Daria Manos

Inter-observer agreement using the Canadian Emergency Department Triage and Acuity Scale

OBJECTIVE To determine the inter-observer agreement on triage assignment by first-time users with diverse training and background using the Canadian Emergency Department Triage and Acuity Scale (CTAS). METHODS Twenty emergency care providers (5 physicians, 5 nurses, 5 Basic Life Support paramedics and 5 Advanced Life Support paramedics) at a large urban teaching hospital participated in the study. Observers used the 5-level CTAS to independently assign triage levels for 42 case scenarios abstracted from actual emergency department patient presentations. Case scenarios consisted of vital signs, mode of arrival, presenting complaint and verbatim triage nursing notes. Participants were not given any specific training on the scale, although a detailed one-page summary was included with each questionnaire. Kappa values with quadratic weights were used to measure agreement for the study group as a whole and for each profession. RESULTS For the 41 case scenarios analyzed, the overall agreement was significant (quadratic-weighted K = 0.77, 95% confidence interval, 0.76-0.78). For all observers, modal agreement within one triage level was 94.9%. Exact modal agreement was 63.4%. Agreement varied by triage level and was highest for Level I (most urgent). A reasonably high level of intra- and inter-professional agreement was also seen. CONCLUSIONS Despite minimal experience with the CTAS, inter-observer agreement among emergency care providers with different backgrounds was significant.

The Lung Reporting and Data System (LU-RADS): A Proposal for Computed Tomography Screening

Despite the positive outcome of the recent randomized trial of computed tomography (CT) screening for lung cancer, substantial implementation challenges remain, including the clear reporting of relative risk and suggested workup of screen-detected nodules. Based on current literature, we propose a 6-level Lung-Reporting and Data System (LU-RADS) that classifies screening CTs by the nodule with the highest malignancy risk. As the LU-RADS level increases, the risk of malignancy increases. The LU-RADS level is linked directly to suggested follow-up pathways. Compared with current narrative reporting, this structure should improve communication with patients and clinicians, and provide a data collection framework to facilitate screening program evaluation and radiologist training. In overview, category 1 includes CTs with no nodules and returns the subject to routine screening. Category 2 scans harbor minimal risk, including <5 mm, perifissural, or long-term stable nodules that require no further workup before the next routine screening CT. Category 3 scans contain indeterminate nodules and require CT follow up with the interval dependent on nodule size (small [5-9 mm] or large [≥10 mm] and possibly transient). Category 4 scans are suspicious and are subdivided into 4A, low risk of malignancy; 4B, likely low-grade adenocarcinoma; and 4C, likely malignant. The 4B and 4C nodules have a high likelihood of neoplasm simply based on screening CT features, even if positron emission tomography, needle biopsy, and/or bronchoscopy are negative. Category 5 nodules demonstrate frankly malignant behavior on screening CT, and category 6 scans contain tissue-proven malignancies.

Computer Vision Tool and Technician as First Reader of Lung Cancer Screening CT Scans

Objectives: To implement a cost‐effective low‐dose computed tomography (LDCT) lung cancer screening program at the population level, accurate and efficient interpretation of a large volume of LDCT scans is needed. The objective of this study was to evaluate a workflow strategy to identify abnormal LDCT scans in which a technician assisted by computer vision (CV) software acts as a first reader with the aim to improve speed, consistency, and quality of scan interpretation. Methods: Without knowledge of the diagnosis, a technician reviewed 828 randomly batched scans (136 with lung cancers, 556 with benign nodules, and 136 without nodules) from the baseline Pan‐Canadian Early Detection of Lung Cancer Study that had been annotated by the CV software CIRRUS Lung Screening (Diagnostic Image Analysis Group, Nijmegen, The Netherlands). The scans were classified as either normal (no nodules ≥1 mm or benign nodules) or abnormal (nodules or other abnormality). The results were compared with the diagnostic interpretation by Pan‐Canadian Early Detection of Lung Cancer Study radiologists. Results: The overall sensitivity and specificity of the technician in identifying an abnormal scan were 97.8% (95% confidence interval: 96.4–98.8) and 98.0% (95% confidence interval: 89.5–99.7), respectively. Of the 112 prevalent nodules that were found to be malignant in follow‐up, 92.9% were correctly identified by the technician plus CV compared with 84.8% by the study radiologists. The average time taken by the technician to review a scan after CV processing was 208 ± 120 seconds. Conclusions: Prescreening CV software and a technician as first reader is a promising strategy for improving the consistency and quality of screening interpretation of LDCT scans.

