PROPOSED REVISION OF THE AMERICAN ASSOCIATION FOR SURGERY OF TRAUMA RENAL TRAUMA ORGAN INJURY SCALE: SECONDARY ANALYSIS OF THE MULTI-INSTITUTIONAL GENITOURINARY TRAUMA STUDY.

BACKGROUND: This study updates the American Association for Surgery of Trauma (AAST) Organ Injury Scale (OIS) for renal trauma using evidence-based criteria for bleeding control intervention. METHODS: This was a secondary analysis of a multi-center retrospective study including patients with high grade renal trauma from 7 Level-1 trauma centers from 2013-2018. All eligible patients were assigned new renal trauma grades based on revised criteria. The primary outcome used to measure injury severity was intervention for renal bleeding. Secondary outcomes included intervention for urinary extravasation, units of packed red blood cells (PRBCs) transfused within 24 hours, and mortality. To test the revised grading system, we performed mixed effect logistic regression adjusted for multiple baseline demographic and trauma covariates. We determined the area under the receiver-operator curve (AUC) to assess accuracy of predicting bleeding interventions from the revised grading system and compared this to 2018 AAST organ injury scale. RESULTS: based on the 2018 OIS grading system, we included 549 patients with AAST Grade III-V injuries and CT scans (III: 52% (n = 284), IV: 45% (n = 249), and V: 3% (n = 16)). Among these patients, 89% experienced blunt injury (n = 491) and 12% (n = 64) underwent intervention for bleeding. After applying the revised grading criteria, 60% (n = 329) of patients were downgraded and 4% (n = 23) were upgraded; 2.8% (n = 7) downgraded from grade V to IV, and 69.5% (n = 173) downgraded from IV to III. The revised renal trauma grading system demonstrated improved predictive ability for bleeding interventions (2018 AUC = 0.805, revised AUC = 0.883; p = 0.001) and number of units of PRBCs transfused. When we removed urinary injury from the revised system, there was no difference in its predictive ability for renal hemorrhage intervention. CONCLUSIONS: A revised renal trauma grading system better delineates the need for hemostatic interventions than the current AAST OIS renal trauma grading system. LEVEL OF EVIDENCE: II.

CT imaging of intrauterine devices (IUD): expected findings, unexpected findings, and complications.

Intrauterine devices (IUDs) are a commonly used form of long-acting reversible contraception, which either contain copper or levonorgestrel to prevent pregnancy. Although symptomatic patients with indwelling IUDs may first undergo ultrasound to assess for device malposition and complications, IUDs are commonly encountered on CT in patients undergoing evaluation for unrelated indications. Frequently, IUD malposition and complications may be asymptomatic or clinically unsuspected. For these reasons, it is important for the radiologist to carefully scrutinize the IUD on any study in which it is encountered. To do so, the radiologist must recognize that normally positioned IUDs are located centrally within the uterine cavity. IUDs are extremely effective in preventing pregnancy, though inadvertent pregnancy risk is higher with malpositioned IUDs. Presence of fibroids or Mullerian abnormalities may preclude proper IUD placement. Radiologists play an important role in identifying complications when they arise and special considerations when planning for an IUD placement. There is a wide range of IUD malposition, affecting IUDs differently depending on the type of IUD and its mechanism of action. IUD malposition is the most common complication, but embedment and/or partial perforation can and can lead to difficulty when removed. Retained IUD fragments can result in continued contraceptive effect. Perforated IUDs do not typically cause intraperitoneal imaging findings.

Shattered Kidney After Renal Trauma: Should It Be Classified As an American Association for the Surgery of Trauma Grade V Injury?

