scholarly journals MRI-Derived Fetal Weight Estimation in the Midpregnancy Fetus: A Method Comparison Study

2021 ◽  
pp. 1-12
Author(s):  
Jacqueline Matthew ◽  
Emily Skelton ◽  
Lisa Story ◽  
Alice Davidson ◽  
Caroline L. Knight ◽  
...  
Keyword(s):  
Interobserver Agreement ◽  
Intraclass Correlation ◽  
Method Comparison ◽  
Relative Difference ◽  
Observer Agreement ◽  
Fetal Weight ◽  
Mri Scans ◽  
Mri Volumetry ◽  
The Mean ◽  
Method Comparison Study

<b><i>Objectives:</i></b> The aim of this study was to compare the standard ultrasound (US) estimated fetal weight (EFW) and MRI volume-derived methods for the midtrimester fetus. <b><i>Methods:</i></b> Twenty-five paired US and MRI scans had the EFW calculated (gestational age [GA] range = 20–26 weeks). The intra- and interobserver variability of each method was assessed (2 operators/modality). A small sub-analysis was performed on 5 fetuses who were delivered preterm (mean GA 29 <sup>+3</sup> weeks) and compared to the actual birthweight. <b><i>Results:</i></b> Two MRI volumetry EFW formulae under-measured compared to US by −10.9% and −14.5% in the midpregnancy fetus (<i>p</i> &#x3c; 0.001) but had excellent intra- and interobserver agreement (intraclass correlation coefficient = 0.998 and 0.993). In the preterm fetus, the mean relative difference (MRD) between the MRI volume-derived EFW (MRI-EFW) and actual expected birthweight (at the scan GA) was −13.7% (−159.0 g, 95% CI: −341.7 to 23.7 g) and −17.1% (−204.6 g, 95% CI: −380.4 to −28.8 g), for the 2 MRI formulae. The MRD was smaller for US at 5.3% (69.8 g, 95% CI: −34.3 to 173.9). <b><i>Conclusions:</i></b> MRI-EFW results should be interpreted with caution in midpregnancy. Despite excellent observer agreement with MRI volumetry, refinement of the EFW formula is needed in the second trimester, for the small and for the GA and preterm fetus to compensate for lower fetal densities.

Comparison of Two Different Ultrasound Systems for the Evaluation of Tissue Doppler Velocities in Fetuses

2015 ◽  
Vol 40 (1) ◽  
pp. 35-40 ◽  
Author(s):  
Mónica Cruz-Lemini ◽  
Brenda Valenzuela-Alcaraz ◽  
Francesc Figueras ◽  
Marta Sitges ◽  
Olga Gómez ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Method Comparison ◽  
Correlation Coefficients ◽  
Tissue Doppler ◽  
Doppler Imaging ◽  
Specific Reference ◽  
Medical Systems ◽  
Intraclass Correlation Coefficients ◽  
Basal Septum ◽  
Method Comparison Study

Introduction: Recent studies have reported variations of up to 30% between different ultrasound machines for tissue Doppler imaging (TDI), a problem that can significantly impact clinical diagnosis, patient management and research studies. The objective of this study was to assess repeatability and agreement between fetal myocardial peak velocities evaluated by TDI with two different ultrasound systems. Materials and Methods: Systolic (S'), early (E') and late (A') diastolic myocardial peak velocities at mitral and tricuspid annuli as well as at the basal septum were evaluated by spectral TDI in 150 fetuses using two different ultrasound systems: Siemens Antares (Siemens Medical Systems, Malvern, Pa., USA) and Vivid Q (General Electric Healthcare, Horten, Norway). A method comparison study was performed, calculating intraclass correlation coefficients (ICC), and agreement was assessed by Bland-Altman plots. Results: Annular peak velocities showed lower values when measured by Vivid Q compared to values measured by Siemens Antares. ICC ranged from 0.07 (septal S') to 0.33 (right A'), showing very poor repeatability for clinical application. Agreement between the two systems was also poor, with high coefficients of variation for all measurements. Conclusions: Fetal annular peak velocities obtained with different ultrasound systems are not directly comparable. This is consistent with previous data in adults and warrants the need of system-specific reference values, suggesting that the same ultrasound machine should be used for longitudinal follow-up.

