Imaging of renal trauma: a comprehensive review

Advancements in Trauma-Induced Acute Kidney Injury: Diagnostic and Therapeutic Innovations

Acute kidney injury following trauma impacts patient recovery critically, necessitating an integrated approach to emergency care and nephrology. This review aims to provide a comprehensive understanding of trauma-induced nephropathy, highlighting recent advancements in pathophysiological insights, diagnostic techniques, and strategic interventions. Our key findings emphasize the role of biomarkers, like Neutrophil Gelatinase-Associated Lipocalin and Liver Fatty Acid-Binding Protein, and imaging techniques, such as contrast-enhanced ultrasound, in early AKI detection. Preventive strategies, including aggressive fluid resuscitation, avoidance of nephrotoxic agents, and hemodynamic optimization, are essential for mitigating AKI progression. Integrating these approaches into trauma care frameworks aims to enhance patient outcomes and set a foundation for future research and clinical improvements.

The Japanese Urological Association's clinical practice guidelines for urotrauma 2023

The Japanese Urological Association's guidelines for the treatment of renal trauma were published in 2016. In conjunction with its revision, herein, we present the new guidelines for overall urotrauma. Its purpose is to provide standard diagnostic and treatment recommendations for urotrauma, including iatrogenic trauma, to preserve organ function and minimize complications and fatality. The guidelines committee comprised urologists with experience in urotrauma care, selected by the Trauma and Emergency Medicine Subcommittee of the Specialty Area Committee of the Japanese Urological Association, and specialists recommended by the Japanese Association for the Surgery of Trauma and the Japanese Society of Interventional Radiology. The guidelines committee established the domains of renal and ureteral, bladder, urethral, and genital trauma, and determined the lead person for each domain. A total of 30 clinical questions (CQs) were established for all domains; 15 for renal and ureteral trauma and five each for the other domains. An extensive literature search was conducted for studies published between January 1, 1983 and July 16, 2020, based on the preset keywords for each CQ. Since only few randomized controlled trials or meta-analyses were found on urotrauma clinical practice, conducting a systematic review and summarizing the evidence proved challenging; hence, the grade of recommendation was determined according to the 2007 "Minds Handbook for Clinical Practice Guidelines" based on a consensus reached by the guidelines committee. We hope that these guidelines will be useful for clinicians in their daily practice, especially those involved in urotrauma care.

Role of Functional SPECT and PET in Renal Emergencies

Renal scintigraphy is a centerpiece of nuclear medicine and is also commonly applied for (peri-)acute care. In this regard, referrals by the treating physician include: I.) acute obstructions caused by gradual and infiltrative tumor growth or renal off-target effects under anti-tumor treatment, II.) functional issues in infants, for example, structural abnormalities such as duplex kidneys or uroliths in adults, which can also trigger III.) Infections of renal parenchyma. Renal radionuclide imaging is also requested due to IV.) acute trauma to the abdomen, for example, to assess renal scarring or upon further follow-up after reconstructive surgery. We will discuss clinical applications of (peri-)acute renal scintigraphy, along with future prospects on the use of more advanced nuclear imaging techniques such as renal positron emission tomography.

Infarcts and ischemia in the abdomen: an imaging perspective with an emphasis on cross-sectional imaging findings

Infarcts and ischemia of abdominal organs may present with acute abdominal pain, and early diagnosis is crucial to prevent morbidity and mortality. Unfortunately, some of these patients present in poor clinical conditions to the emergency department, and imaging specialists are crucial for optimal outcomes. Although the radiological diagnosis of abdominal infarcts is often straightforward, it is vital to use the appropriate imaging modalities and correct imaging techniques for their detection. Additionally, some non-infarct-related abdominal pathologies may mimic infarcts, cause diagnostic confusion, and result in delayed diagnosis or misdiagnosis. In this article, we aimed to outline the general imaging approach, present cross-sectional imaging findings of infarcts and ischemia in several abdominal organs, including but not limited to, liver, spleen, kidneys, adrenals, omentum, and intestinal segments with relevant vascular anatomy, discuss possible differential diagnoses and emphasize important clinical/radiological clues that may assist radiologists in the diagnostic process.

