Agreement Intraclass Research Articles

Ranking the Relative Importance of Image Quality Features in CT by Consensus Survey

ObjectiveThis study sought to determine consensus opinions from subspecialty radiologists and imaging physicists on the relative importance of image quality features in CT. MethodsA prospective survey of subspecialty radiologists and medical physicists was conducted to collect consensus opinions on the relative importance of ten image quality features: axial sharpness, blooming, contrast, longitudinal sharpness, low contrast axial sharpness, metal artifact, motion, noise magnitude, noise texture, and streaking. The survey was first sent to subspecialty radiologists in volunteer leadership roles in the American College of Radiology and Radiological Society of North America, thereafter relying on snowball sampling. Surveyed subspecialties were abdominal, cardiac, emergency, musculoskeletal, neuro, pediatric, and thoracic radiology, and medical physics. Individual respondents’ ratings were normalized for calculation of mean normalized ratings and priority rankings for each feature within subspecialties. Also calculated were intraclass correlation coefficients across image quality features within subspecialties, and analysis of variance across subspecialties within each feature. ResultsMost subspecialties had moderate to excellent intraclass agreement. For every radiology subspecialty except musculoskeletal, motion was the most important image quality feature. There was agreement across subspecialties that axial sharpness and contrast are only moderately important. There was disagreement across subspecialties on the relative importance of noise magnitude. Blooming was highly important to cardiac radiologists, and noise texture was highly important to musculoskeletal radiologists. ConclusionImage quality preferences differ based on clinical tasks and challenges in each anatomical radiology subspecialty. CT image analysis and development of quantitative measures of quality and protocol optimization—and related policy initiatives—should be specific to radiology subspecialty.

Evaluation of brachial plexus stiffness in different arm and head positions by sonoelastography.

Intraoperative positioning-related nerve injuries, particularly those affecting the brachial plexus, are concerning complications believed to arise from stretching and/or compression of peripheral nerves. Although sonoelastography, a new ultrasound technology, is emerging as a valuable tool in the musculoskeletal system, its utility in evaluating peripheral nerves remains unclear. This study aimed to utilize sonoelastography to assess the brachial plexus during surgery, specifically investigating changes in its stiffness values in relation to different head and arm positions. In this prospective cohort study, bilateral brachial plexuses of 8 volunteers in 3 different positions were enrolled. Using a high-frequency linear probe, the stiffness of the brachial plexus was quantitatively measured in kilopascals (kPa) under 3 different positions: neutral, head rotated, and head rotated with arm hyperabducted. Intra-class agreement was evaluated. The stiffness of the brachial plexus was 7.39 kPa in the neutral position (NP), 10.28 kPa with head rotation, and 17.24 kPa when the head was turned, and the ipsilateral arm was hyperabducted. Significant increases were observed in stiffness values when the head was turned, whether ipsilaterally or contralaterally, and during hyperabduction of the arm while the head was turned (for all P < .001). Strong intra-class correlations were found for the measurements of stiffness values (ICC = 0.988-0.989; P < .001; Cronbach Alpha = 0.987-0.989). Sonoelastography revealed significant increases in the stiffness of the brachial plexus with various head rotations and arm positions compared to the neutral state. These findings suggest that sonoelastography could potentially serve as a valuable tool for assessing the risk of brachial plexus injury during surgery and for guiding optimal patient positioning. Further research with larger sample sizes is needed to establish definitive clinical applications.

Construct Validity and Reproducibility of Handheld Ultrasound Devices in Carotid Artery Diameter Measurement.

