A clinically relevant liver injury grading system by CT, preliminary report

Predictors of need for endovascular intervention in hepatic trauma

PURPOSE

Non-operative management of hepatic trauma with adjunctive hepatic arterial embolization (HAE) is widely accepted. Despite careful patient selection utilizing CTA, a substantial proportion of angiograms are negative for arterial injury and no HAE is performed. This study aims to determine which CT imaging findings and clinical factors are associated with the presence of active extravasation on subsequent angiography in patients with hepatic trauma.

MATERIALS AND METHODS

The charts of 243 adults who presented with abdominal trauma and underwent abdominal CTA followed by conventional angiography were retrospectively reviewed. Of these patients, 49 had hepatic injuries on CTA. Hepatic injuries were graded using the American association for the surgery of trauma (AAST) CT classification, and CT images were assessed for active contrast extravasation, arterial pseudoaneurysm, sentinel clot, hemoperitoneum, laceration in-volving more than 2 segments, and laceration involving specific anatomic landmarks (porta hepatis, hepatic veins, and gallbladder fossa). Medical records were reviewed for pre- and post-angiography blood pressures, hemoglobin levels, and transfusion requirements. Angiographic images and reports were reviewed for hepatic arterial injury and performance of HAE.

RESULTS

In multivariate analysis, AAST hepatic injury grade was significantly associated with increased odds of HAE (Odds ratio: 2.5, 95% CI 1.1, 7.1, p = 0.049). Univariate analyses demonstrated no significant association between CT liver injury grade, CT characteristics of liver injury, or pre-angiographic clinical data with need for HAE.

CONCLUSION

In patients with hepatic trauma, prediction of need for HAE based on CT findings alone is challenging; such patients require consideration of both clinical factors and imaging findings.

Diagnostic accuracy of postmortem computed tomography for bleeding source determination in cases with hemoperitoneum

Aim

The aim of this retrospective study was to determine the accuracy of postmortem computed tomography and different radiological signs for the determination of the bleeding source in cases with hemoperitoneum confirmed at autopsy.

Methods

Postmortem computed tomography data of consecutive cases with hemoperitoneum confirmed at autopsy were reviewed by two raters, blinded to the autopsy findings. The determination of possible bleeding sources was based on the presence of the sentinel clot sign, blood or sedimented blood surrounding an organ, intraparenchymal abnormal gas distribution, and parenchymal disruption. The bleeding source and the cause of hemoperitoneum (traumatic, surgical, natural, or resuscitation) as reported in the autopsy report were noted. The survival intervals of the deceased were calculated when information about the time of an incident related to death was available in the autopsy reports.

Results

Eighty-five cases were included in the study. Postmortem computed tomography showed 79% sensitivity and 92.1% specificity for the detection of the bleeding source. The sentinel clot sign was associated with surgical or natural causes of hemoperitoneum and longer survival intervals. Sedimented blood around the bleeding source was associated with resuscitation. Abnormal gas distribution within organs and combination of multiple radiological signs provided higher sensitivity.

Conclusion

Postmortem computed tomography provides moderate sensitivity and high specificity for determining the bleeding source in cases with hemoperitoneum. Different PMCT signs are associated with different causes of hemoperitoneum and survival intervals.

Organ laceration grading adherence by radiologists

American Association for the Surgery of Trauma (AAST) abdominopelvic organ laceration grading is used to determine which patients can be managed non-operatively. We assess a change in the use of AAST grading system by radiologists at a single, large, academic institution before and after a one-time departmental intervention and reviewed non-graded reports evaluating if grading could be inferred. After IRB approval, a keyword search for "laceration" identified traumatic abdominopelvic CT reports in a 2-year period before and after the one-time intervention. Reports were reviewed to determine if an organ laceration was seen, if it was graded by AAST criteria, and if grading could be inferred for non-graded reports. T test was performed to assess statistical significance. Before the intervention, 348 reports contained the keyword "laceration," 81 with lacerations, 31 graded (38 %). After the intervention, 302 reports were found, 79 with lacerations, 59 graded (75 %). The increase was statistically significant (p < 0.0001). A decreasing trend in grading was seen over time following the intervention. Two out of 50 (4 %) pre-intervention and four out of 20 (20 %) post-intervention reports gave enough detailed descriptions for the grading to be inferred when it was not explicitly stated. Non-graded reports did not describe laceration parenchymal depth and subcapsular hematoma surface area percentage; however, the presence/absence of active extravasation, omitted in the 20-year-old AAST grading scheme, was described in every report. One-time departmental intervention yielded a significant increase in adherence to AAST laceration grading. Lack of perfect compliance, which diminished over time, suggests a need for further reinforcement.

