Imaging Patients with Kidney Failure.

The approach to imaging a patient with kidney failure continues to evolve. Overstatement of the risk of iodinated contrast material-induced (ie, contrast-induced) acute kidney injury and new guidelines for administration of gadolinium-based contrast media affect screening and the choice of contrast material. Treatment of kidney failure requires dialysis or a kidney transplant. Pretransplant imaging includes assessment for the feasibility of performing a transplant and evaluation for underlying malignancy and peripheral vascular disease. Patients with kidney failure are at high risk for renal cell carcinoma. Subtypes that occur exclusively or more commonly in patients with kidney failure, such as acquired cystic kidney disease, renal cell carcinoma, and clear cell papillary renal cell carcinoma, have specific clinical-pathologic characteristics, with indolent behavior. Performing US for dialysis planning increases the success of placement of an arteriovenous fistula, while postoperative US evaluation is essential in assessment of access dysfunction. Systemic manifestations in patients with kidney failure are multifactorial and may relate to the underlying cause of renal failure or may be secondary to treatment effects. Disturbances in mineral and bone metabolism and soft-tissue and vascular calcifications are seen in patients with chronic kidney disease and mineral bone disorder. Neurologic and cardiothoracic complications are also common. The authors provide a comprehensive overview of imaging considerations for patients with kidney failure, including the appropriate use of CT, MRI, and US with their respective contrast agents; the use of imaging in transplant workup and dialysis assessment; and the common renal and extrarenal manifestations of kidney failure. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Fetal Echocardiographic Variables Associated with Pre-Surgical Mortality in Truncus Arteriosus: A Pilot Study.

Truncus arteriosus (TA) is a rare congenital heart defect that can be prenatally detected by fetal echocardiography. However, prognostication and prenatal counseling focus primarily on surgical outcomes due to limited fetal and neonatal pre-surgical mortality data. We aimed to describe the incidence and identify predictors of pre-surgical mortality in prenatally detected TA. This two-center, retrospective cohort study included fetuses diagnosed with TA between 01/2010 and 04/2020. The primary outcome was pre-surgical mortality, defined by fetal or neonatal pre-surgical death or primary listing for transplantation prior to discharge. Univariable regression modeling, Chi-square tests, and t tests assessed for associations between prenatal clinical, demographic, and fetal echocardiographic (fetal-echo) variables and pre-surgical mortality. Of 23 pregnancies with prenatal diagnosis of TA, 4 (17%) were terminated. Of the remaining 19, pre-surgical mortality occurred in 4 (26%), including 2 (11%) fetal deaths and 2 (11%) neonatal pre-surgical deaths. No transplantation listings. Of liveborn fetuses (n = 17), 15 (88%) underwent a neonatal surgery, and 1 (6%) required ECMO. As compared to the survivors, the pre-surgical mortality group had a higher likelihood of having left ventricular dysfunction (0% vs. 40%; p = 0.01), right ventricular dysfunction (0% vs. 60%; p = 0.002), cardiovascular profile score < 7 (0% vs. 40%; p = 0.01), skin edema (0% vs. 40%; p = 0.01), and abnormal umbilical venous (UV) Doppler (0% vs. 60%; p = 0.002). The presence of truncal valve regurgitation or stenosis neared significance. In this cohort with prenatally diagnosed TA, there is significant pre-surgical mortality, including fetal death and neonatal pre-surgical death. Termination rate is also high. Fetal-echo variables associated with pre-surgical mortality in this cohort include ventricular dysfunction, low CVP, skin edema, and abnormal UV Doppler. Knowledge about prenatal risk factors for pre-surgical mortality may guide parental counseling and postnatal planning in prenatally diagnosed TA.

Aortic root dilation in adult patients with Marfan syndrome: Does aortic root stiffness matter?