The construct validity and reproducibility of three commonly used handheld ultrasound (US) devices in measuring carotid arterial diameter was evaluated: Telemed MicrUs EXT-1H (Telemed, Vilnius, Lithuania), Butterfly iQ (Butterfly Network, Inc., Guilford, CT, USA) and Philips Lumify (Philips Healthcare, Best, The Netherlands). An in vitro setup was built to evaluate construct validity, compared with high-end US, and intra-observer variability of handheld US devices. Handheld devices showed a mean difference of 0.023 ± 0.030 cm, 0.012 ± 0.037 cm and 0.009 ± 0.046 cm for, respectively, Telemed, Butterfly and Lumify in comparison with high-end US devices. Intraclass agreement with the high-end system as well as intra-observer variability for handheld US devices was classified as excellent, with all values greater than 0.95. Subsequently, inter-observer variability of handheld US devices was investigated in an in vivo setup with 20 healthy volunteers. Inter-observer variability was classified as excellent for Telemed (0.901), good for Lumify (0.827) and moderate for Butterfly (0.684) with a difference of, respectively, 0.005 ± 0.031 cm, 0.020 ± 0.050 cm and -0.003 ± 0.033 cm. In conclusion, handheld US devices demonstrated an excellent construct validity and intra-observer variability. Additionally, excellent-to-good inter-observer variability for Telemed and Lumify was observed, and Butterfly demonstrated a moderate inter-observer agreement. These results indicate that handheld US devices are effective for measuring carotid arterial diameter.

Noninvasively predict the micro-vascular invasion and histopathological grade of hepatocellular carcinoma with CT-derived radiomics

ObjectivesThis research aims to predict the micro-vascular invasion and histopathologic grade of hepatocellular carcinoma with the CT-derived radiomics. MethodsThe clinical and image data of 82 patients were accessed from the TCGA-LIHC collection in The Cancer Imaging Archive. Then the radiomics features were extracted from the CT images. For obtaining the appropriate feature subset, the redundant features were removed by means of intra-class agreement analysis, the Student t test, LASSO-regression and support vector machine (SVM) Recursive feature elimination (SVM-RFE). Then several machine-learning-based classifiers including SVM and random forest (RF) were established. To accurately evaluate the tumor grade and MVI with the integration of the Radiomics and clinical insights, the nomogram-based clinical models were constructed. The diagnostic performance was evaluated with ROC analysis. Results7 and 10 radiomics features were selected via LASSO regression and SVM-RFE for identifying the tumor grade with regard to 13 and 10 features selected via LASSO regression and SVM-RFE for evaluating the MVI. The combination of the classifier—RF and the selection strategy of SVM-RFE yielded the best performance for grading HCC (AUC: 0.898). Differently, the combination of the classifier—RF and the selection strategy of LASSO regression resulted in the best performance for identifying MVI (AUC: 0.876). Finally, two nomograms were constructed with radiomics score (Rscore) and clinical risk factors, which showed excellent predictive value for both tumor grade (AUC: 0.928) and MVI (AUC: 0.945). ConclusionCT-derived radiomics were valuable for noninvasively assessing the micro-vascular invasion and histopathologic grade of hepatocellular carcinoma.

Test\u2013retest reliability of the EQ-5D-5L and the reworded QOLIBRI-OS in the general population of Italy, the Netherlands, and the United Kingdom

PurposeTo assess the test–retest reliability of the EQ-5D-5L and the reworded Quality of Life After Traumatic Brain Injury Overall Scale (QOLIBRI-OS) for the general population of Italy, the Netherlands, and the United Kingdom (UK).MethodsThe sample contains 1864 members of the general population (aged 18–75 years) of Italy, the Netherlands, and the UK who completed a web-based questionnaire at two consecutive time points. The survey included items on gender, age, level of education, occupational status, household annual income, chronic health status, and the EQ-5D-5L and reworded QOLIBRI-OS instrument. Test–retest reliability of the EQ-5D-5L dimensions, EQ-5D-5L summary index, EQ VAS, reworded QOLIBRI-OS dimensions and reworded QOLIBRI-OS level sum score was examined by Gwet’s Agreement Coefficient (Gwet’s AC) and Intraclass Correlation Coefficient (ICC).ResultsGwet’s AC ranged from 0.64 to 0.97 for EQ-5D-5L dimensions. The ICC ranged from 0.73 to 0.84 for the EQ-5D-5L summary index and 0.61 to 0.68 for EQ VAS in the three countries. Gwet’s AC ranged from 0.35 to 0.55 for reworded QOLIBRI-OS dimensions in the three countries. The ICC ranged from 0.69 to 0.77 for reworded QOLIBRI-OS level sum score.ConclusionTest–retest reliability of the EQ-5D-5L administered via a web-based questionnaire was substantial to almost perfect for the EQ-5D-5L dimensions, good for EQ-5D-5L summary index, and moderate for the EQ VAS. However, test–retest reliability was less satisfactory for the reworded QOLIBRI-OS. This indicates that the web-based EQ-5D-5L is a reliable instrument for the general population, but further research of the reworded QOLIBRI-OS is required.

