Interobserver Repeatability Research Articles

Range of motion in the talo-navicular and the calcaneo-cuboid joints evaluated by ultrasound during clubfoot treatment with normal references up to the age of four years.

:PurposePrevious ultrasound studies of clubfeet have mainly focused on the first year of life. The purpose of this study was to improve the evaluation of the talo-navicular and calcaneo-cuboid joints by adding new variables, evaluating the repeatability of ultrasound measurements for normal feet and clubfeet and establishing values for normal feet up to four years of age.MethodsA control group of 105 children divided into ten age groups, and 71 clubfeet in 46 children were examined. Four new variables were introduced: medial malleolus–Talar head–Navicular distance, medial tangent of the talus to the medial border of the navicular distance, the angle between the longitudinal axis of the talus and a line from the centre of the talar head to the medial corner of the navicular, the angle between the lateral borders of the calcaneus and the cuboid. The mobility in the talo-navicular and the calcaneo-cuboid joints was assessed by comparing measurements with the foot in adduction and abduction.ResultsThe variables could be assessed with fair to very good intra- and inter-observer repeatability (intraclass correlation coefficient > 0.8 and ≥ 0.6, respectively), with a few exceptions. There was less movement in talo-navicular and calcaneo-cuboid joints in clubfeet than in controls.ConclusionMorphology of normal feet and clubfeet, as well as mobility in the talo-navicular and calcaneo-cuboid joints, can be assessed by ultrasound with a fair to very good reliability from birth to the age of four years.Level of Evidence:III

Repeatability of central corneal thickness measurements of donor corneas in preservation chamber using Fourier-domain anterior segment optical coherence tomography.

To evaluate the repeatability of central corneal thickness (CCT) measurements in donor corneas using optical coherence tomography (OCT, RTVue-Optovue, Inc., Fremont, CA). Consecutive corneas were measured by a single observer using the RTVue. All corneas were preserved in the Transend chamber and Life4°C media (Numedis, Inc., Isanti, MN/USA) and stored at 4°C. The repeatability was evaluated using a pooled within-subject standard deviation (SD), coefficient of variation (CoV), and intraclass correlation coefficient (ICC). To investigate inter-observer repeatability, a second observer independently measured the CCT for each image scan. CCT was measured in 32 eyes from 18 donors. Measurements were independently repeated by a second observer. The corneas had a mean CCT of 490.99μm ± 65.95 (381-642) as measured by Observer 1. For observer 1, the SD value for the CCT was 2.94μm, the CoV value was 0.597%, and the ICC value was 0.998 (95% CI 0.996, 0.999). For observer 2, the SD value was 5.91μm, the CoV value was 1.21%, and the ICC value was 0.992 (95% CI 0.985, 0.996). The Kappa statistic 21.88% with a p value < 0.001. The Bland-Altman plot shows that the average CCT measurements between the two observers were within 20μm of each other. The CCT measurements of donor corneas in the preservation chamber using Fourier domain OCT is highly repeatable.

Repeatability of Three-Dimensional Computed Tomographic Volumetric Measurement of Lumbosacral Intervertebral Foramina in German Shepherd Dogs.

This article determines the repeatability of a recently reported method of volumetric measurement of the lateral intervertebral neurovascular foramina at the lumbosacral junction in German shepherd dogs. Batch files including the intervertebral neurovascular foramina were derived from previously obtained computed tomography studies of the extended lumbosacral junction of 20 German shepherd dogs and converted into volume datasets. Three observers independently performed five measurements of the left and right lumbosacral intervertebral neurovascular foramina in each dog, using an Extended Brilliance Workstation (Phillips, The Netherlands) to generate a volume of the lumbosacral intervertebral foramina in cubic millimetres, as described by Worth and colleagues in 2017. The inter-observer repeatability of the mean of the five-volume measurements (40 foramina) was assessed using the Bland-Altman limits of agreement method. One observer, blinded to the previous measurements, repeated the volumetric analysis on 20 lumbosacral intervertebral foramina for an assessment of intra-observer repeatability using the same statistical methods. This method of volumetric analysis showed good intra- and inter-observer repeatability with 95% of paired comparisons falling within two standard deviations of the mean difference between them. This method of measuring the volume of the lumbosacral intervertebral neurovascular foramina is repeatedly reliable and may be a useful tool when testing the effects of motion and disease on the lumbosacral junction, and could help guide surgical intervention when foraminal narrowing is implicated in the clinical signs.