Objective: Aortic root (AoR) size remains an imperfect predictor of rate of aortic dilation in Marfan syndrome (MFS). Indicators of vascular phenotype such as aortic stiffness have been proposed as additional predictors. In this study we assessed the rate of AoR dilation and stiffness in adult patients with MFS. Methods: We performed a retrospective chart review. We included adult patients with MFS (aged 20-40 years) with at least 2 local echocardiograms 6 months apart (no aortic surgery in-between). A blinded observer analyzed the echocardiograms. AoR dilation rate and stiffness were calculated. Results: Thirty-two patients (53% women; median age, 21.1; interquartile range [IQR], 19-24 years at first echocardiogram) were included. AoR dilation rate in the entire cohort was 0 to 8 mm/year (median, 0.465; IQR, 0.23-1.45 mm/year). Multiple linear regression analysis showed that baseline AoR stiffness was associated with AoR dilation rate (ß = 0.0004; P < .001 for elastic modulus), whereas baseline age and baseline AoR dimension were not. Eighteen of these 32 patients (56%) eventually had AoR surgery (Sx) and 14 did not have surgery (NSx). At baseline, Sx and NSx patients were similar in age. AoR dimension was larger (Sx, 4.27 cm; IQR, 4.05-4.49 cm vs NSx, 3.73 cm; IQR, 3.37-4.09 cm; P = .011) and AoR stiffness was higher in Sx patients (beta stiffness index: median, 23.2; IQR, 17.8-28.6 vs median, 15.6; IQR, 11.6-19.7; P = .024). AoR dilation rate was greater in Sx patients, independent of baseline AoR dimension (1.63 ± 0.41 mm/year vs 0.38 ± 0.08 mm/year; P = .01). Conclusions: Our results showed that AoR dilation rate varies among adult patients with MFS and is associated with baseline AoR stiffness, measured by echocardiography. Further studies are warranted to determine how aortic stiffness can be implemented clinically to refine management in patients with MFS.

Focal Nodular Hyperplasia and Focal Nodular Hyperplasia-like Lesions.

Focal nodular hyperplasia (FNH) is a benign lesion occurring in a background of normal liver. FNH is seen most commonly in young women and can often be accurately diagnosed at imaging, including CT, MRI, or contrast-enhanced US. In the normal liver, FNH frequently must be differentiated from hepatocellular adenoma, which although benign, is managed differently because of the risks of hemorrhage and malignant transformation. When lesions that are histologically identical to FNH occur in a background of abnormal liver, they are termed FNH-like lesions. These lesions can be a source of diagnostic confusion and must be differentiated from malignancies. Radiologists' familiarity with the imaging appearance of FNH-like lesions and knowledge of the conditions that predispose a patient to their formation are critical to minimizing the risks of unnecessary intervention for these lesions, which are rarely symptomatic and carry no risk for malignant transformation. FNH is thought to form secondary to an underlying vascular disturbance, a theory supported by the predilection for formation of FNH-like lesions in patients with a variety of hepatic vascular abnormalities. These include abnormalities of hepatic outflow such as Budd-Chiari syndrome, abnormalities of hepatic inflow such as congenital absence of the portal vein, and hepatic microvascular disturbances, such as those that occur after exposure to certain chemotherapeutic agents. Familiarity with the imaging appearances of these varied conditions and knowledge of their association with formation of FNH-like lesions allow radiologists to identify with confidence these benign lesions that require no intervention. Online supplemental material is available for this article. ©RSNA, 2022.

Multiinstitutional Evaluation of the Liver Surface Nodularity Score on CT for Staging Liver Fibrosis and Predicting Liver-Related Events in Patients With Hepatitis C.

BACKGROUND. In single-institution multireader studies, the liver surface nodularity (LSN) score accurately detects advanced liver fibrosis and cirrhosis and predicts liver decompensation in patients with chronic liver disease (CLD) from hepatitis C virus (HCV). OBJECTIVE. The purpose of this study was to assess the diagnostic performance of the LSN score alone and in combination with the (FIB-4; fibrosis index based on four factors) to detect advanced fibrosis and cirrhosis and to predict future liver-related events in a multiinstitutional cohort of patients with CLD from HCV. METHODS. This retrospective study included 40 consecutive patients, from each of five academic medical centers, with CLD from HCV who underwent nontargeted liver biopsy within 6 months before or after abdominal CT. Clinical data were recorded in a secure web-based database. A single central reader measured LSN scores using software. Diagnostic performance for detecting liver fibrosis stage was determined. Multivariable models were constructed to predict baseline liver decompensation and future liver-related events. RESULTS. After exclusions, the study included 191 patients (67 women, 124 men; mean age, 54 years) with fibrosis stages of F0-F1 (n = 37), F2 (n = 44), F3 (n = 46), and F4 (n = 64). Mean LSN score increased with higher stages (F0-F1, 2.26 ± 0.44; F2, 2.35 ± 0.37; F3, 2.42 ± 0.38; F4, 3.19 ± 0.89; p < .001). The AUC of LSN score alone was 0.87 for detecting advanced fibrosis (≥ F3) and 0.89 for detecting cirrhosis (F4), increasing to 0.92 and 0.94, respectively, when combined with FIB-4 scores (both p = .005). Combined scores at optimal cutoff points yielded sensitivity of 75% and specificity of 82% for advanced fibrosis, and sensitivity of 84% and specificity of 85% for cirrhosis. In multivariable models, LSN score was the strongest predictor of baseline liver decompensation (odds ratio, 14.28 per 1-unit increase; p < .001) and future liver-related events (hazard ratio, 2.87 per 1-unit increase; p = .03). CONCLUSION. In a multiinstitutional cohort of patients with CLD from HCV, LSN score alone and in combination with FIB-4 score exhibited strong diagnostic performance in detecting advanced fibrosis and cirrhosis. LSN score also predicted future liver-related events. CLINICAL IMPACT. The LSN score warrants a role in clinical practice as a quantitative marker for detecting advanced liver fibrosis, compensated cirrhosis, and decompensated cirrhosis and for predicting future liver-related events in patients with CLD from HCV.

