Adverse perinatal outcomes are strongly associated with degree of abnormality in uterine artery Doppler pulsatility index.

OBJECTIVES: To investigate the association between varying degrees of abnormality in the uterine artery Doppler pulsatility index (UtA-PI) and adverse perinatal outcomes. METHODS: Prospective study of 33,364 women who gave birth to singleton, non-anomalous babies in Oxford, following universal measurement of UtA-PI in mid-pregnancy. Relative risk ratios for the primary outcomes of extended perinatal mortality and live birth with severe small-for-gestational-age (SGA) were calculated by multinomial logistic regression, for early preterm birth (<34+0) and late preterm/term birth (≥34+0). The risks were also investigated for iatrogenic preterm birth or a composite adverse outcome before 34+0 weeks. RESULTS: Compared with women with normal UtA-PI, the risk of extended perinatal mortality before 34+0 weeks was higher in women with UtA-PI >90th centile (RRR 4.7, 95% CI 2.7-8.0, p<0.001), but this was not demonstrated in later births. The risk of severe SGA birth was strongly associated with abnormal UtA-PI for both early births (RRR 26.0, 95% CI 11.6-58.2, p<0.001), and later births (RRR 2.3, 95% CI 1.8-2.9, p<0.001). Women with a raised UtA-PI were more likely to undergo early iatrogenic birth (RRR 7.8, 95% CI 5.5-11.2, p<0.001). For each of the outcomes and the composite outcome, the risk increased significantly in association with the degree of abnormality, through the 90th, 90-94th, 95-99th and >99th centiles (ptrend<0.001). CONCLUSIONS: An elevated UtA-PI is a key predictor of iatrogenic preterm birth, severe SGA and perinatal loss up to 34+0 weeks. It is the 90th centile that should be used, and management should be further tailored to the degree of abnormality, as pregnancies with very raised UtA-PI measurements constitute a group at extreme risk. This article is protected by copyright. All rights reserved.

Detection of small- and large-for-gestational age using different combinations of prenatal and postnatal charts.

OBJECTIVE: To determine the extent to which the detection rate of small-for-gestational age (SGA) and large-for-gestational age (LGA) at birth is influenced by the use of different combinations of estimated-fetal-weight (EFW) and birth-weight (BW) charts. METHODS: This was a cohort study of all pregnant women with a singleton term birth receiving care in a university hospital during a 3-year period. All participants underwent a universal 36-week ultrasound scan for EFW measurement and had BW recorded at delivery. Five different reference charts were used for EFW and BW centile calculation. Two-by-two contingency tables were constructed using EFW as the screening test variable and BW as the outcome variable in order to calculate sensitivity, specificity, positive predictive value (PPV) and negative predictive value for all possible chart combinations. RESULTS: The cohort included 17 678 pregnancies. The sensitivity of EFW < 10th centile for the detection of BW < 10th centile ranged from 10.8% to 66.8% and the sensitivity of EFW < 3rd centile for the detection of BW < 3rd centile ranged from 4.1% to 66.8%, depending on the charts used. The sensitivity of EFW > 90th centile for BW > 90th centile ranged between 22.9% and 68.3%. When locally derived charts for EFW and BW were used, the sensitivity of detection of BW < 10th centile using EFW < 10th centile was 43.7% (PPV, 45.5%); for the detection of BW < 3rd centile using EFW < 3rd centile, the sensitivity was 25.6% (PPV, 26.7%) and, for the detection of BW > 90th centile using EFW > 90th centile, it was 49.6% (PPV, 49.0%). CONCLUSIONS: Different combinations of EFW and BW charts can yield vastly different detection rates (sensitivity) in the same population cohort and time period. If SGA and LGA detection rates are to be used as a meaningful performance indicator, healthcare systems should follow a clear and predefined methodology that includes explicit definitions of common reference standards. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Visual search in ADHD, ASD and ASD + ADHD: overlapping or dissociating disorders?

