Formative assessment based on an audit and feedback improves nuchal translucency ultrasound image quality

OBJECTIVES

The purpose of this work was to study the impact of an audit and feedback on the quality of routine first-trimester nuchal transparency ultrasound images.

METHODS

Eighty-eight sonographers were each sent 2 different series of 30 consecutive nuchal translucency images at a mean interval of 3 months to a dedicated, protected server for remote double-blind independent analysis based on the new Collège Français d'Echographie Foetale/Centre National de la Recherche Scientifique image-scoring method (https://www.cfef.org/evaluation/ISMCFEFCNRS.pdf). The sonographers were classified as low (score below the median) or high (score above the median) scorers for each series. Before their second evaluation, 73 of the 88 sonographers received a feedback report on their first series of images, whereas the other 15 participants received no feedback. The baseline characteristics of the participants who did and did not receive feedback were comparable.

RESULTS

Participants who received feedback increased their average score significantly, from a mean ± SD of 11.1 ± 1.3 to 13.4 ± 1.4 among low scorers (P < .00001) and from 15.1 ± 1.2 to 16.0 ± 1.4 among high scorers (P < .001), whereas no significant change was seen among participants who received no feedback (low scorers, 10.9 ± 1.5 to 12.1 ± 2.0; P = .11; high scorers, 14.7 ± 1.3 to 14.6 ± 1.3; P = .99). The proportion of satisfactory images increased by 48% among low scorers who received feedback.

CONCLUSIONS

Formative assessment based on a moderately intensive audit and feedback is feasible and effective for improving the quality of routine first-trimester nuchal transparency ultrasound images.

International comparisons of behavioral and emotional problems in preschool children: parents' reports from 24 societies

International comparisons were conducted of preschool children's behavioral and emotional problems as reported on the Child Behavior Checklist for Ages 1½-5 by parents in 24 societies (N = 19,850). Item ratings were aggregated into scores on syndromes; Diagnostic and Statistical Manual of Mental Disorders-oriented scales; a Stress Problems scale; and Internalizing, Externalizing, and Total Problems scales. Effect sizes for scale score differences among the 24 societies ranged from small to medium (3-12%). Although societies differed greatly in language, culture, and other characteristics, Total Problems scores for 18 of the 24 societies were within 7.1 points of the omnicultural mean of 33.3 (on a scale of 0-198). Gender and age differences, as well as gender and age interactions with society, were all very small (effect sizes < 1%). Across all pairs of societies, correlations between mean item ratings averaged .78, and correlations between internal consistency alphas for the scales averaged .92, indicating that the rank orders of mean item ratings and internal consistencies of scales were very similar across diverse societies.

French norms and validation of the Child Development Inventory (CDI): Inventaire du Developpement de l'Enfant (IDE)

The aim of this study was to determine the French norms and examine the validity of a parent-report inventory: the Child Development Inventory (CDI), called "Inventaire du Développement de l'Enfant (IDE)" in French. This assesses the general level of a child's development in 8 developmental domains. The norms were determined for a community sample of 1287 children, aged 15 to 72 months. The score for the CDI general development scale correlates closely with chronological age (r = .89). The intra- and interobserver (mother vs teacher) agreements were .97 and .76. The 1-year stability coefficient between the developmental quotient (DQ) values was .81. Correlation between the DQ (CDI) and the IQ of psychometric individual test was high (r = .84). The sensitivity and specificity for detecting borderline children (IQ < 86) were 84% (95% CI = 72% to 92%) and 92% (95% CI = 84% to 97%), respectively. Therefore, the French version of the CDI, like the English one, provides a useful tool for measuring children's development.

Neurodevelopmental outcome following prenatal diagnosis of an isolated anomaly of the corpus callosum

OBJECTIVES

To assess the ability of prenatal ultrasound and magnetic resonance imaging (MRI) to diagnose isolated anomalies of the corpus callosum (ACC) and to further document the long-term prognosis following diagnosis.

METHODS

This was a prospective case-control study carried out between 1999 and 2004. Diagnosis was made by a combination of ultrasound and MRI. All infants were examined by a neuropediatrician and parents consented to answer questionnaires (CDI, Ireton's Child Developmental Inventory) in 22 cases, which were matched with 44 control infants. The CDI was used to assess neurodevelopmental outcome in cases and controls. Mean DQ-CDI (development quotient calculated from CDI) values and frequencies of abnormal results were compared between groups, and a meta-analysis of previous studies was performed.

RESULTS

The diagnosis of ACC was made prenatally and confirmed postnatally in 175 cases. The diagnosis was thought to be isolated ACC in 88/175 (50%) cases. Sixty of these 88 cases (68%) underwent termination of pregnancy and one died in utero. Twenty-seven were liveborn, of which 26 were followed up for a median of 50 (range, 30-74) months. Additional anomalies were diagnosed postnatally in four (15%) of these 26 neonates. The control group was significantly better (P < 0.05) compared with the cases diagnosed prenatally with isolated ACC with respect to gross motor, fine motor, language comprehension, numbers and general development, and it was marginally better for letters (P = 0.066). Seven of 26 (27%) (95% CI, 13-46%) infants with ACC over the age of 30 months had neurodevelopmental delay, compared with only one case with borderline developmental delay among the 44 controls (P = 0.006).

CONCLUSION

Prenatal diagnosis of ACC by a combination of ultrasound and MRI is reliable. However, the isolated nature of the anomaly could only be assessed in 85% of our cases. Since counseling is provided at the time of prenatal diagnosis, our population of isolated ACC included the cases that were missed prenatally as being ACC with associated anomalies. A meta-analysis of nine studies suggests that the development of children diagnosed prenatally with isolated ACC is normal in up to 70% (CI 95%, 56-83%) of cases. This means that the prospective risk of neurodevelopmental delay for a fetus with ACC described as isolated prenatally is 27%, compared with 15% for an infant whose diagnosis of isolated ACC is confirmed postnatally.

Predicting late-onset growth abnormalities using growth velocity between trimesters

OBJECTIVES

To determine whether growth velocity parameters derived from routine prenatal ultrasound measurements at first, second and third trimester can identify normal growth at term as well as late-onset growth abnormalities.