OBJECTIVE: To study the prevalence and management of shattered kidney and to evaluate if the new description of "loss of identifiable renal anatomy" in the 2018 American Association for the Surgery of Trauma (AAST) organ injury scale (OIS) would improve the ability to predict bleeding control interventions. METHODS: We used high-grade renal trauma data from 21 Level-1 trauma centers from 2013 to 2018. Initial CT scans were reviewed to identify shattered kidneys, defined as a kidney having ≥3 parenchymal fragments displaced by blood or fluid on cross-sectional imaging. We further categorized patients with shattered kidney in two models based on loss of identifiable renal parenchymal anatomy and presence or absence of vascular contrast extravasation (VCE). Bleeding interventions were compared between the groups. RESULTS: From 861 high-grade renal trauma patients, 41 (4.8%) had shattered kidney injury. 25 (61%) underwent a bleeding control intervention including 18 (43.9%) nephrectomies and 11 (26.8%) angioembolizations. 18 (41%) had shattered kidney with "loss of identifiable parenchymal renal anatomy" per 2018 AAST OIS (model-1). 28 (68.3%) had concurrent VCE (model-2). Model-2 had a statistically significant improvement in area under the curve over model-1 in predicting bleeding interventions (0.75 vs 0.72; P = .01). CONCLUSION: Shattered kidney is associated with high rates of active bleeding, urinary extravasation, and interventions including nephrectomy. The definition of shattered kidney is vague and subjective and our definition might be simpler and more reproducible. Loss of identifiable renal anatomy per the 2018 AAST OIS did not provide better distinction for bleeding control interventions over presence of VCE.

Grade V renal trauma management: results from the multi-institutional genito-urinary trauma study.

PURPOSE: To investigate management trends for American Association for the Surgery of Trauma (AAST) grade V renal trauma with focus on non-operative management. METHODS: We used prospectively collected data as part of the Multi-institutional Genito-Urinary Trauma Study (MiGUTS). We included patients with grade V renal trauma according to the AAST Injury Scoring Scale 2018 update. All cases submitted by participating centers with radiology images available were independently reviewed to confirm renal trauma grade. Management was classified as expectant, conservative (minimally invasive, endoscopic or percutaneous procedures), or operative (renal-related surgery). RESULTS: Eighty patients were included, 25 of whom had complete imaging and had independent confirmation of AAST grade V renal trauma. Median age was 35 years (Interquartile range (IQR) 25-50) and 23 (92%) had blunt trauma. Ten patients (40%) were managed operatively with nephrectomy. Conservative management was used in nine patients (36%) of which six received angioembolization and three had a stent or drainage tube placed. Expectant management was followed in six (24%) patients. Transfusion requirements were progressively higher with groups requiring more aggressive treatment, and injury characteristics differed significantly across management groups in terms of hematoma size and laceration size. Vascular contrast extravasation was more likely in operatively managed patients though a statistically significant association was not found. CONCLUSION: Successful use of nonoperative management for grade V injuries is used for a substantial subset of patients. Lower transfusion requirement and less severe injury radiologic phenotype appear to be important characteristics delineating this group.

Malignant Germ Cell Tumors of the Ovary: Clinical and Imaging Features.

Ovarian malignant germ cell tumors are a diverse set of masses originating from the primitive gonadal germ cells, often in young females. They have useful imaging and clinical features, including serum tumor marker elevation, that may aid the radiologist at the time of diagnosis, and also during follow-up. Accurate and timely diagnosis is essential, as standard-of-care therapies lead to a high rate of cancer remission.

Lost in descent: Complications of cryptorchidism.

Cryptorchidism is a relatively common and important clinical entity and can lead to an array of downstream complications if it is not corrected in a timely manner, most notably with the development of testicular germ cell tumors. However, beyond the development of malignancy, there are other rare complications associated with cryptorchid testicular germ cell tumors which are more commonly seen in females with ovarian germ cell tumors, including torsion, rupture, and paraneoplastic syndromes. Presented is an instructive case (with literature review) of a patient who presented with NMDA encephalitis due to a torsed mixed germ cell tumor of an undescended testis, which subsequently ruptured leading to growing teratoma syndrome.

Insulin Receptor-Expressing T Cells Appear in Individuals at Risk for Type 1 Diabetes and Can Move into the Pancreas in C57BL/6 Transgenic Mice.

