Showing papers by "Juan Pedro Kusanovic published in 2006"

Inflammation in preterm and term labour and delivery.

Abstract: Inflammation has been implicated in the mechanisms responsible for preterm and term parturition, as well as fetal injury. Out of all of the suspected causes of preterm labour and delivery, infection and/or inflammation is the only pathological process for which both a firm causal link with preterm birth has been established and a molecular pathophysiology defined. Inflammation has also been implicated in the mechanism of spontaneous parturition at term. Most cases of histopathological inflammation and histological chorioamnionitis, both in preterm and term labour, are sub-clinical in nature. The isolation of bacteria in the amniotic fluid, known as microbial invasion of the amniotic cavity, is a pathological finding; the frequency of which is dependent upon the clinical presentation and gestational age. There is a window of time during which it may be possible to detect a 'molecular signature of inflammation' by analysis of the transcriptome before histological evidence is observed. This article reviews the role of inflammation in preterm and term parturition. It is possible that modulation of inflammation using anti-inflammatory cytokines, corticoids, antioxidants and/or other factors may complement antibiotic therapy and limit fetal injury.

Normal and abnormal transformation of the spiral arteries during pregnancy.

Abstract: This article reviews the anatomy and physiology of the uterine circulation, with emphasis on the remodeling of spiral arteries during normal pregnancy, and the timing and anatomical pathways of trophoblast invasion of the spiral arteries. We review the definitions of the placental bed and basal plate of the placenta, their relevance to the study of the physiologic transformation of the spiral arteries, as well as the methods to obtain and examine placental bed biopsy specimens. We also examine the role of the extravillous trophoblast in normal and abnormal pregnancies, and the criteria used to diagnose failure of physiologic transformation of the spiral arteries. Finally, we comment on the use of uterine artery Doppler velocimetry as a surrogate marker of chronic uteroplacental ischemia.

A role of the anti-angiogenic factor sVEGFR-1 in the 'mirror syndrome' (Ballantyne's syndrome).

Abstract: Background. ‘Mirror syndrome’ (Ballantyne's syndrome) refers to the association of fetal hydrops with placentomegaly and severe maternal edema. Preeclampsia occurs in approximately 50% of these cases. Soluble vascular endothelial growth factor receptor-1 (sVEGFR-1), an anti-angiogenic factor, has been implicated in the pathophysiology of preeclampsia (PE).Objective. The objective of this study was to determine if the maternal plasma concentration of sVEGFR-1 is elevated in patients with mirror syndrome.Study design. This case-control study included patients with uncomplicated pregnancies (n = 40) and those with mirror syndrome (n = 4) matched for gestational age. Mirror syndrome was defined as fetal hydrops and severe maternal edema. Maternal plasma sVEGFR-1 concentrations were determined using specific enzyme-linked immunosorbent assays. Immunohistochemistry of sVEGFR-1 on villous trophoblasts was also performed in samples from one patient with mirror syndrome and compared with those from a patient with ...

A novel algorithm for comprehensive fetal echocardiography using 4-dimensional ultrasonography and tomographic imaging.

Abstract: Objective Tomographic ultrasound imaging (TUI) is a new display modality that allows simultaneous visualization of up to eight parallel anatomical planes. This study was designed to determine the role of a novel algorithm combining spatiotemporal image correlation (STIC) and TUI to visualize standard fetal echocardiography planes.

Four-dimensional ultrasonography of the fetal heart using a novel Tomographic Ultrasound Imaging display

Abstract: Objective: The objective of this study was to investigate the feasibility of examining the fetal heart with Tomogra- phic Ultrasound Imaging (TUI) using four-dimensional (4D) volume datasets acquired with spatiotemporal image correlation (STIC). Material and methods: One hundred and ninety-five fetuses underwent 4D ultrasonography (US) of the fetal heart with STIC. Volume datasets were acquired with B-mode (ns195) and color Doppler imaging (CDI) (ns168), and were reviewed offline using TUI, a new dis- play modality that automatically slices 3D/4D volume datasets, providing simultaneous visualization of up to eight parallel planes in a single screen. Visualization rates for standard transverse planes used to examine the fetal heart were calculated and compared for volumes acquired with B-mode or CDI. Diagnoses by TUI were compared to postnatal diagnoses. Results: (1) The four- and five-chamber views and the three-vessel and trachea view were visualized in 97.4% (190/195), 88.2% (172/195), and 79.5% (142/195), respectively, of the volume datasets acquired with B- mode; (2) these views were visualized in 98.2% (165/ 168), 97.0% (163/168), and 83.6% (145/168), respectively, of the volume datasets acquired with CDI; (3) CDI contributed additional diagnostic information to 12.5% (21/168), 14.2% (24/168) and 10.1% (17/168) of

What does 2-dimensional imaging add to 3- and 4-dimensional obstetric ultrasonography?

Abstract: Objective The objective of this study was to determine if two-dimensional ultrasound adds diagnostic information to that provided by the examination of three-dimensional/four-dimensional (3D/4D) volume datasets alone.

Applications of 2-dimensional matrix array for 3- and 4-dimensional examination of the fetus: a pictorial essay.