scholarly journals MRI KNEE BONE AGE: A NOVEL SHORTHAND APPROACH TO REDUCE BONE AGE RADIOGRAPHS IN CHILDREN

2020 ◽  
Vol 8 (4_suppl3) ◽  
pp. 2325967120S0018
Author(s):  
Blake C. Meza ◽  
Scott M. LaValva ◽  
Christopher J. DeFrancesco ◽  
Brendan M. Striano ◽  
Julien T. Aoyama ◽  
...  
Keyword(s):  
Radiation Exposure ◽  
Medical Training ◽  
Skeletal Maturity ◽  
Intraclass Correlation ◽  
Age Determination ◽  
Bone Age ◽  
Observer Agreement ◽  
Rater Reliability ◽  
Knee Mri ◽  
The Mean

Background: Determining bone age in skeletally immature patients is critical for proper management and surgical planning. Pennock et al. recently created and validated a bone age atlas using the ossification pattern of the knee on MRI in pediatric patients, obfuscating the need for a hand radiograph and its associated cost, radiation exposure, and clinical inefficiency. Hypothesis/Purpose: We sought to validate and demonstrate reliability of a novel shorthand method of bone age determination using knee MRI across multiple levels of medical training. Methods: We identified patients who underwent knee MRI and hand bone age radiograph within a ninety-day period. In collaboration with a pediatric musculoskeletal radiologist, stepwise algorithms for predicting bone age on knee MRI were developed- one for males and one for females. Six raters at varying levels of training used the algorithm to assign a bone age for each patient. Intraclass correlation coefficient (ICC) was used to compare each rater’s predicted knee bone age to the Greulich and Pyle (G&P) hand bone age and validate the shorthand algorithm. Inter-rater reliability was also calculated using ICC. Results: Thirty-eight patients (44.7% female) underwent a knee MRI at a mean age of 12.8 years (range 9.3-15.7). The mean time between hand bone age x-ray and knee MRI was 20.2 days (range 0-88). The inter-rater reliability for the application of our shorthand algorithm was 0.81 (95% CI: 0.72 – 0.88), indicating good inter-observer agreement. The shorthand methos was shown to be a good predictor of G&P hand bone age, both for each individual rater (ICC range: 0.73 – 0.80) and the mean knee MRI bone age across all raters (ICC 0.81; 95% CI 0.65 – 0.90). It was also shown to be a consistent predictor of hand bone age across level of training, as medical students (ICC 0.77, 95% CI 0.60-0.88), residents (ICC 0.80, 95% CI 0.65-0.89), and attending physicians (ICC 0.80, 95% CI 0.63-0.89) all achieved strong correlation between predicted knee MRI bone age and G&P hand bone age. Conclusions: This novel shorthand algorithm is a reliable and valid way to determine skeletal maturity using knee MRI. It can be utilized clinically across different levels of radiographic and orthopaedic expertise and reduces the need for hand bone age radiographs and consequential radiation exposure in children. [Figure: see text][Figure: see text][Table: see text]

Anatomical plane and transverse axis of the scapula: Reliability of manual positioning of the anatomical landmarks

2021 ◽  
pp. 175857322110017
Author(s):  
Adrien Jacquot ◽  
Marc-Olivier Gauci ◽  
Manuel Urvoy ◽  
François Boux de Casson ◽  
Julien Berhouet ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Method ◽  
Observer Agreement ◽  
Anatomical Landmarks ◽  
Positioning Error ◽  
Key Points ◽  
The Mean ◽  
Anatomical Plane