Validation of Novel Metrics from the Accommodative Dynamic Profile.

Objective and subjective methods of assessing time taken for accommodative change (ToAC) include accommodative dynamics (AD) and accommodative facility (AF). This study investigates the validity of novel metrics derived from the AD-profile and explores their relationship with AF. AD were assessed using a modified open-field autorefractor in 43 healthy adults. Non-linear regression curves were fitted to the data to derive: latency-of-accommodation (nLoA) and -disaccomodation (nLoD), Time-for-accommodation (ToA) and -disaccommodation (ToD), and objective-ToAC (oToAC). Latencies were also calculated through visual inspection of the AD data as in previous studies (pLoA and pLoD). AF was used to assess subjective-ToAC. Statistical analysis explored the relationships between the AD-metrics and AF. Subjects were assessed on three visits to examine intra- and inter-observer repeatability. nLoA and nLoD were greater than pLoA (p = 0.001) and pLoD (p = 0.004) respectively. nLoA and nLoD also demonstrated greater intra- and inter-observer repeatability than pLoA and pLoD. AF demonstrated a moderate, inverse correlation with ToA (p = 0.02), ToD (p = 0.007), and oToAC (p = 0.007). ToD was the single best accommodative predictor of AF (p = 0.011). The novel method for deriving latency was more repeatable, but not interchangeable with the techniques used in previous studies. ToD was the most repeatable metric with the greatest association with AF.

Validation of a windowing protocol for accurate in vivo tooth segmentation using i-CAT cone beam computed tomography.

Validation of three-dimensional (3D) reconstructions of full dental arches with crowns and roots based on cone beam computed tomography (CBCT) imaging represents a key issue in 3D digital dentistry. The aim of the study was to search for the most accurate in vivo windowing-based manual tooth segmentation using CBCT. The null hypothesis was that all applied windowing protocols were equivalent in terms of in vivo tooth volume measurement using CBCT. This retrospective study was based on preoperative CBCT images from patients who underwent further tooth extractions for reasons independent of this study. Written informed consent was obtained from all the participants, and the study was approved by the Ethics Committee of Cliniques Universitaires Saint Luc (Brussels, Belgium). The radiological protocol was I-CAT CBCT, 0.3 mm slice thickness, 8 cm × 16 cm field of view, 120 kVp, and 18 mAs. A total of 36 teeth were extracted from 14 patients between the ages of 18 and 68 years. Using 3D Slicer software, segmentations were performed twice by 2 independent observers, with a 1-month time period between the 2 segmentations to study intraand inter-observer repeatability and reproducibility. Four windowing protocols (level/window) were applied: 1. 1131/1858, 2. 2224/4095, 3. 1131/4095, and 4. AUTO, an automatic protocol provided by default by the software. A total of 576 segmentations were performed. Tooth volumes were automatically calculated using the software. To compare the volumes obtained from CBCT segmentations with a gold-standard method, we laser-scanned the extracted teeth. Excellent intraand inter-observer intraclass correlations were found for all of the protocols used. The best windowing protocol was 1131/1858 for both observers. Tooth volumes were obtained by manual segmentation of the CBCT images and using windowing protocol 1131/1858. No significantly different tooth volumes were found by laser scanning. Our null hypothesis was rejected. Only windowing protocol 1131/1858 allowed for significantly closer 3D in vivo segmentation of a tooth compared to I-CAT CBCT, with excellent intra-observer repeatability and inter-observer reproducibility.

Preoperative prediction of deep myometrial invasion and tumor grade for stage I endometrioid adenocarcinoma: a simple method of measurement on DWI.