Insulin receptor (IR) expression on the T cell surface can indicate an activated state; however, the IR is also chemotactic, enabling T cells with high IR expression to physically move toward insulin. In humans with type 1 diabetes (T1D) and the NOD mouse model, a T cell-mediated autoimmune destruction of insulin-producing pancreatic ß cells occurs. In previous work, when purified IR+ and IR- T cells were sorted from diabetic NOD mice and transferred into irradiated nondiabetic NOD mice, only those that received IR+ T cells developed insulitis and diabetes. In this study, peripheral blood samples from individuals with T1D (new onset to 14 y of duration), relatives at high-risk for T1D, defined by positivity for islet autoantibodies, and healthy controls were examined for frequency of IR+ T cells. High-risk individuals had significantly higher numbers of IR+ T cells as compared with those with T1D (p < 0.01) and controls (p < 0.001); however, the percentage of IR+ T cells in circulation did not differ significantly between T1D and control subjects. With the hypothesis that IR+ T cells traffic to the pancreas in T1D, we developed a (to our knowledge) novel mouse model exhibiting a FLAG-tagged mouse IR on T cells on the C57BL/6 background, which is not susceptible to developing T1D. Interestingly, these C57BL/6-CD3FLAGmIR/mfm mice showed evidence of increased IR+ T cell trafficking into the islets compared with C57BL/6 controls (p < 0.001). This transgenic animal model provides a (to our knowledge) novel platform for investigating the influence of IR expression on T cell trafficking and the development of insulitis.

Multiple enlarging hepatic and retroperitoneal myelolipomas in the setting of Cushing disease.

Myelolipomas are benign tumours typically occurring in the adrenal glands, made up of fat and trilineage haematopoeitic cells resembling bone marrow. Their aetiology is not well understood; however, they have a clear association with elevated serum adrenocorticotropic hormone (ACTH). Extra-adrenal myelolipomas are rare, and to our knowledge there are no previously reported cases of multiple enlarging hepatic and retroperitoneal myelolipomas in the setting of Cushing disease. We present the case of a patient with an ACTH-producing pituitary adenoma who developed multiple enlarging fat containing lesions in the liver and retroperitoneum, which were histologically proven multifocal myelolipomas.

External validation of a nomogram predicting risk of bleeding control interventions after high-grade renal trauma: The Multi-institutional Genito-Urinary Trauma Study.

BACKGROUND: Renal trauma grading has a limited ability to distinguish patients who will need intervention after high-grade renal trauma (HGRT). A nomogram incorporating both clinical and radiologic factors has been previously developed to predict bleeding control interventions after HGRT. We aimed to externally validate this nomogram using multicenter data from level 1 trauma centers. METHODS: We gathered data from seven level 1 trauma centers. Patients with available initial computed tomography (CT) scans were included. Each CT scan was reviewed by two radiologists blinded to the intervention data. Nomogram variables included trauma mechanism, hypotension/shock, concomitant injuries, vascular contrast extravasation (VCE), pararenal hematoma extension, and hematoma rim distance (HRD). Mixed-effect logistic regression was used to assess the associations between the predictors and bleeding intervention. The prediction accuracy of the nomogram was assessed using the area under the receiver operating characteristic curve and its 95% confidence interval (CI). RESULTS: Overall, 569 HGRT patients were included for external validation. Injury mechanism was blunt in 89%. Using initial CT scans, 14% had VCE and median HRD was 1.7 (0.9-2.6) cm. Overall, 12% underwent bleeding control interventions including 34 angioembolizations and 24 nephrectomies. In the multivariable analysis, presence of VCE was associated with a threefold increase in the odds of bleeding interventions (odds ratio, 3.06; 95% CI, 1.44-6.50). Every centimeter increase in HRD was associated with 66% increase in odds of bleeding interventions. External validation of the model provided excellent discrimination in predicting bleeding interventions with an area under the curve of 0.88 (95% CI, 0.84-0.92). CONCLUSION: Our results reinforce the importance of radiologic findings such as VCE and hematoma characteristics in predicting bleeding control interventions after renal trauma. The prediction accuracy of the proposed nomogram remains high using external data. These variables can help to better risk stratify high-grade renal injuries. LEVEL OF EVIDENCE: Prognostic and epidemiological study, level III.

The American Association for the Surgery of Trauma Renal Grading System-Should Segmental Kidney Infarction be Classified as a Grade IV Injury?

