Deep learning for classification of thyroid nodules on ultrasound: validation on an independent dataset.

OBJECTIVES: The purpose is to apply a previously validated deep learning algorithm to a new thyroid nodule ultrasound image dataset and compare its performances with radiologists. METHODS: Prior study presented an algorithm which is able to detect thyroid nodules and then make malignancy classifications with two ultrasound images. A multi-task deep convolutional neural network was trained from 1278 nodules and originally tested with 99 separate nodules. The results were comparable with that of radiologists. The algorithm was further tested with 378 nodules imaged with ultrasound machines from different manufacturers and product types than the training cases. Four experienced radiologists were requested to evaluate the nodules for comparison with deep learning. RESULTS: The Area Under Curve (AUC) of the deep learning algorithm and four radiologists were calculated with parametric, binormal estimation. For the deep learning algorithm, the AUC was 0.69 (95% CI: 0.64-0.75). The AUC of radiologists were 0.63 (95% CI: 0.59-0.67), 0.66 (95% CI:0.61-0.71), 0.65 (95% CI: 0.60-0.70), and 0.63 (95%CI: 0.58-0.67). CONCLUSION: In the new testing dataset, the deep learning algorithm achieved similar performances with all four radiologists. The relative performance difference between the algorithm and the radiologists is not significantly affected by the difference of ultrasound scanner.

LI-RADS Treatment Response Algorithm: Performance and Diagnostic Accuracy.

Background In 2017, the Liver Imaging Reporting and Data System (LI-RADS) included an algorithm for the assessment of hepatocellular carcinoma (HCC) treated with local-regional therapy. The aim of the algorithm was to enable standardized evaluation of treatment response to guide subsequent therapy. However, the performance of the algorithm has not yet been validated in the literature. Purpose To evaluate the performance of the LI-RADS 2017 Treatment Response algorithm for assessing the histopathologic viability of HCC treated with bland arterial embolization. Materials and Methods This retrospective study included patients who underwent bland arterial embolization for HCC between 2006 and 2016 and subsequent liver transplantation. Three radiologists independently assessed all treated lesions by using the CT/MRI LI-RADS 2017 Treatment Response algorithm. Radiology and posttransplant histopathology reports were then compared. Lesions were categorized on the basis of explant pathologic findings as either completely (100%) or incompletely (<100%) necrotic, and performance characteristics and predictive values for the LI-RADS Treatment Response (LR-TR) Viable and Nonviable categories were calculated for each reader. Interreader association was calculated by using the Fleiss κ. Results A total of 45 adults (mean age, 57.1 years ± 8.2; 13 women) with 63 total lesions were included. For predicting incomplete histopathologic tumor necrosis, the accuracy of the LR-TR Viable category for the three readers was 60%-65%, and the positive predictive value was 86%-96%. For predicting complete histopathologic tumor necrosis, the accuracy of the LR-TR Nonviable category was 67%-71%, and the negative predictive value was 81%-87%. By consensus, 17 (27%) of 63 lesions were categorized as LR-TR Equivocal, and 12 of these lesions were incompletely necrotic. Interreader association for the LR-TR category was moderate (κ = 0.55; 95% confidence interval: 0.47, 0.67). Conclusion The Liver Imaging Reporting and Data System 2017 Treatment Response algorithm had high predictive value and moderate interreader association for the histopathologic viability of hepatocellular carcinoma treated with bland arterial embolization when lesions were assessed as Viable or Nonviable. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Gervais in this issue.

Imaging-guided percutaneous thrombin injection for the treatment of iatrogenic femoral artery pseudoaneurysms.