To explore the utility of the tumor area ratio (TAR) for predicting deep myometrial invasion and tumor grade in stage I endometrioid adenocarcinoma (EEA). We retrospectively evaluated 86 patients with International Federation of Gynecology and Obstetrics (FIGO) stage I EEA. All patients underwent unenhanced contrast MRI and diffusion-weighted imaging (DWI) procedures. The volume and maximum area of the tumor and uterus were obtained, and the tumor volume ratio (TVR) and TAR were calculated. The Kruskal-Wallis test and Mann-Whitney U test were used to compare the differences in indexes (TVR and TAR) between the different tumor grades and between superficial and deep myometrial invasion. The TVR and TAR values for deep myometrial invasion and high-grade EEA tumors were significantly higher than the values for superficial myometrial invasion and low-grade tumors (all p = 0.000). According to the receiver-operating characteristic (ROC) curve, the area under the curve (AUC) was significantly higher for TAR than for TVR for tumors with deep myometrial invasion (0.936 vs. 0.844, p = 0.045). However, no significant differences in the AUCs for TVR and TAR were observed between high- and low-grade tumors (0.865 vs. 0.863, p = 0.956). A TAR ≥ 34.6% predicted deep myometrial invasion in EEA with a sensitivity, specificity, and accuracy of 85.0%, 84.8%, and 86.0%, respectively. A TAR ≥ 38.9% predicted high-grade tumors with a sensitivity, specificity, and accuracy of 83.3%, 81.1%, and 82.6%, respectively. TAR is useful for predicting deep myometrial invasion and high-grade stage I EEA KEY POINTS: • TAR is useful for predicting risk factors for EEA. • TAR is easy to obtain and has high accuracy. • TAR has excellent interobserver repeatability agreement (ICC range 95.1-99.6%).

Inter- and intra-observer repeatability of aortic annulus measurements on screening CT for transcatheter aortic valve replacement (TAVR): Implications for appropriate device sizing

ObjectivesTo investigate intra- and inter-observer repeatability of aortic annulus CT measurements for transcatheter aortic valve replacement (TAVR) by readers with different levels of experience and evaluate the impact of different multi-reader paradigms to improve prosthesis sizing. Methods82 TAVR screening CTAs were evaluated twice by three raters with six (R1 = radiologist), three (R2 = 3D-laboratory technician) or zero (R3 = medical student) years of experience. Results were translated into hypothetical TAVR size recommendations. Intra- and inter-observer repeatability between single readers and three different multi-reader paradigms ([A]: two readers, [B]: three readers, or [C]: two readers + an optional third reader) were evaluated. ResultsIntra-observer variability did not differ significantly (range: 50.1–67.8mm2). However, we found significant differences in mean inter-observer variance (p = 0.001). Multi-reader paradigms led to significantly increased precision (lower variability) for scenarios [B] and [C] (p = 0.03, p < 0.05). Compared to single readers, all multi-reader strategies clearly lowered the rate of discrepant device size categorization between repeated measurements (22–26% to 5–10%). ConclusionsAortic annulus CT measurements for TAVR are highly reproducible. Multi-reader strategies provide higher precision than evaluations from single readers with different levels of experience and could effectively be implemented with two readers and an optional third reader (Paradigm C) in a clinical setting.

Classification of Uterine Anomalies by 3-Dimensional Ultrasonography Using ESHRE/ESGE Criteria: Interobserver Variability.

