C.J. Arthuis

Biparietal/transverse abdominal diameter ratio ≤ 1: potential marker for open spina bifida at 11–13‐week scan

In the first trimester of pregnancy, a biparietal diameter (BPD) below the 5th percentile is a simple marker that enables the prenatal detection of half of all cases of open spina bifida. We hypothesized that relating the BPD measurement to the transverse abdominal diameter (TAD) might be another simple and effective screening method. In this study we assessed the performance of using the BPD/TAD ratio during the first trimester of pregnancy in screening for open spina bifida.

Real-Time Monitoring of Placental Oxygenation during Maternal Hypoxia and Hyperoxygenation Using Photoacoustic Imaging

Purpose This preclinical study aimed to evaluate placental oxygenation in pregnant rats by real-time photoacoustic (PA) imaging on different days of gestation and to specify variations in placental oxygen saturation under conditions of maternal hypoxia and hyperoxygenation. Material and methods Placentas of fifteen Sprague-Dawley rats were examined on days 14, 17, and 20 of pregnancy with a PA imaging system coupled to high-resolution ultrasound imaging. Pregnant rats were successively exposed to hyperoxygenated and hypoxic conditions by changing the oxygen concentration in inhaled gas. Tissue oxygen saturation was quantitatively analyzed by real-time PA imaging in the skin and 3 regions of the placenta. All procedures were performed in accordance with applicable ethical guidelines and approved by the animal care committee. Results Maternal hypoxia was associated with significantly greater decrease in blood oxygen saturation (ΔO2 Saturation) in the skin (70.74% ±7.65) than in the mesometrial triangle (32.66% ±5.75) or other placental areas (labyrinth: 18.58% ± 6.61; basal zone: 13.13% ±5.72) on different days of pregnancy (P<0.001). ΔO2 Saturation did not differ significantly between the labyrinth, the basal zone, and the decidua. After the period of hypoxia, maternal hyperoxygenation led to a significant rise in oxygen saturation, which returned to its initial values in the different placental regions (P<0.001). Conclusions PA imaging enables the variation of blood oxygen saturation to be monitored in the placenta during maternal hypoxia or hyperoxygenation. This first preclinical study suggests that the placenta plays an important role in protecting the fetus against maternal hypoxia.

Ultrasound in labor monitoring: how to define the plane of ischial spines?

. Furthermore,we would like to add another argument in favor ofultrasound, particularly in the evaluation of descent of thefetal head.The subjective and poorly reproducible nature ofclinical examination is often highlighted in the literatureand we believe that the clinical method to assess fetal headdescent is less standardized than are ultrasound methods.Engagement of the fetal head is assessed clinically byfetal head station according to the American College ofObstetrician and Gynecologists (ACOG)

Computed tomographic study of anatomical relationship between pubic symphysis and ischial spines to improve interpretation of intrapartum translabial ultrasound

To analyze the anatomical relationship between the pubic symphysis and the ischial spines to determine reliable landmarks for the assessment of fetal head descent by intrapartum translabial ultrasound (ITU).

Engagement de la tête fœtale : ce que l’échographie nous a appris

Dans ce numéro de la revue, nous proposons un article fort intéressant intitulé « Diagnostic de l’engagement fœtal par l’échographie transpérinéale : étude préliminaire tunisienne » par Dimassi K et al. [1]. Cette étude porte sur l’évaluation échographique de la descente de la tête fœtale au cours du travail. La méthode échographique étudiée par les auteurs s’inscrit dans un domaine beaucoup plus vaste qui est celui de l’échographie en salle de naissance. Au cours du travail, l’examen clinique permet de déterminer la position du fœtus et la descente de la présentation. Au premier abord, il peut sembler étrange de vouloir déterminer la progression de la tête fœtale au moyen de l’échographie, puisqu’il suffit de faire un toucher vaginal pour obtenir cette information. Pour la variété de la présentation, l’intérêt de l’échographie est évident : celle-ci vient lever le doute que nous pouvons avoir lorsqu’il existe une bosse séro-sanguine. Un grand nombre de praticiens a déjà adopté cet outil en pratique quotidienne [2]. Mais qu’en est-il de la descente de la tête ? Sommes-nous vraiment capables d’affirmer que la présentation est engagée sur des données échographiques ? Par ailleurs, est-ce que cela présente vraiment un intérêt ? Depuis 2005, de nombreux auteurs ont proposé des méthodes ultrasonores pour évaluer la descente céphalique. Initialement il était question d’une ou deux méthodes (l’angle de progression par échographie translabiale et la distance tête–périnée par échographie transpérinéale), mais ces cinq dernières années les chercheurs ont fait preuve de créativité en

Anatomical study of the relation between the symphysis and ischial spines by CT scan: improving the interpretation of intrapartum translabial ultrasound.