Recent debates in the literature discuss commonalities between Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) at multiple levels of putative causal networks. This debate requires systematic comparisons between these disorders that have been studied in isolation in the past, employing potential markers of each disorder to be investigated in tandem. The present study, choose superior local processing, typical to ASD, and increased Intra-Subject Variability (ISV), typical to ADHD, for a head-to-head comparison of the two disorders, while also considering the comorbid cases. It directly examined groups of participants aged 10-13 years with ADHD, ASD with (ASD+) or without (ASD-) comorbid ADHD and a typically developing (TD) group (total N = 85). A visual search task consisting of an array of paired words was designed. The participants needed to find the specific pair of words, where the first word in the pair was the cue word. This visual search task was selected to compare these groups on overall search performance and trial-to-trial variability of search performance (i.e., ISV). Additionally, scanpath analysis was also carried out using Recurrence Quantification Analysis (RQA) and the Multi-Match Model. Results show that only the ASD- group exhibited superior search performance; whereas, only the groups with ADHD symptoms showed increased ISV. These findings point towards a double dissociation between ASD and ADHD, and argue against an overlap between ASD and ADHD.

Collective decision-making appears more egalitarian in populations where group fission costs are higher.

Collective decision-making is predicted to be more egalitarian in conditions where the costs of group fission are higher. Here, we ask whether Trinidadian guppies (Poecilia reticulata) living in high or low predation environments, and thereby facing differential group fission costs, make collective decisions in line with this prediction. Using a classic decision-making scenario, we found that fish from high predation environments switched their positions within groups more frequently than fish from low predation environments. Because the relative positions individuals adopt in moving groups can influence their contribution towards group decisions, increased positional switching appears to support the prediction of more evenly distributed decision-making in populations where group fission costs are higher. In an agent-based model, we further identified that more frequent, asynchronous updating of individuals' positions could explain increased positional switching, as was observed in fish from high predation environments. Our results are consistent with theoretical predictions about the structure of collective decision-making and the adaptability of social decision-rules in the face of different environmental contexts.

Quality control of ultrasound for fetal biometry: results from the INTERGROWTH-21st Project.

OBJECTIVE: To assess a comprehensive package of ultrasound quality control in the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project, a large multicenter study of fetal growth. METHODS: Quality control (QC) measures were performed for 20 313 ultrasound scan images obtained prospectively from 4321 fetuses at 14-41 weeks' gestation in eight geographical locations. At the time of each ultrasound examination, three fetal biometric variables (head circumference (HC), abdominal circumference (AC) and femur length (FL)) were measured in triplicate on separately generated images. All measurements were taken in a blinded fashion. QC had two elements: (1) qualitative QC: visual assessment by sonographers at each study site of their images based on specific criteria, with 10% of images being re-assessed at the Oxford-based Ultrasound Quality Unit (compared using an adjusted kappa statistic); and (2) quantitative QC: assessment of measurement data by comparing the first, second and third measurements (intraobserver variability), remeasurement of caliper replacement in 10% (interobserver variability), both by Bland-Altman plots and plotting frequency histograms of the SD of triplicate measurements and assessing how many were above or below 2 SD of the expected distribution. The system allowed the sonographers' performances to be monitored regularly. RESULTS: A high level of agreement between self- and external scoring was demonstrated for all measurements (κ = 0.99 (95% CI, 0.98-0.99) for HC, 0.98 (95% CI, 0.97-0.99) for AC and 0.96 (95% CI, 0.95-0.98) for FL). Intraobserver 95% limits of agreement (LoA) of ultrasound measures for HC, AC and FL were ± 3.3%, ± 5.6% and ± 6.2%, respectively; the corresponding values for interobserver LoA were ± 4.4%, ± 6.0% and ± 5.6%. The SD distribution of triplicate measurements for all biometric variables showed excessive variability for three of 31 sonographers, allowing prompt identification and retraining. CONCLUSIONS: Qualitative and quantitative QC monitoring was feasible and highly reproducible in a large multicenter research study, which facilitated the production of high-quality ultrasound images. We recommend that the QC system we developed is implemented in future research studies and clinical practice. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

The use of local anesthesia to perform lower limb revascularization in the fragile patient with critical limb ischemia.

Patients with critical limb ischemia are usually compromised, frequently making administration of general or regional anesthesia problematic. We treated 3 fragile patients presenting contraindications to undertake traditional anesthetic techniques for lower limb revascularization, in whom local anesthesia with conscious sedation was used to complete the operation. An axillo-bifemoral, a unilateral axillo-femoral and a femoro-femoral bypass were performed. Procedure was uneventful in all three cases despite the coexistence of specific surgical challenges (distal anastomosis at the profunda in two cases, redo surgery and scarred groin in the third). Surgical revascularization under local anesthesia may be considered in selected high risk patients.

