrast scans in group A was 1602.3 ± 271.8 mGy · cm and higher when compared with group B (P < 0.001), which was 951.1 ± 359.6 mGy · cm. Biphasic injection protocol gave a dose reduction of 40.4% and reduced the total acquisition time by 11.4% and image count by 37.6%. There was no statistically significant difference between the image quality scores for both groups; however, group A scored higher grades (4.62 ± 0.56 and 4.56 ± 0.67). Similarly, the image quality scores for both ASiR-V levels in both groups were not significantly different.

CONCLUSIONS

Biphasic computed tomography protocol reduced radiation dose with maintenance of diagnostic accuracy and image quality after implementing ASiR-V algorism.

CT of blunt splenic injuries: what the trauma team wants to know from the radiologist

Splenic injury is commonly encountered in severe blunt abdominal trauma. Technological improvements and the increasing availability of both diagnostic computed tomography (CT) and therapeutic splenic artery embolisation (SAE) are key factors in defining the high success rate of modern-day non-operative management (NOM) for blunt splenic injuries (BSIs). The Association for Surgery for Trauma (AAST) Organ Injury Scale (OIS) is commonly used by both radiologists and clinicians to stratify injury severity, traditionally based on the degree of parenchymal disruption seen on CT, and guide management. Its recent 2018 update takes splenic vascular injuries (i.e., active bleed, pseudoaneurysm, and traumatic arteriovenous fistulae) into consideration, the presence of which will indicate at least a grade IV (i.e., high-grade) injury. This is a reflection of the paradigm shift towards spleen conservation with regular use of SAE as the current standard of treatment. Prompted by the latest AAST OIS revision, which represents a more complete and current grading system, we present the spectrum of pertinent CT findings that the diagnostic radiologist should accurately identify and convey to the multidisciplinary trauma team (including the interventional radiologist). This review divides imaging findings based on the AAST OIS definitions and categorises them into (1) parenchymal and (2) vascular injuries. Features that may help in the detection of subtle BSIs are also described. Lastly, it touches on the key changes made to the new AAST OIS, substantiated by case illustrations.

Trans-arterial embolisation (TAE) in haemorrhagic pelvic injury: review of management and mid-term outcome of a major trauma centre

BACKGROUND

Management of pelvic fracture associated haemorrhage is often complex with high morbidity and mortality rates. Different treatment options are used to control bleeding with an on-going discussion in the trauma community regarding the best management algorithm.

MAIN BODY

Recent studies have shown trans-arterial embolisation (TAE) to be a safe and effective technique to control pelvic fracture associated haemorrhage. Computed tomography (CT) evidence of active bleeding, haemodynamic instability, and pelvic fracture patterns are amongst important indicators for TAE.

CONCLUSION

Herein, we aim to provide a comprehensive literature review of the effectiveness of TAE in controlling haemorrhage secondary to pelvic fracture according to the indications, technique and embolic agents, and outcomes, whilst incorporating our Level 1 major trauma centre's (MTC) results between 2014-2017.

Whole-body computed tomography in severely injured patients

PURPOSE OF REVIEW

To provide an update on the relevant and recent studies on whole-body computed tomography (WBCT) imaging of severely injured patients.

RECENT FINDINGS

The advantages of WBCT in time saving, diagnostic accuracy and even in survival have been proven in numerous studies. WBCT can also be beneficial in haemodynamically unstable major trauma patients. The CT scanner should be located close to the emergency department or even in the trauma room. The issue of radiation is still quite important, however, iterative as well as split-bolus protocols can nowadays reduce radiation significantly. The question: which trauma patient should receive WBCT and which not is not yet solved sufficiently. Postmortem WBCT has a promising potential to promptly define the definitive cause of death of trauma victims comparably to traditional autopsy.

SUMMARY

On account of the recent advances, whole-body CT has become a crucial part of the initial in-hospital assessment of severely injured patients. It is recommended as the standard radiological tool for the emergency diagnostic work-up in major trauma patients.

Triple-split-bolus versus single-bolus CT in abdominal trauma patients: a comparative study

Background Split-bolus computed tomography (CT) is a recent development in trauma imaging. Instead of multiple scans in different contrast phases after a single contrast bolus, split-bolus protocols consist of one single scan of the thorax and abdomen after two or three contrast injections at different points of time. Purpose To evaluate and compare image quality and injury findings of a new triple-split-bolus CT (TS-CT) protocol of thorax and abdomen with those of a portal venous phase CT (PV-CT) in the same patient group. Material and Methods Trauma patients in 2009-2012 who underwent both the TS-CT initially and a PV-CT during the next six weeks were included. The TS-CT examination was performed as one CT run after application of three contrast boluses (total 175 mL) to enhance renal pelvis and urinary tract, the abdominal organs, and the large arterial vessels. The PV-CT had a fixed delay of 85 s. We measured attenuation in Hounsfield units (HU), evaluated possible organ injury and assessed image quality on a 5-point scale. Results Thirty-five patients were included. Attenuation measurements of major abdominal vessels, organs, and renal pelvis were significantly higher with the TS-CT protocol. Performance in organ injury diagnosis and image quality was equal in both protocols. Conclusion The overall performance of the TS-CT protocol is similar to the standard PV-CT. Excellent visualization of the arterial tree and the collecting system may eliminate the need for separate scans.