Child- compared with parent-report ratings on psychosocial measures following a mild traumatic brain injury among youth with persistent post-concussion symptoms

ABSTRACT Primary Objective: To compare child- and parent-report ratings on the Health Behavior Inventory, Revised Child Anxiety and Depression Scale-Short Version (anxiety subscale), Patient Health Questionnaire-9, and Pediatric Quality of Life InventoryTM among children with persistent post-concussive symptoms following a sports- or recreation-related concussion, overall and by child age and gender. Research Design: Cross-sectional study examining baseline data from a randomized, comparative effectiveness trial. Methods and Procedures: Inter-rater reliability was assessed using two-way random effects model (absolute agreement) intraclass correlations, correlations were examined using Spearman’s rho, mean differences were determined using paired t-tests, and agreement was examined using Bland–Altman plots. Main Outcomes and Results: The final analytic sample was 200 parent–child dyads [child Mage = 14.7 (95% CI: 14.5, 15.0)]. Reliability and correlations were modest overall. When considering child age and gender, reliability ranged from poor to excellent (−1.01–0.95) and correlations ranged from weak to strong (−0.64–0.94). Overall, children reported more symptoms but better functioning than parents, and mean differences in scores were greater among females (versus males) and ages 16–18 (versus younger groups). Conclusions: Findings should inform the use and interpretation of psychosocial measures when developing appropriate youth concussion treatment plans.

Tibial torsion analysis in computed tomography: development and validation of a real 3D measurement technique

PurposePathological tibial torsion is known to negatively influence the functionality of the lower extremity, and therefore, its assessment might play an important role. While 3D imaging is used for many examinations of the musculoskeletal system, for the determination of tibial torsion no 3D measurement technique has been available so far. We developed a 3D measurement method and assess its interobserver reliability as well as its correlation with standard 2D measurement methods.MethodsCT scans of 82 tibiae in 79 patients with a mean age of 41 years were included. A novel 3D measurement technique was developed and applied. Measurements were compared with two frequently used 2D measurement methods. ICC (intraclass correlation coefficient) for the new technique was determined and compared to the 2D measurement method. Furthermore, differences between left and right legs as well as between males and females were assessed.ResultsThe ICC for the 2D methods was 0.917 and 0.938, respectively. For the 3D measurements, ICCs were calculated to be 0.954 and 0.950. Agreement between 2 and 3D methods was moderate to good with ICCs between 0.715 and 0.795. Torsion values for left and right legs did not differ significantly in 2D and in 3D (26.2 vs 28.5° and 27.2 vs. 25.9°). The same is true for the differences between male and female in 2D and 3D (26.2 vs. 29.6° and 25.0 vs. 31.2°).ConclusionThe newly developed 3D measurement technique shows a high intraclass agreement and offers an applicable opportunity to assess the tibial torsion three-dimensionally.

Optimizing diagnostic imaging data using LI-RADS and the Likert scale in patients with hepatocellular carcinoma.

PurposeThe study aimed to compare the diagnostic performance of the Liver Imaging Reporting and Data System (LI-RADS), which incorporates fixed criteria, and the Likert scale (LS), which mainly depends on an overall impression in liver lesion diagnosis.Material and methodsDiagnostic data of 110 hepatic nodules in 103 high-risk patients for hepatocellular carcinoma (HCC) were included. Data including diameter, arterial hyperenhancement, washout, and capsule were reviewed by 2 readers using LI-RADS and LS (range, score 1-5). Inter-reader agreement (IRA), intraclass agreement (ICA), and diagnostic performance were determined by Fleiss, Cohen’s k, and logistic regression, respectively.ResultsThere were 53 triphasic enhanced computed tomography (CT) and 50 dynamic magnetic resonance (MR) examinations. Overall, IRA was excellent (k = 0.898). IRA was good for arterial hyperenhancement (k = 0.705), washout (k = 0.763), and capsule (k = 0.771) and excellent for diameter (k = 0.981) and tumour embolus (k = 0.927). Overall, ICA between LI-RADS and LS was fair 0.32; ICA was good for scores of 1 (k = 0.682), fair for scores of 2 (k = 0.36), moderate for scores of 5 (k = 0.52), but no agreement was found for scores of 3 (k = –0.059) and 4 (k = –0.022). LIRADS produced relatively high accuracy (87.3% vs. 80%), relatively low sensitivity (84.3% vs. 98%), and significantly higher specificity (89.83% vs. 64.4%) and positive likelihood ratio (+LR: 8.29 vs. 2.75) compared to LS approach.ConclusionsLI-RADS revealed higher diagnostic accuracy as compared to LS with statistical proof higher specificity and +LR showing its ability to foretell malignancy in high-risk patients. We recommend the practical application of the LI-RADS system in the detection and treatment response monitoring of patients with HCC.