To evaluate the interobserver repeatability of the coronal view measurements and classification of the uterine malformations (UM) according to the ESHRE/ESGE consensus by transvaginal three-dimensional ultrasound (3D-US). 89 transvaginal 3D-US volumes acquired during the last two years at Delta Ecografía in Madrid, Spain, were selected from our archive by convenience sampling. Two expert operators blinded from each other, performed post-hoc analysis using render mode and multiplanar-Volume Contrast Imaging (VCI) navigation. Uterine wall thickness at the fundus, indentation of the cavity and indentation of the fundus were measured, classified and sub-classified following the recommendations of the ESHRE/ESGE consensus. The reproducibility of interobserver measurements and classification was examined by calculating intraclass correlation coefficients (ICC) and their 95% confidence intervals (CI) and kappa statistic (k). Repeatability in the measurements: uterine wall thickness: ICC = 0.93 (95% CI, 0.90-0.96), P < 0.0001; indentation of the cavity: ICC = 0.93 (95% CI, 0.86-0.96), P < 0.0001; indentation of the fundus: ICC = 0.93 (95% CI, 0.90-0.96), P < 0.0001. Level of agreement in the classification: overall (U0, U1, U2, U3, U4, U5): k = 0.73 (95% CI, 0.61-0.84), P > 0.0001; U2 (U2a, U2b): k = 0.56 (95% CI, 0.31-0.80), P < 0.001 (0.78 observed agreement compared to 0.49 expected); U3 (U3a, U3b, U3c): k = 0.69 (95% CI, 0.16-1.00), P < 0.05 (0.85 observed agreement compared to 0.53 expected); U4 (U4a, U4b): k = 1.00 (95% CI, 1.00-1.00), P < 0.0001. Transvaginal 3D-US examination of the uterus allows assessment and classification of the UM by the ESHRE/ESGE criteria showing a good interobserver repeatability and reproducibility in most cases.

Analysis of diffusion tensor measurements of the human cervical spinal cord based on semiautomatic segmentation of the white and gray matter.

Segmentation of the gray and white matter (GM, WM) of the human spinal cord in MRI images as well as the analysis of spinal cord diffusivity are challenging. When appropriately segmented, diffusion tensor imaging (DTI) of the spinal cord might be beneficial in the diagnosis and prognosis of several diseases. To evaluate the applicability of a semiautomatic algorithm provided by ITK-SNAP in classification mode (CLASS) for segmenting cervical spinal cord GM, WM in MRI images and analyzing DTI parameters. Prospective. Twenty healthy volunteers. 1.5T, turbo spin echo, fast field echo, single-shot echo planar imaging. Three raters segmented the tissues by manual, CLASS, and atlas-based methods (Spinal Cord Toolbox, SCT) on T2 -weighted and DTI images. Masks were quantified by similarity and distance metrics, then analyzed for repeatability and mutual comparability. Masks created over T2 images were registered into diffusion space and fractional anisotropy (FA) values were statistically evaluated for dependency on method, rater, or tissue. STATISTICAL TESTS: t-test, analysis of variance (ANOVA), coefficient of variation, Dice coefficient, Hausdorff distance. CLASS segmentation reached better agreement with manual segmentation than did SCT (P < 0.001). Intra- and interobserver repeatability of SCT was better for GM and WM (both P < 0.001) but comparable with CLASS in entire spinal cord segmentation (P = 0.17 and P = 0.07, respectively). While FA values of whole spinal cord were not influenced by choice of segmentation method, both semiautomatic methods yielded lower FA values (P < 0.005) for GM than did the manual technique (mean differences 0.02 and 0.04 for SCT and CLASS, respectively). Repeatability of FA values for all methods was sufficient, with mostly less than 2% variance. The presented semiautomatic method in combination with the proposed approach to data registration and analyses of spinal cord diffusivity can potentially be used as an alternative to atlas-based segmentation. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1217-1227.

Repeatability of macular thickness measurements with the iVue-100 optical coherence tomographer

Background: The reliability of an instrument is dependent on its accuracy and repeatability. The iVue-100 optical coherence tomographer (OCT) is a spectral domain device that has the advantage of being able to measure both the anterior and posterior segments of the eye. But its repeatability for macular thickness measurements has not been assessed and this was the primary purpose of this study.Aim: To determine the repeatability of the iVue-100 OCT for macular thickness measurements.Settings: This study was conducted at the University of KwaZulu-Natal.Methods: Repeatability (intra-observer, inter-observer and inter-session) of the iVue-100 OCT was assessed on 50 participants selected using convenience sampling. Data were statistically analysed using Bland–Altman analysis, the intra-class correlation coefficient (ICC), coefficient of variation and the paired t-test.Results: The mean age and standard deviation for the 50 participants were 23.88 ± 6.93 years (range 18–51 years). The ICCs for intra-observer repeatability ranged between 0.940 and 0.989, whereas the coefficients of variation ranged between 0.040 and 0.084. For both inter-observer and inter-session repeatability, the t-test showed no statistically significant differences (p &gt; 0.05), and Bland–Altman analysis found the majority of the measurements to be within the 95% limits of agreement.Conclusion: Irrespective of whether repeated measurements are being taken consecutively by the same examiner, by a different observer or at a different time, the iVue-100 OCT is highly reliable in terms of repeatability which is of paramount importance in any clinical or research setting.