PURPOSE: In 2018 the American Association for the Surgery of Trauma revised renal injury grading. One change was inclusion of segmental kidney infarction under grade IV injuries. We aimed to assess how segmental kidney infarction will change the scope of grade IV injuries and compare bleeding control interventions in those with and without isolated segmental kidney infarction. METHODS: We used high grade renal trauma data from 7 level 1 trauma centers from 2013 to 2018 as part of the Multi-institutional Genito-Urinary Trauma Study. Initial computerized tomography scans were reviewed to regrade the injuries. Injuries were categorized as isolated segmental kidney infarction if segmental parenchymal infarction was the only reason for inclusion under grade IV injury. All other grade IV injuries (including combined injury patterns) were categorized as without isolated segmental kidney infarction. Bleeding interventions were compared between those with and without isolated segmental kidney infarction. RESULTS: From 550 patients with high grade renal trauma and available computerized tomography, 250 (45%) were grade IV according to the 2018 American Association for the Surgery of Trauma grading system. Of these, 121 (48%) had isolated segmental kidney infarction. The majority of patients with isolated segmental kidney infarction (88%) would have been assigned a lower grade using the original 1989 grading system. Rate of bleeding control interventions was lower in isolated segmental kidney infarction compared to other grade IV injuries (7% vs 21%, p=0.002). Downgrading all patients with isolated segmental kidney infarction to grade III did not change the grading system's associations with bleeding interventions. CONCLUSIONS: Approximately half of the 2018 American Association for the Surgery of Trauma grade IV injuries have isolated segmental kidney infarction. Including isolated segmental kidney infarction in grade IV injuries increases the heterogeneity of these injuries without increasing the grading system's ability to predict bleeding interventions. In future iterations of the American Association for the Surgery of Trauma renal trauma grading isolated segmental kidney infarction could be reclassified as grade III injury.

Clinical and Radiographic Factors Associated With Failed Renal Angioembolization: Results From the Multi-institutional Genitourinary Trauma Study (Mi-GUTS).

OBJECTIVE: To find clinical or radiographic factors that are associated with angioembolization failure after high-grade renal trauma. MATERIAL AND METHODS: Patients were selected from the Multi-institutional Genito-Urinary Trauma Study. Included were patients who initially received renal angioembolization after high-grade renal trauma (AAST grades III-V). This cohort was dichotomized into successful or failed angioembolization. Angioembolization was considered a failure if angioembolization was followed by repeat angiography and/or an exploratory laparotomy. RESULTS: A total of 67 patients underwent management initially with angioembolization, with failure in 18 (27%) patients. Those with failed angioembolization had a larger proportion ofgrade IV (72% vs 53%) and grade V (22% vs 12%) renal injuries. A total of 53 patients underwent renal angioembolization and had initial radiographic data for review, with failure in 13 cases. The failed renal angioembolization group had larger perirenal hematoma sizes on the initial trauma scan. CONCLUSION: Angioembolization after high-grade renal trauma failed in 27% of patients. Failed angioembolization was associated with higher injury grade and a larger perirenal hematoma. Likely these characteristics are associated with high-grade renal trauma that may be less amenable to successful treatment after a single renal angioembolization.

Radiographic and Endoscopic Features of Pancreaticoduodenal Malakoplakia.

Malakoplakia is a rare, granulomatous disorder that is typically triggered by infections in immunocompromised patients. Although it most commonly affects the urinary tract, cases may occasionally occur in the gastrointestinal tract. There are case reports of malakoplakia of the pancreas with associated pathologic description, but none with detailed imaging and endoscopic findings. In addition, description of magnetic resonance imaging characteristics of mass-forming malakoplakia in the literature is sparse. We present a case of pancreaticoduodenal malakoplakia in an immunocompromised patient, including detailed description of magnetic resonance imaging, computed tomography, and endoscopic findings with radiology-pathology correlation. Classic pathologic features of malakoplakia (eg, hypercellularity, inflammation, and mineralization of Michaelis-Gutmann bodies) lead to specific features on imaging, such as marked diffusion restriction, heterogeneous enhancement, calcification, and increased attenuation on nonenhanced computed tomography. These features may help differentiate malakoplakia from other more common lesions that occur in this location, especially if present in an immunocompromised patient.

Acute Ureteral Obstruction by Deeply Inserted Menstrual Cup.

Mechanical complications from menstrual cups are rare, with only four reported cases of ureteral obstruction. Clinicians should be aware of gynecologic devices in patients with acute abdominopelvic pain because simple removal may obviate the need for further expensive work-up or exposure to ionizing radiation.

The American Association for the Surgery of Trauma renal injury grading scale: Implications of the 2018 revisions for injury reclassification and predicting bleeding interventions.