Ultrasound Guided Compression Versus Ultrasound Guided Thrombin Injection for the Treatment of Post-Catheterization Femoral Pseudoaneurysms: Systematic Review and Meta-Analysis of Comparative Studies.

OBJECTIVE: To compare results of ultrasound based techniques (ultrasound guided compression-(UGC) versus ultrasound guided thrombin injection (UGTI)) to treat iatrogenic post-catheterization femoral pseudoaneurysms. METHODS: The study design involved a systematic review of the literature and meta-analysis of comparative studies. The MEDLINE, CENTRAL, and OpenGray databases were searched up to October 2015. Primary outcome measure was efficacy, while other outcomes examined were safety (complication rate), duration of the procedure, length of hospitalization, and cost of methods. The random effects model was used to calculate combined overall effect sizes of pooled data. Data are presented as the odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CI). RESULTS: Two randomized control trials and 11 observational studies were included in the analysis. Overall, 786 and 318 subjects underwent UGC and UGTI respectively. The latter modality resulted in a significantly higher success rate (97.4% vs. 69.3%, OR 0.06, 95% CI 0.03-0.11) while the complication rate for both techniques was very low (0.69% vs. 0.78%, OR 1.77, 95% CI 0.40-7.88). Data regarding procedural duration and length of hospitalization were very scarce, favoring UGTI (procedural time: MD 35.53 min, 9.11-63.95, length of hospitalization MD 1.99 days, -0.31-4.29). Scarcity of data did not allow proper cost analysis, but two studies suggested that UGTI may offer reduced treatment costs. CONCLUSION: Available evidence suggests that UGTI is superior in terms of efficacy and as safe as UGC and thus should be used as the primary modality for the treatment of post-catheterization femoral pseudoaneurysms.

Reproducibility of measuring amniotic fluid index and single deepest vertical pool throughout gestation.

OBJECTIVE: The aim of this study is to assess the intraobserver and interobserver reproducibility of measurement of amniotic fluid index (AFI) and single deepest vertical pool (SDVP), also known as the maximal vertical pocket. METHODS: A total of 175 fetuses were evaluated. For each fetus, two observers acquired duplicate sets of AFI and SDVP. Measurement differences were expressed as actual and percentage values. For all comparisons, Bland-Altman plots were used to compare differences, and limits of agreement were calculated. RESULTS: Intraobserver and interobserver agreement remained fairly constant with gestation, both for AFI and SDVP. The intraobserver limits of agreement for AFI were -5.2 to 5 cm or -39% to 37%; whereas for SDVP, these were -2.6 to 2.4 cm or -52% to 48%. The interobserver limits of agreement for AFI measurement were -7.3 to 7.1 cm or -54% to 53% and for SDVP measurement were -2.5 to 2.5 cm or -51% to 52%. Intraobserver coefficient of variation for SDVP was 14% and for AFI was 19%; the interobserver coefficient was 19% for both AFI and SDVP. CONCLUSION: Limits of agreement for both methods are wide. The choice of method should be dictated by clinical considerations other than method reproducibility.

Life satisfaction of musicians with focal dystonia.

BACKGROUND: Little is known about the effects of musicians' dystonia (MD) on patients' life satisfaction. AIMS: To assess general life satisfaction in patients with MD with regard to their health and jobs, in relation to the duration and course of the condition. METHODS: We asked patients with MD and a group of healthy musicians (controls) to complete a life satisfaction questionnaire. We analysed responses from those who had to change their profession and those who did not, and we assessed life satisfaction scores in relation to the duration and the course of the condition. RESULTS: Of the 642 patients contacted, 295 responded (46%). We excluded 52 amateur musicians and analysed a sample of 243 patients with MD. We contacted an unknown number of healthy musicians and 57 responded. We found no differences in life satisfaction between patients and controls or between patients who had to change their profession and those who did not and no correlations between life satisfaction and the duration or the course of the disease. CONCLUSIONS: Musicians find a way to cope with dystonia, irrespective of the course of the disease or a change of profession. Patients should be made aware of self-regulatory mechanisms and the probability of being able to cope and be supported in selecting their goals and achieving them.

Pregnancy dating by fetal crown-rump length: a systematic review of charts.