A repeatable geometric morphometric approach to the analysis of hand entheseal three-dimensional form.

The purpose of this study was to put forth a precise landmark-based technique for reconstructing the three-dimensional shape of human entheseal surfaces, to investigate whether the shape of human entheses is related to their size. The effects of age-at-death and bone length on entheseal shapes were also assessed. The sample comprised high-definition three-dimensional models of three right hand entheseal surfaces, which correspond to 45 male adult individuals of known age. For each enthesis, a particular landmark configuration was introduced, whose precision was tested both within and between observers. The effect of three-dimensional size, age-at-death, and bone length on shape was investigated through shape regression. The method presented high intra-observer and inter-observer repeatability. All entheses showed significant allometry, with the area of opponens pollicis demonstrating the most substantial relationship. This was particularly due to variation related to its proximal elongated ridge. The effect of age-at-death and bone length on entheses was limited. The introduced methodology can set a reliable basis for further research on the factors affecting entheseal shape. Using both size and shape, variables can provide further information on entheseal variation and its biomechanical implications. The low entheseal variation by age verifies that specimens under 50 years of age are not substantially affected by age-related changes. The lack of correlation between entheseal shape and bone length or age implies that other factors may regulate entheseal surfaces. Future research should focus on multivariate shape patterns among entheses and their association with occupation.

Two-dimensional speckle tracking echocardiography in calves: feasibility and repeatability study

ObjectivesTo assess the feasibility and repeatability of two-dimensional speckle tracking echocardiography for the evaluation of left ventricular function in healthy calves. Animals12 Holstein calves, 62 ± 11.6 days old; 75.25 ± 5.4 Kg. MethodsObservational study. Right parasternal short-axis views at papillary muscle level were recorded in standing calves and subsequently analyzed by two-dimensional speckle tracking for global and regional radial and circumferential strains and strain rates and radial displacement. Echocardiographic examinations were performed by 2 observers to evaluate intra- and interobserver repeatability and variability. ResultsTwo-dimensional speckle tracking was feasible in all calves. Automated tracking was better in systole than in diastole. Repeatability of the technique was good in calves. Systolic radial strain and strain rate peak values showed little variability compared with systolic circumferential strain and strain rate and to all diastolic measurements. Variability of the interobserver measurements was greater than the intraobserver measurements. ConclusionsTwo-dimensional speckle tracking is feasible in calves. As in other species, evaluation of systolic radial left ventricular function is more reliable than circumferential and diastolic left ventricular function.

A comparison of semi-automated volumetric vs linear measurement of small vestibular schwannomas