Non-operative management of liver trauma

The liver is one of the commonest intra-abdominal organs injured worldwide in blunt and penetrating trauma and its management has evolved significantly in the last 30 years. Mandatory laparotomy has been replaced by an acceptance that for most blunt hepatic trauma, a selective non-operative approach is safe and effective with a failure rate ie the need to proceed to delayed laparotomy of approximately 10%. There is a markedly lower rate of complications in those that are managed non-operatively. Adjuncts to this conservative regimen such as angioembolisation and delayed laparoscopy to treat biliary peritonitis increase the chances of avoiding laparotomy. This belief in non-operative management has also been transferred to some degree to penetrating liver trauma, where there is a gradual accumulation of evidence to support this non-operative approach in a carefully selected group of patients. This article examines the evidence supporting the selective non-operative management of both blunt and penetrating liver trauma and describes the outcomes and complications.

Blunt polytrauma: evaluation with 64-section whole-body CT angiography

Blunt polytrauma remains a leading cause of death and disability worldwide. With the major advances in computed tomography (CT) technology over the past decade, whole-body CT is increasingly recognized as the emerging standard for providing rapid and accurate diagnoses within the narrow therapeutic window afforded to trauma victims with multiple severe injuries. With a single continuous acquisition, whole-body CT angiography is able to demonstrate all potentially injured organs, as well as vascular and bone structures, from the circle of Willis to the symphysis pubis. As its use becomes more widespread, the large volume of information inherent to whole-body CT poses new challenges to radiologists in providing efficient and timely interpretation. An awareness of trauma scoring systems and injury mechanisms is essential to maintain an appropriate level of suspicion in the search for multiple injuries, and the use of multiplanar reformation and three-dimensional postprocessing techniques is important to maximize efficiency in the search. Knowledge of the key injuries that require urgent surgical or percutaneous intervention, including major vascular injuries and active hemorrhage, diaphragmatic rupture, unstable spinal fractures, pancreatic injuries with ductal involvement, and injuries to the mesentery and hollow viscera, is also necessary.

Solid Organ Injury Grading in Trauma: Accuracy of Grading by Surgical Residents

The American Association for the Surgery of Trauma developed an Organ Injury Scale for management of patients with splenic, kidney, or liver injuries. Despite widespread use of the guidelines, the person who determines the injury grade varies among institutions. Our purpose was to determine the accuracy and interobserver agreement between surgical residents and a radiologist in grading solid organ injuries. We retrospectively reviewed patients with solid organ injuries from January 2009 to May 2010 and compared the grade of solid organ injuries by a single resident with grades by a single blinded radiologist using a paired t test, analysis of variance, or Kruskal-Wallis. Computed tomography scans of 58 patients with splenic injuries, 43 with liver injuries, and 16 with kidney injuries were reviewed. Average grades for splenic injuries were 2.5 and 2.4 (radiologist/resident); liver injuries, 2.6 and 2.1; and kidney injuries, 2.7 and 2.8. There were no significant differences in grading by the radiologist and resident for splenic and kidney injuries; however, equal values were only achieved in 43 and 38 per cent, respectively. There was a significant difference (average rating difference 0.54, P = 0.0002) in grading between the radiologist and resident for liver injuries with only 35 per cent having equal values and the radiologist grading on average 0.5 points higher than the resident. No demographic, injury, or outcome variables were significantly associated with interobserver variability ( P > 0.05). Despite a significant difference for liver injury grading, interobserver agreement between residents and a single radiologist was low. Clinical implications and the impact on outcomes related to interobserver variations require further study.

Low-dose MDCT findings of blunt hepatobiliary trauma

This pictorial essay shows low-dose multi-detector computed tomography (MDCT) findings of blunt hepatobiliary trauma, and describes the indications and protocol for MDCT. Given the universal usage of MDCT in assessing the liver in blunt abdominal trauma, reduction of patient dose is essential. The new l0se MDCT protocol presented here can achieve up to 50% dose reduction while maintaining diagnostic image quality and thus facilitate dose sensitive patient management. Our institution's blunt hepatobiliary MDCT imaging algorithm can help determine which patients require operative therapy. Injury to the liver is graded on various schemes, one being the Organ Injury Scale devised by the American Association for the Surgery of Trauma classification based on the extension of the lesion and bleeding.