BACKGROUND: Fetal crown-rump length (CRL) measurement by ultrasound in the first trimester is the standard method for pregnancy dating; however, a multitude of CRL equations to estimate gestational age (GA) are reported in the literature. OBJECTIVE: To evaluate the methodological quality used in studies reporting CRL equations to estimate GA using a set of predefined criteria. SEARCH STRATEGY: Searches of MEDLINE, EMBASE, and CINAHL databases, from 1948 to 31 January 2011, and secondary reference sources, were performed. SELECTION CRITERIA: Observational ultrasound studies, where the primary aim was to create equations for GA estimation using a CRL measurement. DATA COLLECTION AND ANALYSIS: Included studies were scored against predefined independently agreed methodological criteria: an overall quality score was calculated for each study. MAIN RESULTS: The searches yielded 1142 citations. Two reviewers screened the papers and independently assessed the full-text versions of 29 eligible studies. The highest potential for bias was noted in inclusion and exclusion criteria, and in maternal demographic characteristics. No studies had systematic ultrasound quality-control measures. The four studies with the highest scores (lowest risk of bias) satisfied 18 or more of the 29 criteria; these showed lower variation in GA estimation than the remaining, lower-scoring studies. This was particularly evident at the extremes of GA. AUTHOR'S CONCLUSIONS: Considerable methodological heterogeneity and limitations exist in studies reporting CRL equations for estimating GA, and these result in a wide range of estimated GAs for any given CRL; however, when studies with the highest methodological quality are used, this range is reduced.

Standardisation of crown-rump length measurement.

Correct estimation of gestational age is essential for any study of ultrasound biometry and for everyday clinical practice. However, inconsistency in pregnancy dating may occur through differences in measurement methods or errors during measurement. In the INTERGROWTH-21(st) Project, pregnancies are dated by the last menstrual period, provided that it is certain and associated with a regular menstrual cycle, and the gestational age by dates concurs with a first-trimester ultrasound crown-rump length (CRL) estimation. Hence, there was a need to standardise CRL measurement methodology across the study sites in this international, multicentre project to avoid systematic differences in dating. To achieve uniformity we undertook the following steps: the ultrasound technique was standardised by disseminating an illustrated, operating manual describing CRL plane landmarks and calliper application, and posters describing the correct acquisition technique were disseminated for quick reference. To ensure that all ultrasonographers understood the methodology, they forwarded a log-book to the INTERGROWTH-21(st) Ultrasound Coordinating Unit, containing the answers to a written test on the manual material and five images of a correctly acquired CRL. Interpretation of CRL was also standardised by ensuring that the same CRL regression formula was used across all study sites. These methods should minimise potential systematic errors in dating associated with pooling data from different health institutions, and represent a model for standardising CRL measurement in future studies.

Ultrasound methodology used to construct the fetal growth standards in the INTERGROWTH-21st Project.

A unified protocol is essential to ensure that fetal ultrasound measurements taken in multicentre research studies are accurate and reproducible. This paper describes the methodology used to take two-dimensional, ultrasound measurements in the longitudinal, fetal growth component of the INTERGROWTH-21(st) Project. These standardised methods should minimise the systematic errors associated with pooling data from different study sites. They represent a model for carrying out similar research studies in the future.

Standardisation and quality control of ultrasound measurements taken in the INTERGROWTH-21st Project.

Meticulous standardisation and ongoing monitoring of adherence to measurement protocols during data collection are essential to ensure consistency and to minimise systematic error in multicentre studies. Strict ultrasound fetal biometric measurement protocols are used in the INTERGROWTH-21(st) Project so that data of the highest quality from different centres can be compared and potentially pooled. A central Ultrasound Quality Unit (USQU) has been set up to oversee this process. After initial training and standardisation, the USQU monitors the performance of all ultrasonographers involved in the project by continuously assessing the quality of the images and the consistency of the measurements produced. Ultrasonographers are identified when they exceed preset maximum allowable differences. Corrective action is then taken in the form of retraining or simply advice regarding changes in practice. This paper describes the procedures used, which can form a model for research settings involving ultrasound measurements.

Fetal biometry: how well can offline measurements from three-dimensional volumes substitute real-time two-dimensional measurements?

