1,720,993 research outputs found
Ultrasonography diagnosis
No full textFetal growth is a dynamic process determined by a combination of genetic, intrauterine, and environmental influences. However, assessment of fetal growth with a onetime measurement is standard clinical practice, despite recognition that a single measurement can only indicate size, not growth. For this purpose, the fetal biometric measurements commonly used are biparietal diameter, head circumference, abdominal circumference, and femur length. These measurements can be combined into an estimated fetal weight using various formulae to provide a more straightforward and clinically relevant estimate of fetal growth. There are many published fetal growth charts available, and the choice of chart used also requires careful consideration as several potentially confusing terms and concepts associated with fetal size and growth are reported in the literature: fetal growth “standards,” fetal growth “references,” customized charts, and growth velocity standards. The relative merits and disadvantages of each approach are discussed, although none has so far proved to be clearly superior to the others. As for the timing of third trimester ultrasound screening for term fetal growth restriction, which is not currently recommended in most countries, recent studies of high methodological quality suggest that ultrasound assessment at 35–37 weeks performs better than at 30–32 weeks
Ecocardiografia fetale nella gravidanza gemellare
No full textLa gravidanza gemellare presenta un aumento rischio di anomalie cardiache congenite fetali. il capitolo descrive le caratteristiche epidemiologiche, le peculiarità e il monitoraggio delle gravidanze gemellari complicate da cardiopatie fetali in utero
Cervical cerclage in twin pregnancies
Full text linkPurpose To evaluate the outcomes of cervical cerclage
(CC) in twin pregnancies.
Methods Retrospective analysis of twin pregnancies
undergoing CC between January 2001 and December 2009
at our Institution. CC was offered in case of a cervical
length measurement B20 mm (ultrasound-indicated CC) or
in case of cervical dilatation with membranes at or beyond
the external cervical os (physical examination-indicated
CC). Cervicovaginal and rectal swabs were obtained preoperatively.
Perioperative antibiotics and tocolysis were
administered.
Results There were 28 cases of ultrasound-indicated and
14 of physical examination-indicated CC. Positive swab
cultures were observed in 21 % of cases. The incidence of
preterm delivery\34 weeks was 32 % [95 % confidence
interval (CI) 16–52 %] and 50 % (95 % CI 23–77 %) in
the ultrasound-indicated and physical examination-indicated
CC group, respectively. The incidence of premature
rupture of membranes \34 weeks was 21 % (95 % CI
8–41 %) and 29 % (95 % CI 8–58 %) in the ultrasoundindicated
and physical examination-indicated CC group,
respectively. Perinatal survival was 96 % (95 % CI
88–100 %) in the ultrasound-indicated CC group, and
86 % (95 % CI 67–96 %) in the physical examinationindicated
CC group.Conclusions We showed a high-risk of preterm delivery
in both groups, but with a high overall perinatal survival.
Our data stress the importance of re-evaluating the efficacy
of CC in twin pregnancies by properly designed clinical
trials, particularly if it is physical examination indicated
Cervical cerclage in twin pregnancies
No full textPurpose To evaluate the outcomes of cervical cerclage
(CC) in twin pregnancies.
Methods Retrospective analysis of twin pregnancies
undergoing CC between January 2001 and December 2009
at our Institution. CC was offered in case of a cervical
length measurement B20 mm (ultrasound-indicated CC) or
in case of cervical dilatation with membranes at or beyond
the external cervical os (physical examination-indicated
CC). Cervicovaginal and rectal swabs were obtained preoperatively.
Perioperative antibiotics and tocolysis were
administered.
Results There were 28 cases of ultrasound-indicated and
14 of physical examination-indicated CC. Positive swab
cultures were observed in 21 % of cases. The incidence of
preterm delivery\34 weeks was 32 % [95 % confidence
interval (CI) 16–52 %] and 50 % (95 % CI 23–77 %) in
the ultrasound-indicated and physical examination-indicated
CC group, respectively. The incidence of premature
rupture of membranes \34 weeks was 21 % (95 % CI
8–41 %) and 29 % (95 % CI 8–58 %) in the ultrasoundindicated
and physical examination-indicated CC group,
respectively. Perinatal survival was 96 % (95 % CI
88–100 %) in the ultrasound-indicated CC group, and
86 % (95 % CI 67–96 %) in the physical examinationindicated
CC group.Conclusions We showed a high-risk of preterm delivery
in both groups, but with a high overall perinatal survival.
Our data stress the importance of re-evaluating the efficacy
of CC in twin pregnancies by properly designed clinical
trials, particularly if it is physical examination indicated
Fetal cardiac parameters for prediction of twin-to-twin transfusion syndrome
No full textOBJECTIVES:
To assess myocardial performance index measured by conventional Doppler (MPI) and by tissue Doppler imaging (MPI') at 18 weeks' gestation in monochorionic diamniotic twins for the prediction of twin-to-twin transfusion syndrome (TTTS).
METHODS:
This was a single-center observational study of 100 uncomplicated monochorionic diamniotic twin pregnancies attending the twin pregnancy clinic at the University Hospital Spedali Civili of Brescia from 2009 to 2012. MPI and MPI' were obtained from the left (LV) and right (RV) ventricles of each twin at around 18 weeks of gestation (range, 17 + 1 to 19 + 4 weeks) and fortnightly thereafter. Cases which later developed TTTS formed the study group, and the remaining controls were subdivided into those continuing as uncomplicated pregnancies and those which later developed selective intrauterine growth restriction (sIUGR). Data were analyzed by receiver-operating characteristics curve analysis and univariate and multivariable logistic regression.
RESULTS:
Of the 100 pregnancies, 88 were controls (84 uncomplicated and four developed sIUGR) and 12 developed TTTS. RV-MPI and LV-MPI, and LV-MPI' were significantly higher in future TTTS recipients than in controls, while RV-MPI' was significantly lower in donors. RV-MPI and LV-MPI and LV-MPI' were found to be predictive indicators in pregnancies that had not yet developed TTTS. Their negative predictive values were > 90%, and their specificities > 80%. The best performing index was LV-MPI', with a sensitivity of 91.7% and specificity of 88.6%.
CONCLUSIONS:
Before diagnosis of TTTS, the cardiac function (as assessed by MPI and MPI') of the future donor twin is not grossly abnormal, but that of the recipient is abnormal. We identified cardiac indices predictive of the subsequent development of TTTS, and suggest a possible role of these indices in planning the follow-up of monochorionic diamniotic twin pregnancies
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
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