PURPOSE: To evaluate factors that may affect successful ultrasound-guided percutaneous thrombin injection of iatrogenic femoral artery pseudoaneurysms (PSA). MATERIALS AND METHODS: This was an IRB-approved, HIPAA-compliant retrospective study of 326 consecutive subjects (138 males, 188 females; mean age 68 years, range 18-95) who underwent thrombin injection for treatment of femoral PSA; follow-up ultrasound was available in 145 subjects. The number of PSA lobes and dimensions, pre-procedure laboratory values (international normalized ratio [INR], activated partial thromboplastin time [aPTT], platelet count), and concomitant anticoagulation therapy were recorded. RESULTS: Technical success was achieved in 98.2% (320/326) of subjects. Primary effectiveness (complete thrombosis at 24 h) was achieved in 74.5% (108/145). Twenty-five subjects underwent repeat thrombin injection, successful in 21 subjects, for a total effectiveness rate of 97.0% (129/133). No imaging factor was associated with technique failure, including number of lobes (p = 0.898), largest dimension (p = 0.344), or volume (p = 0.697). No statistically significant difference in pre-procedure INR, aPTT, or platelet count was found between subjects with CT and those with IT (p > 0.138). Anticoagulation therapy was associated with incomplete thrombosis (35.5% [38/107] for CT vs. 63.9% [23/26] for IT; p = 0.002). CONCLUSION: Imaging-guided percutaneous thrombin injection has high technical success and effectiveness rates for the treatment of iatrogenic femoral artery PSA. Anticoagulation therapy was the only factor associated with incomplete thrombosis.

Repeat CT Performed Within One Month of CT Conducted in the Emergency Department for Abdominal Pain: A Secondary Analysis of Data From a Prospective Multicenter Study.

OBJECTIVE: The purpose of this study is to determine both the frequency of repeat CT performed within 1 month after a patient visits the emergency department (ED) and undergoes CT evaluation for abdominal pain and the frequency of worsened or new CT-based diagnoses. SUBJECTS AND METHODS: Secondary analysis was performed on data collected during a prospective multicenter study. The parent study included patients who underwent CT in the ED for abdominal pain between 2012 and 2014, and these patients constituted the study group of the present analysis. The proportion of patients who underwent (in any setting) repeat abdominal CT within 1 month of the index CT examination was calculated. For each of these patients, results of the index and repeat CT scans were compared by an independent panel and categorized as follows: no change (group 1); same process, improved (group 2); same process, worse (group 3); or different process (group 4). The proportion of patients in groups 1 and 2 versus groups 3 and 4 was calculated, and patient and ED physician characteristics were compared. RESULTS: The parent study included 544 patients (246 of whom were men [45%]; mean patient age, 49.4 years). Of those 544 patients, 53 (10%; 95% CI, 7.5-13%) underwent repeat abdominal CT. Patients' CT comparisons were categorized as follows: group 1 for 43% of patients (23/53), group 2 for 26% (14/53), group 3 for 15% (8/53), and group 4 for 15% (8/53). New or worse findings were present in 30% of patients (16/53) (95% CI, 19-44%). When patients with findings in groups 1 and 2 were compared to patients with findings in groups 3 and 4, no significant difference was noted in patient age (p = 0.25) or sex (p = 0.76), the number of days between scans (p = 0.98), and the diagnostic confidence of the ED physician after the index CT scan was obtained (p = 0.33). CONCLUSION: Short-term, repeat abdominal CT was performed for 10% of patients who underwent CT in the ED for abdominal pain, and it yielded new or worse findings for 30% of those patients.

Comparison of Visualization Rates of LI-RADS Version 2014 Major Features With IV Gadobenate Dimeglumine or Gadoxetate Disodium in Patients at Risk for Hepatocellular Carcinoma.

OBJECTIVE: The purpose of this study is to compare visualization rates of the major features covered by Liver Imaging Reporting and Data System (LI-RADS) version 2014 in patients at risk for hepatocellular carcinoma using either gadobenate dimeglumine or gadoxetate disodium IV contrast agent. MATERIALS AND METHODS: This retrospective study included liver MRI examinations performed with either gadobenate dimeglumine or gadoxetate disodium contrast enhancement. Using age, sex, underlying liver disease, and presence of cirrhosis, patients were placed into matched cohorts. All hepatic nodules 1 cm or larger (up to five per subject) were included, resulting in 63 subjects with 130 nodules (median nodule size, 1.9 cm) imaged with gadobenate and 64 subjects with 117 nodules (median nodule size, 2.0 cm) imaged with gadoxetate. Three radiologists reviewed the studies for LI-RADS major features independently. Bootstrap resampling with 10,000 repetitions was used to compare feature detection rates. RESULTS: Arterial phase hyperenhancement was seen in a similar number of nodules with gadobenate dimeglumine (mean, 91.5% [119/130]) and gadoxetate disodium (mean, 88.0% [103/117]) (p = 0.173). Dynamic phase washout was more commonly seen with gadobenate dimeglumine (mean, 60.2% [78.3/130]) than with gadoxetate disodium (mean, 45.3% [53/117]) (p = 0.006). The capsule feature was more often visualized with gadobenate dimeglumine (mean, 50.2% [65.3/130]) than with gadoxetate disodium (mean, 33.3% [39/117]) (p < 0.001). Interreader agreement for arterial phase enhancement and dynamic phase washout was almost perfect for both contrast agents (κ > 0.83). Agreement for the capsule feature was moderate for gadobenate dimeglumine (κ = 0.52) and substantial for gadoxetate disodium (κ = 0.67). CONCLUSION: The rates of visualization of arterial phase hyperenhancement are similar in studies performed with gadobenate dimeglumine and gadoxetate disodium, but dynamic phase washout and capsule appearance are more commonly visualized with gadobenate dimeglumine.