OBJECTIVES: To assess the feasibility, accuracy and reproducibility of manipulating three-dimensional (3D) volume sets in order to reconstruct optimal two-dimensional (2D) planes for fetal biometry throughout gestation and compare them with those derived from real-time 2D scanning. METHODS: Sixty-five fetuses were evaluated at a gestational age of 14-41 weeks. For each fetus a duplicate set of seven standard fetal measurements was taken by an experienced operator using 2D ultrasound and then 20 intentionally suboptimal 3D volumes from different predefined angles were captured and stored. These were manipulated and measured. The time taken to complete a full scan, with both 2D and 3D ultrasound, was recorded. All measurement differences were expressed as gestational age-specific Z-scores. For all comparisons Bland-Altman plots were used and limits of agreement were calculated. The means and variances of the measurements were tested with a paired t-test and Pitman's test for differences in variance, respectively. The difference between the time taken to perform a 2D and a 3D scan was tested using the Wilcoxon signed-ranks test. RESULTS: Mean agreement between 2D and 3D ultrasound measurements was good, with no statistically significant differences (i.e. no systematic error) unless the head was facing anteroposteriorly, or the long axis of the femur was at 60-90° to the transducer. The variance (random error) for 3D measurements was similar to that for 2D measurements. Planes from some volumes could not be extracted (7% for head circumference, 9% for abdominal circumference and 11% for femur length). The median time required to perform a full fetal biometric scan was significantly higher for 3D than for 2D (3:04 min vs 1:57 min, respectively; P < 0.001). CONCLUSIONS: Fetal measurements derived from 3D volume acquisitions exhibited good agreement with those obtained by real-time 2D scanning, with no extra systematic or random error. However, they were slower to obtain, not all volumes were amenable to extraction of planes and measurements that came from a head facing anteroposteriorly or that were obtained with the long axis of the femur at 60-90° to the transducer were systematically smaller.

Systematic review of methodology used in ultrasound studies aimed at creating charts of fetal size.

BACKGROUND: Reliable ultrasound charts are necessary for the prenatal assessment of fetal size, yet there is a wide variation of methodologies for the creation of such charts. OBJECTIVE: To evaluate the methodological quality of studies of fetal biometry using a set of predefined quality criteria of study design, statistical analysis and reporting methods. SEARCH STRATEGY: Electronic searches in MEDLINE, EMBASE and CINAHL, and references of retrieved articles. SELECTION CRITERIA: Observational studies whose primary aim was to create ultrasound size charts for bi-parietal diameter, head circumference, abdominal circumference and femur length in fetuses from singleton pregnancies. DATA COLLECTION AND ANALYSIS: Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was given to each study. Multiple regression analysis between quality scores and study characteristics was performed. MAIN RESULTS: Eighty-three studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'Inclusion/exclusion criteria', as none of the studies defined a rigorous set of antenatal or fetal conditions which should be excluded from analysis; 'Ultrasound quality control measures', as no study demonstrated a comprehensive quality assurance strategy; and 'Sample size calculation', which was apparent in six studies only. On multiple regression analysis, there was a positive correlation between quality scores and year of publication: quality has improved with time, yet considerable heterogeneity in study methodology is still observed today. CONCLUSIONS: There is considerable methodological heterogeneity in studies of fetal biometry. Standardisation of methodologies is necessary in order to make correct interpretations and comparisons between different charts. A checklist of recommended methodologies is proposed.

Intra- and interobserver variability in fetal ultrasound measurements.

OBJECTIVE: To assess intra- and interobserver variability of fetal biometry measurements throughout pregnancy. METHODS: A total of 175 scans (of 140 fetuses) were prospectively performed at 14-41 weeks of gestation ensuring an even distribution throughout gestation. From among three experienced sonographers, a pair of observers independently acquired a duplicate set of seven standard measurements for each fetus. Differences between and within observers were expressed in measurement units (mm), as a percentage of fetal dimensions and as gestational age-specific Z-scores. For all comparisons, Bland-Altman plots were used to quantify limits of agreement. RESULTS: When using measurement units (mm) to express differences, both intra- and interobserver variability increased with gestational age. However, when measurement of variability took into account the increasing fetal size and was expressed as a percentage or Z-score, it remained constant throughout gestation. When expressed as a percentage or Z-score, the 95% limits of agreement for intraobserver difference for head circumference (HC) were ± 3.0% or 0.67; they were ± 5.3% or 0.90 and ± 6.6% or 0.94 for abdominal circumference (AC) and femur length (FL), respectively. The corresponding values for interobserver differences were ± 4.9% or 0.99 for HC, ± 8.8% or 1.35 for AC and ± 11.1% or 1.43 for FL. CONCLUSIONS: Although intra- and interobserver variability increases with advancing gestation when expressed in millimeters, both are constant as a percentage of the fetal dimensions or when reported as a Z-score. Thus, measurement variability should be considered when interpreting fetal growth rates.