MATERIAL AND METHODS

Longitudinal study of fetal growth in normal singleton pregnancies with three normal ultrasound examinations and delivered at term. Fetuses were classified into 3 groups (<10th percentile, 10-90th percentile, >90th percentile) based on birth weight. Multiple regression on birth weight classification was used to build up a prediction equation of fetal growth potential (FGP) based on fetal biometry and fetal growth velocity parameters between ultrasound examinations. Best cut-off value for FGP predicting growth restriction and macrosomia were defined.

RESULTS

356 pregnancies were included. Fetal biometry growth velocities between examinations were calculated for all measurements. Using best cut-off values, the estimated sensitivity, specificity and odds ratio were: 60% [44;74], 91% [89;92] and 14.55 [6.30;33.98] and 53% [36;69], 89% [88;91] and 10 [4.27;23.49] for the prediction of growth restriction and macrosomia, respectively.

DISCUSSION

Fetal growth potential can be derived and calculated from standard ultrasound measurements. It can improve identification of these fetuses at risk for late-onset growth abnormalities and their related morbidity.

Échographie de l'œsophage fœtal : aspect physiologique et application au dépistage anténatal d'une atrésie œsophagienne

The thoracic part of a fetal esophagus is generally overlooked by usual prenatal ultrasonography. However, screening it might improve the detection rate of esophageal malformations for which prenatal diagnosis remains far from accurate. In this article, we describe the technique which makes it possible to get a precise image of a fetal thoracic esophagus in its more sensitive part: between the trachea and the aorta. After describing the appearance of a healthy thoracic esophagus, we will show how this technique can be used for prenatal detection of esophagus malformations. For this purpose, we provide the case report of a prenatal diagnosis of esophagus atresia with esotracheal fistula.

Quality control of an image-scoring method for nuchal translucency ultrasonography

OBJECTIVE

The objective of the study was to describe a new image-scoring method (NISM) for the measurement of nuchal translucency and crown-rump length on ultrasound scans and to establish interreviewer reliability.

STUDY DESIGN

This NISM was based on 8 criteria on a scale of 4 levels (1-4) established on clearly defined ultrasound reference marks. Ten reviewers assessed the same images of 30 fetuses. After a short training period, the same images and those of 30 new fetuses were scored by these 10 reviewers.

RESULTS

The differences in scores among the 10 reviewers were significant for 4 of 45 pairwise comparisons before training, but no pairwise comparison was significant after training. Interreviewer variance was significantly lower after training (P = .045). The intraclass correlations before and after training were 0.75 and 0.82. For each criterion, the scores were dichotomized into 2 categories (1-2 vs 3-4). Kappa values for each criterion were substantial (0.61 to 0.80) or even almost perfect (0.81 to 1.00).

CONCLUSION

This NISM was highly reliable for the total scores and for each criterion evaluating the image of nuchal translucency and crown-rump length and provides a relevant quality control tool for ultrasound operators.

Brief report: Effect of menarcheal status and family structure on depressive symptoms and emotional/behavioural problems in young adolescent girls

The study investigated the relationship between depressive symptoms and emotional/behavioural problems in adolescent girls (N=553) aged 12-13 years, menarcheal status and family structure, and considered whether the effect of family structure was the same in the presence or absence of menses. The Children's Depression Inventory (CDI) and the Strengths and Difficulties Questionnaire (SDQ) were administered to a representative sample of adolescents. Results showed main effects of menarcheal status and family structure on SDQ scores and a significant interaction on CDI scores only. A non-intact family appeared to be a stronger risk factor for depressive symptomatology than for emotional/behavioural problems in menarcheal girls.

Psychometric Properties of the French Version of the Self-Report and Teacher Strengths and Difficulties Questionnaire (SDQ)

Abstract. This study was the first attempt at determining the psychometric properties of the French self-report and teacher Strengths and Difficulties Questionnaire (SDQ) versions. An epidemiological sample of 1,400 youths (12.8 ± 0.69 years), second-year schoolchildren (boys n = 692, girls n = 708), and their teachers completed the SDQ. The analyses assessed (1) reliability using the internal consistency and test-retest methods; (2) validity by means of homogeneity measures, factor analyses, and criterion group methods; and (3) inter-rater agreement. Cut-off scores were also determined. Gender was considered for factor and cut-off analyses. Psychometric properties were satisfactory for the total difficulties scale both for the self-report and teacher SDQs (although somewhat less so for the self-report subscales). The five-factor structure theoretically expected was confirmed for both SDQs. Scores above the 90th percentile were associated with an increase in the number of at-risk youths from two groups (school failure or referred for psychological care). The current data demonstrated that the French SDQ versions could accurately measure psychopathological symptoms in youths and be considered as screening tools whose validity would appear to be promising.

French fetal biometry: reference equations and comparison with other charts

OBJECTIVES

To construct new reference charts and equations for fetal biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL), using a large sample of fetuses examined at 15-40 weeks in France, and to compare them with previous references.

METHODS

The study data were obtained over a continuous 1-year period from a population of pregnant women undergoing ultrasound examination. Excluded were those with a known abnormal karyotype or congenital malformation, multiple pregnancies, and those with no first-trimester dating based on crown-rump length. No fetuses were excluded on the basis of abnormal biometry or birth weight. For each measurement, separate regression models were fitted to estimate both the mean and the SD at each gestational age.

RESULTS

Full biometric measurements were obtained for 19 647 fetuses. New charts and reference equations are reported for BPD, HC, AC and FL. Prediction intervals for the new reference charts were similar to those of previous ones, whereas there were some differences in predicted centiles.

CONCLUSION

We present new French reference charts and equations for fetal biometry. They can be used easily to compute centiles and Z-scores to control the quality of biometric assessments and to evaluate their performance relative to other references.

Feasibility and reproducibility of an image-scoring method for quality control of fetal biometry in the second trimester

OBJECTIVES

The need for training programs and certification processes in fetal ultrasound has become obvious. The purpose of this study was to evaluate the feasibility of a score-based quality control system for fetal biometry in the second trimester.