Adaptation of an instrument to classify neonatal patients into care categories

To adapt and validate a patient classification instrument for neonatal units. Methodological study, with adaptation of the Pediatric Patients Classification Instrument for neonatal patients. After content validation by judges, the instrument was tested for reliability, applied to 33 neonates by two nurses, simultaneously. To assess the agreement among nurses regarding the scores of each patient on the classification scale, an intraclass agreement coefficient was applied. To assess the agreement regarding the classification in care categories, the weighted Kappa coefficient was calculated. The adapted instrument consisted of a total of nine indicators, with three care categories: high dependence on care, semi-intensive care and intensive care. The Content Validity Index varied between 0.85 and 0.92 for items of the instrument. The intraclass agreement was 0.87 and the weighted Kappa for care categories was 0.56. An instrument that allows neonatal patients to be classified into care categories, with satisfactory reliability was validated to support the dimensioning of the nursing team.

Continuous Thermodilution Method to Assess Coronary Flow Reserve

Coronary flow reserve (CFR) is a well-validated flow-based physiological parameter that has shown value in clinical risk stratification. CFR can be invasively assessed, classically by Doppler and, more recently, by thermodilution with saline boluses (CFRthermo-bolus). Alternatively, continuous thermodilution is a novel operator-independent, highly-reproducible technique to invasively quantify maximum absolute coronary flow (AF). This study aimed to assess the feasibility of this method to quantify resting AF and to determine CFR (CFRThermo-infusion) as compared with CFRthermo-bolus. Sixty-two consecutive patients with suspicion of coronary disease and absence of significant epicardial lesions were prospectively investigated. AF at maximal hyperemia (20 mL/min) and at lower infusion rates (6-8-10-12 mL/min) were systematically measured using a dedicated catheter and a temperature/pressure guidewire. The absence of baseline Pd/Pa decrease at 6 (0.15 ± 0.2%), 8 (0.17 ± 0.18%) and 10 mL/min (0.2 ± 0.12%) demonstrated absence of hyperemia at ≤10 mL/min (all p = NS). However, at 12 mL/min hyperemia was confirmed by a significant decrease in Pd/Pa (1.3 ± 1.5%, p <0.01) and increase in AF from 10 mL/min to 12 mL/min (31.4 ± 28.1 mL, p <0.05). All curve tracings at 10 mL/min (129/129, 100%) were adequate versus only (7/15, 53%) and (15/18, 17%) at 6 mL/min, and 8 mL/min, respectively, and this infusion-rate was considered to determine resting-AF. CFRThermo-infusion was determined as the ratio of hyperemic-AF (20 mL/min) by resting-AF (10 mL/min). Mean CFRThermo-infusion was 2.56 ± 0.9 and CFRthermo-bolus 2.49 ± 1. Both parameters showed a good correlation (r = 0.76; p <0.001) and intraclass agreement (ICC = 0.76; p <0.001).The continuous thermodilution method enables to quantify resting-AF providing a novel clinical tool to determine CRF. CFRThermo-infusion shows a good correlation with CFRthermo-bolus..