Background The aim of our study was to evaluate the accuracy of manual determination of the three key points defining the anatomical plane of the scapula, which conditions the reliability of planning software programs based on manual method. Method We included 82 scapula computed tomography scans (56 pathologic and 26 normal glenoid), excluding truncation and major three-dimensional artifact. Four observers independently picked the three key points for each case. Inter- and intra-observer agreement was calculated for each point, using the intraclass correlation method. The mean error (mm) between the observers was calculated as the diameter of the smallest sphere including the four chosen positions. Results Lower inter-observer agreement was found for the trigonum superoinferior position and for the glenoid center anteroposterior position. The mean positioning error between the four observers was 6.9 mm for the trigonum point, and error greater than 10 mm was recorded in 25% of the cases. The mean positioning error was 3.5 mm for the glenoid center in altered glenoid, compared to 1.8 mm for normal glenoid. Discussion Manual determination of an anatomical plane of the scapula suffers from inaccuracy especially due to the variability in trigonum picking, and in a lesser extent, to the variability of glenoid center picking in altered glenoid.

scholarly journals Evaluation of a rapid turn-over, fully-automated ADAMTS13 activity assay: a method comparison study

2020 ◽  
Vol 50 (3) ◽  
pp. 628-631 ◽  
Author(s):  
Jan Stratmann ◽  
Josephine-Nana Ward ◽  
Wolfgang Miesbach
Keyword(s):  
Atypical Hemolytic Uremic Syndrome ◽  
Method Comparison ◽  
Daily Practice ◽  
Observer Agreement ◽  
Published Data ◽  
Adamts13 Activity ◽  
Comparison Study ◽  
Activity Assay ◽  
Method Comparison Study ◽  
Turn Over

Abstract Thrombotic thrombocytopenic purpura (TTP) is a life-threatening thrombotic microangiopathy caused by severely reduced activity of the von-Willebrand factor-cleaving protease ADAMTS13, mainly caused by anti-ADAMTS-13 antibodies. Although several test systems for ADAMTS13 measurement exist, long turn-around times hamper the usability in daily practice. We performed a method comparison study for two commercially available ADAMTS13 assays and evaluated the agreement between the fully-automated rapid turn-over HemosIL AcuStar ADAMTS13 Activity assay and the manually performed TECHNOZYM ADAMTS-13 Activity assay. Twenty-four paired test samples derived from 10 consecutively recruited patients (n = 8, acquired TTP; n = 1, atypical hemolytic uremic syndrome; n = 1, control), of which nine test samples were collected in case of clinically apparent TTP and 13 samples were collected from TTP patients in clinical remission were included. Overall correlation between the TECHNOZYM and AcuStar assay was good with a Pearson R of 0.93 (p < 0.001). Agreement between the assays assessed with the Passing–Bablok analysis showed high agreement with an Intercept of  − 2.56 (95% confidence interval [CI], − 5.07 to  − 0.86) and Slope of 1.04 (95% CI 0.84–1.17). The absolute mean bias was 2.54% (standard difference [SD], 6.38%; 95% CI to 10.0–15.05%). Intra-method reliability was high with an absolute mean bias of − 0.13% (SD 3.21%; 95% CI to 6.42–6.16%). The observer agreement for categorial thresholds (> or < 10% ADAMTS3 activity) was kappa = 0.82 (95% CI 0.59–1.0). Conclusively, overall agreement between the testing methods was sufficient and we support previously published data suggesting the AcuStar assay being a valuable and accurate tool for ADAMTS13 activity testing and TTP diagnostics.

scholarly journals Lesion measurement on a combined “all-in-one” window for chest CT: effect on intra- and interobserver variability

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Annemiek Snoeckx ◽  
Jeroen Cant ◽  
Caro Franck ◽  
Elisa Luyckx ◽  
Ken Carpentier ◽  
...  
Keyword(s):  
Interobserver Agreement ◽  
Interobserver Variability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Lesion Size ◽  
Processing Technique ◽  
Observer Agreement ◽  
Image Processing Technique ◽  
Measurement Variability ◽  
Intraclass Correlation Coefficients