METHODS

Standard measurements of biparietal diameter and head circumference, abdominal circumference, and femur length at 20-24 weeks had been made by four operators using the same ultrasound machine. Twenty-five of each of the cephalic, abdominal and femoral images with the calipers in place were selected arbitrarily from each operator's ultrasound database and anonymized. These 300 images were analyzed by three experienced reviewers blinded to the operator's identity. Each image was first evaluated subjectively and then scored according to six criteria for abdominal and cephalic measurements and four criteria for femur length making a six-point score for abdominal and cephalic biometry and a four-point score for femur length. For subjective evaluation, inter-reviewer differences were analyzed using percentage agreement and adjusted kappa. For objective evaluation, a difference in scoring of one point or less among reviewers was considered good agreement. Intrareviewer variability was assessed using 40 images of each type of examination selected arbitrarily.

RESULTS

The distribution of scores was similar between reviewers. One operator obtained significantly lower scores whereas the other three had good and comparable results. There was no statistical difference in the mean score attributed by each reviewer and agreement was good in 84-90% of the cases. Intrareviewer agreement was good in 90-100% of the cases, with similar scores for each reviewer.

CONCLUSION

A quality control policy based on image scoring is feasible and allows for fair to good inter- and intrareviewer reproducibility. The potential contribution of this approach to assess the quality of routine ultrasound examinations should be tested on a larger scale.

Growth discrepancy in twins in the first trimester of pregnancy

OBJECTIVE

The prevalence and significance of intertwin growth discrepancy in the first trimester of pregnancy are controversial. The aim of this study was to refine the incidence and outcome of this discrepancy in relation to dating of the pregnancy and other biometric parameters.

METHODS

This prospective study of twin pregnancies initially evaluated at 11-14 weeks' gestation was conducted between 2001 and 2004. Differences in crown-rump length (CRL) and estimated gestational age (GA) were calculated for each twin pair and their distribution was analyzed according to chorionicity and mode of conception (spontaneous or following assisted reproductive technologies). CRL-based GA and actual GA were compared. Other biometric parameters were also compared for each twin pair. The distribution of discrepancies was analyzed according to pregnancy outcome.

RESULTS

A total of 182 twin pregnancies was included. The mean+/-SD discrepancy in CRL was 3.4+/-3.18 mm or 5.1+/-4.69% and the 95th centile was 9.8 mm or 14.3%. There was no influence of chorionicity (P=0.44), mode of conception (P=0.18) and no relation with outcome (P=0.54). In conceptions resulting from assisted technology, the measured CRL of the smaller twin was closer to the actual GA. Cephalic and abdominal biometric measurements were significantly greater in the twin with the smaller CRL (P<0.05). The two cases with a discrepancy>15 mm were affected by trisomy 18 and triploidy, respectively.

CONCLUSIONS

CRL discrepancy in twin pregnancies in the first trimester is a frequent finding. Discrepancy>95th centile indicates major growth delay of one twin, which could indicate the presence of aneuploidy. For milder degrees of discordance the CRL of the smaller fetus is a more accurate estimate of the actual GA.

The impact of choice of reference charts and equations on the assessment of fetal biometry

OBJECTIVES

The assessment of fetal biometry is usually based on the comparison of measured values with predicted values derived from reference charts or equations in a normal population. This study was undertaken to assess the impact of the choice of reference charts and to develop a Z-score-based tool that could help sonographers to choose the reference charts that best fit their practice.

METHODS

Fetal biparietal diameter, head circumference, abdominal circumference and femur diaphysis length measurements were made at 20-24 and 30-34 weeks' gestation by four experienced sonographers. All measurements were transformed into Z-scores calculated according to three prediction equations (Snijders and Nicolaides, 1994; Chitty et al., 1994 and Kurmanavicius et al., 1999). Distributions of Z-scores were compared to the expected standard normal distribution based on mean, SD and Kolmogorov-Smirnov test. Simulations were made to assess sensitivity (Se), specificity (Sp) and Youden's index (Se + Sp - 1) of each reference equation, reflecting their ability to identify fetuses with abnormal biometry in our population. The reference that best fitted our practice was determined based on these results.

RESULTS

The Z-scores of all biometric parameters were significantly different (P < 0.001) when using any of the three reference equations, and none of the Z-score distributions could be considered similar to the standard normal distribution. The number of measurements that would be considered as abnormal according to these references ranged from 2.6% to 23.6%. Se and Sp ranged from 39.59% to 67.12% and 90.14% to 99.69%, respectively.

CONCLUSION

Assessment of fetal biometry is largely dependent on the choice of reference charts. We suggest that the choice of reference charts for fetal biometry could be controlled using Z-scores in each institution and that this could be the first step towards any quality assessment policy. The method we describe for the choice of the most appropriate fetal biometry reference chart might be used for all size charts.

[Linear insertion of the atrioventricular valves without defect]

On a first anatomical series of 52 hearts of trisomic 21 fetuses, published in June 2002, we described a new minor cardiac anomaly, belonging to the atrioventricular septal defect, with a linear insertion of the atrioventricular valves without defect. We want to confirm these data, on a larger series of 213 new hearts of trisomic 21 fetuses by adding a complementary section to the standard examination; 100% of controls have shown a normal insertion with an offsetting of the atrioventricular valves. On 113 out of these 213 hearts of trisomic 21 fetuses, with a so called "normal" heart at the standard examination showing no defect, the complementary section has shown that only 37.2% of these hearts have a normal insertion, whereas 62.83% show a linear insertion, without offsetting and without any septal defect. This linear insertion has been observed in all the different types of atrioventricular septal defect as a good hallmark for trisomy 21; but, since then, they have always been described associated with a septal defect, atrial or ventricular. Our hypothesis is that the linear insertion of the atrioventricular valves without defect is the minor form of the atrioventricular septal defect spectrum, taking place between the prior described partial types of atrioventricular septal defect, in which there is always a defect (ostium primum type atrial septal defect or inflow type ventricular septal defect), and the real normal heart. A precise description of the level of the complementary section and of the anatomic peculiarities of the linear insertion of the atrioventricular valves without defect would help its screening in fetal ultrasonography.

Fetal lung volumetry using two- and three-dimensional ultrasound

OBJECTIVES

To compare methods of measuring fetal pulmonary volume and to establish nomograms of fetal pulmonary volume according to gestational age for the accurate diagnosis of pulmonary hypoplasia.