The Effect of Exenatide Once Weekly on Carotid Atherosclerosis in Individuals With Type 2 Diabetes: An 18-Month Randomized Placebo-Controlled Study.

OBJECTIVE: Glucagon-like peptide 1 receptor agonists (GLP-1RAs) improved multiple proatherogenic risk factors and reduced cardiovascular events in recent clinical trials, suggesting that they may slow progression of atherosclerosis. We tested whether exenatide once weekly reduces carotid plaque progression in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: In a double-blind, pragmatic trial, 163 participants were randomized (2:1) to exenatide (n = 109) or placebo (n = 54). Changes in carotid plaque volume and composition were measured at 9 and 18 months by multicontrast 3 Tesla MRI. Fasting and post-high-fat meal plasma glucose and lipids, and endothelial function responses, were measured at 3, 9, and 18 months. RESULTS: Exenatide reduced hemoglobin A1c (HbA1c) (estimated difference vs. placebo 0.55%, P = 0.0007) and fasting and postmeal plasma glucose (19 mg/dL, P = 0.0002, and 25 mg/dL, P < 0.0001, respectively). Mean (SD) change in plaque volume in the exenatide group (0.3% [2%]) was not different from that in the placebo group (-2.2% [8%]) (P = 0.4). The change in plaque volume in the exenatide group was associated with changes in HbA1c (r = 0.38, P = 0.0004), body weight, and overall plasma glucose (r = 0.29, P = 0.007 both). There were no differences in changes in plaque composition, body weight, blood pressure, fasting and postmeal plasma triglycerides, and endothelial function between the groups. CONCLUSIONS: Exenatide once weekly for up to 18 months improved fasting and postprandial glycemic control but did not modify change in carotid plaque volume or composition. This study raises the possibility that short-term antiatherosclerotic effects may not play a central role in the cardiovascular benefits of GLP-1RAs.

Using qualitative descriptors of chronic liver disease on MRI: A practice prone to error.

PURPOSE: Assess accuracy of qualitative descriptors for chronic liver disease (CLD) in radiology reports compared to histopathological staging. METHODS: Database search for patients with hepatitis B/C (HBV/HCV) CLD, abdominal MRI during 2009-2016, and liver biopsy within 6 months of MRI or prior biopsy showing cirrhosis. Reports reviewed for mention of CLD and associated descriptors. Findings stratified into categories: normal/no mention of CLD; changes of CLD without qualitative descriptor; mild/early; moderate; severe/advanced and cirrhosis. Descriptive ranges categorized to the lesser degree. Percent concordance/discordance of descriptors and Scheuer stage (F0-F4), false positive (FP), false negative (FN) and sensitivity/specificity calculated. RESULTS: 309 patients, median age 54 (24-74). 91% had HCV (282/309), 7% HBV and 2% both HBV/HCV. Biopsy showed 19% without CLD/F0; 8% F1, 15% F2, 15% F3 and 43% F4. 188 MRI reports (61%) stated CLD was present; however, 16 had no fibrosis on histopathology (9% FP). 39% (121/309) did not mention or stated no CLD; however, 78 had CLD on histopathology (64% FN). 59% of FN were early fibrosis (F1 or F2), 27% F3 and 11% F4. Overall sensitivity and specificity was 69% and 73%, respectively. 77% (145/188) of MRI reports used a descriptive qualifier when describing CLD. 10% were concordant with exact histopathology staging. Of discordant reports, 90% identified CLD but under-called severity. CONCLUSION: Abdominal radiologists can detect CLD on MRI but degree of CLD is often under-called compared to histopathology suggesting radiologists should refrain from qualitative descriptors in assessing CLD on MRI and reaffirms the need for quantitative imaging.

