E. Quarello

Élastographie par ondes de cisaillement (shear waves) du placenta chez la babouine gestante

OBJECTIVES To evaluate tissue characteristics of the placenta by transabdominal ShearWave Elastography in pregnant baboon. MATERIALS AND METHOD For 9 months (03/2013-12/2013) two operators (EQ, GG) performed ultrasound of the placenta during pregnancy pregnant baboons station partner primatology project. The identification of the placenta was performed previously in 2D ultrasound. The elastography method was then activated. Three measurements were carried out by operator for each placenta. The intraclass correlation coefficients within and between observers were calculated for the objective assessment (elastography) of placental maturity. RESULTS During the study period, 21 pregnant baboons were included and ultrasounds were performed between 1 and 3 times each. The measurements have been carried out by two operators in 100% of cases. The intra- and inter-observer ICC for single values are respectively 0.657 - 95% CI (0.548 to 0.752) and 0.458 - 95% CI (0.167 to 0.675). The intra- and inter-observer ICC for average values are respectively 0.852 - 95% CI (0.784 to 0.901) and 0.628 - 95% CI (0.286 to 0.806). CONCLUSION The study by transabdominal ShearWave Elastography of placentas pregnant baboons is possible. The intra- and inter-operator reproducibility of this method is good using the average of three measurements. The objective study via elastography ShearWave of the degree of placental maturity seems not yet be used in clinical practice. Studies of larger cohorts are needed.

Coupe des trois vaisseaux et de la trachée en période prénatale : aspects anormaux ☆

Congenital heart disease (CG) are mostly from a low-risk population. Their screening should be based on reproducible and easy to use methods. Prenatal echocardiographic analysis is based primarily on the analysis of the four chambers and great vessels. The study of general admission pathways generalized since the 1980s is performed on an axial section while that of great vessels is performed in most countries more recently using several views and remains difficult. We review the features, under normal circumstances, of the three-vessel and tracheal view that allows via an axial section of the fetal thorax to assess at the same time the trunk of the main pulmonary artery and its branches, the convergence of the ductus arteriosus and the aortic arches, the superior vena cava, and the trachea. Furthermore, the use of color Doppler mode optimizes the information obtained by this view.

Pratiques et tendancesCoupe des trois vaisseaux et de la trachée en période prénatale : aspects anormauxPrenatal three-vessel and tracheal view: Abnormal features☆

Good knowledge of normal characteristics of prenatal three vessels and trachea view allows not only to detect, but also to identify abnormalities such as normal variants and malformations of interest to main vessels (trunk of the pulmonary artery and its branches, the aorta and the superior vena cava) and various vascular structures in the anterior-superior mediastinum. These abnormalities may be isolated or associated with other anomalies of cardiac architecture.

Comment je fais… pour m’orienter devant une anomalie des gros vaisseaux ?

Les malformations cardiaques congénitales (MCG) sont à l’origine de la majorité des décès périnatals d’origine malformative. L’échocardiographie fœtale fut initialement réalisée en raison de troubles du rythme cardiaque fœtal ou d’une histoire familiale de MCG, puis a été intégrée dans l’échographie obstétricale de dépistage dans les populations à bas risque. L’échocardiographie fœtale de dépistage reposa longtemps sur l’utilisation de la seule coupe des quatre cavités entre 18 et 23 semaines d’aménorrhée (SA) avec des sensibilités reportées dans le dépistage des MCG majeures de 4,5 à 66 % selon les séries [1,2]. Cependant, un certain nombre de malformations ne sera pas accessible lors de l’obtention de cette coupe (Tableau 1). La visualisation des voies d’éjection et des gros vaisseaux permit d’améliorer le dépistage des MCG majeures avec des sensibilités reportées comprises entre 78 et 85 % [3,4]. Bien qu’initialement réalisée par des cardiologues pédiatres et des obstétriciens particulièrement sensibilisés à l’imagerie du cœur fœtal, il a été démontré qu’il est possible d’enseigner à des personnes moins expérimentées l’obtention presque systématique des voies