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Fetal short femur length as a minor marker for fetal aneuploidies, skeletal dysplasia and intrauterine growth restriction: risk stratification for isolated and not isolated finding in different gestational age
Full text linkIntroduction. Fetal short femur is defined by a femur length below the 5th percentile or -2 DS for the gestational age. The finding of a short femur represents a diagnostic dilemma for the various differential diagnosis. It may be associated with skeletal dysplasia, aneuploidies or genetic syndromes. In the isolated form, it may be an early sign of placental insufficiency and growth delay, or a normal variant in constitutionally small fetuses.
Aims of the study: The aim of this study was: to examine postnatal outcome of pregnancies complicated by a short femur length; to compare outcomes in pregnancies with an early diagnosis of short FL ( 25 weeks of gestation); to analyse outcome differences in isolated and non-isolated form. A secondary aim of our research was a proposal of a diagnostic algorithm as a tool to guide clinicians in the management and counselling of pregnancy with isolated and not isolated short femur length. For this purpose, a revision of current literature data on the argument was carried out.
Materials and Methods: A longitudinal prospective cohort study was conducted. All singleton pregnancies with a diagnosis of fetal femur < 5 centile were enrolled in the study. Patients were divided into two groups: patients with diagnosis of FL < 5th percentile at 14-24 weeks (group A) and at 25-40 weeks (group B). The differences in pregnancy complications and outcomes between the two groups were analysed. A comparison of the results of isolated and non-isolated forms was also carried out. For the secondary aim of our study we reviewed the literature and used meta-analytic technique to estimate accuracy of this marker in the prediction of Down Syndrome, IUGR and skeletal dysplasia. Correlation with poor perinatal outcome was also evaluated.
Results: We enrolled 147 cases of short femur length in singleton pregnancies. In 61 (41,49%) cases short femur was associated to other fetal anomalies, in 86/147 fetuses (58,5%) was classified as isolated. Abnormal fetal karyotype (27,3% vs 3.7% p: 0.02) and skeletal dysplasia (19,7% vs 3.7% p: 0.002) were more frequent in group A. Cases of multiple abnormalities was diagnosed in 9 cases in group A and in 6 cases in group B with a difference not statistically significant (13.6% vs 7.4% p < 0.193). Diagnosis of isolated short femur was more common in group B (79% vs 33,4%, p: 0.000). In group B diagnosis of IUGR was made in 44.4% vs 19.7% of group A (p:0.002). The SGA prevalence had a difference statistically significant between the two groups (7.6% vs 24.7% p:0.007). The percentage of live birth was significant lower than group B (34.8% vs 97,6%). A comparison based on presence of an isolated short femur and not isolate finding (Group 1: Isolated - Group 2 not isolated) was also carried out. Abnormal fetal karyotype and (24,6% vs 7,0% p: 0.004), skeletal dysplasia (24,6% vs 1.2% p: 0.004) were more frequent in non-isolated group. Diagnosis of IUGR and SGA was more common in isolated group (47,7% vs 13,1%, p: 0.000, 25,6% vs 4,9% p 0.001) (table 4). The percentage of live birth was significant lower in not isolated group (45.9% vs 86% p 0.00). A higher incidence of neonatal complication, postnatal surgery and neonatal death were notice in not isolated group compared to isolated (57,69% vs17.45% p 0.019; 27,92% vs 4,2% p:0.003).
Meta-analysis showed a higher incidence of short femur length in Down Syndrome fetuses (375/1326 28,2%) compared with euploid group (5809/188935, 3.07%) with an OR 5.12 (95% CI, 4.47-5.87). A higher incidence of IUGR/SGA was found in isolated short femur (455/3108, 14,6%) compared with the control group (11634/222362, 5.23%) with an OR of 4.12 (CI 95% 3.70-4.58).
Conclusions. The diagnosis of short FL is often a challenge in obstetrics. The results of our study could help clinicians in counseling these patients in presence of this ultrasound findings. The diagnosis of a non-isolated short femur length before 24 weeks of gestation is associated to poor pregnancy outcome. When a short femur arises late in gestation and in isolated form, pregnancy outcome is better in term of chromosomal abnormalities but high rate of IUGR, SGA and neonatal complication is possible
First trimester contingent screening for trisomies 21,18,13: is this model cost efficient and feasible in public health system?
No full textA new technology in the diagnosis of small ventricular septal defects
No full text[No abstract available
Coupled electrical and thermal transient conduction problems with a quadratic interpolation cell method approach
No full textThe Cell Method is an approach to the numerical calculation of fields that has been recently applied to the coupled computation of electric and thermal conduction using a linear interpolation of both the electric and temperature fields. In this paper a quadratic interpolation approach is presented. It is aimed at the achievement of an accurate field distribution computation particularly in complex domains such as biological structures. Such condition are encountered in the prediction of the thermal distribution obtained in hyperthermic treatments. Some results for a real case are presented in the paper
A 3-D Cell Method Formulation for Coupled Electric and Thermal Problems
No full textA finite formulation is presented for the solution of coupled problems of steady-state electric and transient thermal conductions in 3-D regions. The model is based on the cell method approach and takes advantage of the very agile algebraic formulations that it can provide for field theories. Dual barycentric cell complexes are used for both space and time domains, the latter inducing a Crank-Nicolson time integration scheme. An example of application is given, consisting in the simulation of a treatment for the thermal ablation of liver cancer. Comparisons are given with a commercial finite-element method program
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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