CT findings in renovascular injuries following abdominal trauma: a pictorial review

Renal vascular injuries are more devastating than parenchymal injuries alone, thus account for higher injury grade and require prompt recognition. Revised AAST organ injury scale (OIS) for renal trauma has incorporated CT-diagnosed vascular injuries into renal injury grading which includes pseudoaneurysm and arteriovenous fistula, along with addition of some new descriptors of renovascular injury. Dual-phase contrast-enhanced CT (with both arterial and venous phase) can easily pick up renovascular injuries and is the modality of choice for imaging renovascular trauma. Radiologist should be well versed with the imaging findings of renovascular injuries so that accurate injury grading can be done and further management can be planned at the earliest.

Imaging Utilization Patterns and Injury Characteristics Associated with Electric Standing Scooters in a Major Urban Area

BACKGROUND

The recent proliferation of electric standing scooters in major urban areas of the United States has been accompanied by injuries of varying severity and nature, representing a growing public health concern.

OBJECTIVE

Our aim was to characterize imaging utilization patterns for injuries associated with electric scooter (e-scooter) use, including their initial emergency department (ED) management.

METHODS

We conducted a retrospective review of the electronic medical record for all patients presenting to affiliated EDs for e-scooter-related injuries between July 2018 and April 2020. Demographics, date and time of presentation, imaging study type, resultant injury, and procedural details were recorded.

RESULTS

Ninety-seven patients were included; mean age was 27.6 years. Of these, 55 patients (57%) had injuries identified on imaging and 40% of all imaging studies were positive. Most identified injuries (61%) were musculoskeletal, with a small number of neurological (2%) and genitourinary (1%) injuries. The highest prevalence of presentations occurred in August; most patients (72%) presented between 3 pm and 1 am and granular peaks were between 12 am and 1 am and 5 pm and 6 pm.

CONCLUSIONS

Patients presenting with e-scooter injuries have a high likelihood of injury to the radial head, nasal bone, and malleoli. Emergency physicians should be especially vigilant for injuries in these areas at presentation. Visceral injuries are uncommon but may be severe enough to warrant surgery.

Contrast-enhanced ultrasound of blunt abdominal trauma in children

Trauma is the leading cause of morbidity and mortality in children, and rapid identification of organ injury is essential for successful treatment. Contrast-enhanced ultrasound (CEUS) is an appealing alternative to contrast-enhanced CT in the evaluation of children with blunt abdominal trauma, mainly with respect to the potential reduction of population-level exposure to ionizing radiation. This is particularly important in children, who are more vulnerable to the hazards of ionizing radiation than adults. CEUS is useful in hemodynamically stable children with isolated blunt low- to moderate-energy abdominal trauma to rule out solid organ injuries. It can also be used to further evaluate uncertain contrast-enhanced CT findings, as well as in the follow-up of conservatively managed traumatic injuries. CEUS can be used to detect abnormalities that are not apparent by conventional US, including infarcts, pseudoaneurysms and active bleeding. In this article we present the current experience from the use of CEUS for the evaluation of pediatric blunt abdominal trauma, emphasizing the examination technique and interpretation of major abnormalities associated with injuries in the liver, spleen, kidneys, adrenal glands, pancreas and testes. We also discuss the limitations of the technique and offer a review of the major literature on this topic in children, including an extrapolation of experience from adults.

Renal Subcapsular Hematoma Formation Due to Hydronephrosis Caused by Recurrent Uterine Cervical Cancer

Most non-traumatic renal subcapsular hematomas are found in the presence of primary or metastatic renal tumors, or in the presence of vascular disease of the renal blood vessels. We managed an asymptomatic renal subcapsular hematoma that formed due to uterine cervical cancer that metastasized to the left common iliac lymph nodes. A 48-year-old woman with stage IB1 cervical cancer underwent neoadjuvant chemotherapy and concurrent chemoradiation following a radical hysterectomy. Six months after the completion of her first treatment, she developed left-sided hydronephrosis, a left subcapsular hematoma and left common iliac lymph nodes enlargement as demonstrated with contrast-enhanced computed tomography. Although a renal subcapsular hematoma is rarely a symptom of cervical cancer recurrence, it should be considered if other neoplastic or vascular diseases are ruled out.

Post-Traumatic Intraparenchymal Renal Hemorrhages: Correlation between CT and DSA Vascular Findings for Superselective Embolization Procedures

BACKGROUND

This study aims to investigate the correlation between computed tomography (CT) and digital subtraction angiography (DSA) findings in patients affected by acute post-traumatic intraparenchymal renal hemorrhages and evaluate their conservative management with superselective embolization.