To analyze the anatomical relationship between the pubic symphysis and the ischial spines to determine reliable landmarks for the assessment of fetal head descent by intrapartum translabial ultrasound (ITU).

Comment je fais… Une maturation du col par ballonnet

uterine [1]. Dans cette situation, la maturation parballonnet transcervicalestuneoptioninteressantememesisonevaluation est encore insuffisante pour qu’on puisse larecommander [2]. Neanmoins, le declenchement par ocyto-ciques sur un col defavorable presente un risque d’echecimportant. Dans cette situation, choisir de programmerd’emblee une cesarienne est une attitude parfois excessive,surtout si les autres conditions obstetricales sont toutesfavorables et si la patiente exprime un desir importantd’accoucher par les voies naturelles.Nous

Comment je fais… un tamponnement intra-utérin au cours de l’hémorragie du post-partum

L’hemorragie du post-partum (HPP) complique environ 5 % des accouchements [1]. Des 500 mL de saignement, une prise en charge active doit etre declenchee. Le tamponnement intrauterin vient completer les mesures therapeutiques initiales (delivrance artificielle, revision uterine et perfusion d’oxytocine). Les recommandations portant sur la prise en charge de l’HPP ne definissent pas precisement la place du tamponnement intra-uterin dans la strategie therapeutique globale [2]. Ce dispositif complementaire peut etre envisage en meme temps que l’instauration de la sulprostone (Nalador), et avant l’embolisation ou les gestes chirurgicaux. Il est egalement possible d’y recourir dans l’attente des traitements invasifs. Nous decrivons la mise en place du ballonnet intra-uterin de Bakri (Cook Medical, Spencer, IN) [3] et du ballonnet de Belfort-Dildy (Glenveigh Medical, Chattanooga, TN) [4] au cours d’une HPP apres un accouchement par voie basse. Dans les deux cas, le dispositif intra-uterin doit etre positionne apres une revision uterine. Une antibioprophylaxie est alors realisee selon les recommandations de la Societe francaise d’anesthesie et de reanimation (SFAR) [5]. Le ballonnet est ensuite pose dans des conditions d’asepsie rigoureuses chez une patiente prealablement sondee. En premier lieu, le

Labor and delivery description is based on data that is no longer accessible

During labor, digital vaginal examination seems to be inaccurate in assessing the fetal head descent [1]. To remedy this situation, much scientific research has been carried out to prove the usefulness of ultrasound in the management of labor and delivery [2]. In this context, obstetrical mechanics dogmas can once again be questioned. Such advances in imaging technology have often led physicians to question the reliability of clinical examinations. It is noteworthy to point out here that vaginal digital examination has been gradually replaced by transvaginal ultrasound in order to predict preterm labor [3]. In order to consider the assessment of the fetal head descent in labor, we needed to compare these new ultrasound technologies with conventional clinical examinations. This led us to take a close and thorough look at the data that was being used to back up the clinical examinations. However, we could not find any available evidence. This lack of transparency in the data concerning the assessment of the fetal head descent may also be applied to many other areas of obstetrics. Today, medical evidence is recorded in hundreds of journals accessible through databases such as Medline, Embase, Pascal and the Cochrane Library. Great progress has been made recently in the research transparency in requiring compliance with reporting guidelines [4]. There is no doubt that the reporting

Development of a Fluid Dynamic Model for Quantitative Contrast-Enhanced Ultrasound Imaging

Contrast-enhanced ultrasound (CEUS) is a non-invasive imaging technique extensively used for blood perfusion imaging of various organs. This modality is based on the acoustic detection of gas-filled microbubble contrast agents used as intravascular flow tracers. Recent efforts aim at quantifying parameters related to the enhancement in the vascular compartment using time-intensity curve (TIC), and at using these latter as indicators for several pathological conditions. However, this quantification is mainly hampered by two reasons: first, the quantification intrinsically solely relies on temporal intensity variation, the explicit spatial transport of the contrast agent being left out. Second, the exact relationship between the acquired US-signal and the local microbubble concentration is hardly accessible. This paper introduces the use of a fluid dynamic model for the analysis of dynamic CEUS (DCEUS), in order to circumvent the two above-mentioned limitations. A new kinetic analysis is proposed in order to quantify the velocity amplitude of the bolus arrival. The efficiency of proposed methodology is evaluated both in-vitro, for the quantitative estimation of microbubble flow rates, and in-vivo, for the classification of placental insufficiency (control versus ligature) of pregnant rats from DCEUS. Besides, for the in-vivo experimental setup, we demonstrated that the proposed approach outperforms the performance of existing TIC-based methods.