Assessment of Dietary Intake Using Food Photography and Video Recording in Free-Living Young Adults: A Comparative Study

BackgroundConventional methods of dietary assessment are prone to recall bias and place burden on participants. ObjectiveOur aim was to compare the performance of image-based dietary assessment (IBDA), including food photography (FP) and video recording (VR), with the criterion of weighed food records (WFR). DesignIn this comparative study, participants captured meals using FP and VR before and after consumption, over 2 days. Food type and portion size were assessed using the images and videos. Energy and nutrient intakes (mean of 2 days) were compared against WFR. Participants/settingsEighty-four healthy adults (mean [standard deviation] age = 29 [8] years), recruited through advertisement in Glasgow, UK, between January and August 2016 were enrolled in the study. Eighty participants (95%) (mean [standard deviation] age = 28 [7] years) completed the study and were included in the analysis. Main outcome measuresAgreement in estimated energy and nutrient intake between WFR and IBDA. The IBDA method feasibility was evaluated using a questionnaire. Inter-rater and intra-rater reliability were assessed. Statistical analysis performedThe performance of the IBDA methods against WFR and their inter and intra-rater reliability were tested with Bland-Altman plots and Spearman correlations. Intra-class agreement between methods was assessed using κ statistics. ResultsInter-rater reliability was strong for both IBDA methods in estimating energy intake (ρ-coefficients: FP = 0.80; VR = 0.81). There was no difference in the agreement between the 2 assessors. Intra-rater reliability was high. FP and VR underestimated energy intake by a mean (95% agreement limits) of –13.3% (–56.4% and 29.7%) and –4.5% (–45.5% and 36.4%), respectively. IBDA demonstrated moderate-to-strong correlations in nutrient intake ranking, median ρ-coefficients for all nutrients: FP = 0.73 (interquartile range, 0.09) and VR = 0.82 (interquartile range, 0.02). Inter-class agreement of IBDA methods was moderate compared with the WFR in energy intake estimation. IBDA was more practical and enjoyable than WFR. ConclusionsIBDA and VR in particular demonstrated a moderate-to-strong ability to rank participants’ dietary intake, and considerable group and inter-class agreement compared with the WFR. However, IBDA was found to be unsuitable for assessment in individuals.

Proposal of an Alternative to the AMA Guidelines for the Evaluation of the Cervical ROM

The cervical spine is one of the most frequently injured joints in a car accident. References for the range of motion (ROM) that should be expected in a person are needed to stage the injuries. The two main objectives of this paper are to clinically validate a measuring device for the cervical spine, and to assess if the use of different ROM reference values will render different results from the American Medical Association (AMA) ROM guidelines. The present study is divided into 2 phases, a validation phase with 55 subjects and a case-control phase with 80 subjects. A BTS (Bioengineering Technology and System) system and the EBI-5 (estudio biomecánico integral) system were used for the present investigation. The intraclass correlation agreement value between both measuring devices is considered very good with a Cronbach alpha up to 0.9 in every dimension. Correlations (r) between variables are very high, not showing any values lower than 0.887. All comparisons between using AMA ROM guidelines or normative values presented significant differences (p &lt; 0.05). The EBI-5 system has exhibited good accuracy being paired to a photogrammetric system. The use of guidelines adjusted to age constitute an alternative to the use of the AMA cervical ROM guidelines. Professionals should use age-normalized guidelines as an alternative to the AMA guidelines.

A real 3D measurement technique for the tibial slope: differentiation between different articular surfaces and comparison to radiographic slope measurement

BackgroundThe tibial slope plays an important role in knee surgery. However, standard radiographic measurement techniques have a low reproducibility and do not allow differentiation between medial and lateral articular surfaces. Despite availability of three-dimensional imaging, so far, no real 3D measurement technique was introduced and compared to radiographic measurement, which were the purposes of this study.MethodsComputed tomography scans of 54 knees in 51 patients (41 males and 10 females) with a mean age of 46 years (range 22–67 years) were included. A novel 3D measurement technique was applied by two readers to measure the tibial slope of medial and lateral tibial plateau and rim. A statistical analysis was conducted to determine the intraclass correlation coefficient (ICC) for the new technique and compare it to a standard radiographic measurement.ResultsThe mean 3D tibial slope for the medial plateau and rim was 7.4° and 7.6°, for the lateral plateau and rim 7.5° and 8.1°, respectively. The mean radiographic slope was 6.0°. Statistical analysis showed an ICC between both readers of 0.909, 0.987, 0.918, 0.893, for the 3D measurement of medial plateau, medial rim, lateral plateau and lateral rim, respectively, whereas the radiographic technique showed an ICC of 0.733.ConclusionsThe proposed novel measurement technique shows a high intraclass agreement and offers an applicable opportunity to assess the tibial slope three-dimensionally. Furthermore, the medial and lateral articular surfaces can be measured separately and one can differentiate the slope from the plateau and from the rim. As three-dimensional planning becomes successively more important, our measurement technique might deliver a useful supplement to the standard radiographic assessment in slope related knee surgery.Level of evidenceLevel III, diagnostic study.