METHODS

This retrospective multicenter analysis focuses on patients affected by renal bleedings detected by contrast-enhanced CT and treated with superselective endovascular embolization. CT findings were compared to DSA. Embolization procedural data were analyzed and renal function was evaluated before and after the intervention.

RESULTS

Twenty-seven patients were retrospectively evaluated in one year. Compared to DSA, CT showed 96.3% diagnostic accuracy in terms of hemorrhage recognition; concerning the type of vascular lesion, there was discrepancy between CT and DSA in five cases. The technical success rate of embolization was 100%, while primary clinical success was 88.9%. The inferior parenchymal third was the most frequent site of renal injury. Microcoils were the most adopted embolics. Renal function did not change significantly before and after embolization.

CONCLUSIONS

CT has elevated diagnostic accuracy in detecting post-traumatic intraparenchymal renal hemorrhages; in a small percentage, the type of vascular lesion may differ from the findings observed at DSA. In this scenario, superselective embolization presents high clinical success with a low complication rate.

A bizarre case of fatal main renal artery partial laceration without primary kidney injury due to a single stab wound in the chest

Reno-vascular injuries are a rare type of renal injury, and their second most frequent cause is penetrating wounds. The majority of the reports and of the studies are present in the urological and radiological literature and they focus on the clinical approach to such injuries. In the case here presented, an 18-year-old male died after being stabbed in the left hemithorax. During body examination, thoracic organs were found to be unremarkable (except for a small peripheral laceration of the left lung), but the diaphragm was transfixed and the upper wall of the left main renal artery was lacerated. The adjacent renal vein, the kidney, the aorta, the vena cava and the surrounding internal structures were not damaged (except for a small laceration of the pancreatic tail). A massive haemothorax and a large retroperitoneal haematoma in the left kidney area were observed. The cause of death was attributed to haemorrhagic shock following a partial laceration of the left main renal artery due to the stab wound to the chest. No other cases of similar fatal renovascular injuries due to stab wounds have been published in the current forensic literature.

Value of repeat CT for nonoperative management of patients with blunt liver and spleen injury: a systematic review

PURPOSE

To evaluate the effectiveness of routine repeat computed tomography (CT) for nonoperative management (NOM) of adults with blunt liver and/or spleen injury.

METHODS

We conducted a systematic review of randomized and non-randomized controlled trials (RCTs), quasi-experimental and observational studies of repeat CT in adult patients with blunt abdominal injury. We searched Medline, Embase, Web of Science, and Cochrane Central from their inception to October 2020 using Cochrane guidelines. Primary outcomes were change in clinical management (e.g., emergency surgery, embolization, blood transfusion, clinical surveillance), mortality, and complications. Secondary outcomes were hospital readmission and length of stay.

RESULTS

Search results yielded 1611 studies of which 28 studies including 2646 patients met our inclusion criteria. The majority reported on liver (n = 9) or spleen injury (n = 16) or both (n = 3). No RCTs were identified. Meta-analyses were not possible because no study performed direct comparisons of study outcomes across intervention groups. Only seven of the twenty-eight studies reported whether repeat CT was routine or prompted by clinical indication. In these 7 studies, among the 254 repeat CT performed, 188 (74%) were routine and 8 (4%) of these led to a change in clinical management. Of the 66 (26%) repeated CT prompted by clinical indication, 31 (47%) led to a change in management. We found no data allowing comparison of any other outcomes across intervention groups.

CONCLUSION

Routine repeat CT without clinical indication is not useful in the management of patients with liver and/or spleen injury. However, effect estimates were imprecise and included studies were of low methodological quality. Given the risks of unnecessary radiation and costs associated with repeat CT, future research should aim to estimate the frequency of such practices and assess practice variation.

LEVEL OF EVIDENCE

Systematic reviews and meta-analyses, Level II.