BACKGROUND: In 2018, the American Association for the Surgery of Trauma (AAST) published revisions to the renal injury grading system to reflect the increased reliance on computed tomography scans and non-operative management of high-grade renal trauma (HGRT). We aimed to evaluate how these revisions will change the grading of HGRT and if it outperforms the original 1989 grading in predicting bleeding control interventions. METHODS: Data on HGRT were collected from 14 Level-1 trauma centers from 2014 to 2017. Patients with initial computed tomography scans were included. Two radiologists reviewed the scans to regrade the injuries according to the 1989 and 2018 AAST grading systems. Descriptive statistics were used to assess grade reclassifications. Mixed-effect multivariable logistic regression was used to measure the predictive ability of each grading system. The areas under the curves were compared. RESULTS: Of the 322 injuries included, 27.0% were upgraded, 3.4% were downgraded, and 69.5% remained unchanged. Of the injuries graded as III or lower using the 1989 AAST, 33.5% were upgraded to grade IV using the 2018 AAST. Of the grade V injuries, 58.8% were downgraded using the 2018 AAST. There was no statistically significant difference in the overall areas under the curves between the 2018 and 1989 AAST grading system for predicting bleeding interventions (0.72 vs. 0.68, p = 0.34). CONCLUSION: About one third of the injuries previously classified as grade III will be upgraded to grade IV using the 2018 AAST, which adds to the heterogeneity of grade IV injuries. Although the 2018 AAST grading provides more anatomic details on injury patterns and includes important radiologic findings, it did not outperform the 1989 AAST grading in predicting bleeding interventions. LEVEL OF EVIDENCE: Prognostic and Epidemiological Study, level III.

Peripheral hypervascularity of the corpus luteum with ovarian edema (CLOE) may decrease false positive diagnoses of ovarian torsion.

INTRODUCTION: In patients with pelvic pain, corpus luteum with associated ovarian edema (CLOE) may be mistaken for ovarian torsion on ultrasound or CECT. METHODS: This was a multi-reader, blinded, retrospective review performed at a single academic center from 2012 to 2018. Cases of CLOE that were misdiagnosed as torsion and cases of ovarian torsion without a lead-point mass were analyzed. Evaluated ultrasound features included presence of a corpus luteum, ovarian and corpus luteum volume, Color Doppler vascularity of the corpus luteum rim compared to that of the ovarian stroma, peripheral follicular displacement, twisted vascular pedicle, and free fluid. Evaluated CT features included presence of a corpus luteum, ovarian and corpus luteum volume, corpus luteum rim enhancement, twisted vascular pedicle, and free fluid. RESULTS: 39 cases of CLOE and 30 cases of ovarian torsion without lead-point mass were reviewed. A corpus luteum was present in 56.7% of torsed ovaries. In CLOE cases, peripheral hypervascularity of the corpus luteum (manifested as enhancement at CECT or flow signal at Doppler US) was present in 67.7% (21/31) of cases on ultrasound, and in 95.7% (22/23) of cases on CT. No peripheral hypervascularity of the corpus luteum was seen in cases of torsion (p < 0.001). Torsed ovaries were significantly larger than CLOE cases. Other findings were not significantly different between the two groups. CONCLUSION: Increased blood flow in the periphery of a corpus luteum on color Doppler ultrasound or on CECT is a strong negative predictor for ovarian torsion.

The associations between initial radiographic findings and interventions for renal hemorrhage after high-grade renal trauma: Results from the Multi-Institutional Genitourinary Trauma Study.