Use of SOPARC to assess physical activity in parks: do race/ethnicity, contextual conditions, and settings of the target area, affect reliability?

BackgroundSince its introduction in 2006, SOPARC (Systematic Observation of Play and Recreation in Communities) has become a fundamental tool to quantify park visitor behaviors and characteristics. We tested SOPARC reliability when assessing race/ethnicity, physical activity, contextual conditions at the time of observation, and settings of target areas to understand its utility when trying to account for individual characteristics of users.MethodsWe used 4725 SOPARC observations completed simultaneously by two independent observers to evaluate intraclass correlation and agreement rate between the two observers when trying to assess sex, age group, race/ethnicity, and level of physical activity of urban park users in different park settings. Observations were in 20 New York City parks during Spring and Summer 2017 within the PARC3 project.ResultsObservers counted 25,765 park users with high interobserver reliability (ICC = .94; %Agreement.75). Reliability scores were negatively affected by the population being observed, the intensity of physical activity, and the contextual conditions and settings of the target area at the time of observation. Specific challenges emerged when assessing the combination of physical activity and race/ethnicity.ConclusionsSOPARC training should aim to improve reliability when assessing concurrent measures such as physical activity, race/ethnicity, age, and sex. Similarly, observing crowded park areas with many active users areas may require more observation practice hours.

Evaluation of atrial septal defects with 4D flow MRI\u2014multilevel and inter-reader reproducibility for quantification of shunt severity

PurposeWith the hypothesis that 4D flow can be used in evaluation of cardiac shunts, we seek to evaluate the multilevel and interreader reproducibility of measurements of the blood flow, shunt fraction and shunt volume in patients with atrial septum defect (ASD) in practice at multiple clinical sites.Materials and methodsFour-dimensional flow MRI examinations were performed at four institutions across Europe and the US. Twenty-nine patients (mean age, 43 years; 11 male) were included in the study. Flow measurements were performed at three levels (valve, main artery and periphery) in both the pulmonary and systemic circulation by two independent readers and compared against stroke volumes from 4D flow anatomic data. Further, the shunt ratio (Qp/Qs) was calculated. Additionally, shunt volume was quantified at the atrial level by tracking the atrial septum.ResultsMeasurements of the pulmonary blood flow at multiple levels correlate well whether measuring at the valve, main pulmonary artery or branch pulmonary arteries (r = 0.885–0.886). Measurements of the systemic blood flow show excellent correlation, whether measuring at the valve, ascending aorta or sum of flow from the superior vena cava (SVC) and descending aorta (r = 0.974–0.991). Intraclass agreement between the two observers for the flow measurements varies between 0.96 and 0.99. Compared with stroke volume, pulmonic flow is underestimated with 0.26 l/min at the main pulmonary artery level, and systemic flow is overestimated with 0.16 l/min at the ascending aorta level. Direct measurements of ASD flow are feasible in 20 of 29 (69%) patients.ConclusionBlood flow and shunt quantification measured at multiple levels and performed by different readers are reproducible and consistent with 4D flow MRI.