Traumatic renal artery dissection: from imaging to management

Injury to the renal artery following blunt trauma is detected increasingly due to widespread and early use of multidetector computed tomography (CT), but optimal treatment remains controversial as no guidelines are available. This review illustrates the spectrum of imaging findings of traumatic renal artery dissection based on our experience, with the aim of understanding the physiopathology of ischaemic damage to the kidney, and the process of choosing the best therapeutic strategy (conservative, endovascular, surgical). Five main patterns of traumatic renal artery dissection are described: avulsion of renal hilum; dissection of the segmental renal branches; preocclusive main renal artery dissection; renal artery stenosis without flow limitation; thrombogenic renal artery intimal tear. In the polytrauma patient, management depends on various factors (haemodynamic status, associated lesions, time of diagnosis) rather than on the degree of renal artery stenosis. Non-operative management (NOM) is the preferred option in case of non-flow-limiting dissection of the renal artery and angio-embolisation is an important adjunct to NOM in cases of active bleeding. Embolisation of the renal artery stump may be the best option in cases of occlusive dissection, as catheter manipulation carries a high risk of vessel rupture. The therapeutic window for kidney revascularisation in cases of flow-limiting dissection of main renal artery may be variable. Endovascular stenting >4 h after trauma should be performed only if residual flow with preserved parenchymal perfusion is detected at angiography. Antiplatelet therapy administration is recommended in cases of stenting, but conditioned by the bleeding risk of the patient.

Review of Multimodality Imaging of Renal Trauma

Blunt trauma accounts for more than 95% of traumatic renal injury and results from shear forces from rapid acceleration or deceleration and/or collision against the spine or ribs. The use of multiphasic contrast-enhanced computed tomography (CT) has proven pivotal in the evaluation and management of traumatic kidney injury, and CT imaging features provide the basis for nonsurgical staging. This article describes the epidemiology and mechanisms of blunt and penetrating traumatic renal injury and reviews the range of findings from various imaging modalities, with a particular emphasis on contrast-enhanced CT.

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

BACKGROUND

Excretory phase computed tomography (CT) scan is used for diagnosis of renal collecting system injuries and accurate grading of high-grade renal trauma. However, optimal timing of the excretory phase is not well established. We hypothesized that there is an association between excretory phase timing and diagnosis of urinary extravasation and aimed to identify the optimal excretory phase timing for diagnosis of urinary extravasation.

METHODS

The Genito-Urinary Trauma Study collected data on high-grade renal trauma (grades III-V) from 14 Level I trauma centers between 2014 and 2017. The time between portal venous and excretory phases at initial CT scans was recorded. Poisson regression was used to measure the association between excretory phase timing and diagnosis of urinary extravasation. Predictive receiver operating characteristic analysis was used to identify a cutoff point optimizing detection of urinary extravasation.

RESULTS

Overall, 326 patients were included; 245 (75%) had excretory phase CT scans for review either initially (n = 212) or only at their follow-up (n = 33). At initial CT with excretory phase, 46 (22%) of 212 patients were diagnosed with urinary extravasation. Median time between portal venous and excretory phases was 4 minutes (interquartile range, 4-7 minutes). Time of initial excretory phase was significantly greater in those diagnosed with urinary extravasation. Increased time to excretory phase was positively associated with finding urinary extravasation at the initial CT scan after controlling for multiple factors (risk ratio per minute, 1.15; 95% confidence interval, 1.09-1.22; p < 0.001). The optimal delay for detection of urinary extravasation was 9 minutes.

CONCLUSION

Timing of the excretory phase is a significant factor in accurate diagnosis of renal collecting system injury. A 9-minute delay between the early and excretory phases optimized detection of urinary extravasation.

LEVEL OF EVIDENCE

Diagnostic tests/criteria study, level III.

Post-Traumatic Ostial Avulsion of a Polar Inferior Renal Artery Treated by Endovascular Covered Aortic Stenting

Renovascular traumas are rare in abdominal blunt traumas, especially those involving complete avulsion of a renal artery. Their management poses a dilemma between blood flow preservation and the risks of bleeding. We present the case of a rare variant of renovascular injury, with a post traumatic ostial avulsion of a polar inferior renal artery, successfully treated percutaneously by endovascular aortic covered stenting under c-arm cone-beam computed tomography guiding.

Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review

The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.^©RSNA, 2019.

Delayed Rupture of the Renal Collecting System Secondary to a Traumatic Hemorrhage in the Setting of Suspected Chronic Ureteropelvic Junction Obstruction

Isolated rupture of the renal pelvis secondary to blunt trauma is rare, though there is increased incidence in the setting of a pre-existing renal abnormality that predisposes the kidney to injury. We report a case of post-traumatic hemorrhage into the renal collecting system leading to delayed rupture of the renal pelvis in the setting of suspected chronic ureteropelvic junction obstruction. This case illustrates the difficulty in diagnosis of acute hemorrhage into the renal collecting system. Special attention should be given to a kidney with a pre-existing abnormality in the setting of trauma to prevent complications. A literature review of hemorrhage into the collecting system along with appropriate imaging and management are discussed.