Emergency Neurological Life Support: Third Edition, Updates in the Approach to Early Management of a Neurological Emergency.

Emergency Neurologic Life Support (ENLS) is an educational program designed to provide users advisory instructions regarding management for the first few hours of a neurologic emergency. The content of the course is divided into 14 modules, each addressing a distinct category of neurological injury. The course is appropriate for practitioners and providers from various backgrounds who work in environments of variable medical complexity. The focus of ENLS is centered on a standardized treatment algorithm, checklists, to guide early patient care, and a structured format for communication of findings and concerns to other healthcare professionals. Certification and training in ENLS is hosted by the Neurocritical Care Society. This document introduces the concept of ENLS and describes revisions that constitute the third version.

Role of CT in the Diagnosis of Nonspecific Abdominal Pain: A Multicenter Analysis.

OBJECTIVE: The objective of our study was to determine whether specific patient and physician factors-known before CT-are associated with a diagnosis of nonspecific abdominal pain (NSAP) after CT in the emergency department (ED). MATERIALS AND METHODS: We analyzed data originally collected in a prospective multicenter study. In the parent study, we identified ED patients referred to CT for evaluation of abdominal pain. We surveyed their physicians before and after CT to identify changes in leading diagnoses, diagnostic confidence, and admission decisions. In the current study, we conducted a multiple regression analysis to identify whether the following were associated with a post-CT diagnosis of NSAP: patient age; patient sex; physicians' years of experience; physicians' pre-CT diagnostic confidence; and physicians' pre-CT admission decision if CT had not been available. We analyzed patients with and those without a pre-CT diagnosis of NSAP separately. For the sensitivity analysis, we excluded patients with different physicians before and after CT. RESULTS: In total, 544 patients were included: 10% (52/544) with a pre-CT diagnosis of NSAP and 90% (492/544) with a pre-CT diagnosis other than NSAP. The leading diagnoses changed after CT in a large proportion of patients with a pre-CT diagnosis of NSAP (38%, 20/52). In regression analysis, we found that physicians' pre-CT diagnostic confidence was inversely associated with a post-CT diagnosis of NSAP in patients with a pre-CT diagnosis other than NSAP (p = 0.0001). No other associations were significant in both primary and sensitivity analyses. CONCLUSION: With the exception of physicians' pre-CT diagnostic confidence, the factors evaluated were not associated with a post-CT diagnosis of NSAP.

Structured Reporting of Magnetic Resonance Enterography for Pediatric Crohn's Disease: Effect on Key Feature Reporting and Subjective Assessment of Disease by Referring Physicians.