Handgrip force steadiness in young and older adults: a reproducibility study

BackgroundForce steadiness is a quantitative measure of the ability to control muscle tonus. It is an independent predictor of functional performance and has shown to correlate well with different degrees of motor impairment following stroke. Despite being clinically relevant, few studies have assessed the validity of measuring force steadiness. The aim of this study was to explore the reproducibility of handgrip force steadiness, and to assess age difference in steadiness.MethodIntrarater reproducibility (the degree to which a rating gives consistent result on separate occasions) was investigated in a test-retest design with seven days between sessions. Ten young and thirty older adults were recruited and handgrip steadiness was tested at 5%, 10% and 25% of maximum voluntary contraction (MVC) using Nintendo Wii Balance Board (WBB). Coefficients of variation were calculated from the mean force produced (CVM) and the target force (CVT). Area between the force curve and the target force line (Area) was also calculated. For the older adults we explored reliability using intraclass correlation coefficient (ICC) and agreement using standard error of measurement (SEM), limits of agreement (LOA) and smallest real difference (SRD).ResultsA systematic improvement in handgrip steadiness was found between sessions for all measures (CVM, CVT, Area). CVM and CVT at 5% of MVC showed good to high reliability, while Area had poor reliability for all percentages of MVC. Averaged ICC for CVM, CVT and Area was 0.815, 0.806 and 0.464, respectively. Averaged ICC on 5%, 10%, and 25% of MVC was 0.751, 0.667 and 0.668, respectively. Measures of agreement showed similar trends with better results for CVM and CVT than for Area. Young adults had better handgrip steadiness than older adults across all measures.ConclusionThe CVM and CVT measures demonstrated good reproducibility at lower percentages of MVC using the WBB, and could become relevant measures in the clinical setting. The Area measure had poor reproducibility. Young adults have better handgrip steadiness than old adults.

Subarachnoid space diameter in chromosomally abnormal fetuses at 11–13 weeks’ gestation

Objectives: To examine the subarachnoid space diameters in chromosomally abnormal fetuses at 11–13 weeks’ gestation.Methods: Stored three-dimensional (3D) ultrasound volumes of the fetal head at 11–13 weeks’ gestation from 407 euploid and 88 chromosomally abnormal fetuses (trisomy 21, n = 40; trisomy 18, n = 19; trisomy 13, n = 7; triploidy, n = 14; Turner syndrome, n = 8) were analyzed. The subarachnoid space diameters, measured in the sagittal and transverse planes of the fetal head, in relation to biparietal diameter (BPD) in each group of aneuploidies was compared to that in euploid fetuses. A total of 20 head volumes were randomly selected and all the measurements were recorded by two different observers to examine the interobserver variability in measurements.Results: In euploid fetuses, the anteroposterior, transverse and sagittal diameters of the subarachnoid space increased with BPD. The median of the observed to expected diameters for BPD were significantly increased in triploidy and trisomy 13 but were not significantly altered in trisomies 21 and 18 or Turner syndrome. In triploidy, the subarachnoid space diameters for BPD were above the 95th centile of euploid fetuses in 92.9% (13 of 14) cases. The intraclass reliability or agreement was excellent for all three subarachnoid space diameters.Conclusion: Most fetuses with triploidy at 11–13 weeks’ gestation demonstrate increased subarachnoid space diameters.

Automatic cellularity assessment from post‐treated breast surgical specimens

Neoadjuvant treatment (NAT) of breast cancer (BCa) is an option for patients with the locally advanced disease. It has been compared with standard adjuvant therapy with theaim of improving prognosis and surgical outcome. Moreover, the response of the tumor to the therapy provides useful information for patient management. The pathological examination of the tissue sections after surgery is the gold-standard to estimate the residual tumor and the assessment of cellularity is an important component of tumor burden assessment. In the current clinical practice, tumor cellularity is manually estimated by pathologists on hematoxylin and eosin (H&E) stained slides, the quality, and reliability of which might be impaired by inter-observer variability which potentially affects prognostic power assessment in NAT trials. This procedure is also qualitative and time-consuming. In this paper, we describe a method of automatically assessing cellularity. A pipeline to automatically segment nuclei figures and estimate residual cancer cellularity from within patches and whole slide images (WSIs) of BCa was developed. We have compared the performance of our proposed pipeline in estimating residual cancer cellularity with that of two expert pathologists. We found an intra-class agreement coefficient (ICC) of 0.89 (95% CI of [0.70, 0.95]) between pathologists, 0.74 (95% CI of [0.70, 0.77]) between pathologist #1 and proposed method, and 0.75 (95% CI of [0.71, 0.79]) between pathologist #2 and proposed method. We have also successfully applied our proposed technique on a WSI to locate areas with high concentration of residual cancer. The main advantage of our approach is that it is fully automatic and can be used to find areas with high cellularity in WSIs. This provides a first step in developing an automatic technique for post-NAT tumor response assessment from pathology slides. © 2017 International Society for Advancement of Cytometry.