Traumatic kidney injuries: A systematic review and meta-analysis

BACKGROUND

Traumatic kidney injury is an infrequent event with a wide range of injury patterns. The aim of this paper is to review the incidence, mechanisms of injury, diagnostic methods, and therapeutic indications of renal injury according to the most recent evidence and to perform an analysis of mortality rates on these patients.

OBJECTIVES

To perform a systematic review of the literature and a meta-analysis on traumatic kidney injuries.

DATA SOURCES

A literature search was performed using PubMed, Embase, and Scopus databases. Articles published in English, French and Spanish were selected from 1963 to 2018. MeSH terms utilized were renal trauma, kidney trauma, blunt renal trauma, and penetrating renal trauma.

STUDY PARTICIPANTS

The eligibility criteria included only original and human subject articles. Articles not involving human patients, cancer related, review articles, surveys, iatrogenic injuries, pediatric patients, and case reports were excluded from this search.

RESULTS

Forty-six articles met the inclusion criteria of which 48,660 patients were identified and included in this review. Gender was reported in 32,918 cases, of which 75.3% of patients were male with a mean age of 33 years. Of the 44,865 patients where the mechanism of injury was described, we identified 36,086 (80.5%) patients that sustained blunt trauma, while 8,779 (19.5%) were due to penetrating mechanisms. Twenty one series with a total of 31,689 patients included the mortality rate. Overall mortality rate with exact binomial 95% confidence interval estimated via random effects model was 6.4% (4.8%-8.4%).

CONCLUSIONS

Non-operative management has become the standard in renal trauma management with good results in morbidity and mortality. This has resulted in a decrease in the number of unnecessary iatrogenic nephrectomies and potential improvement in a patient's quality of life. When an invasive treatment is necessary, angioembolization for active bleeding or nephrorrhaphy is usually sufficient.

Kidney and uro-trauma: WSES-AAST guidelines

Renal and urogenital injuries occur in approximately 10-20% of abdominal trauma in adults and children. Optimal management should take into consideration the anatomic injury, the hemodynamic status, and the associated injuries. The management of urogenital trauma aims to restore homeostasis and normal physiology especially in pediatric patients where non-operative management is considered the gold standard. As with all traumatic conditions, the management of urogenital trauma should be multidisciplinary including urologists, interventional radiologists, and trauma surgeons, as well as emergency and ICU physicians. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and the American Association for the Surgery of Trauma (AAST) kidney and urogenital trauma management guidelines.

The American Association for the Surgery of Trauma Organ Injury Scale 2018 update for computed tomography-based grading of renal trauma: a primer for the emergency radiologist

The most widely used trauma injury grading system is the Organ Injury Scale (OIS) by the American Association for the Surgery of Trauma (AAST). The AAST OIS for renal trauma was revised in 2018 to reflect necessary updates based on decades of experience with computed tomography (CT)-based injury diagnosis and, specifically, to better incorporate vascular injuries, which were not comprehensively addressed in the original OIS. In this review article, we describe CT findings of the AAST OIS for the kidney according to the 2018 revision, with an emphasis on real-world application, and highlight important differences from the prior grading scheme. Routine use of this grading system allows for a standardized classification of the range of renal injuries to aid in management, adding value in the imaging care of trauma patients.

Contrast-enhanced ultrasound (CEUS) in pediatric blunt abdominal trauma

Baseline ultrasound is the first-choice technique in traumatic hemodynamically stable children, and is essential in the early assessment of unstable patients to detect hemoperitoneum or other potentially fatal conditions. Despite the technological advancements in new ultrasound equipment and the experience of the operators, it is not always possible to rule out the presence of parenchymal traumatic lesions by means of baseline ultrasound nor to suspect them, especially in the absence of hemoperitoneum. For this reason, in the last decades, basic ultrasound has been associated with contrast-enhanced ultrasound (CEUS) to evaluate the stable little patient in cases such as low-energy blunt abdominal trauma. Because it relies on second-generation contrast agents, the CEUS technique allows for better detection of parenchymal injuries. CEUS has been demonstrated to be almost as sensitive as contrast-enhanced CT in the detection of traumatic injuries in patients affected by low-energy isolated abdominal trauma, with levels of sensitivity and specificity up to 95%. A very important point in favor of CEUS is its capacity to help distinguish the healthy patient, who can be discharged, from the one needing prolonged monitoring, operative management or hospitalization. Finally, we also have the ability to follow-up on low-grade traumatic lesions using CEUS, always keeping in mind patients' clinical conditions and their hemodynamics.

