Lugano 2014 criteria for assessing FDG-PET/CT in lymphoma: an operational approach for clinical trials.

An operationalized workflow paradigm is presented and validated with pilot subject data. This approach is reproducible with a high concordance rate between individual readers (kappa 0.73 [confidence interval 0.59-0.87; P=<0.0001]) using a 5-point scale to assess [18F] labeled fluorodeoxyglucose metabolic activity in lymphomatous lesions. These results suggest an operationally practical 5-point scale workflow paradigm for potential use in larger clinical trials evaluating lymphoma therapeutics.

Diagnostic Performance of the Visual Reading of 123I-Ioflupane SPECT Images With or Without Quantification in Patients With Movement Disorders or Dementia.

Visual interpretation of 123I-ioflupane SPECT images has high diagnostic accuracy for differentiating parkinsonian syndromes (PS), from essential tremor and probable dementia with Lewy bodies (DLB) from Alzheimer disease. In this study, we investigated the impact on accuracy and reader confidence offered by the addition of image quantification in comparison with visual interpretation alone. Methods: We collected 304 123I-ioflupane images from 3 trials that included subjects with a clinical diagnosis of PS, non-PS (mainly essential tremor), probable DLB, and non-DLB (mainly Alzheimer disease). Images were reconstructed with standardized parameters before striatal binding ratios were quantified against a normal database. Images were assessed by 5 nuclear medicine physicians who had limited prior experience with 123I-ioflupane interpretation. In 2 readings at least 1 mo apart, readers performed either a visual interpretation alone or a combined reading (i.e., visual plus quantitative data were available). Readers were asked to rate their confidence of image interpretation and judge scans as easy or difficult to read. Diagnostic accuracy was assessed by comparing image results with the standard of truth (i.e., diagnosis at follow-up) by measuring the positive percentage of agreement (equivalent to sensitivity) and the negative percentage of agreement (equivalent to specificity). The hypothesis that the results of the combined reading were not inferior to the results of the visual reading analysis was tested. Results: A comparison of the combined reading and the visual reading revealed a small, insignificant increase in the mean negative percentage of agreement (89.9% vs. 87.9%) and equivalent positive percentages of agreement (80.2% vs. 80.1%). Readers who initially performed a combined analysis had significantly greater accuracy (85.8% vs. 79.2%; P = 0.018), and their accuracy was close to that of the expert readers in the original studies (range, 83.3%-87.2%). Mean reader confidence in the interpretation of images showed a significant improvement when combined analysis was used (P < 0.0001). Conclusion: The addition of quantification allowed readers with limited experience in the interpretation of 123I-ioflupane SPECT scans to have diagnostic accuracy equivalent to that of the experienced readers in the initial studies. Also, the results of the combined reading were not inferior to the results of the visual reading analysis and offered an increase in reader confidence.

Supervised learning technique for the automated identification of white matter hyperintensities in traumatic brain injury.

BACKGROUND: White matter hyperintensities (WMHs) are foci of abnormal signal intensity in white matter regions seen with magnetic resonance imaging (MRI). WMHs are associated with normal ageing and have shown prognostic value in neurological conditions such as traumatic brain injury (TBI). The impracticality of manually quantifying these lesions limits their clinical utility and motivates the utilization of machine learning techniques for automated segmentation workflows. METHODS: This study develops a concatenated random forest framework with image features for segmenting WMHs in a TBI cohort. The framework is built upon the Advanced Normalization Tools (ANTs) and ANTsR toolkits. MR (3D FLAIR, T2- and T1-weighted) images from 24 service members and veterans scanned in the Chronic Effects of Neurotrauma Consortium's (CENC) observational study were acquired. Manual annotations were employed for both training and evaluation using a leave-one-out strategy. Performance measures include sensitivity, positive predictive value, [Formula: see text] score and relative volume difference. RESULTS: Final average results were: sensitivity = 0.68 ± 0.38, positive predictive value = 0.51 ± 0.40, [Formula: see text] = 0.52 ± 0.36, relative volume difference = 43 ± 26%. In addition, three lesion size ranges are selected to illustrate the variation in performance with lesion size. CONCLUSION: Paired with correlative outcome data, supervised learning methods may allow for identification of imaging features predictive of diagnosis and prognosis in individual TBI patients.