The Natural and Unnatural History of Ventricular Septal Defects Presenting in Infancy: An Echocardiography-Based Review.

BACKGROUND: Ventricular septal defect (VSD), the most common congenital heart defect, accounts for 40% of heart malformations. Despite this prevalence, there remains no consensus on the utility of echocardiography to guide modern-era treatment. In this study, we evaluated patients with isolated VSDs to test the hypothesis that echocardiographic evidence of left ventricular (LV) volume overload and type of VSD are associated with surgical intervention and to identify useful echocardiographic indicators for management of VSDs in infants and children. METHODS: We reviewed 350 patients with VSDs diagnosed during the first year of life. Echocardiographic measurements were made at the time of diagnosis and at the endpoint. The VSD area was calculated using inner edge to inner edge dimensions obtained from two planes and indexed to body surface area. Aortic annulus dimension, left atrium to aortic root ratio, LV end-diastolic diameter, left atrial volume, VSD velocity-time integral, ejection fraction, and pulmonary to systemic blood flow ratio (Qp:Qs) were measured using conventional methods. RESULTS: One hundred seventy-seven muscular (50.5%) and 162 perimembranous (46%) VSDs accounted for the vast majority of defects. Only seven (4%) muscular defects required surgical closure, while 76 (47%) perimembranous defects required surgery. Indexed VSD area, VSD to aortic valve ratio, indexed left atrium volume, LV end-diastolic diameter, VSD velocity-time integral, and Qp:Qs at diagnosis were significantly different between the surgical and nonsurgical groups. Ventricular septal defect area > 50 mm2/m2 at initial diagnosis was independently associated with risk for surgery (P = .0055). CONCLUSIONS: Indexed VSD area is an echocardiographic variable that can be easily measured at diagnosis and can provide insight into the likelihood of requiring surgical intervention regardless of the type and location of the defect.

"Echo pause" for postoperative transthoracic echocardiographic surveillance.

BACKGROUND: No guidelines exist for inpatient postoperative transthoracic echocardiographic (TTE) surveillance in congenital heart disease. We prospectively evaluated indications for postoperative TTEs in patients with congenital heart disease to identify areas to improve upon (Phase 1) and then assessed the impact of a simple pilot intervention (Phase 2). METHODS: We included patients with RACHS-1 (Risk Adjustment for Congenital Heart Surgery) scores of 2 and 3 to keep the cohort homogenous. During Phase 1, we collected data prospectively to identify postoperative TTEs for which there were no new findings and no associated clinical management decisions ("potentially redundant" TTEs). During Phase 2, prior to placement of a TTE order, an "Echo Pause" was performed during rounds to prompt review of prior TTE results and indication for the current order. The number of "potentially redundant" TTEs during Phase 1 vs. Phase 2 was compared. RESULTS: During Phase 1, 98 postoperative TTEs were performed on 51 patients. Potentially "redundant" TTEs were identified in two main areas: (a) TTEs ordered to evaluate pericardial effusion and (b) TTEs ordered with the indication of "postoperative," "follow-up," or "discharge" in the setting of a prior complete postoperative TTE and no apparent change in clinical status. During Phase 2, 101 TTEs were performed on 63 patients. The number of "potentially redundant" TTEs decreased from 14/98 (14%) to 5/101 (5%) (P = .026). CONCLUSION: Our results suggest that the number of "potentially redundant" TTEs during inpatient postoperative surveillance of patients with congenital heart disease can be decreased by a simple intervention during rounds such as an "Echo Pause."

Active Surveillance Versus Nephron-Sparing Surgery for a Bosniak IIF or III Renal Cyst: A Cost-Effectiveness Analysis.