Automated Kidney Segmentation for Traumatic Injured Patients through Ensemble Learning and Active Contour Modeling

Traumatic abdominal injury can lead to multiple complications including laceration of major organs such as kidneys. Contrast-enhanced Computed Tomography (CT) is the primary imaging modality for evaluating kidney injury. However, the traditional visual examination of CT scans is time consuming, non-quantitative, prone to human error, and costly. In this work we propose a kidney segmentation method using machine learning and active contour modeling. We first detect an initialization mask inside the kidney and then evolve its boundary. This model is specifically developed and evaluated on trauma cases. Our experimental results show the average recall score of 92.6% and average Dice similarity value of 88.9%.

Blunt trauma of unilateral intraperitoneal kidney: A case report

The kidney is located and fixed with Gerota's fascia in the retroperitoneal space and is surrounded by a fat pad that acts as a shock absorber in the normal anatomy; however, the kidney becomes more vulnerable to external shock when it is located intraperitoneally. Bleeding from an injury may advance to hemoperitoneum and unstable hemodynamics may develop, requiring emergency surgery. Although various anatomical variations of the kidney have been reported, to our knowledge, an intraperitoneal kidney has never been reported previously except for one case in the world literature. This paper describes a successful nephrectomy of a unilateral intraperitoneal kidney in a 69-year-old woman who had grade IV laceration based on the renal injury scale of the American Association for the Surgery of Trauma with unstable hemodynamics after blunt trauma.

Renal trauma: the current best practice

The kidneys are the most vulnerable genitourinary organ in trauma, as they are involved in up to 3.25% of trauma patients. The most common mechanism for renal injury is blunt trauma (predominantly by motor vehicle accidents and falls), while penetrating trauma (mainly caused by firearms and stab wound) comprise the rest. High-velocity weapons impose specifically problematic damage because of the high energy and collateral effect. The mainstay of renal trauma diagnosis is based on contrast-enhanced computed tomography (CT), which is indicated in all stable patients with gross hematuria and in patients presenting with microscopic hematuria and hypotension. Additionally, CT should be performed when the mechanism of injury or physical examination findings are suggestive of renal injury (e.g. rapid deceleration, rib fractures, flank ecchymosis, and every penetrating injury of the abdomen, flank or lower chest). Renal trauma management has evolved during the last decades, with a distinct evolution toward a nonoperative approach. The lion's share of renal trauma patients are managed nonoperatively with careful monitoring, reimaging when there is any deterioration, and the use of minimally invasive procedures. These procedures include angioembolization in cases of active bleeding and endourological stenting in cases of urine extravasation.

Delayed manifestations of abdominal trauma: follow-up abdominopelvic CT in posttraumatic patients

PURPOSE

Our study aims to investigate the frequency and patterns of delayed manifestations of abdominal and pelvic injuries which may not be identified or which fail to manifest on the initial abdominopelvic CT in posttraumatic patients.

METHODS

For our institutional review board (IRB)-approved retrospective study, our hospital trauma registry was queried for patients with blunt multitrauma and Injury Severity Score (ISS) ≥ 16 between January 2010 and August 2016, yielding 3735 patients. A total of 203 patients received a follow-up abdominopelvic CT within six months from the initial scan and those with new findings on follow-up CT were identified. A retrospective blinded review of the initial CT examinations was performed by two experienced radiologists. The retrospective readings and original reports were compared to categorize the new abnormalities detected on follow-up CT scans. The categories included missed injuries, late presentations and sequelae of trauma, and complications of surgery, hospital admission, and invasive procedures. The patients' notes were reviewed for the clinical indications, time interval for repeat CT examination, and subsequent clinical management. The software used for statistical analysis of the extracted data was Microsoft Excel for Mac (version 15.33).

RESULTS

Out of 3735 patients, 203 patients received 232 follow-up abdominopelvic CTs. The average elapsed time between the initial CT and the follow-up CT was 15 ± 27 days. Evaluation for an abdominal fluid collection was the most common clinical indication, accounting for 40% of the total number (n = 243) of indications. Delayed manifestations and complications of trauma were present in 41 patients due to 47 abnormalities, most commonly related to solid organ injury, followed by abdominal collections and hematoma. Twenty-nine CT findings (62%) were only detectable on follow-up CT, while nine injuries (19%) were missed on initial CT. The findings on repeated CT warranted eight surgical and 15 interventional procedures.