Disruption of caudate working memory activation in chronic blast-related traumatic brain injury.

Mild to moderate traumatic brain injury (TBI) due to blast exposure is frequently diagnosed in veterans returning from the wars in Iraq and Afghanistan. However, it is unclear whether neural damage resulting from blast TBI differs from that found in TBI due to blunt-force trauma (e.g., falls and motor vehicle crashes). Little is also known about the effects of blast TBI on neural networks, particularly over the long term. Because impairment in working memory has been linked to blunt-force TBI, the present functional magnetic resonance imaging (fMRI) study sought to investigate whether brain activation in response to a working memory task would discriminate blunt-force from blast TBI. Twenty-five veterans (mean age = 29.8 years, standard deviation = 6.01 years, 1 female) who incurred TBI due to blast an average of 4.2 years prior to enrollment and 25 civilians (mean age = 27.4 years, standard deviation = 6.68 years, 4 females) with TBI due to blunt-force trauma performed the Sternberg Item Recognition Task while undergoing fMRI. The task involved encoding 1, 3, or 5 items in working memory. A group of 25 veterans (mean age = 29.9 years, standard deviation = 5.53 years, 0 females) and a group of 25 civilians (mean age = 27.3 years, standard deviation = 5.81 years, 0 females) without history of TBI underwent identical imaging procedures and served as controls. Results indicated that the civilian TBI group and both control groups demonstrated a monotonic relationship between working memory set size and activation in the right caudate during encoding, whereas the blast TBI group did not (p < 0.05, corrected for multiple comparisons using False Discovery Rate). Blast TBI was also associated with worse performance on the Sternberg Item Recognition Task relative to the other groups, although no other group differences were found on neuropsychological measures of episodic memory, inhibition, and general processing speed. These results could not be attributed to caudate atrophy or the presence of PTSD symptoms. Our results point to a specific vulnerability of the caudate to blast injury. Changes in activation during the Sternberg Item Recognition Task, and potentially other tasks that recruit the caudate, may serve as biomarkers for blast TBI.

RADPEER peer review: relevance, use, concerns, challenges, and direction forward.

RADPEER is a product developed by the ACR that aims to assist radiologists with quality assessment and improvement through peer review. The program opened in 2002, was initially offered to physician groups in 2003, developed an electronic version in 2005 (eRADPEER), revised the scoring system in 2009, and first surveyed the RADPEER membership in 2010. In 2012, a survey was sent to 16,000 ACR member radiologists, both users and nonusers of RADPEER, with the goal of understanding how to make RADPEER more relevant to its members. A total of 31 questions were used, some of which were repeated from the 2010 survey. The ACR's RADPEER committee has published 3 papers on the program since its inception. In this report, the authors summarize the survey results and suggest future opportunities for making RADPEER more useful to its membership.

Correlation of findings from iodine 123 scan and ultrasonography in the recommendation for thyroid fine-needle aspiration biopsy.