BACKGROUND: Indications for intervention after high-grade renal trauma (HGRT) remain poorly defined. Certain radiographic findings can be used to guide the management of HGRT. We aimed to assess the associations between initial radiographic findings and interventions for hemorrhage after HGRT and to determine hematoma and laceration sizes predicting interventions. METHODS: The Genitourinary Trauma Study is a multicenter study including HGRT patients from 14 Level I trauma centers from 2014 to 2017. Admission computed tomography scans were categorized based on multiple variables, including vascular contrast extravasation (VCE), hematoma rim distance (HRD), and size of the deepest laceration. Renal bleeding interventions included angioembolization, surgical packing, renorrhaphy, partial nephrectomy, and nephrectomy. Mixed-effect Poisson regression was used to assess the associations. Receiver operating characteristic analysis was used to define optimal cutoffs for HRD and laceration size. RESULTS: In the 326 patients, injury mechanism was blunt in 81%. Forty-seven (14%) patients underwent 51 bleeding interventions, including 19 renal angioembolizations, 16 nephrectomies, and 16 other procedures. In univariable analysis, presence of VCE was associated with a 5.9-fold increase in risk of interventions, and each centimeter increase in HRD was associated with 30% increase in risk of bleeding interventions. An HRD of 3.5 cm or greater and renal laceration depth of 2.5 cm or greater were most predictive of interventions. In multivariable models, VCE and HRD were significantly associated with bleeding interventions. CONCLUSION: Our findings support the importance of certain radiographic findings in prediction of bleeding interventions after HGRT. These factors can be used as adjuncts to renal injury grading to guide clinical decision making. LEVEL OF EVIDENCE: Prognostic and Epidemiological Study, Level III and Therapeutic/Care Management, Level IV.

Intertidal clams exhibit population synchrony across spatial and temporal scales.

Long-term datasets can be particularly useful for parsing out factors influencing populations, yet few studies have utilized continuous datasets to quantify population dynamics in bivalve molluscs. We used dynamic factor analysis on a clam biomass dataset spanning 28 yr and five distinct regions in the southern Salish Sea to determine (1) if native intertidal clam populations exhibit synchrony and (2) what environmental covariates may be correlated with these population trends. Once covariates were accounted for, the model with the most data support included three predominant trends to describe multidecadal change in clam biomass. Intraspecific synchrony was highest among Saxidomus gigantea and Leukoma staminea populations, with no clear evidence of covariance in Clinocardium nuttallii. Specifically, we quantified a pronounced decadal decline in L. staminea and an increase in S. gigantea biomass on most beaches. No beaches showed synchrony in trends across all three species, indicating that species-specific trends (regardless of location) were more common than beach-specific trends (regardless of species). Seven environmental covariates were evaluated in their capacity to explain variability in annual mean biomass. Of these, the North Pacific Gyre Oscillation lagged 4 yr prior to the observation year was most supported by the data in the best fitting model, implying that 4 yr old clam biomass is partially determined by oceanographic processes affecting larval clams. Although results suggest large-scale density-independent factors play a role in venerid clam population dynamics, it is also likely local factors account for variability not explained by our model.

A nomogram predicting the need for bleeding interventions after high-grade renal trauma: Results from the American Association for the Surgery of Trauma Multi-institutional Genito-Urinary Trauma Study (MiGUTS).

BACKGROUND: The management of high-grade renal trauma (HGRT) and the indications for intervention are not well defined. The American Association for the Surgery of Trauma (AAST) renal grading does not incorporate some important clinical and radiologic variables associated with increased risk of interventions. We aimed to use data from a multi-institutional contemporary cohort to develop a nomogram predicting risk of interventions for bleeding after HGRT. METHODS: From 2014 to 2017, data on adult HGRT (AAST grades III-V) were collected from 14 level 1 trauma centers. Patients with both clinical and radiologic data were included. Data were gathered on demographics, injury characteristics, management, and outcomes. Clinical and radiologic parameters, obtained after trauma evaluation, were used to predict renal bleeding interventions. We developed a prediction model by applying backward model selection to a logistic regression model and built a nomogram using the selected model. RESULTS: A total of 326 patients met the inclusion criteria. Mechanism of injury was blunt in 81%. Median age and injury severity score were 28 years and 22, respectively. Injuries were reported as AAST grades III (60%), IV (33%), and V (7%). Overall, 47 (14%) underwent interventions for bleeding control including 19 renal angioembolizations, 16 nephrectomies, and 12 other procedures. Of the variables included in the nomogram, a hematoma size of 12 cm contributed the most points, followed by penetrating trauma mechanism, vascular contrast extravasation, pararenal hematoma extension, concomitant injuries, and shock. The area under the receiver operating characteristic curve was 0.83 (95% confidence interval, 0.81-0.85). CONCLUSION: We developed a nomogram that integrates multiple clinical and radiologic factors readily available upon assessment of patients with HGRT and can provide predicted probability for bleeding interventions. This nomogram may help in guiding appropriate management of HGRT and decreasing unnecessary interventions. LEVEL OF EVIDENCE: Prognostic and epidemiological study, level III.

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.