CONCLUSION

A small percentage of traumatic injuries may be unidentified or fail to manifest on the initial CT, resulting in delayed manifestations of abdominopelvic trauma, which may lead to subsequent readmission, delayed management, and more severe medical complications.

Page kidney secondary to subcapsular hematoma following percutaneous renal allograft biopsy

Percutaneous renal biopsy with ultrasound guidance is a helpful procedure regularly performed to obtain renal tissue diagnosis for rejection in the postrenal transplant setting; however, it is not without risks. We report the case of a 42-year-old male with end stage renal disease who developed a subcapsular hematoma, with subsequent hypertension and renal failure, compatible with acute page kidney as a complication of the renal biopsy. The ultrasound images demonstrated classic imaging appearances which all diagnostic and interventional radiologists should be aware of. The patient was managed successfully with conventional open surgical evacuation of the hematoma with return to baseline laboratories and vital signs after the procedure.

The diagnosis and management of renal trauma

Background:

Renal trauma is less common but often occurs in polytrauma. Most trauma is blunt and the severity of the injury varies in different circumstances.

Assessment:

There is a series of features that should prompt investigation but none are reliably seen in all trauma cases and a low threshold for suspecting renal injury should be taken. A urine dip is essential.

Investigation:

Computerised tomography is the main modality. Follow-up imaging may be used if complications arise and ultrasound may be used in some cases.

Management:

Approaches include surgical, radiological and conservative. The latter has been achieved in all grades but intervention will be required in haemodynamic instability.

Complications:

Haemorrhage, infection and urine extravasation are common and require intervention. There are many long-term complications and hypertension can occur by a variety of mechanisms.

Imaging Genitourinary Trauma

Contrast-enhanced multidetector computed tomography (MDCT) has become a critical tool in the evaluation of the trauma patient. MDCT can quickly and accurately assess trauma patients for renal, ureteral, and bladder injuries. Moreover, CT guides clinical management triaging patients to those requiring discharge, observation, angioembolization, and surgery. Recognition of urinary tract trauma on initial scan acquisition should prompt delayed excretory phase imaging to identify urine leaks. Urethral and testicular trauma are imaged with retrograde urethrography and sonography, respectively.

Concurrent use of endourological and radiologic methods in the management of high-grade renal trauma

This case report explores the efficacy of simultaneous use of endourological and radiological methods to assess and manage high-grade renal trauma. A male rugby player was diagnosed with Grade 4 blunt renal trauma. A segment of the patient's kidney was isolated from the main renal pelvis with intact perfusion. This resulted in urinary extravasation. Ureteral stenting and angioembolization were used to treat the patient's severe symptoms. Angioembolization ablated functional tissue that was causing a persistent urinary leak. Following the treatment, the patient was discharged with no significant bleeding or leakage from the kidney. This report illustrates an uncommon use of this combined approach. Followup 18 months post-trauma revealed normal blood pressure and approximately 30% loss of volume of the affected kidney.

Diagnostic imaging of blunt abdominal trauma in pediatric patients

Trauma is a leading cause of morbidity and mortality in childhood, and blunt trauma accounts for 80-90 % of abdominal injuries. The mechanism of trauma is quite similar to that of the adults, but there are important physiologic differences between children and adults in this field, such as the smaller blood vessels and the high vasoconstrictive response, leading to the spreading of a non-operative management. The early imaging of children undergoing a low-energy trauma can be performed by CEUS, a valuable diagnostic tool to demonstrate solid organ injuries with almost the same sensitivity of CT scans; nevertheless, as for as urinary tract injuries, MDCT remains still the technique of choice, because of its high sensitivity and accuracy, helping to discriminate between an intra-peritoneal form a retroperitoneal urinary leakage, requiring two different managements. The liver is the most common organ injured in blunt abdominal trauma followed by the spleen. Renal, pancreatic, and bowel injuries are quite rare. In this review we present various imaging findings of blunt abdominal trauma in children.

Incidence of benign results after laparoscopic radical nephroureterectomy

BACKGROUND AND OBJECTIVES

Studies of patients with benign pathologic lesions who underwent laparoscopic radical nephroureterectomy (RNU) with preoperative suspicion of upper urinary tract urothelial carcinoma are lacking. The aim of this retrospective cross-sectional study was to evaluate the incidence of benign pathologic lesions on laparoscopic RNU for upper urinary tract tumors that are presumed to be urothelial carcinoma. The clinicopathologic characteristics of these lesions were also determined.