OBJECTIVE: To assess the impact of correlating findings from iodine I 123 (¹²³I) radionuclide scans and thyroid ultrasonography on the decision to perform fine-needle aspiration (FNA) biopsy of thyroid nodules. METHODS: Iodine 123 scans and sonographic images of adult patients who had both examinations performed within 6 months of each other at our institution were retrospectively reviewed. The presence of 1 or more nodules satisfying imaging-specific criteria for recommending FNA biopsy was recorded. Iodine 123 scan and sonographic images were then directly compared to determine how frequently the FNA recommendation would be affected by discordant findings. RESULTS: The study included 97 adult patients, with a total of 291 thyroid lobes (right thyroid lobe, left thyroid lobe, and isthmus). Recommendations for FNA biopsy were concordant in 231 of 291 lobes (79.4%), with both modalities recommending FNA biopsy in 55 lobes and not recommending FNA biopsy in 176 lobes. A discordant recommendation occurred in 60 of 291 lobes (20.6%). Using only ultrasonography findings, a recommendation for FNA biopsy was not indicated for 11 of the 291 lobes (3.8%) with functioning nodules. Using only ¹²³I findings, a recommendation for FNA biopsy was not indicated for 23 of the 291 lobes (7.9%); 13 had nodules, but none that fulfilled sonographic criteria, and 10 had no identifiable nodule on ultrasonography. Iodine 123 scan did not identify 26 lobes with nodules (8.9%) for which FNA biopsy was recommended based on ultrasonography findings. CONCLUSION: Recommendations for FNA biopsy should not be based on the presence of hypofunctioning regions on ¹²³I scan without sonographic confirmation.

Inpatient CT and MRI utilization: trends in the academic hospital setting.

PURPOSE: The aim of this study was to determine trends in the utilization of inpatient CT and MRI at academic medical centers. METHODS: Surveys requesting inpatient CT volumes, inpatient MRI volumes, discharges excluding newborns, and case-adjusted mix index from 2002 to 2007 were e-mailed to all 123 members of the Society of Chairmen of Academic Radiology Departments. CT and MRI studies per discharge were adjusted using the case mix index (CMI) provided by each hospital to adjust for the differences in patient mix at participating institutions. Trends in adjusted inpatient imaging utilization were compared over time and across responding institutions. RESULTS: Twenty-two of 123 chairs (17.9%) of academic radiology departments, representing all geographic regions and a wide variability in National Institutes of Health research funding ranking, provided responses to our survey. Between 2002 and 2007, there was an increase in median CMI-adjusted CT studies per discharge of 28.0% and an increase in median CMI-adjusted MRI studies per discharge of 19.8%. The largest annual percentage increase in CT utilization (20.2%) occurred from 2003 to 2004, and there was negative growth between 2006 and 2007 of -3.74%. The largest annual percentage increase in MRI utilization (13.9%) occurred from 2006 to 2007, with 3 years of negative growth from 2002 to 2003, 2004 to 2005, and 2005 to 2006. In 2007, there was a wide range in CMI-adjusted CT studies per discharge between institutions from 0.16 to 0.75, with a mean of 0.40 ± 0.18, with a corresponding wide range in CMI-adjusted MRI studies per discharge of 0.04 to 0.16, with a mean of 0.09 ± 0.03. CONCLUSION: There has been large growth in inpatient CT and MRI utilization at academic medical centers. This growth is variable over time and between institutions. Practice leaders can use this information to compare themselves with their peers and to monitor the impact of programmatic improvements on inpatient imaging utilization and in discussions with health system leaders who would like to improve system profitability by decreasing costly inpatient imaging procedures.

Trends in PET scanner ownership and leasing by nonradiologist physicians.

PURPOSE: The aim of this study was to examine growth trends in ownership or leasing of private-office PET scanners by nonradiologist physicians. MATERIALS AND METHODS: The Medicare Part B Physician/Supplier Procedure Summary Master Files for 2002 through 2007 were used to collect the following data for each PET-related Current Procedural Terminology((R)) code: 1) annual procedure volume, 2) places of service for the procedures, and 3) specialties of the physicians filing the claims. To determine ownership or leasing, only technical and global claims that occurred in the nonhospital, private-office setting were included in the study. Professional component-only claims were not included. Procedure volume and growth trends were compared between radiologists and other specialties. RESULTS: Between 2002 and 2007, radiologist-owned Medicare PET scans increased by 259%, whereas nonradiologist-owned or nonradiologist-leased scans grew by 737%. Five specialty groups accounted for 95% of all nonradiologist PET volume in 2007: internal medicine subspecialties (28,324 studies in 2007), medical oncology (14,320 studies), cardiology (13,724 studies), radiation oncology (9,563 studies), and primary care (2,398 studies). In 2002, of all Medicare PET examinations performed on units owned or leased by physicians, the share for nonradiologists was 13%; their share rose to 24% in 2007. CONCLUSION: Although a large percentage of PET scans in private offices are done by radiologists, the growth rate among nonradiologists was far higher between 2002 and 2007 (259% for the former, 737% for the latter). The disproportionately rapid growth of PET scans performed on units owned by nonradiologists raises concern about self-referral at a time when policymakers are struggling to contain costs and reduce radiation exposure.