METHODS

Three methods of measuring fetal pulmonary volume in 39 normal fetuses were compared: two-dimensional (2D) ultrasound measurement assuming that the lung is a geometrical pyramid, three-dimensional (3D) ultrasound using the VOCAL rotational method, and the conventional multiplanar 3D mode. Linear regression was used to construct an equation for 3D volume calculation from 2D measurements (the re-evaluated pulmonary volume equation (RPVE)). Lung volume measurements were recorded from 622 singleton fetuses in order to construct nomograms.

RESULTS

There was no statistically significant difference between the lung volume values obtained using the two 3D modes. However, in comparison with the 2D measurements the volumes obtained were larger (mean difference = 11.99, P < 0.1 x 10(-6)). The relationship between the 2D and 3D volumes was determined using a statistical linear regression method: RPVE (mL) = 4.24 + (1.53 x 2DGPV), where 2DGPV (2D geometric pulmonary volume) = (surface area right lung base (cm2) + surface area left lung base (cm2)) x 1/3 height right lung (cm). Two nomograms were constructed, one for use with 2D and one for 3D technology.

CONCLUSION

2D pulmonary volume assessment can be used in clinical situations where fetal prognosis depends on lung volume and its growth potential. It is routinely available and easy to perform particularly when repeat measurements are required in evaluation of lung growth. We therefore propose this method as an alternative to magnetic resonance imaging or 3D ultrasound.

The use of the Strengths and Difficulties Questionnaire (SDQ) in Southern European countries

This paper reports a selection of completed or ongoing studies that have evaluated or applied the Strengths and Difficulties Questionnaire (SDQ) in five countries of Southern Europe: Italy, Spain, Portugal, Croatia, and France. In Italy, the SDQ has been used to study its concurrent validity with other norm-based instruments (Child Behavior Checklist-CBCL and Disruptive Behavior Disorder Rating Scale-DBDRS), to assess the efficacy of a behavioural school training, and as part of an epidemiological study. In Spain, the SDQ was used to analyse the association between respiratory and other behavioural problems. In Portugal and Croatia, psychometric properties of the three versions of the SDQ (parent, teacher, and self-reports) were investigated in samples of children ranging from 5 to 16 years. Past and ongoing studies in France have administered the SDQ to estimate inter-rater agreement between parents, teachers, and pupils, to carry out a large-scale epidemiological study, and to evaluate the efficacy of a parent training programme. In a second section, scale means obtained with the teacher version of the SDQ in three community-based samples of 7-8 year-old children from Italy, Portugal, and Spain are compared. The results show that, according to their teachers' ratings, Italian pupils showed less prosocial behaviour than their Spanish and Portuguese agemates, whereas the Portuguese children were rated as being more hyperactive and inattentive than comparable Italian and Spanish children. Possible causes underlying the observed differences between national SDQ means are discussed.

Comparison between siblings and twins supports a role for modifier genes in ADPKD

BACKGROUND

Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by intrafamilial variability in renal disease progression, which could result from a combination of environmental and genetic factors. Although a role for modifier genes has been evidenced in mouse models, direct evidence in ADPKD patients is lacking. The analysis of variability in affected siblings and monozygotic (MZ) twins would help evaluate the relative contribution of environment and genetic factors on renal disease progression in ADPKD.

METHODS

The difference in the age at end-stage renal disease (ESRD) and the intraclass correlation coefficient (ICC) were quantified in a large series of ADPKD siblings from western Europe and compared with the values obtained in a series of MZ ADPKD twins from the same geographic area.

RESULTS

Fifty-six sibships (including 129 patients) and nine pairs of MZ twins were included. The difference in the age at ESRD was significantly higher in siblings (6.9 +/- 6.0 years, range 2 months to 23 years) than in MZ twins (2.1 +/- 1.9 years, range 1 month to 6 years; P = 0.02). Furthermore, the intraclass correlation coefficient was significantly lower in siblings than in MZ twins (0.49 vs. 0.92, respectively; P = 0.003). The intrafamilial difference in the age at ESRD was not influenced by gender.

CONCLUSION

These data substantiate the existence of a large intrafamilial variability in renal disease progression in ADPKD siblings. The fact that the variability in siblings is in a significant excess of that found in MZ twins strongly suggests that modifier genes account for a significant part of this variability.

Predictive factors of radiation necrosis after radiosurgery for cerebral metastases

The aim of this study was to determine if the risk of radiation necrosis after radiosurgery is related to the presence of normal tissue included in the prescription volume. Between 1994 and 2001, 377 patients representing 760 lesions were treated by radiosurgery in our center with a 10-MV LINAC. The median age of the patients was 57 years (range 30-86 years), median tumor volume was 4.9 cm(3), median peripheral dose (70%) was 15.6 Gy and median dose at the isocenter was 21.6 Gy. Karnofsky index, disease control and number of lesions were the only parameters significantly influencing survival (median 8.6 months), while disease-free survival was correlated with the number of isocenters. Seven percent of the patients presented severe complications, including nine episodes of radiation necrosis. The only parameter influencing the risk of radiation necrosis was the conformity index (p = 0.001). These findings emphasize the importance of reducing falsely irradiated normal tissue during radiosurgery to prevent radiation necrosis.

Irradiation stéréotaxique de première intention des métastases cérébrales

BACKGROUND

The minimal radiosurgical dose required to control cerebral metastases remains unknown. The aim of this study was to test whether a lower peripheral dose than usually delivered could effectively control these lesions or not.

PATIENTS AND METHODS

One hundred and eighty patients presenting 356 lesions were give first-line radiosurgery between 1995 and 2001 in Pitié-Salpêtrière hospital using a 10 MV LINAC. Mean age was 59 years, sex-ratio was 1.65, mean KI was 70. The lung was the most frequent primary site (n=85), followed by melanoma (n=29), kidney (n=21), digestive tract (n=14), breast (n=11), and others (n=20). Seventy-six percent of the patients presented 1 or 2 lesions. Mean tumor Volume was 5.5 cm3. Mean peripheral dose was 14.8Gy, mean isocenter dose was 21.6Gy.

RESULTS

Median survival was 7.6 months, local control rate was 90% at 6 months, 76% at 1 Year and 70% at 2 years. Median "neurological disease free" survival was 15 months. Multivariate analysis demonstrated the influence of two parameters on survival: number of lesions (p=0.001) and KI (p=0.04). The only parameter significantly correlated with disease-free survival was the number of isocenters (p=0.005). Morbidity (grade 2 RTOG) was 7.2% with no perimortality.