PURPOSE: To objectively compare the content of structured reports (SR) vs nonstructured reports (NSR) for magnetic resonance enterography (MRE) of pediatric patients with Crohn's disease, and to evaluate referring clinicians' subjective assessment of reports. METHODS: This institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study included 25 pediatric subjects (15 male, 10 female; mean age = 14 years [range: 9-18 years]) with Crohn's disease imaged with MRE. Three radiologists independently interpreted all examinations using both NSR and SR, separated by 4 weeks. Reports were assessed for documentation of the presence or absence of 15 key reporting features. A total of 30 reports (15 NSR [5 per reader] and 15 SR [5 per reader]) were randomly selected for review by 3 referring physicians, who subjectively evaluated the reports independently. RESULTS: NSR documented the presence or absence of 7.7 ± 2.5 key features, whereas SR documented 14.0 ± 0.8 features (P < 0.001). SR resulted in increased documentation of 12 of 15 features including stricture (P < 0.001), fistula (P < 0.001), fluid collection (P = 0.003), and perianal disease (P < 0.001). Referring physicians preferred SR regarding ease of information extraction, clarity of anatomy, and ability to identify disease phenotype (P < 0.01 for each). CONCLUSION: The use of structured reporting in describing pediatric Crohn's disease, MRE resulted in significantly increased reporting of key features. Referring clinicians also demonstrated a subjective preference for SR.

Intravenous Gadoxetate Disodium Administration Reduces Breath-holding Capacity in the Hepatic Arterial Phase: A Multi-Center Randomized Placebo-controlled Trial.

Purpose To determine, in a multicenter double-blinded placebo-controlled trial, whether maximal hepatic arterial phase breath-holding duration is affected by gadoxetate disodium administration. Materials and Methods Institutional review board approval was obtained for this prospective multi-institutional HIPAA-compliant study; written informed consent was obtained from all subjects. At three sites, a total of 44 volunteers underwent a magnetic resonance (MR) imaging examination in which images were acquired before and dynamically after bolus injection of gadoxetate disodium, normal saline, and gadoterate meglumine, administered in random order in a single session. The technologist and volunteer were blinded to the agent. Arterial phase breath-holding duration was timed after each injection, and volunteers reported subjective symptoms. Heart rate (HR) and oxygen saturation were monitored. Images were independently analyzed for motion artifacts by three radiologists. Arterial phase breath-holding duration and motion artifacts after each agent were compared by using the Mann-Whitney U test and the McNemar test. Factors affecting the above outcomes were assessed by using a univariate, multivariable model. Results Arterial phase breath holds were shorter after gadoxetate disodium (mean, 32 seconds ± 19) than after saline (mean, 40 seconds ± 17; P < .001) or gadoterate meglumine (43 seconds ± 21, P < .001) administration. In 80% (35 of 44) of subjects, arterial phase breath holds were shorter after gadoxetate disodium than after both saline and gadoterate meglumine. Three (7%) of 44 volunteers had severe arterial phase motion artifacts after gadoxetate disodium administration, one (2%; P = .62) had them after gadoterate meglumine administration, and none (P = .25) had them after saline administration. HR and oxygen saturation changes were not significantly associated with contrast agent. Conclusion Maximal hepatic arterial phase breath-holding duration is reduced after gadoxetate disodium administration in healthy volunteers, and reduced breath-holding duration is associated with motion artifacts. © RSNA, 2016.

Impact of Infection on Stroke Morbidity and Outcomes.

Each year, millions of persons worldwide are disabled by stroke. The burden of stroke is expected to increase as a consequence of growth in our elderly population. Outcome is dependent upon limitation of secondary medical processes in the acute setting that lead to deterioration and increased long-term disability. The prevalence of infection after stroke is greater that seen in other medical conditions with similar acuity and its impact upon morbidity and mortality is substantial. Physical impairment and immune modulation are chief determinants in rate of infection after stroke. Each of these factors has been a target for therapeutic intervention. Current best practices for acute stroke management implement strategies for prevention, prompt identification, and treatment of infection. Novel therapies are currently being explored which have the opportunity to greatly minimize infectious complications following stroke. Fever commonly accompanies infection and independently influences stroke outcome. Targeted temperature management provides an additional chance to improve stroke recovery.

Changes in Physician Decision Making after CT: A Prospective Multicenter Study in Primary Care Settings.