Role models in academic radiology: current status and pathways to improvement.

PURPOSE: The aim of this study was to determine residents' attitudes about the influence and characteristics of academic radiology role models. METHOD: A Web-based survey was sent to the 35 residents in the 2007 Siemens AUR Radiology Resident Academic Development (SARRAD) program and to all other residents at their institutions. The survey contained questions regarding experiences with and desirable characteristics of role models, as well as the influence of role models in career decisions. Chi-square, Fisher's exact, and Mann-Whitney tests were used to assess associations between responses and expressed career choice. RESULTS: Thirty of 35 SARRAD participants (85%) plus 103 non-SARRAD participants responded. Only 46% felt that there were enough role models at their institutions and 56% that there were sufficient role models in academic radiology. More than two-thirds of residents surveyed stated that they would be more likely to stay in academic radiology if there were more role models. The most desired characteristics of role models included availability, enthusiasm, integrity, and a positive attitude toward residents. Residents stating that they would choose academic careers were more likely to be research track (P = .0001), have more publications (P = .01), be less concerned with salary (P = .003), and be less concerned about politics (P = .047). Level of debt was not different between residents planning to choose academic careers and those with other career plans (P = .80). CONCLUSION: Role models in academic radiology play an important role in influencing residents to stay in academic radiology. Increasing the number of role models in academic radiology with characteristics valued by residents will encourage residents to stay in academic medicine.

Testing low-risk patients for suspected pulmonary embolism: a decision analysis.

STUDY OBJECTIVE: The Pulmonary Embolism Rule-out Criteria (PERC) identifies low-risk patients who are treated in the emergency department for suspected pulmonary embolism and for whom testing may be deferred. The purpose of this study is to develop a decision model to determine whether certain elements not included in the PERC methodology could better estimate the testing threshold for pulmonary embolism (ie, the pretest probability below which a patient should not be tested for pulmonary embolism). In addition, we determine which risks and benefits of pulmonary embolism evaluation and treatment have the greatest effect on the testing threshold. METHODS: We built decision models of low-risk patients with suspected pulmonary embolism, as determined by the PERC. We obtained model inputs from the literature or by using clinical judgment when data were unavailable. One-way sensitivity analysis derived the testing threshold, and 2-way sensitivity analysis was used to determine the main drivers of the testing threshold. RESULTS: We found an average testing threshold of 1.4% across all age and sex cohorts. Two-way sensitivity analysis demonstrated that risk of major bleeding from anticoagulation, mortality from contrast-induced renal failure, risk of cancer from computed tomography scan, and mortality from both treated and untreated pulmonary embolism had the greatest effects on the testing threshold. CONCLUSION: We found a testing threshold for the PERC similar to that calculated by the Pauker and Kassirer method, using somewhat different assumptions. The 5 major drivers for the testing threshold are variables for which there is a paucity of literature to assess accurately for low-risk patients.

Comparison of two methods to transmit clinical history information from referring providers to radiologists.