CONCLUSIONS

Low peripheral doses delivered by radiosurgery may control brain metastases with the same efficacy and fewer side-effects as the doses usually reported in the literature.

Severe preeclampsia is associated with high inhibin A levels and normal leptin levels at 7 to 13 weeks into pregnancy

OBJECTIVE

The purpose of this study was to determine whether maternal serum inhibin A and leptin concentrations changed in the first trimester of pregnancy in patients in whom severe preeclampsia subsequently developed.

STUDY DESIGN

Blood samples were collected prospectively from patients during the first trimester of prenatal care. Patients in whom severe preeclampsia with no evidence of glucose intolerance or gestational diabetes mellitus subsequently developed were identified (study group, 30 patients) and matched with control subjects in a 1:2 ratio (control group, 60 patients). Inhibin A and leptin concentrations were determined in these first-trimester serum samples for both the study and control groups.

RESULTS

Leptin levels were correlated highly with body mass index in both groups but were not correlated with the subsequent onset of preeclampsia. Serum inhibin A concentrations were significantly higher in women in whom preeclampsia subsequently developed than in women in whom it did not. With a specific cutoff value, the estimated odds for severe preeclampsia were almost five times higher in women with high inhibin A concentrations than in women with normal levels (odds ratio, 4.93; 95% CI, 1.83, 13.28).

CONCLUSION

High serum inhibin A levels in the first trimester of pregnancy could be used as an early risk marker for preeclampsia.

Revisiting first-trimester fetal biometry

INTRODUCTION

Although advances in ultrasound have facilitated the diagnosis of fetal abnormalities in the first trimester, fetal biometry at this stage of pregnancy remains underused in prenatal diagnosis. We hypothesized that charts which directly correlate measurements to crown-rump length (CRL) could be more accurate than those based on gestational age (GA) derived from CRL measurement. The aim of this study was to construct CRL-based biometric charts.

METHODS

Measurements of biparietal diameter (BPD), head circumference (HC) and abdominal circumference (AC) were prospectively collected from 939 normal singleton fetuses. Charts and predictive equations were constructed from data obtained from pregnancies in which the CRL was between 45 and 84 mm and for which the outcome was normal.

RESULTS

Measurements of BPD, HC and AC from 880 fetuses who met the criteria were correlated with CRL and used to construct charts and predictive equations. The standard error of estimates using CRL was significantly lower than that using GA in all cases.

DISCUSSION

First-trimester growth charts and predictive equations based on CRL instead of GA are more accurate. They might have a role in quality control of first-trimester ultrasound examination and may help in the diagnosis of fetal conditions that involve early growth abnormalities.

Periventricular leukomalacia and mode of delivery in twins under 1500 g

BACKGROUND

The optimal mode of delivery in twin gestations remains undefined, particularly for twins weighing less than 1500 g.

OBJECTIVE

To evaluate the impact of the mode of delivery on neonatal outcome in twins below 1500 g.

MATERIALS AND METHODS

In this multicenter cohort study during 1999, 66 sets of twins born in hospital and weighing below 1500 g formed our study group. Antenatal and neonatal parameters and their relationship to mode of delivery were studied, based on a factor analysis. Analysis of covariance was used to assess the effect of the mode of delivery on postnatal factors, with antenatal parameters used as covariates.

RESULTS

Statistical analysis showed that infants delivered vaginally had significantly more periventricular leukomalacia than those children delivered by Cesarean section (p = 0.03). The estimated odds for leukomalacia were higher in the vaginal than in the Cesarean group when adjusted for covariates (OR = 4.7; 95% CI = 1.0, 25.15).

CONCLUSION

Routine Cesarean section should be recommended in twin gestations with infants weighing less than 1500 g, regardless of gestational age or fetal presentation.

Relationship between attentional performance and corpus callosum morphometry in patients with Alzheimer's disease

There has been considerable interest in cognitive deficits associated with Alzheimer's disease (AD) and relationships between these impairments and specific cortical atrophies. Two previous studies [Neuropsychologia 28 (1990) 1197; Dementia 3 (1992) 350] have found that AD patients exhibit significant impairments in the attentional ID/ED set-shifting tasks of the CANTAB battery which involved attentional shifting abilities. But, at present, no study has examined the neural bases of these abilities in AD patients. In the present study, the relationship between performances on this attentional test and morphometry of the anterior and posterior corpus callosum is examined in AD patients in the mild to moderate stages of the disease (n=30, mean age=74.1+/-4.9 years, mean MMSE score=23.9+/-2.6). A control group is constituted (n=20, mean age=73.15+/-5.5 years) for comparison of cerebral measurements. The stepwise multiple regression analysis indicates that the relative contribution for the total callosal and the anterior CC areas of the simple discrimination subtest is significantly positive whereas for the posterior callosal areas the relative contribution of the more complex subtest is significantly positive. AD patients from the subgroup "low", who failed to do the nine subtests of the attentional set-shifting tasks, exhibit smaller callosal areas than control subjects. There is no significant difference for all callosal measurements between AD patients from the subgroup "high", who completely succeeded the test, and control subjects. Our findings suggest that the anterior corpus callosum would be related to attentional shifting abilities in AD patients. Moreover, these patients with probable AD seem heterogeneous for performances in the attentional test of the CANTAB and for callosal atrophies.

Linear insertion of atrioventricular valves without septal defect: a new anatomical landmark for Down's syndrome?

Our objective was to explore whether minor anatomical abnormalities of the septal insertion of tricuspid and mitral valves could be a feature of trisomy 21 in fetuses with an otherwise normal heart. Postmortem examinations were performed in 41 fetuses affected by Down's syndrome and in 52 controls. Adjoining the standard postmortem procedure, an apex-to-base section of the crux of the heart was made on a plane corresponding to the sonographic four-chamber view. This allowed gross and histological examination of the hinge points of tricuspid and mitral leaflets, showing the usual apical displacement of the tricuspid valve in all controls. Of 41 fetuses affected by Down's syndrome, 18 had a structural heart defect. Of the 23 Down syndrome fetuses without a patent heart defect, 16 (i.e., 69% of those considered as having 'normal hearts') had nevertheless a linear insertion of atrioventricular valves at autopsy. Prospective clinical studies are required to evaluate if these postmortem findings can be transposed to the clinical setting of 2nd-trimester sonographic screening.