Abstract 36: Acute Stroke Evolution is in the Eye of the Beholder: Effects of Interrater Variability on Patient Selection and Outcomes in the Mr Witness (nct01282242) Multicenter Thrombolysis Trial

Background: MR WITNESS was a safety trial giving tPA to acute ischemic stroke (AIS) patients with unwitnessed onset with MRI findings of early stroke. A DWI-positive, FLAIR negative pattern has been shown to identify strokes &lt;4.5 hr duration, but visual inspection alone may be unreliable and insensitive. Signal intensity ratios (SIR) of manual outlines (lesion/contralateral side) increase sensitivity but can lead to variability in patient selection. We investigated the influence of interrater variability on clinical and safety outcomes. Methods: Core readers blinded to enrollment status and clinical presentation reviewed MRI of screened patients. The MR WITNESS algorithm enrolled subjects with no visible FLAIR or a pre-specified SIR &lt;1.15. Good outcome was defined as 90 Day modified Rankin Scale (mRS) &lt; 2. SIR consistency was measured with intraclass coefficient (ICC) and reader agreement assessed with Fleiss’ Kappa. Statistical analysis included 2-sided Fisher’s Exact test or Wilcoxon Exact test as appropriate. Results: 201 subjects were screened. 153 baseline MRIs with DWI lesions were reviewed. ICC was 71% (P&lt;.001) and kappa was 67% (P&lt;.0001). Among the 80 subjects enrolled using SIR &lt;1.15 by site reading, 15 (18.8%) subjects would have been excluded based on Core readings. These 15 subjects were younger with worse NIHSS and 90-day mRS (Table). Subset analyses of subjects with pre-stroke mRS&lt;2 showed no statistical difference (P=0.19) between subjects deemed eligible and not eligible by core readers. No difference in hemorrhagic transformation (HT) or good outcome rates was found. Using SIR &lt;1.25 would have only excluded 3 subjects by Core readings, all of whom had HT, and poor 90 day outcomes. Discussion: Although SIR reads between Core and sites showed good agreement, there was still variability in the absolute values. This demonstrates the potential limitation of subjective lesion volume delineation. Automated approaches should be investigated.

Liver Imaging Reporting and Data System:: Substantial Discordance Between CT and MR for Imaging Classification of Hepatic Nodules

The Liver Imaging Reporting and Data System (LI-RADS) is a newly developed nomogram for standardizing the performance and interpretation of liver imaging. However, it is unclear which imaging technique is optimal to exactly define LI-RADS scale. This study aims to determine the concordance of computed tomography (CT) and magnetic resonance imaging (MRI) for the classification of hepatic nodules (HNs) using a LI-RADS scoring system. Major imaging features (arterial hyper-enhancement, washout, pseudo-capsule, diameter, and tumor embolus) on CT versus MRI for 118 HNs in 84 patients with diffuse liver disease were rated independently using LI-RADS by two groups of readers. Inter-reader agreement (IRA) and intraclass agreement was determined by Fleiss and Cohen's kappa (κ). Logistic regression for correlated data was used to compare diagnostic ability. IRA was perfect for determination of nodule size and tumor embolus (κ = 0.94-0.98). IRA was moderate to substantial for determination of arterial hyper-enhancement, washout, and pseudo-capsule (κ = 0.54-0.72). Intraclass agreement between CT and MRI was substantial for determination of washout (0.632 [95% CI: 0.494, 0.771]) and pseudo-capsule (0.670 [95% CI: 0.494, 0.847]), and fair for arterial hyper-enhancement (0.203 [95% CI: 0.051, 0.354]). CT against MR produced false-negative findings of arterial hyper-enhancement by 57.1%, washout by 21.2%, and pseudo-capsule by 42.9%; and underestimated LI-RADS score by 16.9% for LR 3, 37.3% for LR 4, and 8.5% for LR 5. CT produced significantly lower accuracy (54.3% vs 67.8%, P < 0.001) and sensitivity (31.6% vs 71.1%, P < 0.001) than MRI in the prediction of malignancy. There are substantial discordance between CT and MR for stratification of HNs using LI-RADS. MRI could be better than CT in optimizing the performance of LI-RADS.