PURPOSE: At many institutions, clerical personnel manually enter clinical histories into radiology information systems during the process of scheduling examinations. For outpatients, radiologists use this information as their primary source of clinical histories. The purpose of this study was to determine the discrepancy rate between these manually recorded clinical histories and paper request slips, thereby assessing the accuracy of the clinical information used by radiologists at the time of interpretation. MATERIALS AND METHODS: A total of 129 imaging request slips for CT scans were randomly selected from 7 days in February and March 2007. The clinical history on each request slip was compared with the clinical history manually entered into the radiology information system. Discrepancies between paper request slips and the electronic information available to radiologists were placed into 4 categories: 1) no discrepancy, 2) electronic or paper history incomplete, 3) disagreement between electronic and paper information, and 4) other. Incomplete or discrepant histories were further subcategorized on the basis of whether they were clinically significant. RESULTS: Thirty-eight percent of studies (49 of 129) had no discrepancies between the paper request slips and the manually entered electronic information. The remaining 62% of studies (80 of 129) had incomplete or discrepant clinical histories. Forty-nine percent of studies (63 of 129) had incomplete electronic or paper information. Greater than half of those incomplete histories (36 of 63) were clinically significant. Ten percent of cases (13 of 129) showed frank disagreements between paper and electronic information. Sixty-nine percent of these (9 of 13) were clinically significant. Three percent of studies (4 of 129) showed other discrepancies whose clinical significance could not be categorized. CONCLUSION: The manual entry of clinical information introduces a high rate of discrepancies, most of which are clinically significant. These discrepancies highlight the need for better communication between referring providers and radiologists.

Neuro-lyme disease: MR imaging findings.

PURPOSE: To describe the neuroimaging manifestations of Lyme disease at magnetic resonance (MR) imaging of the brain. MATERIALS AND METHODS: Institutional review board approval was obtained and HIPAA compliance was followed. This study retrospectively reviewed the MR imaging findings of all patients seen from 1993 to 2007 in whom neuro-Lyme disease was suspected and who were referred for MR imaging of the brain for the evaluation of neurologic symptoms. RESULTS: Of 392 patients suspected of having neuro-Lyme disease, 66 patients proved to have the disease on the basis of clinical criteria, serologic results, and response to treatment. Seven of these 66 patients showed foci of T2 prolongation in the cerebral white matter, one had an enhancing lesion with edema, and three demonstrated nerve-root or meningeal enhancement. Of the seven patients with foci of T2 prolongation in the white matter, three were an age at which white matter findings due to small-vessel disease are common. CONCLUSION: In cases of nerve-root or meningeal enhancement, Lyme disease should be considered in the differential diagnosis in the proper clinical setting.

The effect of initial shunt outflow position on patency of transjugular intrahepatic portosystemic shunts.

PURPOSE: It has been suggested that initial stent position in transjugular intrahepatic portosystemic shunts (TIPS) with relation to hepatic venous outflow is an important determinant of shunt patency. It was hypothesized that TIPS with the stent-implanted segments terminating in the hepatic vein (HV) have shorter primary unassisted shunt patency durations than TIPS with the stent-implanted segments extending to the hepatocaval junction. MATERIALS AND METHODS: A consecutive group of 107 patients who underwent TIPS creation for variceal bleeding were retrospectively identified, and the angiographic images during initial TIPS creation were reviewed independently by two observers who were blinded to outcome. Primary unassisted patency was estimated in group A (TIPS terminating in the HV; n = 47) and group B (TIPS terminating at the hepatocaval junction; n = 60) with the Kaplan-Meier method, and the two groups were compared with the log-rank test. Patients who had less than 30 days of follow-up were excluded from the analysis. RESULTS: Among all 107 patients, primary unassisted patency rates at 3, 6, and 12 months were 91% +/- 4%, 74% +/- 6%, and 49% +/- 6%. TIPS were classified into group A or group B with high interobserver agreement (Cohen kappa = 0.98). At 12 months, the primary unassisted patency rate among the patients in group A was 36% +/- 10%, compared with 58% +/- 8% among the patients in group B (P =.017, log-rank test). Patients in group A were twice as likely to lose patency than patients in group B (95% CI of odds ratio, 1.2-4.5). Thirty-day mortality was similar between groups (15% vs 12%; P =.13). CONCLUSION: Initial stent position within the hepatic venous outflow is predictive of shunt patency, with TIPS extending to the hepatocaval junction having a longer lifespan than shunts terminating in the HV.