Purpose To determine the effect of computed tomography (CT) results on physician decision making in three common clinical scenarios in primary care. Materials and Methods This research was approved by the institutional review board (IRB) and was HIPAA compliant. All physicians consented to participate with an opt-in or opt-out mechanism; patient consent was waived with IRB approval. In this prospective multicenter observational study, outpatients referred by primary care providers (PCPs) for CT evaluation of abdominal pain, hematuria, or weight loss were identified. Prior to CT, PCPs were surveyed to elicit their leading diagnosis, confidence in that diagnosis (confidence range, 0%-100%), a rule-out diagnosis, and a management plan if CT were not available. Surveys were repeated after CT. Study measures were the proportion of patients in whom leading diagnoses and management changed (PCP management vs specialist referral vs emergency department transfer), median changes in diagnostic confidence, and the proportion of patients in whom CT addressed rule-out diagnoses. Regression analyses were used to identify associations between study measures and site and participant characteristics. Specifically, logistic regression analysis was used for binary study measures (change in leading diagnosis, change in management), and linear regression analysis was used for the continuous study measure (change in diagnostic confidence). Accrual began on September 5, 2012, and ended on June 28, 2014. Results In total, 91 PCPs completed pre- and post-CT surveys in 373 patients. In patients with abdominal pain, hematuria, or weight loss, leading diagnoses changed after CT in 53% (131 of 246), 49% (36 of 73), and 57% (27 of 47) of patients, respectively. Management changed in 35% (86 of 248), 27% (20 of 74), and 54% (26 of 48) of patients, respectively. Median absolute changes in diagnostic confidence were substantial and significant (+20%, +20%, and +19%, respectively; P ≤ .001 for all); median confidence after CT was high (90%, 88%, and 80%, respectively). PCPs reported CT was helpful in confirming or excluding rule-out diagnoses in 98% (184 of 187), 97% (59 of 61), and 97% (33 of 34) of patients, respectively. Significant associations between primary measures and site and participant characteristics were not identified. Conclusion Changes in PCP leading diagnoses and management after CT were common, and diagnostic confidence increased substantially. © RSNA, 2016 Online supplemental material is available for this article.

CT in the Emergency Department: A Real-Time Study of Changes in Physician Decision Making.

PURPOSE: To determine how physicians' diagnoses, diagnostic uncertainty, and management decisions are affected by the results of computed tomography (CT) in emergency department settings. MATERIALS AND METHODS: This study was approved by the institutional review board and compliant with HIPAA. Data were collected between July 12, 2012, and January 13, 2014. The requirement to obtain patient consent was waived. In this prospective, four-center study, patients presenting to the emergency department who were referred for CT with abdominal pain, chest pain and/or dyspnea, or headache were identified. Physicians were surveyed before and after CT to determine the leading diagnosis, diagnostic confidence (on a scale of 0% to 100%), alternative "rule out" diagnosis, and management decisions. Primary measures were the proportion of patients for whom the leading diagnosis or admission decision changed and median changes in diagnostic confidence. Secondary measures addressed alternative diagnoses and return-to-care visits (eg, to emergency department) at 1-month follow-up. Regression analysis was used to identify associations between primary measures and site and participant characteristics. RESULTS: Both surveys were completed for 1280 patients by 245 physicians. The leading diagnosis changed in 235 of 460 patients with abdominal pain (51%), 163 of 387 with chest pain and/or dyspnea (42%), and 103 of 433 with headache (24%). Pre-CT diagnostic confidence was inversely associated with the likelihood of a diagnostic change (P < .0001). Median changes in confidence were substantial (increases of 25%, 20%, and 13%, respectively, for patients with abdominal pain, chest pain and/or dyspnea, and headache; P < .0001); median post-CT confidence was high (95% for all three groups). CT helped confirm or exclude at least 95% of alternative diagnoses. Admission decisions changed in 116 of 457 patients with abdominal pain (25%), 72 of 387 with chest pain and/or dyspnea (19%), and 81 of 426 with headache (19%). During follow-up, 70 of 450 patients with abdominal pain (15%), 53 of 387 with chest pain and/or dyspnea (14%), and 49 of 433 with headache (11%) returned for the same indication. In general, changes in leading diagnosis, diagnostic confidence, and admission decisions were not well explained with site or participant characteristics. CONCLUSION: Physicians' diagnoses and admission decisions changed frequently after CT, and diagnostic uncertainty was alleviated.

Emergency Neurologic Life Support (ENLS): Evolution of Management in the First Hour of a Neurological Emergency.