Trauma in the elderly patient

Major Trauma Centres and Emergency Departments are treating an increasing number of elderly trauma patients in the UK. Elderly patients, defined as those over the age of 65 years, are more susceptible to injury from lesser mechanisms of trauma than younger adults. The number of elderly trauma cases is rising yearly, accounting for >25% of all major trauma nationally. The elderly have different physiological reserves and a different response to trauma due to premorbid frailty, co-existing conditions and prescribed medication. These factors need to be appreciated in trauma triaging, radiological assessment and clinical management. A lower threshold for trauma-call activation is recommended, including a lower threshold for advanced imaging. We will review general principles of trauma in the elderly, outline injury patterns in this age group and illustrate the radiological features per anatomical site, from head to pelvis and the extremities. We advocate using contrast-enhanced computed tomography as the primary diagnostic imaging modality as concern about intravenous contrast agent-induced nephropathy is relatively minor. Prompt investigation and diagnosis leads to timely appropriate treatment, therefore the radiologist can discerningly improve morbidity and mortality in this vulnerable group.

Pearls and pitfalls in imaging of blunt traumatic thoracic aortic injury: a pictorial review

Blunt thoracic aortic injury (TAI) occurs most frequently as a sequelae of high impact deceleration such as high-velocity road traffic accidents and falls from height. The burden of mortality and morbidity is high, however advances in pre-hospital care, diagnostic imaging and endovascular therapies have improved outcomes in this group of patients. Emergent treatment depends on accurate, early diagnosis by the radiologist. It is therefore of paramount importance that radiologists are familiar with both the direct (intimal flap, pseudoaneurysm, aortic contour irregularity and contrast extravasation) and indirect (periaortic haematoma) imaging findings of TAI. Furthermore, it is critical that technical (breathing artefact and cardiac motion artefact) as well as anatomical (ductus diverticulum, aortic spindle and mediastinal structures which imitate periaortic haematoma) pitfalls are recognised to avoid misdiagnosis. This pictorial review will help the diagnostic radiologist to recognise the patterns of injury and imaging features associated with TAI, as well as highlighting potential mimics when interrogating CTangiography (CTA) in major trauma.

Evaluation of a single-pass with biphasic intravenous contrast medium injection CT protocol for the assessment of complications post-simultaneous pancreas-kidney transplant

AIM

To evaluate the use of a single-pass with biphasic intravenous contrast medium injection computed tomography (CT) protocol to provide diagnostic quality CT studies for the assessment of complications post-simultaneous pancreas-kidney transplant (SPK).

MATERIALS AND METHODS

This was an audit of practice and the need for informed consent was waived. The protocol was used in consecutive patients undergoing CT to exclude intra-abdominal sepsis post-SPK between June and December 2015. Single CT acquisition of the abdomen and pelvis was initiated 70 seconds after the start of biphasic contrast medium injection (66 ml at 1.2 ml/s, followed by 34 ml at 2.4 ml/s, 370 mg iodine/ml). The named transplant pancreas vessels were identified and the attenuation values of the blood within were measured. Diagnostic quality was confirmed if values were >211 HU and >80 HU in the arteries and veins, respectively.

RESULTS

Thirteen CT studies were performed in 10 patients. CT studies were excluded due to complete pancreatic necrosis, and transplant superior mesenteric artery (SMA) thrombus with pancreatic head ischaemia causing effacement of the transplant superior mesenteric vein (SMV). Diagnostic quality of the analysed CT studies were confirmed with mean attenuation value of blood >211 HU in the transplant pancreatic arteries (SMA=259.0±51.4 HU, splenic artery=245.3±37.5 HU), and >80 HU in the pancreatic veins (SMV=195.4±36.2 HU, splenic vein=185.1±54.2 HU).

CONCLUSION

Diagnostic quality CT studies were obtained using the single-pass CT protocol. Radiation exposure to patients may be reduced with this protocol, while permitting simultaneous assessment of parenchymal and vascular complications post-SPK.

Investigation of an appropriate contrast-enhanced CT protocol for young patients following the Fontan operation

PURPOSE

Children with congenital heart diseases (CHDs) may need to be followed up with contrast-enhanced CT following the Fontan operation because complications such as the occlusion of conduits may occur. The purpose of the present study was to develop an adequate contrast-enhanced CT protocol for children with CHD following the Fontan operation.

MATERIALS AND METHODS

Between July 2012 and July 2017, 29 CT examinations for 26 patients aged 2-11 years (median 5 years) with CHD following the Fontan operation were performed using dual-source CT. A non-ionized contrast medium was injected through the dorsum manus vein. Scanning began 60 or 70 s after the start of the injection. The delayed phase was randomly selected to be 60 s in 14 cases and 70 s in 15 cases. We evaluated the enhancement of conduits following the Fontan operation at delayed phases.

RESULTS

The CT numbers of conduits at 60 and 70 s were 185 ± 46 and 185 ± 31 HU, respectively (P = 0.97).

CONCLUSION

In contrast-enhanced CT for children after the Fontan operation, both of the delayed phases (60 and 70 s) appeared to be adequate for evaluating intraconduit patency.