OBJECTIVE: The objective of our study was to evaluate the cost-effectiveness of active surveillance (AS) versus nephron-sparing surgery (NSS) in patients with a Bosniak IIF or III renal cyst. MATERIALS AND METHODS: Markov models were developed to estimate life expectancy and lifetime costs for 60-year-old patients with a Bosniak IIF or III renal cyst (the reference cases) managed by AS versus NSS. The models incorporated the malignancy rates, reclassification rates during follow-up, treatment effectiveness, complications and costs, and short- and long-term outcomes. An incremental cost-effectiveness analysis was performed to identify management preference under an assumed $75,000 per quality-adjusted life-year (QALY) societal willingness-to-pay threshold, using data from studies in the literature and the 2015 Medicare Physician Fee Schedule. The effects of key parameters were addressed in a multiway sensitivity analysis. RESULTS: The prevalence of malignancy for Bosniak IIF and III renal cysts was 26% (25/96) and 52% (542/1046). Under base case assumptions for Bosniak IIF cysts, the incremental cost-effectiveness ratio of NSS relative to AS was $731,309 per QALY for women, exceeding the assumed societal willingness-to-pay threshold, and AS outperformed NSS for both life expectancy and cost for men. For Bosniak III cysts, AS yielded greater life expectancy (24.8 and 19.4 more days) and lower lifetime costs (cost difference of $12,128 and $11,901) than NSS for men and women, indicating dominance of AS over NSS. Superiority of AS held true in sensitivity analyses for men 46 years old or older and women 57 years old or older even when all parameters were set to favor NSS. CONCLUSION: AS is more cost-effective than NSS for patients with a Bosniak IIF or III renal cyst.

An integrated framework using high-dimensional mass cytometry and fluorescent flow cytometry identifies discrete B cell subsets in patients with red meat allergy.

BACKGROUND: B cells play a critical role in the development and maintenance of food allergy by producing allergen-specific IgE. Despite the importance of B cells in IgE-mediated food allergy, the identity of sIgE-producing human B cells and how IgE is regulated are poorly understood. OBJECTIVE: To identify the immunophenotypes of circulating B cells associated with the production of galactose-alpha-1,3-galactose-specific IgE production in patients with red meat allergy. METHODS: B cells in PBMC samples obtained from 19 adults with physician-diagnosed red meat allergy and 20 non-meat allergic healthy controls were assessed by mass cytometry along with a bioinformatics analysis pipeline to identify discrete B cell phenotypes that associated with serum sIgE. Fluorescent flow cytometry was then applied to sort purify discrete B cell subsets, and B cells were functionally evaluated on an individual cell level for the production of sIgE by ELISPOT. RESULTS: Discrete B cell phenotypes abundant in meat allergic subjects compared to non-meat allergic controls were found in peripheral blood that do not share typical characteristics of classical isotype-switched memory B cells that express high levels of CD27. These B cell subsets shared higher IgD and lower IgM expression levels coupled with CXCR4, CCR6 and CD25 expression. In vitro polyclonal stimulation of purified B cell subsets from meat allergic subjects demonstrated that these subsets were enriched for cells induced to secrete sIgE. CONCLUSIONS AND CLINICAL RELEVANCE: Circulating B cells display increased abundance of discrete B cell subsets in meat allergic subjects. This observation, coupled with the capacity of individual B cell subsets to produce sIgE following activation, implicates these novel B cell phenotypes in promoting IgE in meat allergy.

Abdominal Imaging Surveillance in Adult Patients After Fontan Procedure: Risk of Chronic Liver Disease and Hepatocellular Carcinoma.

PURPOSE: To assess the prevalence of chronic liver disease (CLD) and hepatocellular carcinoma (HCC) in adult patients who had surveillance imaging after Fontan procedure. METHODS: Institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study evaluated electronic medical records including radiology reports and clinical notes for adult patients after Fontan procedure between January 1993 and January 2016. Abdominal ultrasound, computed tomography, and magnetic resonance imaging reports were reviewed for changes of CLD and HCC. Existence of concomitant viral hepatitis was also recorded. RESULTS: A total of 145 patients (male: 78 and female: 67) had surveillance imaging after Fontan procedure. In all, 78% (113/145) had ongoing imaging surveillance (median follow-up 3.05 years, IQR: 0.75-5.3 years); 19% (21/113) had an initial normal study and remained normal throughout follow-up; 19% (21/113) had an initial normal study with subsequent imaging reporting changes of CLD; and 62% (71/113) had existing changes of CLD on initial study. HCC was identified in 5 patients (median 22 years post-Fontan, IQR: 10-29 years), 4 of which had a normal initial study. Only 1 patient with HCC had concomitant viral hepatitis C infection. CONCLUSION: Radiologists should be aware that CLD is exceedingly common in post-Fontan cardiac physiology, and surveillance imaging is warranted given the risk of HCC.