Abstract Purpose A newly developed image processing technique fuses conventional windows into a single ‘All-In-One’ (AIO) window. This study aims to evaluate variability of CT measurement of lesions in thoracic oncology patients on this novel AIO-window. Methods Six radiologists with different levels of expertise measured 368 lesions of various size, origin and sharpness. All lesions were measured twice on the AIO-window and twice on the conventional window settings. Intraclass correlation coefficients and Bland-Altman plots were used to assess intra- and interobserver variability. Results Overall intra-observer agreement for lesion diameters on the AIO-window and conventional window settings was 0.986 (95% Confidence interval (CI): 0.983–0.989) and 0.991 (95% CI 0.989–0.993) respectively. For interobserver agreement this was 0.982 (95% CI 0.979–0.985) (AIO) and 0.979 (95% CI 0.957–0.982) (conventional). For both the AIO and conventional windows, intra- and interobserver agreement were dependent on size, sharpness and reader experience. Measurement variability decreased with increasing lesion size. Regarding sharpness, inter- and intra-observer agreement ranged from 0.986–0.989 (AIO) and 0.985–0.992 (conventional) for well-defined lesions and from 0.978–0.983 (AIO) and 0.974–0.991 (conventional) for ill-defined lesions. Conclusions Lesion diameters were consistently smaller on the AIO-window compared to conventional window settings. Overall intra- and interobserver variability rates were similar for the AIO-window and conventional window settings. We conclude that the AIO-window offers a reliable and reproducible alternative for measurement of thoracic lesions.

Patellotrochlea Index in Normal Healthy Knees

2020 ◽  
Author(s):  
Simon Middleton ◽  
Stefan Bajada ◽  
Roy Powell ◽  
Adam Nelson ◽  
Vipul Mandalia
Keyword(s):  
Healthy Volunteers ◽  
Intraclass Correlation ◽  
Mean Value ◽  
Patella Height ◽  
Asymptomatic Volunteers ◽  
Logical Method ◽  
Healthy Knee ◽  
Mri Scans ◽  
The Mean ◽  
Magnetic Resonance Imaging Mri

AbstractPatella alta is a common and significant abnormality responsible for many patellofemoral joint-related conditions. Many methods of patella height measurements are described; however, patellotrochear index (PTI) is the most logical method as it measures the direct relation between patella and trochlea. The aim of this study is to investigate PTI in normal healthy asymptomatic volunteers to understand the patellofemoral relation in normal knees. Twenty-five healthy volunteers underwent magnetic resonance imaging (MRI) scans of both knees. Two observers independently measured PTI on two different occasions at 6-week interval. Statistical analysis was performed to identify intra- and interobserver correlation between two observers and the mean value of PTI. Agreement analysis was performed according to Bland and Altman. Comparisons of means were made using paired t-tests. The mean age of 25 healthy volunteers was 21.28 years (19–23) with a male:female ratio of 14:11. The overall mean PTI value of all observations was 36.8% and pooled standard deviation (SD) 11.5%. Intraclass correlation (ICC) testing showed “good” interobserver ICC between two observers for PTI for both first (0.80) and second (0.84) set of measurements. There was “excellent” intraobserver correlation for two sets of measurements of PTI made by each first (0.96) and second (0.91) observer. Intraobserver repeatability for PTI was ± 0.07 and ± 0.1, respectively, for the first and second observer. Interobserver repeatability for PTI was ± 0.159 and ± 0.133, respectively, for the first and second set of measurements. Analysis of individual measurements of patella and trochlear articular cartilage revealed that the largest repeatability values were for trochlea measurements. The study reports that the average PTI in asymptomatic healthy knee utilizing current clinical MRI scanning conditions is 36.8%. This provides surgeons with a gold standard normal PTI value, which can serve as a target value in clinical diagnosis as well as surgical correction of patella height. There is good to excellent intra- and interobserver correlation with limited variability in assessing patella height using PTI on MRI scan.