METHODS

Between January 2004 and December 2010, 244 patients underwent laparoscopic RNU for possible upper urinary tract urothelial carcinoma at our institute. Seven (2.9%) had benign lesions at the final pathologic examination. The preoperative features of these patients were investigated, including imaging findings, urine cytologic results, and ureteroscopic findings.

RESULTS

The 7 patients comprised 5 men and 2 women. The lesions were located in the ureter in 5 patients and in the renal pelvis in 2. All patients underwent preoperative voided urine cytology and cystoscopy. Two patients underwent preoperative ureteroscopy. In 1 patient, definite pathologic lesions were not identified in the surgical specimen. Urinary tract tuberculosis was diagnosed in 1 patient, inflammatory pseudotumor in 2, and fibroepithelial polyps in 1. In 2 patients, stones were detected (stone with atypical papillary urothelial hyperplasia and polypoid ureteritis with ureter stone, respectively) after laparoscopic RNU.

CONCLUSION

Benign pathologic lesions were detected in 7 patients (2.9%) who had undergone laparoscopic RNU for upper urinary tract tumors that were presumed to be urothelial carcinoma. The description of these false-positive cases will help improve the preoperative counseling of these patients.

Renal Trauma: The Rugby Factor

INTRODUCTION

Renal trauma accounts for 5% of all trauma cases. Rare mechanisms of injuries including sports participation are increasingly common. Rugby-related trauma poses a conundrum for physicians and players due to the absence of clear guidelines and a paucity of evidence. Our series highlights traumatic rugby-related renal injuries in our institution, and emphasize the need for international guidelines on management.

METHODS

A retrospective review of all abdominal traumas between January 2006 and April 2013, specifically assessing for renal related trauma that were secondary to rugby injuries was performed. All patients' demographics, computerized tomography results, hematological and biochemical results and subsequent management were recorded.

RESULTS

Five male patients presented with rugby-related injuries. Mean age was 21 years old. All patients were hemodynamically stable and managed conservatively in acute setting. One patient was detected to have an unknown pre-existing atrophic kidney that had been subsequently injured, and was booked for an elective nephrectomy an 8-week interval.

CONCLUSION

Rugby-related trauma has generated essential attention. This paper serves to highlight this type of injury and the need for defined guidelines on role of imaging and international consensus on timing of return to contact sport, in both professional and amateur settings.

Intrathoracic Kidney after Blunt Abdominal Trauma: A Case Report and Review of the Literature

Abdominal trauma is responsible for most genitourinary injuries. The incidence of renal artery injury and intrathoracic kidney is quite low in patients who present with blunt trauma experiencing damage. There are four defined etiologies for intrathoracic kidney, which include real intrathoracic ectopic kidney, eventration of the diaphragm, congenital diaphragmatic herniation, and traumatic diaphragmatic rupture. The traumatic intrathoracic kidney is an extremely rare case. We presented intrathoracic kidney case after traumatic posterior diaphragmatic rupture.

[Infectious diseases and injuries of bladder and urinary tract]

Urinary tract infections are the most common infectious diseases in Germany. In most cases clarification does not rely on imaging techniques other than sonography and is made mostly based on clinical symptoms. Computed tomography (CT) and magnetic resonance imaging (MRI) can be used in selected cases to find the cause and detection or exclusion of complications, e.g. recurrent or atypical and complicated courses. The method of choice for clarification of urolithiasis is CT. Using low-dose techniques, detection or exclusion of urinary stones can be achieved with a high sensitivity and specificity as well as an acceptable level of radiation exposure. Native stone CT supplies additional fundamental information that can substantially influence further therapy planning. The diagnosis of ureteral injuries is clinically and radiologically not trivial and clarification is aided by urographic contrast media. The method of CT cystography has an important role in the diagnostics of urinary bladder injuries.

Imaging of Urinary System Trauma

Computed tomography (CT) imaging of the kidney, ureter, and bladder permit accurate and prompt diagnosis or exclusion of traumatic injuries, without the need to move the patient to the fluoroscopy suite. Real-time review of imaging permits selective delayed imaging, reducing time on the scanner and radiation dose for patients who do not require delays. Modifying imaging parameters to obtain thicker slices and noisier images permits detection of contrast extravasation from the kidneys, ureters, and bladder, while reducing radiation dose on the delayed or cystographic imaging. The American Association for the Surgery of Trauma grading system is discussed, along with challenges and limitations.