Paraduodenal pancreatitis: benign and malignant mimics at MRI.

Paraduodenal pancreatitis, also known as groove pancreatitis, is a rare form of chronic pancreatitis that masquerades as pancreatic adenocarcinoma affecting the pancreaticoduodenal groove, a potential space between the head of the pancreas, duodenum, and common bile duct. Two forms of groove pancreatitis have been described. The segmental form involves the pancreatic head with development of scar tissue within the groove, whereas the pure form affects the groove only, sparing the pancreatic head. Imaging findings of groove pancreatitis often overlap with primary duodenal, ampullary, or pancreatic neoplasms, which often results in a diagnostic challenge. In addition, paraduodenal pancreatitis can be mistaken for cystic pancreatic lesions, especially when there is involvement of the duodenal wall. Preoperative recognition of this entity is very important in order to avoid unnecessary procedures, although surgery, such as pancreaticoduodenectomy, may still be required to relieve obstructive symptoms. In this article, the pathophysiology and magnetic resonance imaging characteristics of paraduodenal pancreatitis and important benign and malignant mimics are discussed.

Pericardial Effusion Following Hematopoietic Cell Transplantation in Children and Young Adults Is Associated with Increased Risk of Mortality.

Hematopoietic cell transplantation (HCT) is curative for many pediatric malignant and nonmalignant disorders but is associated with significant morbidity and mortality, including the development of pericardial effusion (PEF). We report the results of a retrospective chart review performed to assess the incidence, risk factors, and prognostic significance of PEF in pediatric HCT recipient at Lucile Packard Children's Hospital of Stanford University. A total of 119 patients undergoing HCT between January 2010 and December 2013 were selected through the hospital's Pediatric Stem Cell Transplant Program database. A retrospective chart review, including review of documentation, correspondence, imaging reports, laboratory values, and death records, was performed to collect data. The overall incidence of PEF in our population was 21%. Risk factors for the development of PEF included unrelated donor transplants and cord blood as the stem cell source (P = .005), whereas HLA mismatch approached significance (P = .05). The risk for development of PEF was found to not be significantly associated with acute or chronic graft-versus-host disease (GVHD), age at transplantation, sex, conditioning regimen, or viral reactivation status. Of interest, 6 of the 119 patients were found to have transplant-associated thrombotic microangiopathy (TA-TMA). Four of those 6 patients developed PEF, suggesting TA-TMA as a risk factor for PEF. Eight of the 25 patients who developed PEF (32%) required pericardiocentesis. Five out of the 8 patients requiring pericardiocentesis died owing to causes unrelated to the procedure or to PEF itself. Pericardial fluid testing in 4 of these patients (50%) was positive for human herpesvirus 6, Epstein-Barr virus, cytomegalovirus, and/or adenovirus. Finally, of significant interest, patients with PEF had a statistically significant higher likelihood of mortality compared with those without PEF (44% versus 17%; P = .007).

Extra-hepatic sarcoma metastasis surveillance in the liver: is arterial phase imaging necessary?

PURPOSE: To assess the value of arterial phase imaging (ART) in the detection of liver metastases on CT compared to portal venous phase imaging (PV) alone in patients with primary sarcomas. METHODS: Multiphasic abdominal computed tomography (CT) images of patients with tissue-proven sarcomas were reviewed by five abdominal radiologists in a staggered fashion. Up to three of the largest or most conspicuous liver lesions were characterized on a four-point confidence level for PV independently, followed by PV + ART. Inter-observer reliability was evaluated with kappa statistics. Change in characterization of lesions by the addition of ART was calculated. Follow-up imaging was used to determine if index lesion characterization was valid. RESULTS: 55 of 149 patients had 470 liver lesion characterizations by the five readers with follow-up. Inter-observer agreement was κ = 0.62 on PV and κ = 0.58 on PV + ART. The intra-observer agreement between PV and ART interpretations of the same lesion was κ = 0.93. 426 lesion characterizations were possible on both PV and ART. Only 6 characterizations were changed after the addition of ART; 4 of the 6 changes were incorrect when compared to follow-up. Only 6 lesion characterizations could be made on ART alone (missed by PV), with all the malignant lesions arising from primary leiomyosarcomas. For the lesions seen on PV alone, the sensitivity, specificity, PPV, NPV, and accuracy were 98.8%, 100%, 100%, 99.3%, and 99.6%, respectively. After the addition of ART, they were 98.8%, 98.7%, 97.5%, 99.4%, and 98.7%, respectively. CONCLUSION: ART adds marginal value to PV for characterization of metastatic liver lesions in patients with primary sarcomas, except possibly in primary leiomyosarcomas.