Emergency neurological life support (ENLS) is an educational program designed to provide users advisory instruction regarding management for the first few hours of a neurological emergency. The content of the course is divided into 14 modules, each addressing a distinct category of neurological injury. The course is appropriate for practitioners and providers from various backgrounds who work in environments of variable medical complexity. The focus of ENLS is centered on a standardized treatment algorithm, checklists to guide early patient care, and a structured format for communication of findings and concerns to other healthcare professionals. Certification and training in ENLS is hosted by the Neurocritical Care Society. This document introduces the concept of ENLS and describes the revisions that constitute this second version.

Emergency Neurological Life Support: Traumatic Brain Injury.

Traumatic Brain Injury (TBI) was chosen as an Emergency Neurological Life Support topic due to its frequency, the impact of early intervention on outcomes for patients with TBI, and the need for an organized approach to the care of such patients within the emergency setting. This protocol was designed to enumerate the practice steps that should be considered within the first critical hour of neurological injury.

Hypomagnesemia in Intracerebral Hemorrhage.

BACKGROUND: Magnesium (Mg) is an essential element for the body's normal physiological functioning. It has a major role in modulating vascular smooth muscle tone and peripheral arterial resistance. A low serum Mg level on admission (HMg0) has been associated with more severe presentation in patients with subarachnoid hemorrhage. However, data on HMg0 specifically in relation to intracerebral hemorrhage (ICH) are scarce. We sought to determine the incidence and clinical significance of HMg0 in patients with ICH. METHODS: We reviewed the records of consecutive patients with ICH over a 2-year period. Data collected included initial Mg levels (Mg0), clinical and radiologic characteristics on presentation, and discharge outcomes. Regression analysis was performed to look for any association of low Mg0 with admission blood pressure (BP) and Glasgow Coma Scale (GCS) scores. We also examined the correlation of HMg0 with clinical/radiologic features, admission severity (based on the ICH score), and poor outcome on discharge. RESULTS: In all, 33.6% presented with HMg0. Mg0 levels were negatively associated with systolic BP presentation (P < 0.0001) and positively associated with the initial GCS scores (P = 0.01). Multivariate logistic regression showed an association between HMg0 and severity at presentation (P = 0.03), but not with poor outcome on discharge (P = 0.26). CONCLUSIONS: HMg0 occurs in one third of patients with ICH and is associated with more severe presentation and intraventricular hemorrhage. Mg levels on admission correlate inversely with systolic BP and directly with GCS scores at presentation. HMg0 does not influence outcomes at discharge.

Admission Leukocytosis in Intracerebral Hemorrhage: Associated Factors and Prognostic Implications.

BACKGROUND AND PURPOSE: Leukocytosis is a reaction that is usually, but not always, associated with an infectious process. There is very little data on the significance of admission leukocytosis (AL) in patients with intracerebral hemorrhage (ICH). The purpose of this study was to investigate the associated clinical and radiologic findings and prognostic significance of AL in patients with ICH. METHODS: We retrospectively reviewed the records of consecutive ICH patients admitted over a 2-year period. Key data we collected included ICH size, location, intraventricular hemorrhage (IVH), age, admission Glasgow Coma Scale (GCS0) score, peak leukocyte count and temperature in the first 24 h of hospitalization, and outcomes on discharge. Severity of IVH was calculated using the Graeb Scale. Logistic regression was performed to determine association of variables. RESULTS: In 128 consecutive ICH patients, AL was present in 41.4 %. AL was significantly associated with presence (OR 2.28, 95 % CI 1.11-4.68; p = 0.024), but not severity of IVH and with admission GCS0. Leukocyte count showed a strong association with IVH (p = 0.01) and with decreasing GCS0 (p = 0.007). There was no correlation between AL and poor outcome at discharge. There was also no evidence of infection in any patient with AL. CONCLUSION: AL in ICH patients is often non-infectious, strongly associated with the presence of IVH, but not specifically an ominous indicator for outcome. Leukocyte count has an inverse relationship with GCS0. Prospective studies are needed to confirm these findings.

Aspirin and intracerebral hemorrhage: Where are we now?

For the past 3 decades, aspirin has been widely used for prevention of ischemic stroke and myocardial infarction. Although the evidence supporting the effectiveness of aspirin in prevention of vascular events is clear, data regarding the risk of acute and recurrent intracerebral hemorrhage related to the use of this medication have been conflicting. We review past and contemporary data on aspirin use in relation to intracerebral hemorrhage.

