Optimal timing of delayed excretory phase computed tomography scan for diagnosis of urinary extravasation after high-grade renal trauma

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.

Imaging modalities and management of pediatric high-grade renal trauma in an Indonesian tertiary hospital: a report of two cases and literature review

As one of the most commonly injured organs in the genitourinary system during trauma, a thorough understanding of pediatric renal trauma's diagnosis and management is essential for physicians. The improvement of imaging modalities in recent years has shifted most treatments to a conservative approach. Non-operative management could reduce the risk of nephrectomy while increasing renal salvage rate. However, high-grade pediatric renal injury management remains controversial. We aimed to report two children with high-grade renal trauma, diagnosed using computed tomography and retrograde pyelography studies, undergoing different approaches. The first patient underwent a nephrectomy, whereas the second patient underwent non-operative management.

Non-operatively managed blunt and penetrating renal trauma: Does early follow up CT scan change management? A systematic review

BACKGROUND

Renal injury accounts for 1-5% of all traumatic injuries. Non-operative management (NOM) of renal trauma has demonstrated higher renal salvage rates and reduced morbidity.

AIMS

The aim of this review is to clarify the indications of early follow up CT scan for adult patients, with NOM, renal trauma, with a view to avoiding unnecessary CT scanning and radiation exposure in this cohort of patients.

METHODS

A systematic search was conducted using PubMed (MEDLINE), Web of Science, Embase, and Cochrane library, with references from relevant articles also evaluated. Inclusion criteria were defined as studies reporting outcomes of patients ≥12 years of age, with NOM, renal trauma and early CT re-imaging. The outcomes of interest were renal complications requiring intervention, specifically collecting system and vascular complications.

RESULTS

Five studies met the inclusion criteria. In total, 542 patients were included in this analysis; study sizes ranged from 48 to 207 patients. Early re-imaging was performed for 510 patients, including 489 CTs and 31 Ultrasounds (US). Mean time to re-imaging ranged from 1 - 35.9 days. Twenty three patients required intervention following re-imaging, all of which were for injuries grade ≥ 3 and presented with clinical deterioration prior to re-imaging, had a collecting system injury identified on initial CT scan or both. The number needed to re-image, in order to change the management of one patient, was 22.

CONCLUSIONS

Although the findings of this review are based on retrospective data, they suggest routine early re-imaging can be safely omitted for all NOM, renal injuries which remain asymptomatic, with no collecting system injury diagnosed on initial CT, provided appropriate delayed phase imaging is available. Future prospective studies are required to further clarify the indications of early re-imaging, specifically for NOM penetrating injuries, and the appropriate modality and timing of early re-imaging for all NOM renal trauma.

Iterative reconstruction improves image quality and reduces radiation dose in trauma protocols; A human cadaver study

Background

Radiation-related cancer risk is an object of concern in CT of trauma patients, as these represent a young population. Different radiation reducing methods, including iterative reconstruction (IR), and spilt bolus techniques have been introduced in the recent years in different large scale trauma centers.

Purpose

To compare image quality in human cadaver exposed to thoracoabdominal computed tomography using IR and standard filtered back-projection (FBP) at different dose levels.

Material and methods

Ten cadavers were scanned at full dose and a dose reduction in CTDIvol of 5 mGy (low dose 1) and 7.5 mGy (low dose 2) on a Siemens Definition Flash 128-slice computed tomography scanner. Low dose images were reconstructed with FBP and Sinogram affirmed iterative reconstruction (SAFIRE) level 2 and 4. Quantitative image quality was analyzed by comparison of contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). Qualitative image quality was evaluated by use of visual grading regression (VGR) by four radiologists.

Results

Readers preferred SAFIRE reconstructed images over FBP at a dose reduction of 40% (low dose 1) and 56% (low dose 2), with significant difference in overall impression of image quality. CNR and SNR showed significant improvement for images reconstructed with SAFIRE 2 and 4 compared to FBP at both low dose levels.

Conclusions

Iterative image reconstruction, SAFIRE 2 and 4, resulted in equal or improved image quality at a dose reduction of up to 56% compared to full dose FBP and may be used a strong radiation reduction tool in the young trauma population.

The Current Role of Interventional Radiology in the Management of Acute Trauma Patient

Trauma is one of the most common causes of death, particularly in younger individuals. The development of specialized trauma centers, trauma-specific intensive care units, and trauma-focused medical subspecialties has led to the formation of comprehensive multidisciplinary teams and an ever-growing body of research and innovation. The field of interventional radiology provides a unique set of minimally invasive, endovascular techniques that has largely changed the way that many trauma patients are managed. This article discusses the role of interventional radiology in the care of this complex patient population, and in particular how the specialty fits into the overall team management of these patients.

On the Binormal Predictive Receiver Operating Characteristic Curve for the Joint Assessment of Positive and Negative Predictive Values

The predictive receiver operating characteristic (PROC) curve is a diagrammatic format with application in the statistical evaluation of probabilistic disease forecasts. The PROC curve differs from the more well-known receiver operating characteristic (ROC) curve in that it provides a basis for evaluation using metrics defined conditionally on the outcome of the forecast rather than metrics defined conditionally on the actual disease status. Starting from the binormal ROC curve formulation, an overview of some previously published binormal PROC curves is presented in order to place the PROC curve in the context of other methods used in statistical evaluation of probabilistic disease forecasts based on the analysis of predictive values; in particular, the index of separation (PSEP) and the leaf plot. An information theoretic perspective on evaluation is also outlined. Five straightforward recommendations are made with a view to aiding understanding and interpretation of the sometimes-complex patterns generated by PROC curve analysis. The PROC curve and related analyses augment the perspective provided by traditional ROC curve analysis. Here, the binormal ROC model provides the exemplar for investigation of the PROC curve, but potential application extends to analysis based on other distributional models as well as to empirical analysis.

Coming Together: A Review of the American Association for the Surgery of Trauma's Updated Kidney Injury Scale to Facilitate Multidisciplinary Management

OBJECTIVE. The purpose of this article is to review the renal injury scale revised by the American Association for the Surgery of Trauma in 2018, to identify terms commonly used in discussions between radiologists and surgeons and to properly apply the new classification parameters to various MDCT findings. CONCLUSION. The updated 2018 kidney injury scale from the American Association for the Surgery of Trauma incorporates the delineations necessary for modern nonoperative management of renal trauma, including percutaneous and endourologic techniques, and discusses the imaging criteria for each injury grade.