Predicting EGFR mutation status in lung cancer:Proposal for a scoring model using imaging and demographic characteristics

ObjectiveTo determine if a combination of CT and demographic features can predict EGFR mutation status in bronchogenic carcinoma.MethodsWe reviewed demographic and CT features for patients with molecular profiling for resected non-small cell lung carcinoma. Using multivariate logistic regression, we identified features predictive of EGFR mutation. Prognostic factors identified from the logistic regression model were then used to build a more practical scoring system.ResultsA scoring system awarding 5 points for no or minimal smoking history, 3 points for tumours with ground glass component, 3 points for airbronchograms, 2 points for absence of preoperative evidence of nodal enlargement or metastases and 1 point for doubling time of more than a year, resulted in an AUROC of 0.861. A total score of at least 8 yielded a specificity of 95 %. On multivariate analysis sex was not found to be predictor of EGFR status.ConclusionsA weighted scoring system combining imaging and demographic data holds promise as a predictor of EGFR status. Further studies are necessary to determine reproducibility in other patient groups. A predictive score may help determine which patients would benefit from molecular profiling and may help inform treatment decisions when molecular profiling is not possible.Key points• EGFR mutation-targeted chemotherapy for bronchogenic carcinoma has a high success rate.• Mutation testing is not possible in all patients.• EGFR associations include subsolid density, slow tumour growth and minimal/no smoking history.• Demographic or imaging features alone are weak predictors of EGFR status.• A scoring system, using imaging and demographic features, is more predictive.

Diagnostic Reference Levels and Monitoring Practice Can Help Reduce Patient Dose From CT Examinations

OBJECTIVE The purpose of this study is to establish provincial diagnostic reference levels (DRLs) and to determine whether this process may help reduce the patient radiation dose from the most frequently performed CT examinations. MATERIALS AND METHODS We investigated the following CT examinations: head, chest, low-dose chest, abdomen and pelvis, and chest, abdomen, and pelvis examinations. The sample for each protocol included 15 patients of average body weight (mean [± SD], 70 ± 20 kg). The differences in dose between scanners were evaluated using one-way ANOVA. Correlations between dose, scanner age, and the number of detector rows were assessed using the Pearson correlation coefficient. A sample of abdominal and chest examinations were randomized and blinded for review by experienced radiologists who graded diagnostic image quality. Provincial DRLs were calculated as the 75th percentile of patient dose distributions. For hospitals with doses exceeding the DRLs, dose reduction was recommended, followed by another survey. RESULTS The initial survey included data of 1185 patients, and an additional 180 patients were surveyed after protocol optimization. The differences between the mean values of the dose distributions from each scanner were statistically significant (p < 0.05) for all examinations. The variation was greatest for low-dose chest CT, with a greater than fivefold difference in the mean dose values noted between scanners. A very weak correlation was found between dose and scanner age or the number of detector rows. Analysis of image quality revealed no statistically significant differences in any scoring categories, with the exception of the noise category in abdominal imaging. Implementation of the DRLs allowed a reduction in patient dose of up to 41% as a result of a protocol change. CONCLUSION Establishing provincial DRLs allows an effective reduction in patient dose without resulting in degradation of image quality.

Canadian Association of Radiologists: Guide on Computed Tomography Screening for Lung Cancer

Thepast several years have seen the publication of the results of several major studies, evaluating the use of low-dose computed tomography (LDCT) scanning in the screening of high-risk individuals for lung cancer. Many major U.S. organizations have issued guidelines in support of performing lung cancer screening in appropriate populations, and organized screening programs are becomingwell established in theUnited States. In Canada, however, there are currently very few documents outlining screening recommendations. Cancer Care Ontario issued a statement on lung cancer screening in 2013 [1] and the Canadian Task Force on PreventiveHealth Care has just published new guidelines for lung cancer screening [2]. There are pilot projects underway in some provinces, as well as smaller regional centres. There is also growing concern about opportunistic screening being performed outside of organized screening programs. Although this discussion is outside the scope of the document, the Canadian Association of Radiologists (CAR) does recommend that individual provinces undertake a provincial screening program with a provincial registry, respecting the limitations and constraints of provincial budgets. There are currently a number of guidelines in circulation. While most guidelines agree that LDCT screening only be provided for individuals at high risk for lung cancer, there are slight differences among these guidelines as to the definition of high risk individuals. It is important to recognize that we

Managing Incidentalomas Safely: Do Computed Tomography Requisitions Tell Us What We Need to Know?

Purpose Technological advancements and the ever-increasing use of computed tomography (CT) have greatly increased the detection of incidental findings, including tiny pulmonary nodules. The management of many “incidentalomas” is significantly influenced by a patients history of cancer. The study aim is to determine if CT requisitions include prior history of malignancy. Methods Requisitions for chest CTs performed at our adult tertiary care hospital during April 2012 were compared to a cancer history questionnaire, administered to patients at the time of CT scan. Patients were excluded from the study if the patient questionnaire was incomplete or if the purpose of the CT was for cancer staging or cancer follow-up. Results A total of 569 CTs of the chest were performed. Of the 327 patients that met inclusion criteria, 79 reported a history of cancer. After excluding patients for whom a history of malignancy could not be confirmed through a chart review and excluding nonmelanoma skin cancer, dysplasia, and in situ neoplasm, 68 patients were identified as having a history of malignancy. We found 44% (95% confidence interval [0.32-0.57]) of the chest CT requisitions for these 68 patients did not include the patients history of cancer. Of the malignancies that were identified by patient questionnaire but omitted from the clinical history provided on the requisitions, 47% were malignancies that commonly metastasize to the lung. Conclusions A significant number of requisitions failed to disclose a history of cancer. Without knowledge of prior malignancy, radiologists cannot comply with current guidelines regarding the reporting and management of incidental findings.