Teaching ultrasound-guided invasive procedures in fetal medicine: learning curves with and without an electronic guidance system

OBJECTIVE

To compare the learning curves of inexperienced junior obstetrics/gynecology registrars for ultrasound-guided invasive procedures on a training model, with and without an electronic guidance system.

STUDY DESIGN

Four junior registrars performed their first 100 procedures on a training model with a new electronic guidance system, and four other junior registrars performed their first 100 procedures on the same training model without using the guidance system. All procedures were performed using a free-hand technique. We evaluated the quality of the procedure, which we defined as the time spent with the entire needle clearly visualized on the screen over the total duration of the procedure. We constructed learning curves for the eight junior registrars for comparative analysis.

RESULTS

Quality of the procedure increased over time for all trainees. The learning curves were significantly steeper for trainees using the electronic guidance system. Trainees using the electronic guidance system performed better in the middle of their learning curve (procedures 25-75). All trainees reached the same level of quality by the end of their 100 procedures.

CONCLUSIONS

The automated electronic guidance system helps faster learning but, after 100 procedures on a training model, both groups reached the same level of quality.

Magnetic resonance imaging and cerebral volumic evaluation: comparison of four post-processing techniques

Four different MRI techniques of volumetric evaluation were applied in 10 healthy females and compared. The results have shown that not all techniques were interchangeable, but that the results of two groups of methods are not statistically different.

Carotid artery stenosis: prospective comparison of CT, three-dimensional gadolinium-enhanced MR, and conventional angiography

PURPOSE

To prospectively compare gadolinium-enhanced magnetic resonance (MR) angiography and computed tomographic (CT) angiography with digital subtraction angiography (DSA) for use in detecting atheromatous stenosis and plaque morphology at the carotid bifurcation.

MATERIALS AND METHODS

Forty-four carotid arteries (in 22 patients) were analyzed by using CT angiography, enhanced MR angiography, and DSA. CT and enhanced MR angiograms were reconstructed with maximum intensity projection and multiplanar volume reconstruction. The following four features were analyzed: degree of stenosis on the basis of North American Symptomatic Carotid Endarterectomy Trial criteria, length of stenosis, luminal surface, and presence of ulcers.

RESULTS

There was significant correlation between CT angiography, enhanced MR angiography, and DSA for degree and length of stenosis. With enhanced MR angiography and CT angiography, degree of stenosis was underestimated in two of 44 cases. No case of overestimation with CT angiography was found. Severe internal carotid artery stenoses were detected with high sensitivity and specificity: 100% and 100%, respectively, with CT angiography; 93% and 100%, respectively, with enhanced MR angiography. Luminal surface irregularities were most frequently seen at CT angiography. With CT angiography and enhanced MR angiography, more ulceration was detected than with DSA.

CONCLUSION

There was a significant correlation between CT angiography, enhanced MR angiography, and DSA in evaluation of carotid artery stenosis. Enhanced MR angiography or CT angiography can be used to adequately evaluate carotid stenosis.

Measurement of the corpus callosum using magnetic resonance imaging: analyses of methods and techniques

Since the first postmortem report of sex-related differences in the size of the human corpus callosum, a number of studies on sex differences have been published, but results conflicted. The aim of this review was not to assess the possible existence and magnitude of sex variations in the size of the corpus callosum but to analyze methodological differences in several studies using Magnetic Resonance Imaging to investigate the sexual dimorphism in the size of the corpus callosum. Methodological problems arise at several steps of the method: sampling, imagery techniques, and measurements. Moreover, the means of callosal areas obtained by the nine reported studies are significantly different. The hypothesis that methodoiogical differences could explain these differences is supported by statistical results. A common method for investigating sex-related differences in callosal morphology appears necessary to resolve the question of a real sexual dimorphism of the corpus callosum and its subregions.

Relationship between discrimination tasks of the cantab and the corpus callosum morphology in Alzheimer's disease

The relationship between performances on a simple discrimination task of the Attentional Set Shifting of the Cambridge Neuropsychological Test Auto mated Battery (CANTAB) and morphometry of the corpus callosum is examined in patients with Alzheimer's disease. Analysis showed patients with probable Alzheimer's disease are heterogeneous for the relationship between performances in the attentional test of the CANTAB and the anterior callosal atrophies. Interest in these results for clinical diagnosis of this mental disease is discussed.

Extent of tumor-brain interface: a new tool to predict evolution of malignant gliomas

OBJECT

Tumor size is one of the features commonly used in oncology to predict disease evolution. However, for most primary brain tumors it is not predictive of outcome. Taking advantage of a gene therapy trial in which recurrences of glioblastoma were targeted with suicide genes, the authors developed a new parameter: the extent of tumor-brain interface--also called surface of tumor volume (STV)--to better describe three-dimensional conformation and the relationship between tumors and the surrounding normal tissue. Correlations between the STV and the usual clinical parameters were analyzed.

METHODS

Between 1995 and 1998, 16 patients presenting with recurrent glioblastomas were enrolled in this study. Preoperative magnetic resonance images were analyzed on a separate workstation; the interface between tumor and normal brain tissue was measured on each 3-mm-thick section to assess STV. The mean STV was 29.2 cm2, and the mean tumor volume (TV) was 23.8 cm3. The STV was significantly correlated with survival (Spearman test: r = -0.54, p = 0.03), but TV was not (Spearman test: r = -0.39, p = 0.15). A separate analysis of responding and nonresponding patients showed that, as expected, STV was negatively correlated with survival among nonresponding patients (p = 0.04), but that among responding patients there was a positive tendency between STV and survival.

CONCLUSIONS

These findings indicate that STV may be a useful tool for predicting the evolution of malignant glioma. Moreover, in future gene therapy trials in which such in situ approaches are used, increasing density and improved distribution of transfer cells should be taken into consideration as an important issue for efficacy.

Fetal biometric parameters, twin type and birth weight difference. A longitudinal study

OBJECTIVE

To examine the relationship between twin type, divided by zygosity, chorionicity, and birth weight difference [more or less than 15% intertwin weight difference at delivery] on fetal biometric measurements, including biparietal diameter, transverse abdominal diameter, head and abdominal circumferences (AC) and head and abdominal areas, femur length (FL), transverse cerebellar diameter, cerebellar circumference and cerebellar area at 18, 23, 28 and 32 weeks of gestational age.