Comparative Effectiveness of Tumor Response Assessment Methods: Standard of Care Versus Computer-Assisted Response Evaluation.

PURPOSE: To compare the effectiveness of metastatic tumor response evaluation with computed tomography using computer-assisted versus manual methods. MATERIALS AND METHODS: In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, 11 readers from 10 different institutions independently categorized tumor response according to three different therapeutic response criteria by using paired baseline and initial post-therapy computed tomography studies from 20 randomly selected patients with metastatic renal cell carcinoma who were treated with sunitinib as part of a completed phase III multi-institutional study. Images were evaluated with a manual tumor response evaluation method (standard of care) and with computer-assisted response evaluation (CARE) that included stepwise guidance, interactive error identification and correction methods, automated tumor metric extraction, calculations, response categorization, and data and image archiving. A crossover design, patient randomization, and 2-week washout period were used to reduce recall bias. Comparative effectiveness metrics included error rate and mean patient evaluation time. RESULTS: The standard-of-care method, on average, was associated with one or more errors in 30.5% (6.1 of 20) of patients, whereas CARE had a 0.0% (0.0 of 20) error rate ( P < .001). The most common errors were related to data transfer and arithmetic calculation. In patients with errors, the median number of error types was 1 (range, 1 to 3). Mean patient evaluation time with CARE was twice as fast as the standard-of-care method (6.4 minutes v 13.1 minutes; P < .001). CONCLUSION: CARE reduced errors and time of evaluation, which indicated better overall effectiveness than manual tumor response evaluation methods that are the current standard of care.

Assessment of Added Value of Noncontrast to Contrast-Enhanced Abdominal Computed Tomography Scan for Characterization of Hypervascular Liver Metastases.

Assess the added value of nonenhanced computed tomography (NECT) to contrast-enhanced CT (CECT) of the abdomen for characterization of hypervascular liver metastases and incidental findings. Institutional review board approved, Health Insurance Probability and Accountability Act compliant, retrospective study of patients with melanoma, neuroendocrine tumor, or thyroid cancer. First available triphasic abdomen CT after initial diagnosis was reviewed by 3 radiologists. The 3 most suspicious lesions were characterized on the CECT as benign or malignant and then recharacterized after reviewing the NECT with CECT. Incidental renal and adrenal lesions were characterized similarly. Diagnostic performance of CECT vs its combination with NECT was assessed. Statistical significance level was set at P < 0.05. A total of 81 patients were included (mean age = 55 years; 52% male; 64% with liver lesions; 27% and 11% with incidental renal and adrenal lesions, respectively). Percentage area under the curve and 95% CI of CECT vs combination with NECT for characterization of liver metastases was 98(94-100) vs 99(96-100) for reviewer 1 (P = 0.35), 93(86-100) vs 94(87-100) for reviewer 2 (P = 0.23), and 96(90-100) vs 99(97-100) for reviewer 3 (P = 0.32). Mean difference in area under the curve and 95% CI between 2 protocols for characterization of liver, renal, and adrenal lesions were -0.007(-0.05 to 0.04) (P = 0.63), -0.09(-0.25 to 0.07) (P = 0.22), and -0.01(-0.05 to 0.02) (P = 0.27), respectively. After addition of NECT, confidence level for lesion characterization increased 4%-15% for liver metastases, 18%-59% and 33%-67% for renal and adrenal lesions, respectively. In conclusion, while addition of NECT to CECT improved radiologist' confidence, there was no statistically significant change in characterization of hypervascular liver metastases or incidental renal and adrenal lesions.

Intubation Performance of Advanced Airway Devices in a Helicopter Emergency Medical Service Setting.