[Hepatic trauma. Interventional and conservative therapy]

The non-operative management of hemodynamically stable patients with liver trauma has become the standard of care. Non-operative treatment has a success rate of >80%. In the majority of cases of hemodynamic instability or high grade liver injuries, however, a surgical approach is necessary. As for conservative treatment of liver trauma the surveillance of patients in the ICU is of utmost importance. Repeat CT scans are only necessary in patients with high grade injuries or in case of complications. Interventional procedures, such as the endoscopic retrograde cholangiopancreatography in cases of biliary complications or angiography for vascular complications, are increasingly being used in order to avoid surgery. The success rates of non-operative strategies have been improving continuously over the last decades.

Computed Tomography Grading Systems Poorly Predict the Need for Intervention after Spleen and Liver Injuries

Computed tomography (CT) grading systems are often used clinically to forecast the need for interventions after abdominal trauma with solid organ injuries. We compared spleen and liver CT grading methods to determine their utility in predicting the need for operative intervention or angiographic embolization. Abdominal CT scans of 300 patients with spleen injuries, liver injuries, or both were evaluated by five trauma faculty members blinded to clinical outcomes. Studies were graded by American Association for the Surgery of Trauma criteria, a novel splenic injury CT grading system, and a novel liver injury grading system. The sensitivity and specificity of each methodology in predicting the need for intervention were calculated. The kappa statistic was used to determine interrater variability. Twenty-one per cent (39/189) of patients with splenic injuries visible on CT scans required interventions, whereas 14 per cent (21/154) of patients with liver injuries visible on CT required interventions. The overall sensitivity of all grading systems in predicting the need for surgery or angioembolization of the spleen or liver was poor; the specificity seemed to be fairly good. When evaluators were compared, the strength of agreement for the various scoring systems was only moderate. Anatomic CT grading systems are ineffective screening tools for excluding the need for operation or embolization after splenic or hepatic trauma. Although insensitive, CT is a good predictor (highly specific) of the need for intervention if certain definitive abnormalities are identified. Considerable inconsistency exists in interpretation of abdominal CT scans after trauma, even among experienced clinicians.

Vascular emergencies in liver trauma

The use of CT in the diagnosis and management of liver trauma is responsible for the shift from routine surgical versus non-surgical treatment in the management of traumatic liver injuries, even when they are of high grade. The main cause of complication and of death in liver trauma is related to vascular injury. The goal of this review focussed on the vascular complications of liver trauma is to describe the elementary lesions shown by CT in liver trauma including laceration, parenchymal hematoma and contusions, partial devascularisation, subcapsular hematomas, hemoperitoneum, active bleeding, pseudoaneurysm of the hepatic artery, bile leak, and periportal oedema, to illustrate the possible pitfalls in CT diagnosis of liver trauma and to underline the key-points which may absolutely be present in a CT report of liver trauma. Then we will remind the grading system based on the CT features and we will analyze the interest and limitations of such grading systems. Last we will discuss the diagnostic strategy at the early phase in patients with suspected liver trauma according to their clinical conditions and underline the conditions of arterial embolization, and then we will discuss the diagnosis strategy at the delayed phase according to the suspected complications.

Blunt abdominal trauma: current imaging techniques and CT findings in patients with solid organ, bowel, and mesenteric injury

Imaging plays a critical role in the evaluation of patients with blunt abdominal trauma. In most institutions, computed tomography (CT) is the modality of choice when evaluating such patients. The purpose of this review is to highlight current techniques in trauma imaging and to review CT findings associated with solid organ, bowel, mesenteric, and diaphragmatic injury. In particular, emphasis is placed on the use of multidetector CT technology (MDCT), especially 64-row detector CT. The role of various techniques, including the use of oral and intravenous contrast, as well as the potential benefit of delayed imaging, is discussed.

64 MDCT in multiple trauma patients: imaging manifestations and clinical implications of active extravasation

The finding of active hemorrhage on computed tomography (CT) in trauma patients has been shown to have significant clinical implications and has been incorporated into numerous CT grading schema. As CT technology has advanced, the sensitivity for detection of active hemorrhage in the trauma population has significantly improved. Currently, with the improved spatial and temporal resolution afforded by 64 multidetector computed tomography (64 MDCT) technology, the clinical implications of the CT findings of active extravasation may need to be reconsidered. This article illustrates the various imaging manifestations of active extravasation throughout the body using 64 MDCT. Additionally, protocol issues specific to the findings of active hemorrhage using 64 MDCT are detailed, including novel interpretation techniques, which offer aid in detecting and characterizing hemorrhage. Finally, the clinical implication of active extravasation using this new technology is discussed. Although more sensitive to the detection of small hemorrhagic foci and with clinical implications highly dependent upon location, active bleeding remains as a salient finding that affects subsequent clinical management of trauma patients.