STUDY DESIGN

A prospective and longitudinal study was done on 75 twin pairs that did not present the twin-twin transfusion syndrome (150 fetuses) divided into birth weight difference group I (<15%) and group II (>/=15%). The twin pairs were divided into three groups: dizygotic, monochorionic, and dichorionic-monozygotic. In each group the differences in various ultrasound indices were evaluated in reference to discordant growth or concordant growth.

RESULTS

In our sample, there were no monozygotic twin pairs with dichorionic placentation with a birth weight difference of more than 15%. Significant associations of group and gestational age were found in dizygotic and monochorionic twins. Intrapair differences were significantly higher in group II (>/=15%) than in group I (<15%) for all fetal parameters studied except for AC, abdominal area and all cerebellar parameters. The value of these discrepancies increased according to gestational age except for FL. Significant interactions between group and zygosity type indicated that intrapair FL differences were more associated with group in monochorionic twins, whereas intrapair transverse cerebellar diameter differences were more associated with group in dizygotic twins.

CONCLUSION

Our data show that most fetal biometric parameters are associated with birth weight discordancy. Abdominal area could be a relevant marker for twins with obstetric complications. Note that this is the first research that has studied a twin sample divided by both twin type and birth weight group.

[Biometry 2000. Fetal growth charts by the French College of fetal ultrasonography and the Inserm U 155]

OBJECTIVE

The aim of Biometry 2000 was to establish reliable sonographic fetal auxology reference charts for biparietal diameter, head circumference, abdominal diameter, abdominal circumference and femur length.

DESIGN

A prospective multicentric longitudinal and transversal study was carried out.

SUBJECTS

The data of this study were obtained from 35,456 scans recorded in 10,043 women for a period of one year.

METHODS

Sonographic measurements were performed using a single method for each parameter. Twins and unknown gestational ages were not included. No exclusions were made for small-for-age, congenital malformations or any event during pregnancy. Assuming measurements have a normal distribution, centiles were calculated after polynomial regression models from mean and standard deviation according to gestational age in exact weeks from last menstrual period.

RESULTS

A total of 32,584 fetal biparietal diameters, 20,400 direct cephalic circumferences, 31,790 transverse abdominal diameters, 21,562 direct abdominal circumferences and 30,960 femur lengths were obtained. Fetal growth charts with means, standard deviations and centiles are presented.

CONCLUSION

The multicentric study, Biometry 2000, has established sonographic fetal charts derived from a large sample of scans and unselected pregnant women assuming a normal distribution.

Magnetic resonance imaging of cerebral central sulci: a study of monozygotic twins

The cerebral central sulci, seat of the sensorimotor cortex, vary anatomically in form, length and depth among individuals and present a left/right asymmetry. The purpose of this work was to measure central sulcus's lengths, at the surface and in-depth, in each hemisphere of monozygotic twins in order to evaluate the influence of environmental factors on the morphometry and asymmetry of this structure. A measurement technique on MR images of the brains using 3 D software was developed. Two operators applied this technique to measure central sulcus lengths at the surface of the brain and in-depth in each hemisphere. Besides the fact that the technique developed gave high Intraclass Correlation Coefficients (ICC) for the surface lengths (mean value 0.94), and slightly less high for the in-depth length (mean value 0.87), we found a weak (from 0.57 to 0.73 for raw data) but significant ICC between homologous sulci in pairs of twins. In addition, the ICC for asymmetry indices were not significant. Hence, if central sulcus morphometry is in part genetically influenced, these results show that nongenetic factors are nonetheless important in their development.

Statistical sulcal shape comparisons: application to the detection of genetic encoding of the central sulcus shape

Principal Component Analysis allows a quantitative description of shape variability with a restricted number of parameters (or modes) which can be used to quantify the difference between two shapes through the computation of a modal distance. A statistical test can then be applied to this set of measurements in order to detect a statistically significant difference between two groups. We have applied this methodology to highlight evidence of genetic encoding of the shape of neuroanatomical structures. To investigate genetic constraint, we studied if shapes were more similar within 10 pairs of monozygotic twins than within interpairs and compared the results with those obtained from 10 pairs of dizygotic twins. The statistical analysis was performed using a Mantel permutation test. We show, using simulations, that this statistical test applied on modal distances can detect a possible genetic encoding. When applied to real data, this study highlighted genetic constraints on the shape of the central sulcus. We found from 10 pairs of monozygotic twins that the intrapair modal distance of the central sulcus was significantly smaller than the interpair modal distance, for both the left central sulcus (Z = -2.66; P < 0.005) and the right central sulcus (Z = -2.26; P < 0.05). Genetic constraints on the definition of the central sulcus shape were confirmed by applying the same experiment to 10 pairs of normal young individuals (Z = -1.39; Z = -0.63, i.e., values not significant at the P < 0.05 level) and 10 pairs of dizygotic twins (Z = 0.47; Z = 0.03, i.e., values not significant at the P < 0.05 level).

Hemispheric asymmetry and corpus callosum morphometry: a magnetic resonance imaging study

Previous post-mortem studies (Aboitiz, F., Scheibel, A.B., Fisher, R.S., Zaidel, E., 1992. Brain Res. 598, 154-161 and Aboitiz, F., Scheibel, A.B., Zaidel, E., 1992. Brain 115, 1521-1541) have shown an inverse association between asymmetry in perisylvian areas and the size of a specific segment, the isthmus, of the corpus callosum (CC) in males. The purpose of this work was to study in vivo the association between hemispheric asymmetry and the total size of the CC in 35 right-handed subjects (16 males, 19 females; mean age 24.9 +/- 3.9). An MRI scan was performed for each subject. The area of the right (RH) and left (LH) hemispheres were measured from images in the sagittal plane and the area of the CC from images in the mid-sagittal plane. The index of hemispheric asymmetry was absolute value((LH - RH)/[(LH + RH)/2]). There was a negative correlation between the absolute value of hemispheric asymmetry and the size of the CC in males (r = -0.55, P = 0.03) but not in females (r = -0.20, P = 0.42). These findings, like those of Aboitiz et al. (Aboitiz, F., Scheibel, A.B., Zaidel, E., 1992. Brain 115, 1521-1541), suggest a sex-dependent decrease in interhemispheric connectivity with increasing hemispheric asymmetry.