OBJECTIVE: This study attempts to determine if newer indirect laryngoscopes or intubating devices are superior to a standard laryngoscope for intubation success among helicopter emergency medical service (HEMS) personnel. METHODS: Flight nurses and paramedics intubated standardized mannequins with a normal airway, a trauma airway, and a difficult airway using a standard laryngoscope, a gum elastic bougie, the Airtraq laryngoscope (King System Corp, Noblesville, IN), the Glidescope Ranger laryngoscope (Verathon Inc, Bothell, WA), and the S.A.L.T. device (Microtek Medical, Inc, Lehmberg, IN) in grounded helicopters wearing helmets and flight gear. Participant demographics, time to glottic view, the modified Cormack-Lehane score, total intubation time, number of attempts, and overall successful intubation were recorded for each type of airway. RESULTS: Two-hundred thirty-six subjects were initially enrolled across 107 bases in 15 states, and 177 completed the study. First-attempt success rates did not vary by device for the normal airway (P = .203), but the Airtraq laryngoscope and the S.A.L.T. device were highest in the difficult airway (82.0% and 85.0%, respectively; P < .0001). The time to first-attempt success in the difficult airway was lowest for the S.A.L.T. device and the Airtraq laryngoscope (mean = 9.72 seconds and 19.70 seconds, respectively; P < .0001). CONCLUSION: Using HEMS providers, the Airtraq laryngoscope and the S.A.L.T. device showed the fastest and highest intubation success on the first attempt in difficult simulated HEMS airway scenarios.

Beyond complications: Comparison of procedural differences and diagnostic success between nurse practitioners and radiologists performing image-guided renal biopsies.

PURPOSE: Radiology-trained nurse practitioners (NPs) may perform image-guided medical renal biopsies with computed tomography (CT). This study evaluates the procedural differences and diagnostic success between biopsies performed by NPs compared to radiologists. DATA SOURCES: A retrospective study was performed on patients who underwent nontargeted, CT-guided renal biopsy between 2009 and 2014. Provider type (NP or radiologist), number of core specimens obtained, sedation medication dose, CT dose index (CTDI), and diagnostic success were recorded. Categorical and continuous variables were analyzed using χ2 and Student's two-tailed t-test, respectively, comparing NPs with radiologists. CONCLUSIONS: A total of 386 patients were included; radiologists performed 215 biopsies and NPs performed 171 biopsies. There was no significant difference in diagnostic success, amount of tissue harvested (number of cores), radiation dose, or sedation dosage between NPs and radiologists performing CT-guided renal biopsies. Only 4% were nondiagnostic (n = 7, radiologists; n = 9, NPs; p = .325). Overall mean number of cores obtained was 3.7, mean CTDI was 176.5 mGy, mean fentanyl dose was 86.3 µg, and mean midazolam was dose 1.54 mg without a statistically significant difference between provider types. IMPLICATIONS FOR PRACTICE: NPs perform image-guided medical renal biopsies in a similar fashion to radiologists with respect to diagnostic success, amount of tissue harvested, total radiation dose exposure, and administration of sedation.

Reassessing medicare trends in diagnostic CT colonography after achieving CPT code category I status.

PURPOSE: Compare national trends in utilization and coverage of diagnostic (non-screening) computed tomography colonography (CTC) in the Medicare population before and after achieving Current Procedural Terminology(®) (CPT) Category I code status in 2010. METHODS: Claims by provider type and location for diagnostic CTC were identified between 2005 and 2013 using Medicare Physician Supplier Procedure Summary Master Files. Frequencies of billed and denied services were used to calculate denial rates for CTC and abdominal computed tomography (CT). PubMed search for articles with "CT colonography" in abstract or title during 1997-2013 was performed. Publications were recorded yearly and matched to CTC denial rates. RESULTS: Annual Medicare claims for diagnostic CTC increased 212% during 2005-2009 in Category III status and increased 27.4% during 2009-2013 after implementation of Category I codes. Claims for abdominal CT rose 13.4% over the same overall period. Denial rates decreased from 70% to 32.8% between 2005 and 2009, and fluctuated between 24.7 and 30.6% thereafter. Denial rates for abdominal CT remained constant (4.1%-4.6%). From 2005 to 2013, services grew most in the private office (1678-7293) and hospital outpatient (1644-6449) settings with radiologists performing 93.3% of CTC. 1037 CTC publications were identified which increased 3567% between 1997 (3) and 2008 (107), plateaued until 2010 (114) and declined thereafter (75 in 2013). CONCLUSIONS: Diagnostic CTC grew dramatically from 2005 to 2009, but slowed thereafter; even after achieving CPT Category I code status in 2010. Medicare denial rates declined during early years but later stabilized which paralleled a slowing in new peer-reviewed research. CTC continues to be performed predominately by radiologists in the outpatient setting.