Enrollment of research subjects through telemedicine networks in a multicenter acute intracerebral hemorrhage clinical trial: design and methods.

BACKGROUND: Enrollment of subjects in acute stroke trials is often hindered by narrow timeframes, because a large proportion of patients arrive via transfers from outside facilities rather than primary arrival at the enrolling hospital. RATIONALE: Telemedicine networks have been increasingly used for provision of care for acute stroke patients at facilities outside of major academic centers. Treatment decisions made through telemedicine networks in patients with acute ischemic stroke have been shown to be safe, reliable, and effective. With the expanding use of this technology and the impediments to enrolling subjects into clinical trials, this approach can be applied successfully to the field of clinical research. METHODS AND CONCLUSIONS: The Antihypertensive Treatment of Acute Cerebral Hemorrhage II trial is a phase III randomized multicenter trial that has developed a protocol in collaboration with participating sites to implement the use of telemedicine networks for the enrollment of research subjects. The protocol describes the operating procedures and legal and Institutional Review Board perspectives for its implementation.

Enrollment of Research Subjects through Telemedicine Networks in a Multicenter Acute Intracerebral Hemorrhage Clinical Trial: Design and Methods.

BACKGROUND: Enrollment of subjects in acute stroke trials is often hindered by narrow timeframes, because a large proportion of patients arrive via transfers from outside facilities rather than primary arrival at the enrolling hospital. RATIONALE: Telemedicine networks have been increasingly utilized for provision of care for acute stroke patients at facilities outside of major academic centers. Treatment decisions made through Telemedicine networks in patients with acute ischemic stroke have been shown to be safe, reliable, and effective. With the expanding use of this technology and the impediments to enrolling subjects into clinical trials, this approach can be applied successfully to the field of clinical research. METHODS AND CONCLUSIONS: The antihypertensive treatment of acute cerebral hemorrhage II trial is a phase III randomized multicenter trial that has developed a protocol in collaboration with participating sites to implement the use of Telemedicine networks for the enrollment of research subjects. The protocol describes the operating procedures and legal and Institutional Review Board perspectives for its implementation.

FDG-PET/CT characterization of adrenal nodules: diagnostic accuracy and interreader agreement using quantitative and qualitative methods.

PURPOSE: To determine interreader agreement and diagnostic accuracy across varying levels of reader experience using qualitative and quantitative methods of evaluating adrenal nodules using ((18)F)-fluorodeoxyglucose-positron emission tomography/computed tomography. METHODS: 132 adrenal nodules (96 adenomas, 36 metastases) were retrospectively identified in 105 patients (49 men and 56 women, mean age 66 years, age range 45-85 years) with a history of lung cancer who underwent ((18)F)-fluorodeoxyglucose-positron emission tomography/computed tomography. For each nodule, three readers independently performed one qualitative and two quantitative measurements: visual assessment, standardized uptake value (SUVmax), and standard uptake ratio (SUVratio). Interreader agreement was calculated using percent agreement with κ statistic for qualitative analysis and intraclass correlation coefficient (ICC) for quantitative analysis. Accuracy, sensitivity, and specificity for distinguishing benign from malignant adrenal nodules were calculated for each method. RESULTS: Percent agreement between readers for visual (qualitative) assessment was 92% to 96% and κ statistic was 0.79 to 0.90 (95% confidence limits 0.66-0.99). ICC for SUVmax was 92% to 99% (95% CL 0.8-1.0), and ICC for SUVratio was 89% to 99% (95% CL 0.74-0.99). For diagnosis of malignancy, mean sensitivity and specificity for visual assessment were 80% and 97%, respectively. Mean sensitivity and specificity for SUVmax were 91% and 81%, respectively; for SUVratio, 90% and 80%. Mean diagnostic accuracy was 93%, 83%, and 84% for visual assessment, SUVmax, and SUVratio, respectively. CONCLUSION: Excellent interreader agreement is seen for quantitative and qualitative methods of distinguishing benign from malignant adrenal nodules. Qualitative analysis demonstrated higher accuracy but lower sensitivity compared with quantitative analysis.