Is there a negative correlation between explicit memory and hippocampal volume?

The aim of this research was to study the relationship between explicit memory and hippocampal volume. Seventy healthy adults were administered one implicit memory test and one explicit memory (EM) test and underwent magnetic resonance imaging. The major finding was a negative correlation between the EM test and the right hippocampus/brain volume ratio (t = -0.25, P = 0.03) and the left hippocampus/brain volume ratio (t = -0.27, P = 0.02). This finding is not consistent with pathologic findings, which tend to show a relationship between decrease in memory performance and hippocampal atrophy. This discrepancy is discussed.

Perinatal mortality in twin pregnancies: a 3-year analysis in Seine Saint-Denis (France)

OBJECTIVES

Our purpose was to evaluate perinatal mortality in twins and to investigate factors associated with this mortality.

STUDY DESIGN

A prospective study on the perinatal mortality was performed in the department of Seine-Saint-Denis. Out of all the perinatal deaths, we have retrospectively isolated those arising from twin pregnancies.

RESULTS

There were 54 twin pregnancies complicated with perinatal death. The perinatal mortality rate in twin pregnancy was 78.0 per 1000 twin babies delivered. Out of 86 twin deaths, 38 (44.2%) were born before 28 weeks gestation and out of 82 twin perinatal deaths, 37 (45.1%) weighed less than 1000 g. Chorionicity was recorded in 44 twin pairs: 21 (47.7%) were dichorionic and 23 (52.3%) monochorionic. Finally, out of 48 twin sets there were four (8.3%) monoamniotic pregnancies.

CONCLUSIONS

The present data show that extreme prematurity represents nearly half of perinatal mortality in twins. This study indicates also a significant proportion of monochorionic placentation among twin pregnancies with poor outcome.

How can we boost IQs of "dull children"?: A late adoption study

From 5,003 files of adopted children, 65 deprived children, defined as abused and/or neglected during infancy, were strictly selected with particular reference to two criteria: (i) They were adopted between 4 and 6 years of age, and (ii) they had an IQ <86 (mean = 77, SD = 6.3) before adoption. The average IQs of adopted children in lower and higher socioeconomic status (SES) families were 85 (SD = 17) and 98 (SD = 14.6), respectively, at adolescence (mean age = 13.5 years). The results show (i) a significant gain in IQ dependent on the SES of the adoptive families (mean = 7.7 and mean = 19.5 IQ points in low and high SES, respectively), (ii) IQs after adoption are significantly correlated with IQs before adoption, and (iii) during adolescence, verbal IQs are significantly lower than performance IQs.

Twin differences and similarities of birthweight and term in the French Romulus population

This study was performed to examine the main characteristics of the French Romulus twin population: zygosity, chorionicity, sex, term and birthweight. A sample of 104 pairs of twins was distinguished by zygosity, chorionicity and sex, and divided into concordant and discordant birthweight groups. Fifty-three % (n = 55) of the fetus pairs studied were born at "ideal term" (35-38 weeks), and 25% (n = 26) were delivered at "preterm" (28-34 weeks). The very preterm (< 28 weeks), and "postterm" (> 38 weeks) represented altogether 22% (n = 23) of the sample. Of the 104 twin pairs, 68% (n = 71) differ by less than 15% in birthweight, and 32% (n = 33) have a birthweight difference higher than 15%. In dizygotic (DZ) pairs females had more tendency to be in the discordant group (p = 0.01) while in monochorionic-monozygotic (MC-MZ) pairs males were more discordant (p = 0.07). We found a significant interaction between sex and zygosity type (p = 0.02). Males had a birthweight difference significantly weaker than that of females in dichorionic-monozygotic (DC-MZ) and DZ twins whereas it was higher than that of females in MC-MZ twins. There were no MZ twin pairs with DC placentation over than 15% birthweight difference. Log linear analysis demonstrated a three-way interaction (p < 0.05) between term type, zygosity type and hypotrophy. Our data indicate that in the group of twins born between 35 and 38 weeks' gestation the crucial question still remains unsettled on how term and birthweight are related to zygotism and/or chorionicity.

Procedure to extract a weekly pattern of performance of human reaction time

A study of reaction time in six tests (speed of simple identification, simultaneous and sequential letter identification, simultaneous and sequential stimulus word matching, and semantic verification) was carried out on 130 children aged 7 to 12 years. Subjects were tested Monday, Tuesday, Thursday, and Friday, using a cross-sectional design. The answers to each of the tests are binary in nature (Yes/No) measured by the recording of a click one of the two buttons of a microcomputer. Controlled variables were age, failure, sex, and day of test. The greatest percentage of the variance produced by the data was due to the age (typically 25%). The percentage attributable to the "day of test" (typically 5%) is hence masked by the variance due to the other factors. The method proposed herein makes it possible to isolate the percentage of the variance for the variable "day of test" alone and to provide evidence for a circaseptan effect on reaction time. It used a regressive correction on predominant variables. This effect shows performance is best on Thursday and weakest on Monday, the amplitude of the weekly rhythm being related to the task.

Are the brains of monozygotic twins similar? A three-dimensional MR study

PURPOSE

The role of genetic mechanisms and the influence of environmental events in human brain development have been difficult to evaluate. The purpose of this study was to compare the cerebral cortical morphology and midline structures of monozygotic twin pairs using MR imaging.

METHODS

Six observers, blinded to twin pairings, evaluated the 3-D renderings of the cortical surface and midline structures from MR images of seven monozygotic twin pairs. A morphometric analysis of the corpus callosum and of the distance between the anterior and posterior commissures was also performed.

RESULTS

Despite surprising anatomic differences, the brains of the twin pairs were similar enough to enable the observers to distinguish twin pairs from unrelated subjects. Five of six observers correctly identified the brains of all seven twin pairs; the remaining observer failed to make a correct match in only one of seven pairs. Three of six observers identified the midline sagittal images of the related twins in all seven pairs, and the other three identified the related midline sagittal images in five of seven pairs. The results were statistically significant.

CONCLUSION

Although the observed differences in morphologic characteristics between twins necessarily reflect nongenetic influences, the cortical patterns and midline structures of monozygotic twins probably are genetically similar.