ObjectiveAccurate and precise measurement of vestibular schwannoma (VS) size is key to clinical management decisions. Linear measurements are used in routine clinical practice but are prone to measurement error. This study aims to compare a semi-automated volume segmentation tool against standard linear method for measuring small VS. This study also examines whether oblique tumour orientation can contribute to linear measurement error.Study designExperimental comparison of observer agreement using two measurement techniques.SettingTertiary skull base unit.ParticipantsTwenty-four patients with unilateral sporadic small (< 15 mm maximum intracranial dimension) VS imaged with 1 mm-thickness T1-weighted Gadolinium enhanced MRI.Main outcome measures(1) Intra and inter-observer intraclass correlation coefficients (ICC), repeatability coefficients (RC), and relative smallest detectable difference (%SDD). (2) Mean change in maximum linear dimension following reformatting to correct for oblique orientation of VS.ResultsIntra-observer ICC was higher for semi-automated volumetric when compared with linear measurements, 0.998 (95% CI 0.994–0.999) vs 0.936 (95% CI 0.856–0.972), p < 0.0001. Inter-observer ICC was also higher for volumetric vs linear measurements, 0.989 (95% CI 0.975–0.995) vs 0.946 (95% CI 0.880–0.976), p = 0.0045. The intra-observer %SDD was similar for volumetric and linear measurements, 9.9% vs 11.8%. However, the inter-observer %SDD was greater for volumetric than linear measurements, 20.1% vs 10.6%. Following oblique reformatting to correct tumour angulation, the mean increase in size was 1.14 mm (p = 0.04).ConclusionSemi-automated volumetric measurements are more repeatable than linear measurements when measuring small VS and should be considered for use in clinical practice. Oblique orientation of VS may contribute to linear measurement error.

Repeatability of Female Midurethral Measurement Using High-Frequency 3-Dimensional Transvaginal Ultrasonography.

Imaging assessment of the female urethra is critical for diagnosis and treatment of urinary incontinence. High-frequency 3-dimensional (3D) transvaginal ultrasonography (TVUS) is a novel technique for evaluating the female urethra. The aim of this study was to test the repeatability of 3D TVUS between examiners without prior experience with TVUS. Fifty women underwent 3D TVUS. Two examiners without prior experience analyzed the urethral volumes and measured the urethral parameters. Two-dimensional (2D) parameters included urethral sphincter length and urethral sphincter thickness; 3D parameters included urethral sphincter volume, midurethral complex volume, and inner core volume. One of the examiners repeated the evaluations 1 month later. Subsequently, the measurements were compared. The mean age of the patients ± SD was 34.1 ± 8.1 (range, 23-55) years; the mean height, weight, and body mass index were 160.44 ± 5.12 (range, 150-173) cm, 61.80 ± 13.64 (range, 45-110) kg, and 23.98 ± 4.91 (range, 17.53-39.92) kg/m2 , respectively. The results of our study showed excellent to good intraobserver repeatability (intraclass correlation coefficient [ICC], 0.75-0.87) for the evaluations of all parameters but urethral sphincter length (moderate ICC, 0.53), whereas they showed good to moderate interobserver repeatability (ICC, 0.44-0.77) for all parameters. The repeatability of 3D volumes (ICC, 0.59-0.87) tended to be better than that of 2D parameters (ICC, 0.44-0.76). The intraobserver and interobserver repeatability of high-frequency 3D TVUS measurements of the female urethra was excellent to moderate between examiners without previous experience. The repeatability of 3D measurements tended to be better than that of 2D parameters.

Improvements to Phakometry Using Bessel Beams.

The main problem with phakometry is the low visibility of the third Purkinje image. We built a phakometer using Bessel beams, which have properties of being resistant to diffraction and the potential for self-reconstruction. This instrument had lenticular images three times brighter than those of a conventional phakometer. To investigate Purkinje image brightness, accuracy, and repeatability of a "Bessel" phakometer compared with those of a conventional phakometer. Phakometers were developed with a telecentric imaging system focused at the pupil plane of the eye to capture anterior cornea, anterior lens (PIII), and posterior lens (PIV) Purkinje images. A Bessel beam was generated by a diode laser beam passing through a high-powered doublet with a central obstruction. Software was used to determine image sizes and estimate lens anterior and posterior surface radii of curvature (Ra, Rp), equivalent refractive index (RI), and equivalent power (F). The Bessel phakometer's accuracy was assessed using a model eye. Repeatability (interobserver and intraobserver) and Purkinje images brightnesses of Bessel and conventional phakometers were assessed with six participants. The lens parameters of the model eye determined by the Bessel phakometer were similar to those provided by the model eye's manufacturer with differences (manufacturer - Bessel) in Ra and Rp, RI, and F of +1.18 mm, 0.18 mm, +0.0053, and -0.55 D, respectively. The intraobserver repeatabilities for the Bessel and conventional phakometers were similar. The interobserver repeatabilities of Ra, Rp, and RI for the Bessel phakometer were almost half those (i.e., two times better) for the conventional phakometer. Brightnesses of PIII and PIV were approximately three times higher with the Bessel phakometer than with the conventional phakometer. The Bessel beam phakometer provided accurate estimates of lens parameters of a model eye and produced brighter Purkinje images and better interobserver repeatability than that of a conventional phakometer.