Abstract: OBJECTIVES Two-dimensional (2D) matrix array is a new technology for the performance of 3-dimensional and 4-dimensional (4D) ultrasonography. In this study, we report the use of a 2D matrix array transducer for examination of fetal structures including the fetal heart. METHODS Thirty-four fetuses without abnormalities and 19 fetuses with congenital anomalies were examined with a 2D matrix array transducer (x3-1, IE-33; Philips Medical Systems, Bothell, WA). Median gestational age was 25 6/7 weeks (range, 13 0/7-40 1/7 weeks). RESULTS (1) A 360 degrees rotation and examination of selected structures was possible in the second trimester. (2) Structures were examined by maintaining the transducer in a fixed position and rotating the volume using the system trackball. (3) Dorsal and ventral parts of the hands and feet were visualized in a single volume data set, in real time, without moving the transducer. (4) Real-time en face visualization of atrioventricular valves was possible from the ventricular or atrial chambers. (5) Four-dimensional images of bones were obtained by decreasing gain settings only, with no need for cropping. (6) Four-dimensional reconstruction of vascular structures was possible with color Doppler imaging. Two limitations were identified: (1) lower resolution than mechanical volumetric transducers, and (2) narrow volume display. CONCLUSIONS Real-time direct 4D imaging with 360 degrees rotation for examination of fetal anatomic structures is feasible. This technology allows examination of fetal structures from multiple perspectives, in real time, without the need to move the transducer in the maternal abdomen. Further technological developments may overcome the limitations identified in this study.

Cervical varix as a cause of vaginal bleeding during pregnancy: prenatal diagnosis by color Doppler ultrasonography.

Abstract: Vaginal bleeding during pregnancy is a risk factor for adverse pregnancy outcome. Beyond 20 weeks of gestation, the most frequent causes of bleeding associated with maternal and perinatal morbidity and mortality are placenta previa and placental abruption. Cervical varix during pregnancy is a rare condition. To our knowledge, only six cases have been reported in the literature. Most of these cases were associated with preterm birth and high maternal morbidity. The optimal management and mode of delivery remain undetermined. We report a case of cervical varix diagnosed by transvaginal ultrasound at 21 weeks of gestation. The pregnancy was complicated by several episodes of vaginal bleeding and the patient delivered at 32 weeks. Color and power Doppler examination of the cervix played a key role in establishing the diagnosis.

OC100: The combined use of uterine artery Doppler and maternal plasma placental growth factor concentrations identifies patients at risk for early onset and/or severe pre-eclampsia

Abstract: Objective: Our objective was to describe variations of ovarian vascularization that occur in the estrus cycle of the ewe using an intravenous contrast agent. Method: Five ewes were investigated using power Doppler and contrast enhanced ultrasound after Sonovue injection at Day 0, 3, 5, 10 and 13 of the cycle in two successive estrus cycles. Transvaginal ultrasound monitoring of each ewe ovary was performed before and after a 4.8 ml dose of Sonovue. Usual Doppler parameters including resistance index and vessels quantification were collected. Following Sonovue injections enhancement parameters derived from the time intensity curves were mesured. Results: RI and vessels quantification, maximal enhancement intensity and wash-in period parameters changed significantly between ovaries and between the follicular and luteal period of the cycle. Uptake time, wash-out time, total time of enhancement, and area under the curve (AUC) were the parameters with no variation between ovaries. Wash-out time and AUC are also the two contrast parameters that do not change with cyclic changes. Conclusion: First, ewe is a good model to work on ovarian microvascularisation with contrast ultrasound. Second, if some of the parameters were modified during the hormonal cycle, others and specifically wash-out time do not vary and could be used for ovarian cancer detection.

OC34: Lung volume measurements by 3D ultrasound are not superior to biometry by 2D ultrasound to predict pulmonary hypoplasia in fetuses with musculoskeletal disorders

Abstract: Objective: To examine the relation between the fetal lung area to head circumference ratio (LHR) and lung volume by 3D ultrasound in normal fetuses and in fetuses with unilateral congenital diaphragmatic hernia (CDH). Methods: In 64 fetuses with CDH at 20–32 (median 26) weeks of gestation the contralateral lung volume and LHR were measured and the values were compared to those of 650 normal fetuses at 12–32 weeks. In the normal fetuses both lungs were assessed but in the 64 fetuses with CDH only the contralateral lung was measured because the ipsilateral lung could be visualized adequately in only 40 (62.5%) of the cases. Regression analysis was used to assess the significance of the association between lung volume and LHR. In the fetuses with CDH, the observed to expected LHR ratio was calculated. The expected LHR was the normal median for a given lung volume. The significance of differences between the observed to expected LHR in fetuses with CDH and normal fetuses was determined. Results: In normal fetuses the median LHR in both the left and right lungs increased with lung volume (Left LHR = 0.603 + 0.135 × left lung volume in mL −0.003 × left lung volume in mL2, r = 0.885, SD = 0.257, p < 0.001; Right LHR = 0.832 + 0.159 × right lung volume in mL −0.003 × right lung volume in mL2, r = 0.832, SD = 0.375, p < 0.001). In the fetuses with both left and right sided CDH the observed to expected LHR for lung volume was significantly lower than the respective value in normal fetuses. Conclusions: In normal fetuses the LHR increases with lung volume. In fetuses with CDH the LHR underestimates the actual lung volume as measured by 3D ultrasound.