Adaptation of the Connected Speech Test: Rerecording and Passage Equivalency

2020 ◽  
Vol 29 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Hasan K. Saleh ◽  
Paula Folkeard ◽  
Ewan Macpherson ◽  
Susan Scollie
Keyword(s):  
Speech Perception ◽  
North American ◽  
First Language ◽  
Intraclass Correlation ◽  
Normal Hearing ◽  
Connected Speech ◽  
Internal Reliability ◽  
Speech Test ◽  
The Mean ◽  
Unit Standard

Purpose The original Connected Speech Test (CST; Cox et al., 1987) is a well-regarded and often utilized speech perception test. The aim of this study was to develop a new version of the CST using a neutral North American accent and to assess the use of this updated CST on participants with normal hearing. Method A female English speaker was recruited to read the original CST passages, which were recorded as the new CST stimuli. A study was designed to assess the newly recorded CST passages' equivalence and conduct normalization. The study included 19 Western University students (11 females and eight males) with normal hearing and with English as a first language. Results Raw scores for the 48 tested passages were converted to rationalized arcsine units, and average passage scores more than 1 rationalized arcsine unit standard deviation from the mean were excluded. The internal reliability of the 32 remaining passages was assessed, and the two-way random effects intraclass correlation was .944. Conclusion The aim of our study was to create new CST stimuli with a more general North American accent in order to minimize accent effects on the speech perception scores. The study resulted in 32 passages of equivalent difficulty for listeners with normal hearing.

The Effects of Mean of Visit-to-Visit Blood Pressure on Incident Brain Vascular Lesions and Functional-Cognitive Decline

2021 ◽  
pp. 1-12
Author(s):  
Bibek Gyanwali ◽  
Celestine Xue Ting Cai ◽  
Christopher Chen ◽  
Henri Vrooman ◽  
Chuen Seng Tan ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cognitive Decline ◽  
Hippocampal Volume ◽  
Intracranial Stenosis ◽  
Vascular Lesions ◽  
Linear Regression Models ◽  
Volume Functional ◽  
Mri Scans ◽  
The Mean

Background: Cerebrovascular disease (CeVD) is an underlying cause of cognitive impairment and dementia. Hypertension is a known risk factor of CeVD, but the effects of mean of visit-to-visit blood pressure (BP) on incident CeVD and functional-cognitive decline remains unclear. Objective: To determine the association between mean of visit-to-visit BP with the incidence and progression of CeVD [white matter hyperintensities (WMH), infarcts (cortical infarcts and lacunes), cerebral microbleeds (CMBs), intracranial stenosis, and hippocampal volume] as well as functional-cognitive decline over 2 years of follow-up. Methods: 373 patients from a memory-clinic underwent BP measurements at baseline, year 1, and year 2. The mean of visit-to-visit systolic BP, diastolic BP, pulse pressure, and mean arterial pressure were calculated. Baseline and year 2 MRI scans were graded for WMH, infarcts, CMBs, intracranial stenosis, and hippocampal volume. Functional-cognitive decline was assessed using locally validated protocol. Logistic and linear regression models with odds ratios, mean difference, and 95%confidence interval were constructed to analyze associations of visit-to-visit BP on CeVD incidence and progression as well as functional-cognitive decline. Results: Higher mean of visit-to-visit diastolic BP was associated with WMH progression. Higher tertiles of diastolic BP was associated with WMH progression and incident CMBs. There was no association between mean of visit-to-visit BP measures with incident cerebral infarcts, intracranial stenosis, change in hippocampal volume, and functional-cognitive decline. Conclusion: These findings suggest the possibility of hypertension-related vascular brain damage. Careful monitoring and management of BP in elderly patients is essential to reduce the incidence and progression of CeVD.

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