Intrasession repeatability of ocular anatomical measurements obtained with a multidiagnostic device in healthy eyes

BackgroundTo evaluate the intrasession repeatability of anterior chamber depth (ACD), central (CCT) and peripheral corneal thickness (PCT), white-to-white diameter (WTW), and irido-corneal angle (IA) measurements obtained with a multidiagnostic device in healthy eyes.MethodsA total of 107 eyes of 107 patients ranging in age from 23 to 65 years were examined with the VX120 system (Visionix-Luneau Technologies). Three consecutive measurements were obtained with this device to assess the intrasession repeatability of ACD, CCT, PCT at different nasal and temporal locations, WTW, and nasal and temporal IA. Data analysis included the calculation of within-subject standard deviation (Sw), intrasubject precision (1.96xSw), coefficient of variation (CV) and intraclass correlation coefficient (ICC).ResultsThe Sw and CV for ACD was 0.03 mm and 1.16%, respectively, with an ICC of 0.992. The Sw values for central and peripheral pachymetric measurements were below 9 μm, with CV of less than 1.6% and ICC of 0.976 or higher. For IA measurements, Sw values of 0.84 or lower were found, with a CV between 1 and 2%, and an ICC of more than 0.970. The Sw for WTW was 0.24 mm and the CV was 1.95%. No statistically significant correlations were found between any anatomical parameter evaluated and their Sw and CV values associated (−0.220 ≤ r ≤ 0.204, p ≥ 0.125).ConclusionsThe VX120 system is able to provide repeatable measurements of anatomical parameters in healthy eyes. Inter-observer repeatability should be evaluated in future studies.

Automation of the Fetal Right Myocardial Performance Index to Optimise Repeatability

Objectives: To compare the repeatability and degree of absolute agreement of an automated fetal right myocardial performance index (MPI) algorithm with manual measurements along with the impact of MPI observer experience on these two aspects. Methods: Prospective cross-sectional study of 65 uncomplicated singleton pregnancies from 22 to 39 weeks' gestation. Image analysis of double-waveform right MPI measurements was conducted first with a MATLAB automated MPI software and then independently by an experienced and an inexperienced observer. Intraclass correlation coefficients (ICCs) and 95% confidence intervals (95% CI) were used to evaluate manual and automated intra- and interobserver repeatability. In addition, Bland-Altman plots were used to determine the degree of absolute agreement. Results: Successful automation was performed on 63 cases (97%) showing repeatability ICCs of: 0.83 manual intraobserver; 0.77 manual interobserver; 1.00 automated. The degree of absolute agreement between manual and automated values was: inexperienced observer ICC 0.43 (95% CI 0.21-0.62); experienced observer ICC 0.76 (95% CI 0.63-0.85). Conclusion: Automation of right MPI demonstrates a superior reproducibility over manual measurements and reduces the experience required for successful analysis. This may lend a greater clinical applicability to MPI, and future studies to develop an automated universal reference range would be useful.

A preliminary study of fetal intelligent navigation echocardiography in the normal fetuses during second and third trimester

Objective To investigate the value of fetal intelligent navigation echocardiography (FINE, 5D Heart) in displaying the normal fetal heart structure during 20 to 38 weeks′ gestation. Methods Three-dimensional data of fetal heart during 20 to 38 weeks′ gestation were acquired using volume transducer prospectively. The STIC volume images were post-processed with 5D heart software by three physicians with different levels of echocardiographic examination and the quality of the section images were analyzed. The intra- and interobserver repeatability was analyzed for the qualification of section images. The correlation between the quality of image and gestational age, body mass index, the placenta position, fetal initial plane position were evaluated using univariate and multivariable logistic regression analysis. Results Two hundreds and five cases of pregnant women were included, and 9 cases were excluded.Volume data acquisition was completed in 180 pregnant women, and the image acquisition rate was 91.8%. The data were assessed twice by three observers and qualified 9 section images were gotten in 156-180 cases (degree of qualification 86.7%-100%). The screening images were satisfied in 152 cases (84.4%), dissatisfied with 28 cases (15.6%). The intra-observer agreement by three observers was absolute concord in four chamber view and abdomen/stomach view; excellent in three vessel trachea view(3VT), five chamber view, left ventricular outflow tract view and superior and inferior vena cava view; good in right ventricular outflow tract view, ductal arch view and aortic arch view. The inter-observer agreement by each of three observers was absolute concord in four chamber view and abdomen/stomach view; excellent in superior and inferior vena cava view; excellent to good in five chamber view, left ventricular outflow tract view, right ventricular outflow tract view; good in 3VT, ductal arch view and aortic arch view. In a univariate analysis, the quality of the image was associated with obesity (χ2=15.338, P=0.000), gestational age (χ2=23.356, P=0.000). Multivariable analysis showed that the obesity (OR=5.587, P=0.001) and gestational age (OR=8.843, P=0.000) were factors affecting the quality of the image. The average time spent in post-processing the images for first time by three observers was (2.77±1.39)min, and there was no significant difference among observers (P>0.05). Conclusions Fetal intelligent navigation echocardiography (FINE, 5D Heart) based on STIC volumes can successfully generate 9 standard fetal echocardiography views in 86.7%-100% of fetuses in the 2nd and 3rd trimesters. This method can simplify examination of the fetal heart and reduce operator dependency. Key words: Echocardiography; Fetal heart; Spatiotemporal image correlation; Fetal intelligent navigation echocardiography(FINE)

Comparison of anterior segment optical coherence tomography angiography systems for corneal vascularisation

AimTo newly describe a spectral-domain (SD) optical coherence tomography angiography (OCTA) for the cornea and directly compare two OCTA system scans of the same eyes with corneal vascularisation.MethodsCross-sectional, observational, comparative...

P06.05: Automation of the fetal right myocardial performance index (RMPI) to optimise repeatability

To compare the repeatability of an automated fetal right myocardial performance index (MPI) algorithm with manual measurements and to evaluate the degree of absolute agreement between values. A secondary aim is to determine the impact of MPI observer experience on these two aspects. A prospective cross-sectional study. Spectral Doppler double waveform, right MPI images were acquired, using a Voluson E8 from 65 uncomplicated singleton pregnancies at 22–39 weeks gestation. Three clearest cardiac cycles were selected from each case, by an experienced operator. Exported raw format images were analysed first with a MATLAB automated MPI software and then independently by an experienced and an inexperienced observer. Intraclass correlation coefficients (ICCs) and 95% confidence intervals (95% CI) were used to evaluate manual and automated intra- and inter-observer repeatability. Absolute agreement between the manual and corresponding automated MPI values was evaluated using ICCs, 95% CI and Bland-Altman plots. Successful automation was performed on 63 cases (97%) showing repeatability ICCs of: 0.83 for manual intra-observer; 0.77 for manual inter-observer and 1.00 for automated repeatability. The degree of absolute agreement between manual and automated values was: inexperienced observer ICC 0.43 (95% CI 0.21–0.62); experienced observer ICC 0.76 (95% CI 0.63–0.85). Right MPI may be a potentially useful tool in the early detection of cardiac dysfunction in a range of pathologies. Automation is precise, sensitive, demonstrates a superior reproducibility over manual measurements and reduces the experience required for successful analysis. This may lend a greater clinical applicability to MPI in functional fetal echocardiography, and future studies to develop a universal reference range based on automation would be useful. We aim for this, along with our Left MPI algorithm, to be made available as an open-source software application to apply to images from any ultrasound machine.